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Sample records for mitochondrial neurogastrointestinal encephalopathy

  1. [Mitochondrial neurogastrointestinal encephalopathy disease].

    PubMed

    Benureau, A; Meyer, P; Maillet, O; Leboucq, N; Legras, S; Jeziorski, E; Fournier-Favre, S; Jeandel, C; Gaignard, P; Slama, A; Rivier, F; Roubertie, A; Carneiro, M

    2014-12-01

    Mitochondrial neurogastrointestinal encephalopathy disease (MNGIE) is a rare autosomal-recessive syndrome, resulting from mutations in the TYMP gene, located at 22q13. The mutation induces a thymidine phosphorylase (TP) deficit, which leads to a nucleotide pool imbalance and to instability of the mitochondrial DNA. The clinical picture regroups gastrointestinal dysmotility, cachexia, ptosis, ophthalmoplegia, peripheral neuropathy, and asymptomatic leukoencephalopathy. The prognosis is unfavorable. We present the case of a 14-year-old Caucasian female whose symptoms started in early childhood. The diagnosis was suspected after magnetic resonance imaging (MRI), performed given the atypical features of mental anorexia, which revealed white matter abnormalities. She presented chronic vomiting, postprandial abdominal pain, and problems gaining weight accompanied by cachexia. This diagnosis led to establishing proper care, in particular an enteral and parenteral nutrition program. There is no known specific effective treatment, but numerous studies are in progress. In this article, after reviewing the existing studies, we discuss the main diagnostic and therapeutic aspects of the disease. We argue for the necessity of performing a cerebral MRI given the atypical features of a patient with suspected mental anorexia (or when the clinical pattern of a patient with mental anorexia seems atypical), so that MNGIE can be ruled out. PMID:25282463

  2. Genetics Home Reference: mitochondrial neurogastrointestinal encephalopathy disease

    MedlinePlus

    ... modification) is used as a building block of DNA . Thymidine phosphorylase breaks down thymidine into smaller molecules, ... molecule is damaging to a particular kind of DNA known as mitochondrial DNA or mtDNA. Mitochondria are ...

  3. Diagnosis of mitochondrial neurogastrointestinal encephalopathy disease in gastrointestinal biopsies.

    PubMed

    Perez-Atayde, Antonio R

    2013-07-01

    A 14-year-old boy with mitochondrial neurogastrointestinal encephalopathy (MNGIE) disease had a lifelong history of failure to thrive and gastrointestinal symptoms including vomiting, pain, and diarrhea, leading to progressive cachexia. At the age of 9 years, after an extensive workup, the diagnosis of Crohn disease was strongly suspected, and he underwent colonoscopy with multiple biopsies. At 11 years of age, vision change and poor balance lead to a diagnosis of leukodystrophy by magnetic resonance imaging. Investigations for metachromatic leukodystrophy, adrenal leukodystrophy, and globoid cell leukodystrophy were all negative. A diagnosis of MNGIE disease was suspected when he continued deteriorating with gastrointestinal symptoms, multiple neurologic deficits, and encephalopathy. Markedly diminished thymidine phosphorylase activity and increased thymidine plasma levels confirmed the diagnosis of MNGIE. At autopsy, megamitochondria were observed by light microscopy in submucosal and myenteric ganglion cells and in smooth muscle cells of muscularis mucosae and muscularis propria, along the entire gastrointestinal tract from the esophagus to the rectum. Megamitochondria in ganglion cells were also observed in a retrospective review of the endoscopic intestinal biopsies taken at age 9 and 13 years and in the appendectomy specimen obtained 1 month before his demise. This study corroborates the presence of megamitochondria in gastrointestinal ganglion cells in MNGIE disease, better illustrates their detailed morphology, and describes for the first time similar structures in the cytoplasm of gastrointestinal smooth muscle cells. Pathologists should be able to recognize these structures by light microscopy and be aware of their association with primary mitochondriopathies. PMID:23453626

  4. Anesthetic Management of a Child with Mitochondrial Neurogastrointestinal Encephalopathy.

    PubMed

    Casarez, Vianey Q; Zavala, Acsa M; Owusu-Agyemang, Pascal; Hagan, Katherine

    2015-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder associated with deficiency of thymidine phosphorylase (TP). Associated manifestations include visual and hearing impairments, peripheral neuropathies, leukoencephalopathy, and malnutrition from concomitant gastrointestinal dysmotility and pseudoobstruction. Given the altered metabolic state in these patients, specific consideration of medication selection is advised. This case report will describe the anesthetic management used in a 10-year-old girl with MNGIE. She had multiple anesthetics while undergoing allogeneic hematopoietic stem cell transplantation. This case report will discuss the successful repeated use of the same anesthetic in this pediatric patient, with the avoidance of volatile anesthetic agents, propofol, and muscle relaxant. PMID:26124966

  5. Anesthetic Management of a Child with Mitochondrial Neurogastrointestinal Encephalopathy

    PubMed Central

    Casarez, Vianey Q.; Zavala, Acsa M.; Owusu-Agyemang, Pascal; Hagan, Katherine

    2015-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder associated with deficiency of thymidine phosphorylase (TP). Associated manifestations include visual and hearing impairments, peripheral neuropathies, leukoencephalopathy, and malnutrition from concomitant gastrointestinal dysmotility and pseudoobstruction. Given the altered metabolic state in these patients, specific consideration of medication selection is advised. This case report will describe the anesthetic management used in a 10-year-old girl with MNGIE. She had multiple anesthetics while undergoing allogeneic hematopoietic stem cell transplantation. This case report will discuss the successful repeated use of the same anesthetic in this pediatric patient, with the avoidance of volatile anesthetic agents, propofol, and muscle relaxant. PMID:26124966

  6. Nutrition Therapy for Mitochondrial Neurogastrointestinal Encephalopathy with Homozygous Mutation of the TYMP Gene.

    PubMed

    Wang, Jing; Chen, Wei; Wang, Fang; Wu, Dong; Qian, Jiaming; Kang, Junren; Li, Hailong; Ma, Enling

    2015-04-01

    Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is characterized by significant gastrointestinal dysmotility. Early and long-term nutritional therapy is highly recommended. We report a case of MNGIE in a patient who was undergoing long-term nutrition therapy. The patient was diagnosed with a serious symptom of fatty liver and hyperlipidemia complications, along with homozygous mutation of the thymidine phosphorylase (TYMP) gene (c.217G > A). To our knowledge, this is the first report of such a case. Herein, we describe preventive measures for the aforementioned complications and mitochondrial disease-specific nutritional therapy. PMID:25954734

  7. Nutrition Therapy for Mitochondrial Neurogastrointestinal Encephalopathy with Homozygous Mutation of the TYMP Gene

    PubMed Central

    Wang, Jing; Wang, Fang; Wu, Dong; Qian, Jiaming; Kang, Junren; Li, Hailong; Ma, Enling

    2015-01-01

    Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is characterized by significant gastrointestinal dysmotility. Early and long-term nutritional therapy is highly recommended. We report a case of MNGIE in a patient who was undergoing long-term nutrition therapy. The patient was diagnosed with a serious symptom of fatty liver and hyperlipidemia complications, along with homozygous mutation of the thymidine phosphorylase (TYMP) gene (c.217G > A). To our knowledge, this is the first report of such a case. Herein, we describe preventive measures for the aforementioned complications and mitochondrial disease-specific nutritional therapy. PMID:25954734

  8. Deoxynucleoside stress exacerbates the phenotype of a mouse model of mitochondrial neurogastrointestinal encephalopathy

    PubMed Central

    Garcia-Diaz, Beatriz; Garone, Caterina; Barca, Emanuele; Mojahed, Hamed; Gutierrez, Purification; Pizzorno, Giuseppe; Tanji, Kurenai; Arias-Mendoza, Fernando; Quinzii, Caterina M.

    2014-01-01

    Balanced pools of deoxyribonucleoside triphosphate precursors are required for DNA replication, and alterations of this balance are relevant to human mitochondrial diseases including mitochondrial neurogastrointestinal encephalopathy. In this disease, autosomal recessive TYMP mutations cause severe reductions of thymidine phosphorylase activity; marked elevations of the pyrimidine nucleosides thymidine and deoxyuridine in plasma and tissues, and somatic multiple deletions, depletion and site-specific point mutations of mitochondrial DNA. Thymidine phosphorylase and uridine phosphorylase double knockout mice recapitulated several features of these patients including thymidine phosphorylase activity deficiency, elevated thymidine and deoxyuridine in tissues, mitochondrial DNA depletion, respiratory chain defects and white matter changes. However, in contrast to patients with this disease, mutant mice showed mitochondrial alterations only in the brain. To test the hypothesis that elevated levels of nucleotides cause unbalanced deoxyribonucleoside triphosphate pools and, in turn, pathogenic mitochondrial DNA instability, we have stressed double knockout mice with exogenous thymidine and deoxyuridine, and assessed clinical, neuroradiological, histological, molecular, and biochemical consequences. Mutant mice treated with exogenous thymidine and deoxyuridine showed reduced survival, body weight, and muscle strength, relative to untreated animals. Moreover, in treated mutants, leukoencephalopathy, a hallmark of the disease, was enhanced and the small intestine showed a reduction of smooth muscle cells and increased fibrosis. Levels of mitochondrial DNA were depleted not only in the brain but also in the small intestine, and deoxyribonucleoside triphosphate imbalance was observed in the brain. The relative proportion, rather than the absolute amount of deoxyribonucleoside triphosphate, was critical for mitochondrial DNA maintenance. Thus, our results demonstrate that

  9. Deoxynucleoside stress exacerbates the phenotype of a mouse model of mitochondrial neurogastrointestinal encephalopathy.

    PubMed

    Garcia-Diaz, Beatriz; Garone, Caterina; Barca, Emanuele; Mojahed, Hamed; Gutierrez, Purification; Pizzorno, Giuseppe; Tanji, Kurenai; Arias-Mendoza, Fernando; Quinzii, Caterina M; Hirano, Michio

    2014-05-01

    Balanced pools of deoxyribonucleoside triphosphate precursors are required for DNA replication, and alterations of this balance are relevant to human mitochondrial diseases including mitochondrial neurogastrointestinal encephalopathy. In this disease, autosomal recessive TYMP mutations cause severe reductions of thymidine phosphorylase activity; marked elevations of the pyrimidine nucleosides thymidine and deoxyuridine in plasma and tissues, and somatic multiple deletions, depletion and site-specific point mutations of mitochondrial DNA. Thymidine phosphorylase and uridine phosphorylase double knockout mice recapitulated several features of these patients including thymidine phosphorylase activity deficiency, elevated thymidine and deoxyuridine in tissues, mitochondrial DNA depletion, respiratory chain defects and white matter changes. However, in contrast to patients with this disease, mutant mice showed mitochondrial alterations only in the brain. To test the hypothesis that elevated levels of nucleotides cause unbalanced deoxyribonucleoside triphosphate pools and, in turn, pathogenic mitochondrial DNA instability, we have stressed double knockout mice with exogenous thymidine and deoxyuridine, and assessed clinical, neuroradiological, histological, molecular, and biochemical consequences. Mutant mice treated with exogenous thymidine and deoxyuridine showed reduced survival, body weight, and muscle strength, relative to untreated animals. Moreover, in treated mutants, leukoencephalopathy, a hallmark of the disease, was enhanced and the small intestine showed a reduction of smooth muscle cells and increased fibrosis. Levels of mitochondrial DNA were depleted not only in the brain but also in the small intestine, and deoxyribonucleoside triphosphate imbalance was observed in the brain. The relative proportion, rather than the absolute amount of deoxyribonucleoside triphosphate, was critical for mitochondrial DNA maintenance. Thus, our results demonstrate that

  10. Non-myeloablative bone marrow transplant and platelet infusion can transiently improve the clinical outcome of mitochondrial neurogastrointestinal encephalopathy: a case report.

    PubMed

    Hussein, Eiman

    2013-10-01

    Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is caused by deficiency in thymidine phosphorylase (TP), that regulates thymidine (dThd) and deoxyuridine (dUrd). Toxic levels of dThd and dUrd can lead to mitochondrial dysfunction by impairing mitochondrial DNA replication, causing GI and neurologic deterioration. We studied the impact of bone marrow transplant (BMT) and platelets, as a source of TP on the clinical outcome of MNGIE. We report a case of MNGIE, who presented with severe vomiting. Over time, he was non-ambulatory and his GI symptoms got progressively worse with severe dysphagia, abdominal pain episodes, persistent vomiting and diarrhea. Being unfit for intense conditioning regimen, he received a mini BMT, with mild conditioning regimen. Bone marrow was obtained from his HLA fully matched brother. One month after transplantation, donor chimerism in peripheral blood was 33%. Excellent clinical responses were achieved 3 months after transplantation and circulating donor cell chimerism decreased to 24% with a significant increase in platelet TP activity. Ten months post transplant the patient's symptoms recurred and fresh single donor platelets were infused, with a significant increase in platelet TP activity. Mini BMT and platelet transfusion can transiently increase circulating TP activity and might prevent progress of this fatal disease. PMID:23410918

  11. Pitfalls in diagnosing mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Filosto, Massimiliano; Scarpelli, Mauro; Tonin, Paola; Testi, Silvia; Cotelli, Maria Sofia; Rossi, Mara; Salvi, Andrea; Grottolo, Alberto; Vielmi, Valentina; Todeschini, Alice; Fabrizi, Gian Maria; Padovani, Alessandro; Tomelleri, Giuliano

    2011-12-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder caused by mutations in the gene encoding thymidine phosphorylase and is characterized by external ophthalmoparesis, gastrointestinal dysmotility, leukoencephalopathy, and neuropathy. The availability of new therapeutic options (peritoneal dialysis, allogeneic stem cell transplantation, enzyme replacement) makes it necessary to diagnose the disease early, which is not always achieved due to the difficulty in recognizing this disorder, especially in case of atypical presentation. We describe three MNGIE patients with atypical onset of the disease. In the first patient the main symptoms were long-standing chronic fever, recurrent acute migrant arthritis, and gastrointestinal disorders mimicking autoimmune or inflammatory intestinal diseases; the second patient complained only of exercise intolerance and muscle cramps, and the third patient had a CIDP-like polyneuropathy. This study stresses the insidious heterogeneous clinical onset of some cases of MNGIE, expands the spectrum of the phenotype, and suggests considering MNGIE in the differential diagnosis of enteropathic arthritis, isolated exercise intolerance, and inflammatory polyneuropathies not responsive to the usual treatment. A better understanding of the clinical heterogeneity of MNGIE is necessary in order to diagnose atypical cases and promote early diagnosis, which is now absolutely necessary in view of the new available therapies. PMID:21503690

  12. Allogeneic haematopoietic stem cell transplantation for mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Halter, Joerg P; Michael, W; Schüpbach, M; Mandel, Hanna; Casali, Carlo; Orchard, Kim; Collin, Matthew; Valcarcel, David; Rovelli, Attilio; Filosto, Massimiliano; Dotti, Maria T; Marotta, Giuseppe; Pintos, Guillem; Barba, Pere; Accarino, Anna; Ferra, Christelle; Illa, Isabel; Beguin, Yves; Bakker, Jaap A; Boelens, Jaap J; de Coo, Irenaeus F M; Fay, Keith; Sue, Carolyn M; Nachbaur, David; Zoller, Heinz; Sobreira, Claudia; Pinto Simoes, Belinda; Hammans, Simon R; Savage, David; Martí, Ramon; Chinnery, Patrick F; Elhasid, Ronit; Gratwohl, Alois; Hirano, Michio

    2015-10-01

    Haematopoietic stem cell transplantation has been proposed as treatment for mitochondrial neurogastrointestinal encephalomyopathy, a rare fatal autosomal recessive disease due to TYMP mutations that result in thymidine phosphorylase deficiency. We conducted a retrospective analysis of all known patients suffering from mitochondrial neurogastrointestinal encephalomyopathy who underwent allogeneic haematopoietic stem cell transplantation between 2005 and 2011. Twenty-four patients, 11 males and 13 females, median age 25 years (range 10-41 years) treated with haematopoietic stem cell transplantation from related (n = 9) or unrelated donors (n = 15) in 15 institutions worldwide were analysed for outcome and its associated factors. Overall, 9 of 24 patients (37.5%) were alive at last follow-up with a median follow-up of these surviving patients of 1430 days. Deaths were attributed to transplant in nine (including two after a second transplant due to graft failure), and to mitochondrial neurogastrointestinal encephalomyopathy in six patients. Thymidine phosphorylase activity rose from undetectable to normal levels (median 697 nmol/h/mg protein, range 262-1285) in all survivors. Seven patients (29%) who were engrafted and living more than 2 years after transplantation, showed improvement of body mass index, gastrointestinal manifestations, and peripheral neuropathy. Univariate statistical analysis demonstrated that survival was associated with two defined pre-transplant characteristics: human leukocyte antigen match (10/10 versus <10/10) and disease characteristics (liver disease, history of gastrointestinal pseudo-obstruction or both). Allogeneic haematopoietic stem cell transplantation can restore thymidine phosphorylase enzyme function in patients with mitochondrial neurogastrointestinal encephalomyopathy and improve clinical manifestations of mitochondrial neurogastrointestinal encephalomyopathy in the long term. Allogeneic haematopoietic stem cell transplantation

  13. Abdominal pain related to mitochondrial neurogastrointestinal encephalomyopathy syndrome may benefit from splanchnic nerve blockade.

    PubMed

    Celebi, Nalan; Sahin, Altan; Canbay, Ozgür; Uzümcügil, Filiz; Aypar, Ulkü

    2006-10-01

    Patients diagnosed with abdominal pain related to mitochondrial neurogastrointestinal encephalopathy (MNGIE) may benefit from splanchnic nerve blockade. MNGIE, varying in age of onset and rate of progression, is caused by loss of function mutation in thymidine phosphorylase gene. Gastrointestinal dysmotility, pseudo-obstruction and demyelinating sensorimotor peripheral neuropathy (stocking-glove sensory loss, absent tendon reflexes, distal limb weakness, and wasting) are the most prominent manifestations. Patients usually die in early adulthood (mean 37.6 years; range 26-58 years). We report a case of an 18-year-old patient with MNGIE. Our patient's abdominal pain was relieved after splanchnic nerve blockade. PMID:16972839

  14. Clinical and genetic spectrum of mitochondrial neurogastrointestinal encephalomyopathy

    PubMed Central

    Garone, Caterina; Tadesse, Saba

    2011-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy is a rare multisystemic autosomic recessive disorder characterized by: onset typically before the age of 30 years; ptosis; progressive external ophthalmoplegia; gastrointestinal dysmotility; cachexia; peripheral neuropathy; and leucoencephalopathy. The disease is caused by mutations in the TYMP gene encoding thymidine phosphorylasethymine phosphorylase. Anecdotal reports suggest that allogeneic haematopoetic stem cell transplantation may be beneficial for mitochondrial neurogastrointestinal encephalomyopathy, but is associated with a high mortality. After selecting patients who fulfilled the clinical criteria for mitochondrial neurogastrointestinal encephalomyopathy and had severe thymidine phosphorylase deficiency in the buffy coat (<10% of normal activity), we reviewed their medical records and laboratory studies. We identified 102 patients (50 females) with mitochondrial neurogastrointestinal encephalomyopathy and an average age of 32.4 years (range 11–59 years). We found 20 novel TYMP mutations. The average age-at-onset was 17.9 years (range 5 months to 35 years); however, the majority of patients reported the first symptoms before the age of 12 years. The patient distribution suggests a relatively high prevalence in Europeans, while the mutation distribution suggests founder effects for a few mutations, such as c.866A>G in Europe and c.518T>G in the Dominican Republic, that could guide genetic screening in each location. Although the sequence of clinical manifestations in the disease varied, half of the patients initially had gastrointestinal symptoms. We confirmed anecdotal reports of intra- and inter-familial clinical variability and absence of genotype–phenotype correlation in the disease, suggesting genetic modifiers, environmental factors or both contribute to disease manifestations. Acute medical events such as infections often provoked worsening of symptoms, suggesting that careful monitoring and

  15. Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): biochemical features and therapeutic approaches.

    PubMed

    Lara, M C; Valentino, M L; Torres-Torronteras, J; Hirano, M; Martí, R

    2007-06-01

    Over the last 15 years, important research has expanded our knowledge of the clinical, molecular genetic, and biochemical features of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). The characterization of mitochondrial involvement in this disorder and the seminal determination of its genetic cause, have opened new possibilities for more detailed and deeper studies on the pathomechanisms in this progressive and fatal disease. It has been established that MNGIE is caused by mutations in the gene encoding thymidine phosphorylase (TP), which lead to absolute or nearly complete loss of its catalytic activity, producing systemic accumulations of its substrates, thymidine (dThd) and deoxyuridine (dUrd). Findings obtained from in vitro and in vivo studies indicate that the biochemical imbalances specifically impair mitochondrial DNA (mtDNA) replication, repair, or both leading to mitochondrial dysfunction. We have proposed that therapy for MNGIE should be aimed at reducing the concentrations of these toxic nucleosides to normal or nearly normal levels. The first treatment, allogeneic stem-cell transplantation (alloSCT) reported in 2006, produced a nearly full biochemical correction of the dThd and dUrd imbalances in blood. Clinical follow-up of this and other patients receiving alloSCT is necessary to determine whether this and other therapies based on a permanent restoration of TP will be effective treatment for MNGIE. PMID:17549623

  16. The Role of Brain MRI in Mitochondrial Neurogastrointestinal Encephalomyopathy

    PubMed Central

    Scarpelli, Mauro; Ricciardi, Giuseppe Kenneth; Beltramello, Alberto; Zocca, Isabella; Calabria, Francesca; Russignan, Anna; Zappini, Francesca; Cotelli, Maria Sofia; Padovani, Alessandro; Tomelleri, Giuliano; Filosto, Massimiliano; Tonin, Paola

    2013-01-01

    Summary Leukoencephalopathy is a hallmark of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) a devastating disorder characterized by ptosis, ophthalmoparesis, gastrointestinal dysfunction and polyneuropathy. To characterize MNGIE-associated leukoencephalopathy and to correlate it with clinical, biochemical and molecular data, four MNGIE patients with heterogeneous clinical phenotypes (enteropathic arthritis, exercise intolerance, CIDP-like phenotype and typical presentation) were studied by magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). Diffusion weighted imaging (DWI) with apparent diffusion coefficient (ADC) maps were also obtained. In two patients we also investigated the role of brain MRI in monitoring the evolution of leukoencephalopathy by performing follow-up imaging studies at an interval of one and two years. The extension and distribution of leukoencephalopathy were not clearly linked with age, phenotype or disease severity, and did not seem to be related to TYMP mutations, enzyme activity or pyrimidine levels. In the studied patients MRS revealed reduced N-acetyl-aspartate and increased choline signals. Although DWI appeared normal in all patients but one, ADC maps always showed moderate increased diffusivity. Leukoencephalopathy worsened over a two-year period in two patients, regardless of the clinical course, indicating a lack of correlation between clinical phenotype, size and progression of white matter abnormalities during this period. Brain MRI should be considered a very useful tool to diagnose both classical and atypical MNGIE. Serial MRIs in untreated and treated MNGIE patients will help to establish whether the leukoencephalopathy is a reversible condition or not. PMID:24199812

  17. Gastrointestinal dysmotility in mitochondrial neurogastrointestinal encephalomyopathy is caused by mitochondrial DNA depletion.

    PubMed

    Giordano, Carla; Sebastiani, Mariangela; De Giorgio, Roberto; Travaglini, Claudia; Tancredi, Andrea; Valentino, Maria Lucia; Bellan, Marzio; Cossarizza, Andrea; Hirano, Michio; d'Amati, Giulia; Carelli, Valerio

    2008-10-01

    Chronic intestinal pseudo-obstruction is a life-threatening condition of unknown pathogenic mechanisms. Chronic intestinal pseudo-obstruction can be a feature of mitochondrial disorders, such as mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), a rare autosomal-recessive syndrome, resulting from mutations in the thymidine phosphorylase gene. MNGIE patients show elevated circulating levels of thymidine and deoxyuridine, and accumulate somatic mitochondrial DNA (mtDNA) defects. The present study aimed to clarify the molecular basis of chronic intestinal pseudo-obstruction in MNGIE. Using laser capture microdissection, we correlated the histopathological features with mtDNA defects in different tissues from the gastrointestinal wall of five MNGIE and ten control patients. We found mtDNA depletion, mitochondrial proliferation, and smooth cell atrophy in the external layer of the muscularis propria, in the stomach and in the small intestine of MNGIE patients. In controls, the lowest amounts of mtDNA were present at the same sites, as compared with other layers of the gastrointestinal wall. We also observed mitochondrial proliferation and mtDNA depletion in small vessel endothelial and smooth muscle cells. Thus, visceral mitochondrial myopathy likely causes gastrointestinal dysmotility in MNGIE patients. The low baseline abundance of mtDNA molecules may predispose smooth muscle cells of the muscularis propria external layer to the toxic effects of thymidine and deoxyuridine, and exposure to high circulating levels of nucleosides may account for the mtDNA depletion observed in the small vessel wall. PMID:18787099

  18. Mitochondrial neurogastrointestinal encephalomyopathy: novel pathogenic mutations in thymidine phosphorylase gene in two Italian brothers.

    PubMed

    Libernini, Laura; Lupis, Chiara; Mastrangelo, Mario; Carrozzo, Rosalba; Santorelli, Filippo Maria; Inghilleri, Maurizio; Leuzzi, Vincenzo

    2012-08-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE, MIM 603041) is an autosomal recessive multisystem disorder occurring due to mutations in a nuclear gene coding for the enzyme thymidine phosphorylase (TYMP). Clinical features of MNGIE include gastrointestinal dysmotility, cachexia, ptosis or ophthalmoparesis, peripheral neuropathy, diffuse leukoencephalopathy, and signs of mitochondrial dysfunction in tissues. We report the clinical and molecular findings in two brothers in whom novel TYMP gene mutations (c.215-13_215delinsGCGTGA; c.1159 + 2T > A) were associated with different clinical presentations and outcomes. PMID:22618301

  19. A novel ECGF1 mutation in a Thai patient with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Kintarak, Jutatip; Liewluck, Teerin; Sangruchi, Tumtip; Hirano, Michio; Kulkantrakorn, Kongkiat; Muengtaweepongsa, Sombat

    2007-09-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive, multisystem disorder, which is clinically defined by ptosis, ophthalmoparesis, gastrointestinal dysmotility, cachexia, peripheral neuropathy, and leukoencephalopathy. MNGIE is caused by mutations in the nuclear gene, endothelial cell growth factor 1 (ECGF1), encoding thymidine phosphorylase (TP). ECGF1 mutations cause severe loss of TP activity, abnormal accumulations of thymidine and deoxyuridine in plasma, and alterations of mitochondrial DNA. Here, we report the first Thai patient with MNGIE confirmed genetically by the identification of a homozygous novel ECGF1 gene mutation, c.100insC, which causes a frameshift and premature truncation of TP protein. PMID:17544574

  20. A novel TYMP mutation in a French Canadian patient with mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Laforce, Robert; Valdmanis, Paul N; Dupré, Nicolas; Rouleau, Guy A; Turgeon, Alexis F; Savard, Martin

    2009-10-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder characterized by gastrointestinal, extraocular muscle, peripheral nerve, and cerebral white matter involvement. Mutations in the nuclear gene TYMP encoding for thymidine phosphorylase (TP) cause loss of TP activity, systemic accumulation of its substrates in plasma and tissues, as well as alterations in mitochondrial DNA including deletions, depletion, and somatic point mutations. To date, more than 30 mutations have been reported in diverse ethnic populations. We present herein the clinical, neuroimaging, neuromuscular, and molecular findings of the first French Canadian patient with MNGIE caused by a novel homozygous invariant splicing site (IVS5 +1 G>A) mutation of the TYMP gene. PMID:19523753

  1. Novel POLG mutations in progressive external ophthalmoplegia mimicking mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Van Goethem, Gert; Schwartz, Marianne; Löfgren, Ann; Dermaut, Bart; Van Broeckhoven, Christine; Vissing, John

    2003-07-01

    Autosomal recessive progressive external ophthalmoplegia (PEO) is one clinical disorder associated with multiple mitochondrial DNA deletions and can be caused by missense mutations in POLG, the gene encoding the mitochondrial DNA polymerase gamma. Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is another autosomal recessive disorder associated with PEO and multiple deletions of mitochondrial DNA in skeletal muscle. In several patients this disorder is caused by loss of function mutations in the gene encoding thymidine phosphorylase (TP). We report a recessive family with features of MNGIE but no leukoencephalopathy in which two patients carry three missense mutations in POLG, of which two are novel mutations (N846S and P587L). The third mutation was previously reported as a recessive POLG mutation (T251I). This finding indicates the need for POLG sequencing in patients with features of MNGIE without TP mutations. PMID:12825077

  2. Spontaneous abdominal esophageal perforation in a patient with mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Kalkan, I H; Köksal, A Ş; Evcimen, S; Sapmaz, F; Öztaş, E; Önder, F O; Güliter, S

    2015-02-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive multisystem disorder caused by thymidine phosphorylase deficiency. Severe denutrition is almost constant during the course of the disease which leads to severe malnutrition and requires long-term parenteral nutrition in most cases. Patients with MNGIE syndrome and chronic intestinal pseudo-obstruction have a particularly poor prognosis and they usually die around 40 years of age. Gastrointestinal perforation associated with MNGIE is extremely rare. Herein we present our unique case with MNGIE associated abdominal esophageal perforation. PMID:25649531

  3. Thymidine and deoxyuridine accumulate in tissues of patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Valentino, Maria Lucia; Martí, Ramon; Tadesse, Saba; López, Luis Carlos; Manes, Jose L; Lyzak, Judy; Hahn, Angelika; Carelli, Valerio; Hirano, Michio

    2007-07-24

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease due to ECGF1 gene mutations causing thymidine phosphorylase (TP) deficiency. Analysis of post-mortem samples of five MNGIE patients and two controls, revealed TP activity in all control tissues, but not in MNGIE samples. Converse to TP activity, thymidine and deoxyuridine were absent in control samples, but present in all tissues of MNGIE patients. Concentrations of both nucleosides in the tissues were generally higher than those observed in plasma of MNGIE patients. Our observations indicate that in the absence of TP activity, tissues accumulate nucleosides, which are excreted into plasma. PMID:17612528

  4. Characterization of a novel TYMP splice site mutation associated with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Taanman, Jan-Willem; Daras, Mariza; Albrecht, Juliane; Davie, Charles A; Mallam, Elizabeth A; Muddle, John R; Weatherall, Mark; Warner, Thomas T; Schapira, Anthony H V; Ginsberg, Lionel

    2009-02-01

    Mitochondrial neurogastrointestinal encephalomyopathy is an autosomal recessive disorder caused by loss-of-function mutations in the thymidine phosphorylase gene (TYMP). We report here a patient compound heterozygous for two TYMP mutations: a novel g.4009G>A transition affecting the consensus splice donor site of intron 9, and a previously reported g.675G>C splice site mutation. The novel mutation causes exon 9 skipping but leaves the reading frame intact; however, TYMP protein was not detected by immunoblot analysis, suggesting that neither mutant allele is expressed as protein. The patient's fibroblasts showed gradual loss of the mitochondrial DNA-encoded subunit I of cytochrome-c oxidase, suggesting a progressive mitochondrial DNA defect in culture. PMID:19056268

  5. Evaluation of gastrointestinal mtDNA depletion in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Giordano, Carla; d'Amati, Giulia

    2011-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare disease characterized by severe gastro-intestinal (GI) dysmotility caused by mutations in the thymidine phosphorylase gene. Thymidine phosphorylase (TP) is involved in the control of the pyrimidine nucleoside pool of the cell. Reduced TP activity induces nucleotide pool imbalances that in turn affect both the rate and fidelity of mtDNA replication, leading to multiple deletions and depletion of mtDNA. By using laser capture microdissection and quantitative real-time-polymerase chain reaction technique, we showed that depletion of mitochondrial DNA (mtDNA) is the most prominent molecular defect in the gut wall of MNGIE patients. Depletion affects severely the smooth muscle cells of muscularis propria and the skeletal muscle component of the upper esophagus, while ganglion cells of the myenteric plexus show only a milder mtDNA reduction. PMID:21761307

  6. Compound heterozygous mutations of TYMP as underlying causes of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Suh, Bum Chun; Jeong, Ha-Neul; Yoon, Byung Suk; Park, Ji Hoon; Kim, Hye Jin; Park, Sun Wha; Hwang, Jung Hee; Choi, Byung-Ok; Chung, Ki Wha

    2013-07-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), an autosomal recessive multiorgan disease, frequently associated with mutations in the thymidine phosphorylase (TYMP) gene. TYMP encodes thymidine phosphorylase (TP), which has an essential role in the nucleotide salvage pathway for mitochondrial DNA (mtDNA) replication. This study reports an MNGIE patient with novel compound heterozygous missense mutations (Thr151Pro and Leu270Pro) in TYMP. Each mutation was inherited from one parent. Neither mutation was found in the controls and the mutation sites were well conserved between different species. Neither large deletion nor causative point mutations were found in the mtDNA. The patient presented with MNGIE symptoms, including gastrointestinal discomfort, external ophthalmoplegia, pigmentary retinopathy and demyelinating type diffuse sensory motor polyneuropathy. The patient demonstrated an early-onset but mild phenotype, with 9.6% TP activity; therefore, patients with these compound heterozygous mutations may exhibit a mild phenotype with a variable onset age according to TP activity level. PMID:23685548

  7. Mitochondrial DNA depletion and thymidine phosphate pool dynamics in a cellular model of mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Pontarin, Giovanna; Ferraro, Paola; Valentino, Maria L; Hirano, Michio; Reichard, Peter; Bianchi, Vera

    2006-08-11

    Mitochondrial (mt) neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease associated with depletion, deletions, and point mutations of mtDNA. Patients lack a functional thymidine phosphorylase and their plasma contains high concentrations of thymidine and deoxyuridine; elevation of the corresponding triphosphates probably impairs normal mtDNA replication and repair. To study metabolic events leading to MNGIE we used as model systems skin and lung fibroblasts cultured in the presence of thymidine and/or deoxyuridine at concentrations close to those in the plasma of the patients, a more than 100-fold excess relative to controls. The two deoxynucleosides increased the mt and cytosolic dTTP pools of skin fibroblasts almost 2-fold in cycling cells and 8-fold in quiescent cells. During up to a two-month incubation of quiescent fibroblasts with thymidine (but not with deoxyuridine), mtDNA decreased to approximately 50% without showing deletions or point mutations. When we removed thymidine, but maintained the quiescent state, mtDNA recovered rapidly. With thymidine in the medium, the dTTP pool of quiescent cells turned over rapidly at a rate depending on the concentration of thymidine, due to increased degradation and resynthesis of dTMP in a substrate (=futile) cycle between thymidine kinase and 5'-deoxyribonucleotidase. The cycle limited the expansion of the dTTP pool at the expense of ATP hydrolysis. We propose that the substrate cycle represents a regulatory mechanism to protect cells from harmful increases of dTTP. Thus MNGIE patients may increase their consumption of ATP to counteract an unlimited expansion of the dTTP pool caused by circulating thymidine. PMID:16774911

  8. Limited dCTP availability accounts for mitochondrial DNA depletion in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    González-Vioque, Emiliano; Torres-Torronteras, Javier; Andreu, Antoni L; Martí, Ramon

    2011-03-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a severe human disease caused by mutations in TYMP, the gene encoding thymidine phosphorylase (TP). It belongs to a broader group of disorders characterized by a pronounced reduction in mitochondrial DNA (mtDNA) copy number in one or more tissues. In most cases, these disorders are caused by mutations in genes involved in deoxyribonucleoside triphosphate (dNTP) metabolism. It is generally accepted that imbalances in mitochondrial dNTP pools resulting from these mutations interfere with mtDNA replication. Nonetheless, the precise mechanistic details of this effect, in particular, how an excess of a given dNTP (e.g., imbalanced dTTP excess observed in TP deficiency) might lead to mtDNA depletion, remain largely unclear. Using an in organello replication experimental model with isolated murine liver mitochondria, we observed that overloads of dATP, dGTP, or dCTP did not reduce the mtDNA replication rate. In contrast, an excess of dTTP decreased mtDNA synthesis, but this effect was due to secondary dCTP depletion rather than to the dTTP excess in itself. This was confirmed in human cultured cells, demonstrating that our conclusions do not depend on the experimental model. Our results demonstrate that the mtDNA replication rate is unaffected by an excess of any of the 4 separate dNTPs and is limited by the availability of the dNTP present at the lowest concentration. Therefore, the availability of dNTP is the key factor that leads to mtDNA depletion rather than dNTP imbalances. These results provide the first test of the mechanism that accounts for mtDNA depletion in MNGIE and provide evidence that limited dNTP availability is the common cause of mtDNA depletion due to impaired anabolic or catabolic dNTP pathways. Thus, therapy approaches focusing on restoring the deficient substrates should be explored. PMID:21483760

  9. Cognitive dysfunction and hypogonadotrophic hypogonadism in a Brazilian patient with mitochondrial neurogastrointestinal encephalomyopathy and a novel ECGF1 mutation.

    PubMed

    Carod-Artal, F J; Herrero, M D; Lara, M C; López-Gallardo, E; Ruiz-Pesini, E; Martí, R; Montoya, J

    2007-05-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is caused by mutations in the thymidine phosphorylase gene (ECGF1). We present the first detailed report of a Brazilian MNGIE patient, harboring a novel ECGF1 homozygous mutation (C4202A, leading to a premature stop codon, S471X). Multiple deletions and the T5814C change were found in mitochondrial DNA. Together with gastrointestinal symptoms, endocrine involvement and memory dysfunction, not reported in MNGIE to date, were the most preeminent features. PMID:17437622

  10. ND5 is a hot-spot for multiple atypical mitochondrial DNA deletions in mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Nishigaki, Yutaka; Marti, Ramon; Hirano, Michio

    2004-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive multisystem disorder associated with depletion, multiple deletions and site-specific point mutations of mitochondrial DNA (mtDNA). MNGIE is caused by loss-of-function mutations in the gene encoding thymidine phosphorylase (TP; endothelial cell growth factor 1). Deficiency of TP leads to dramatically elevated levels of circulating thymidine and deoxyuridine. The alterations of pyrimidine nucleoside metabolism are hypothesized to cause imbalances of mitochondrial nucleotide pools that, in turn, may cause somatic alterations of mtDNA. We have now identified five major forms of mtDNA deletions in the skeletal muscle of MNGIE patients. While direct repeats and imperfectly homologous sequences appear to mediate the formation of mtDNA deletions, the nicotinamide adenine dinucleotide dehydrogenase 5 gene is a hot-spot for these rearrangements. A novel aspect of the mtDNA deletions in MNGIE is the presence of microdeletions at the imperfectly homologous breakpoints. PMID:14613972

  11. Endocarditis in Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE) Syndrome: The First in the Literature.

    PubMed

    Yolcu, Mustafa; Yolcu, Canan; Kaya, Zekeriya; Cakmak, Ender Ozgun; Sezen, Yusuf

    2014-10-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) syndromes is a rarely seen multisystem disorder with autosomal recessive inheritance due to thymidine phosphorylase gene mutation. It is characterized by progressive external ophthalmoplegia and/or pitosis, progressive gastrointestinal dismotility and abdominal pain, postprandial emesis, cachexia, demyelinating peripheral neuropathy, symmetrical and distal weakness especially in lower extremities and diffuse leucoencephalopathy in cranial magnetic resonance. Endocarditis is the infectious and inflammatory disease of the endothelial surface of the heart. MNGIE syndrome is a condition in which immune system is suppressed and infection risk increased. Herein we summarized a previously not reported endocarditis case in a patient with MNGIE syndrome who was under follow up for three years. In MNGIE syndrome of acute dyspnea, infective endocarditis should be kept in mind and prompt evaluation for surgical treatment should be done. PMID:25478431

  12. Mitochondrial neurogastrointestinal encephalomyopathy treated with peritoneal dialysis and bone marrow transplantation.

    PubMed

    Ariaudo, Claudia; Daidola, Germana; Ferrero, Bruno; Guarena, Cesare; Burdese, Manuel; Segoloni, Giuseppe Paolo; Biancone, Luigi

    2015-02-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare disease caused by thymidine phosphorylase deficiency which leads to toxic accumulations of thymidine (dThd) and deoxyuridine (dUrd). It lacks an established treatment and the prognosis is traditionally poor. We report a case of a young female patient with normal renal function and MNGIE treated by peritoneal dialysis (PD) and allogeneic bone marrow transplantation (BMT). PD was effective in reducing dThd and dUrd plasma levels and in improving clinical symptoms. To our knowledge, this is the first report on the beneficial effects of PD regarding MNGIE neurological symptoms. PD, therefore, should be considered especially in medically compromised patients as a supportive treatment to improve clinical conditions before BMT. PMID:24599829

  13. Endocarditis in Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE) Syndrome: The First in the Literature

    PubMed Central

    Yolcu, Canan; Kaya, Zekeriya; Cakmak, Ender Ozgun; Sezen, Yusuf

    2014-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) syndromes is a rarely seen multisystem disorder with autosomal recessive inheritance due to thymidine phosphorylase gene mutation. It is characterized by progressive external ophthalmoplegia and/or pitosis, progressive gastrointestinal dismotility and abdominal pain, postprandial emesis, cachexia, demyelinating peripheral neuropathy, symmetrical and distal weakness especially in lower extremities and diffuse leucoencephalopathy in cranial magnetic resonance. Endocarditis is the infectious and inflammatory disease of the endothelial surface of the heart. MNGIE syndrome is a condition in which immune system is suppressed and infection risk increased. Herein we summarized a previously not reported endocarditis case in a patient with MNGIE syndrome who was under follow up for three years. In MNGIE syndrome of acute dyspnea, infective endocarditis should be kept in mind and prompt evaluation for surgical treatment should be done. PMID:25478431

  14. Thymidine phosphorylase gene mutations in patients with mitochondrial neurogastrointestinal encephalomyopathy syndrome.

    PubMed

    Slama, A; Lacroix, C; Plante-Bordeneuve, V; Lombès, A; Conti, M; Reimund, J M; Auxenfants, E; Crenn, P; Laforêt, P; Joannard, A; Seguy, D; Pillant, H; Joly, P; Haut, S; Messing, B; Said, G; Legrand, A; Guiochon-Mantel, A

    2005-04-01

    The mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) syndrome is characterized by the association of gastrointestinal and neurological symptoms. It is a rare autosomal recessive mitochondrial disorder with multiple mitochondrial DNA deletions and/or depletion. It is caused by thymidine phosphorylase (TP) gene mutations resulting in a complete abolition of TP activity. We tested 31 unrelated patients presenting either with a complete MNGIE syndrome (8 patients), a severe intestinal pseudo-obstruction (10 patients), and multiple deletions and/or depletion of mitochondrial DNA (13 patients). All the tested patients presenting with a complete MNGIE had increased thymidine levels in plasma and urine, and no TP activity. The group with pseudo-obstruction syndrome had normal or partial reduction of TP activity. We found pathogenic mutations on TP gene only in the MNGIE syndrome group: all the MNGIE patients were compound heterozygous or homozygous for mutations in the TP gene. Eight of these mutations are yet unreported, confirming the lack of genotype/phenotype correlation in this syndrome. Enzymatic activity and thymidine level are thus rapid diagnosis tests to detect MNGIE affected patients prior to genetic testing for patients with gastrointestinal symptoms. PMID:15781193

  15. Mitochondrial Neurogastrointestinal Encephalomyopathy Treated with Stem Cell Transplantation: A Case Report and Review of Literature.

    PubMed

    Peedikayil, Musthafa Chalikandy; Kagevi, Eje Ingvar; Abufarhaneh, Ehab; Alsayed, Moeenaldeen Dia; Alzahrani, Hazzaa Abdulla

    2015-06-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder. The mutation in the ECGF1 gene causes severe deficiency of thymidine phosphorylase (TP), which in turn increases thymidine and deoxyuridine in the blood, serum, and tissue. The toxic levels of these products cause malfunction of the mitochondrial respiratory chain and mitochondrial DNA. Commonly, patients become symptomatic between 15 and 20 years of age (range 5 months to 35 years). The most commonly affected systems are gastrointestinal, followed by ocular, and nervous system. The disease is often fatal; high mortality rate is reported between 20 and 40 years of age. Treatment modalities that can increase thymidine phosphorylase activity and decrease thymidine and deoxy-uridine have shown symptomatic improvements in patients with MNGIE. Platelet transfusion, hemodialysis, peritoneal dialysis or allogeneic hematopoietic stem cell transplantation (HSCT) have been tried. The survival and long-term benefits of these measures are still not clear. Engrafted patients after stem cell transplantation have showed improvements in serum thymidine and deoxyuridine. We are reporting a case of MNGIE from Saudi Arabia, who underwent allogeneic hematopoietic stem cell transplantation. No MNGIE case has been previously reported from Saudi Arabia or the Gulf Arab countries. From the available literature, so far only 11 patients with MNGIE have undergone stem cell transplantation. PMID:25585305

  16. MicroRNA expression profile of a Malaysian Bajau family with familial mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Yong, F L; Wang, C W; Tan, K S

    2015-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare, autosomal recessive disorder associated with mutations in the thymidine phosphorylase (TYMP) gene. The main objective of this study was to characterize the genetic profiles of the deceased proband's family members (N = 4) using DNA sequencing and to determine miRNA deregulation in MNGIE using miRNA microarray profiling and bioinformatic analysis. We found that the genetic profile of the younger sister showed similar TYMP gene mutations as that of the proband with the exception of a heterozygous mutation in exon 10. The miRNA microarray revealed 55 significantly up-regulated and 65 significantly down-regulated miRNAs. These miRNAs have been implicated in various mitochondrial dynamics such as energy metabolism, Krebs cycle, mitochondria-associated apoptosis, and mitophagy. In conclusion, we demonstrate that blood miRNAs are deregulated in the pathogenesis of MNGIE and these changes may have therapeutic implications. Further experimental studies will be required to elucidate the functional miRNA-mRNA interactions in MNGIE. PMID:26535630

  17. Mitochondrial neurogastrointestinal encephalomyopathy in three siblings: clinical, genetic and neuroradiological features.

    PubMed

    Schüpbach, W M M; Vadday, K Madhavi; Schaller, A; Brekenfeld, C; Kappeler, L; Benoist, J F; Xuan-Huong, C Nguyen-Thi; Burgunder, J M; Seibold, F; Gallati, S; Mattle, H P

    2007-02-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder in which a nuclear mutation of the thymidine phosphorylase (TP) gene causes mitochondrial genomic dysfunction. Patients suffer from gastrointestinal dysmotility, cachexia, ptosis, external ophthalmoparesis, myopathy and polyneuropathy. Magnetic resonance imaging (MRI) shows leukoencephalopathy. We describe clinical, genetic and neuroradiological features of three brothers affected with MNGIE. Clinical examination, laboratory analyses, MRI and magnetic resonance spectroscopy (MRS) of the brain, and genetic analysis have been performed in all six members of the family with the three patients with MNGIE. Two of them are monozygous twins. They all suffered from gastrointestinal dysmotility, cachexia, ophthalmoplegia, muscular atrophies, and polyneuropathy. Urinary thymidine was elevated in the patients related to the severity of clinical disease, and urinary thymidine (normally not detectable) was also found in a heterozygous carrier. Brain MRI showed leukoencephalopathy in all patients; however, their cognitive functioning was normal. Brain MRS demonstrated reduced N-acetylaspartate and choline in severely affected areas. MRI of heterozygous carriers was normal. A new mutation (T92N) in the TP gene was identified. Urinary thymidine is for the first time reported to be detectable in a heterozygous carrier. MRS findings indicate loss of neurons, axons, and glial cells in patients with MNGIE, but not in heterozygous carriers. PMID:17294068

  18. Emergency surgery in chronic intestinal pseudo-obstruction due to mitochondrial neurogastrointestinal encephalomyopathy: case reports.

    PubMed

    Granero Castro, Pablo; Fernández Arias, Sebastián; Moreno Gijón, María; Alvarez Martínez, Paloma; Granero Trancón, José; Álvarez Pérez, Jose Antonio; Lamamie Clairac, Eduardo; González González, Juan José

    2010-01-01

    Chronic intestinal pseudo-obstruction (CIPO) is a syndrome characterized by recurrent clinical episodes of intestinal obstruction in the absence of any mechanical cause occluding the gut. There are multiple causes related to this rare syndrome. Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is one of the causes related to primary CIPO. MNGIE is caused by mutations in the gene encoding thymidine phosphorylase. These mutations lead to an accumulation of thymidine and deoxyuridine in blood and tissues of these patients. Toxic levels of these nucleosides induce mitochondrial DNA abnormalities leading to an abnormal intestinal motility.Herein, we described two rare cases of MNGIE syndrome associated with CIPO, which needed surgical treatment for gastrointestinal complications. In one patient, intra-abdominal hypertension and compartment syndrome generated as a result of the colonic distension forced to perform emergency surgery. In the other patient, a perforated duodenal diverticulum was the cause that forced to perform surgery. There is not a definitive treatment for MNGIE syndrome and survival does not exceed 40 years of age. Surgery only should be considered in some selected patients. PMID:21143863

  19. Liver as a source for thymidine phosphorylase replacement in mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Boschetti, Elisa; D'Alessandro, Roberto; Bianco, Francesca; Carelli, Valerio; Cenacchi, Giovanna; Pinna, Antonio D; Del Gaudio, Massimo; Rinaldi, Rita; Stanghellini, Vincenzo; Pironi, Loris; Rhoden, Kerry; Tugnoli, Vitaliano; Casali, Carlo; De Giorgio, Roberto

    2014-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive mitochondrial disease associated with mutations in the nuclear TYMP gene. As a result, the thymidine phosphorylase (TP) enzyme activity is markedly reduced leading to toxic accumulation of thymidine and therefore altered mitochondrial DNA. MNGIE is characterized by severe gastrointestinal dysmotility, neurological impairment, reduced life expectancy and poor quality of life. There are limited therapeutic options for MNGIE. In the attempt to restore TP activity, allogenic hematopoietic stem cell transplantation has been used as cellular source of TP. The results of this approach on ∼ 20 MNGIE patients showed gastrointestinal and neurological improvement, although the 5-year mortality rate is about 70%. In this study we tested whether the liver may serve as an alternative source of TP. We investigated 11 patients (7M; 35-55 years) who underwent hepatic resection for focal disorders. Margins of normal liver tissue were processed to identify, quantify and localize the TP protein by Western Blot, ELISA, and immunohistochemistry, and to evaluate TYMP mRNA expression by qPCR. Western Blot identified TP in liver with a TP/GAPDH ratio of 0.9 ± 0.5. ELISA estimated TP content as 0.5 ± 0.07 ng/μg of total protein. TP was identified in both nuclei and cytoplasm of hepatocytes and sinusoidal lining cells. Finally, TYMP mRNA was expressed in the liver. Overall, our study demonstrates that the liver is an important source of TP. Orthotopic liver transplantation may be considered as a therapeutic alternative for MNGIE patients. PMID:24802030

  20. Liver as a Source for Thymidine Phosphorylase Replacement in Mitochondrial Neurogastrointestinal Encephalomyopathy

    PubMed Central

    Boschetti, Elisa; D’Alessandro, Roberto; Bianco, Francesca; Carelli, Valerio; Cenacchi, Giovanna; Pinna, Antonio D.; Gaudio, Massimo Del; Rinaldi, Rita; Stanghellini, Vincenzo; Pironi, Loris; Rhoden, Kerry; Tugnoli, Vitaliano; Casali, Carlo; De Giorgio, Roberto

    2014-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive mitochondrial disease associated with mutations in the nuclear TYMP gene. As a result, the thymidine phosphorylase (TP) enzyme activity is markedly reduced leading to toxic accumulation of thymidine and therefore altered mitochondrial DNA. MNGIE is characterized by severe gastrointestinal dysmotility, neurological impairment, reduced life expectancy and poor quality of life. There are limited therapeutic options for MNGIE. In the attempt to restore TP activity, allogenic hematopoietic stem cell transplantation has been used as cellular source of TP. The results of this approach on ∼20 MNGIE patients showed gastrointestinal and neurological improvement, although the 5-year mortality rate is about 70%. In this study we tested whether the liver may serve as an alternative source of TP. We investigated 11 patients (7M; 35–55 years) who underwent hepatic resection for focal disorders. Margins of normal liver tissue were processed to identify, quantify and localize the TP protein by Western Blot, ELISA, and immunohistochemistry, and to evaluate TYMP mRNA expression by qPCR. Western Blot identified TP in liver with a TP/GAPDH ratio of 0.9±0.5. ELISA estimated TP content as 0.5±0.07 ng/μg of total protein. TP was identified in both nuclei and cytoplasm of hepatocytes and sinusoidal lining cells. Finally, TYMP mRNA was expressed in the liver. Overall, our study demonstrates that the liver is an important source of TP. Orthotopic liver transplantation may be considered as a therapeutic alternative for MNGIE patients. PMID:24802030

  1. ITA-MNGIE: an Italian regional and national survey for mitochondrial neuro-gastro-intestinal encephalomyopathy.

    PubMed

    D'Angelo, Roberto; Rinaldi, Rita; Carelli, Valerio; Boschetti, Elisa; Caporali, Leonardo; Capristo, Mariantonietta; Casali, Carlo; Cenacchi, Giovanna; Gramegna, Laura Ludovica; Lodi, Raffaele; Pinna, Antonio Daniele; Pironi, Loris; Stanzani, Marta; Tonon, Caterina; D'Alessandro, Roberto; De Giorgio, Roberto

    2016-07-01

    Mitochondrial neuro-gastro-intestinal encephalomyopathy (MNGIE) is a rare and unavoidably fatal disease due to mutations in thymidine phosphorylase (TP). Clinically it is characterized by gastrointestinal dysfunction, malnutrition/cachexia and neurological manifestations. MNGIE diagnosis remains a challenge mainly because of the complexity and rarity of the disease. Thus, our purposes were to promote a better knowledge of the disease in Emilia-Romagna region (ERR) by creating an accurate and dedicated network; to establish the minimal prevalence of MNGIE in Italy starting from ERR. Blood TP activity level was used as screening test to direct candidates to complete diagnostic work-up. During the study period of 1 year, only 10/71 units of ERR recruited 14 candidates. Their screening did not show TP activity changes. An Italian patient not resident in ERR was actually proved to have MNGIE. At the end of study in Italy there were nine cases of MNGIE; thus, the Italian prevalence of the disease is ~0.15/1,000,000 as a gross estimation. Our study confirms that MNGIE diagnosis is a difficult process which reflects the rarity of the disease and, as a result, a low level of awareness among specialists and physicians. Having available novel therapeutic options (e.g., allogenic hematopoietic stem cell transplantation and, more recently, liver transplantation) and an easy screening test, an early diagnosis should be sought before tissue damage occurs irreversibly. PMID:27007276

  2. Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) in two Mexican brothers harboring a novel mutation in the ECGF1 gene.

    PubMed

    Monroy, Nancy; Macías Kauffer, Luis R; Mutchinick, Osvaldo M

    2008-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disease caused by mutations in the thymidine phosphorylase gene located on chromosome 22q13.32-ter, causing defective functioning of the enzyme. At present 87 sporadic or familial cases have been reported and 52 different mutations identified. We present herein the clinical, neuromuscular and molecular findings of two affected brothers from an indigenous Mexican family living in a very small village not far from Mexico City, both brothers being homozygous for a novel mutation (Leu133Pro) in exon 3 of the ECGF1 gene. PMID:18280229

  3. Course and management of allogeneic stem cell transplantation in patients with mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Filosto, Massimiliano; Scarpelli, Mauro; Tonin, Paola; Lucchini, Giovanna; Pavan, Fabio; Santus, Francesca; Parini, Rossella; Donati, Maria Alice; Cotelli, Maria Sofia; Vielmi, Valentina; Todeschini, Alice; Canonico, Francesco; Tomelleri, Giuliano; Padovani, Alessandro; Rovelli, Attilio

    2012-12-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder caused by mutations in the gene encoding thymidine phosphorylase (TP). Allogeneic hematopoietic stem cell transplantation (HSCT) has been proposed as a treatment for patients with MNGIE and a standardized approach to HSCT in this condition has recently been developed. We report on the transplant course, management and short-term follow-up in two MNGIE patients who underwent HSCT. The source of stem cells was bone marrow taken from an HLA 9/10 allele-matched unrelated donor in the first patient and from an HLA 10/10 allele-matched sibling donor in the second. Both patients achieved full donor chimerism, and we observed restoration of buffy coat TP activity and lowered urine nucleoside concentrations in both of them. The post-transplant clinical follow-up showed improvement in gastrointestinal dysmotility, abdominal cramps and diarrhea. Neurological assessment remained unchanged. However, the first patient died 15 months after HSCT due to gastrointestinal obstruction and shock; the second patient died 8 months after the procedure due to respiratory distress following septic shock. Although HSCT corrects biochemical abnormalities and improves gastrointestinal symptoms, the procedure can be risky in subjects already in poor medical condition as are many MNGIE patients. Since transplant-related morbidity and mortality increases with progression of the disease and number of comorbidities, MNGIE patients should be submitted to HSCT when they are still relatively healthy, in order to minimize the complications of the procedure. Anyway, there is still incomplete knowledge on the natural history of the disease in many affected patients and it is not yet clear when the best time to do a transplant is. Further clues to the therapeutic potential of HSCT could result from a prolonged observation in a greater number of non-transplanted and transplanted patients, which would allow us

  4. Possible toxicity of tuberculostatic agents in a patient with a novel TYMP mutation leading to mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Mihaylova, Violeta; Guergueltcheva, Velina; Cherninkova, Sylvia; Penev, Luchezar; Georgieva, Galina; Stoyanova, Katya; Todorova, Albenaa; Tournev, Ivaylo

    2013-06-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive multisystemic disorder caused by TYMP gene mutations. Here, we report on the first MNGIE patient diagnosed in Bulgaria who carries a novel homozygous TYMP mutation (p.Leu347Pro). The patient presented with gastrointestinal complaints, cachexia, hearing loss, ptosis, ophthalmoparesis, polyneuropathy, cognitive impairment, and leukoencephalopathy on magnetic resonance imaging (MRI) examination of the brain. The patient's motor capacity declined significantly, leading to wheelchair dependence several months following administration of tuberculostatic treatment, suggesting mitochondrial toxicity of these agents. The advanced stage of the disease and the poor medical condition prevented us from performing allogenic hematopoietic stem cell transplantation (HSCT). Early diagnosis is important not only for genetic counseling but also in view of the timely treatment with allogenic HSCT. PMID:23590577

  5. Allogeneic hematopoietic SCT as treatment option for patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): a consensus conference proposal for a standardized approach

    PubMed Central

    Casali, C; Elhasid, R; Fay, K; Hammans, S; Illa, I; Kappeler, L; Krähenbühl, S; Lehmann, T; Mandel, H; Marti, R; Mattle, H; Orchard, K; Savage, D; Sue, CM; Valcarcel, D

    2015-01-01

    Allogeneic hematopoietic SCT (HSCT) has been proposed as a treatment for patients with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). HSCT has been performed in nine patients using different protocols with varying success. Based on this preliminary experience, participants of the first consensus conference propose a common approach to allogeneic HSCT in MNGIE. Standardization of the transplant protocol and the clinical and biochemical assessments will allow evaluation of the safety and efficacy of HSCT as well as optimization of therapy for patients with MNGIE. PMID:20436523

  6. Mitochondrial deoxynucleotide pools in quiescent fibroblasts: a possible model for mitochondrial neurogastrointestinal encephalomyopathy (MNGIE).

    PubMed

    Ferraro, Paola; Pontarin, Giovanna; Crocco, Laura; Fabris, Sonia; Reichard, Peter; Bianchi, Vera

    2005-07-01

    Mitochondrial (mt) DNA depletion syndromes can arise from genetic deficiencies for enzymes of dNTP metabolism, operating either inside or outside mitochondria. MNGIE is caused by the deficiency of cytosolic thymidine phosphorylase that degrades thymidine and deoxyuridine. The extracellular fluid of the patients contains 10-20 microM deoxynucleosides leading to changes in dTTP that may disturb mtDNA replication. In earlier work, we suggested that mt dTTP originates from two distinct pathways: (i) the reduction of ribonucleotides in the cytosol (in cycling cells) and (ii) intra-mt salvage of thymidine (in quiescent cells). In MNGIE and most other mtDNA depletion syndromes, quiescent cells are affected. Here, we demonstrate in quiescent fibroblasts (i) the existence of small mt dNTP pools, each usually 3-4% of the corresponding cytosolic pool; (ii) the rapid metabolic equilibrium between mt and cytosolic pools; and (iii) the intra-mt synthesis and rapid turnover of dTTP in the absence of DNA replication. Between 0.1 and 10 microM extracellular thymidine, intracellular thymidine rapidly approaches the extracellular concentration. We mimic the conditions of MNGIE by maintaining quiescent fibroblasts in 10-40 microM thymidine and/or deoxyuridine. Despite a large increase in intracellular thymidine concentration, cytosolic and mt dTTP increase at most 4-fold, maintaining their concentration for 41 days. Other dNTPs are marginally affected. Deoxyuridine does not increase the normal dNTP pools but gives rise to a small dUTP and a large dUMP pool, both turning over rapidly. We discuss these results in relation to MNGIE. PMID:15878850

  7. Poor Outcome in a Mitochondrial Neurogastrointestinal Encephalomyopathy Patient with a Novel TYMP Mutation: The Need for Early Diagnosis

    PubMed Central

    Scarpelli, Mauro; Russignan, Anna; Zombor, Melinda; Bereczki, Csaba; Zappini, Francesca; Buono, Romina; Bax, Bridget E.; Padovani, Alessandro; Tonin, Paola; Filosto, Massimiliano

    2012-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a devastating autosomal recessive disorder due to mutations in TYMP, which cause loss of function of thymidine phosphorylase (TP), nucleoside accumulation in plasma and tissues and mitochondrial dysfunction. The clinical picture includes progressive gastrointestinal dysmotility, cachexia, ptosis and ophthalmoparesis, peripheral neuropathy and diffuse leukoencephalopathy, which usually lead to death in early adulthood. Therapeutic options are currently available in clinical practice (allogeneic hematopoietic stem cell transplantation and carrier erythrocyte entrapped TP therapy) and newer, promising therapies are expected in the near future. However, successful treatment is strictly related to early diagnosis. We report on an incomplete MNGIE phenotype in a young man harboring the novel heterozygote c.199 C>T (Q67X) mutation in exon 2, and the previously reported c.866 A>C (E289A) mutation in exon 7 in TYMP. The correct diagnosis was achieved many years after the onset of symptoms and unfortunately, the patient died soon after diagnosis because of multiorgan failure due to severe malnutrition and cachexia before any therapeutic option could be tried. To date, early diagnosis is essential to ensure that patients have the opportunity to be treated. MNGIE should be suspected in all patients who present with both gastrointestinal and nervous system involvement, even if the classical complete phenotype is lacking. PMID:23341816

  8. Poor Outcome in a Mitochondrial Neurogastrointestinal Encephalomyopathy Patient with a Novel TYMP Mutation: The Need for Early Diagnosis.

    PubMed

    Scarpelli, Mauro; Russignan, Anna; Zombor, Melinda; Bereczki, Csaba; Zappini, Francesca; Buono, Romina; Bax, Bridget E; Padovani, Alessandro; Tonin, Paola; Filosto, Massimiliano

    2012-09-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a devastating autosomal recessive disorder due to mutations in TYMP, which cause loss of function of thymidine phosphorylase (TP), nucleoside accumulation in plasma and tissues and mitochondrial dysfunction. The clinical picture includes progressive gastrointestinal dysmotility, cachexia, ptosis and ophthalmoparesis, peripheral neuropathy and diffuse leukoencephalopathy, which usually lead to death in early adulthood. Therapeutic options are currently available in clinical practice (allogeneic hematopoietic stem cell transplantation and carrier erythrocyte entrapped TP therapy) and newer, promising therapies are expected in the near future. However, successful treatment is strictly related to early diagnosis. We report on an incomplete MNGIE phenotype in a young man harboring the novel heterozygote c.199 C>T (Q67X) mutation in exon 2, and the previously reported c.866 A>C (E289A) mutation in exon 7 in TYMP. The correct diagnosis was achieved many years after the onset of symptoms and unfortunately, the patient died soon after diagnosis because of multiorgan failure due to severe malnutrition and cachexia before any therapeutic option could be tried. To date, early diagnosis is essential to ensure that patients have the opportunity to be treated. MNGIE should be suspected in all patients who present with both gastrointestinal and nervous system involvement, even if the classical complete phenotype is lacking. PMID:23341816

  9. Progressive cerebral vascular degeneration with mitochondrial encephalopathy.

    PubMed

    Longo, Nicola; Schrijver, Iris; Vogel, Hannes; Pique, Lynn M; Cowan, Tina M; Pasquali, Marzia; Steinberg, Gary K; Hedlund, Gary L; Ernst, Sharon L; Gallagher, Renata C; Enns, Gregory M

    2008-02-01

    MELAS (mitochondrial encephalopathy with lactic acidosis and stroke-like episodes) is a maternally inherited disorder characterized by recurrent cerebral infarctions that do not conform to discreet vascular territories. Here we report on a patient who presented at 7 years of age with loss of consciousness and severe metabolic acidosis following vomiting and dehydration. She developed progressive sensorineural hearing loss, myopathy, ptosis, short stature, and mild developmental delays after normal early development. Biochemical testing identified metabolites characteristic of medium-chain acyl-CoA dehydrogenase (MCAD) deficiency (hexanoylglycine and suberylglycine), but also severe lactic acidemia (10-25 mM) and, in urine, excess of lactic acid, intermediates of the citric cycle, and marked ketonuria, suggesting mitochondrial dysfunction. She progressed rapidly to develop temporary cortical blindness. Brain imaging indicated generalized atrophy, more marked on the left side, in addition to white matter alterations consistent with a mitochondrial disorder. Magnetic resonance angiography indicated occlusion of the left cerebral artery with development of collateral circulation (Moyamoya syndrome). This process worsened over time to involve the other side of the brain. A muscle biopsy indicated the presence of numerous ragged red fibers. Molecular testing confirmed compound heterozygosity for the common mutation in the MCAD gene (985A>G) and a second pathogenic mutation (233T>C). MtDNA testing indicated that the muscle was almost homoplasmic for the 3243A>T mutation in tRNALeu, with a lower mutant load (about 50% heteroplasmy) in blood and skin fibroblasts. These results indicate that mitochondrial disorders may be associated with severe vascular disease resulting in Moyamoya syndrome. The contribution of the concomitant MCAD deficiency to the development of the phenotype in this case is unclear. PMID:18203188

  10. Thymidine phosphorylase is both a therapeutic and a suicide gene in a murine model of mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    López-Estévez, S; Ferrer, G; Torres-Torronteras, J; Mansilla, M J; Casacuberta-Serra, S; Martorell, L; Hirano, M; Martí, R; Barquinero, J

    2014-07-01

    Suicide gene therapy (SGT) is a promising strategy for treating cancer. In this work, we show that thymidine phosphorylase (TP) deficiency, the underlying genetic defect in mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), presents an opportunity to apply SGT using capecitabine, a commonly used prodrug that is converted into 5-fluorouracil by TP. Using an immortalised B-lymphoblastoid cell line from a patient with MNGIE, the tumourigenic EL-4 cell line, lentiviral vectors encoding TP and a double knockout (Tymp(-/-)Upp1(-/-)) murine model, we found that EL-4 cell-derived TP(+) tumours were exquisitely sensitive to capecitabine and generated a significant local bystander effect. In addition, we detected a spontaneous cytolytic immune response in a significant fraction of the animals surviving more than 20 days after termination of the therapy. These data indicate that, in individuals lacking TP expression, TP is a highly specific suicide gene, which can be used to treat tumours that could hypothetically arise in MNGIE patients undergoing gene therapy, as these tumours will likely originate from the gene-modified cells and will be selectively targeted by capecitabine. These observations have important implications for gene therapy for MNGIE. PMID:24807807

  11. Preclinical toxicity evaluation of erythrocyte-encapsulated thymidine phosphorylase in BALB/c mice and beagle dogs: an enzyme-replacement therapy for mitochondrial neurogastrointestinal encephalomyopathy.

    PubMed

    Levene, Michelle; Coleman, David G; Kilpatrick, Hugh C; Fairbanks, Lynette D; Gangadharan, Babunilayam; Gasson, Charlotte; Bax, Bridget E

    2013-01-01

    Erythrocyte-encapsulated thymidine phosphorylase (EE-TP) is currently under development as an enzyme replacement therapy for mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), an autosomal recessive disorder caused by a deficiency of thymidine phosphorylase. The rationale for the development of EE-TP is based on the pathologically elevated metabolites (thymidine and deoxyuridine) being able to freely diffuse across the erythrocyte membrane where the encapsulated enzyme catalyses their metabolism to the normal products. The systemic toxic potential of EE-TP was assessed when administered intermittently by iv bolus injection to BALB/c mice and Beagle dogs for 4 weeks. The studies consisted of one control group receiving sham-loaded erythrocytes twice weekly and two treated groups, one dosed once every 2 weeks and the other dosed twice per week. The administration of EE-TP to BALB/c mice resulted in thrombi/emboli in the lungs and spleen enlargement. These findings were also seen in the control group, and there was no relationship to the number of doses administered. In the dog, transient clinical signs were associated with EE-TP administration, suggestive of an immune-based reaction. Specific antithymidine phosphorylase antibodies were detected in two dogs and in a greater proportion of mice treated once every 2 weeks. Nonspecific antibodies were detected in all EE-TP-treated animals. In conclusion, these studies do not reveal serious toxicities that would preclude a clinical trial of EE-TP in patients with MNGIE, but caution should be taken for infusion-related reactions that may be related to the production of nonspecific antibodies or a cell-based immune response. PMID:22977166

  12. Deficiency of ECHS1 causes mitochondrial encephalopathy with cardiac involvement

    PubMed Central

    Haack, Tobias B; Jackson, Christopher B; Murayama, Kei; Kremer, Laura S; Schaller, André; Kotzaeridou, Urania; de Vries, Maaike C; Schottmann, Gudrun; Santra, Saikat; Büchner, Boriana; Wieland, Thomas; Graf, Elisabeth; Freisinger, Peter; Eggimann, Sandra; Ohtake, Akira; Okazaki, Yasushi; Kohda, Masakazu; Kishita, Yoshihito; Tokuzawa, Yoshimi; Sauer, Sascha; Memari, Yasin; Kolb-Kokocinski, Anja; Durbin, Richard; Hasselmann, Oswald; Cremer, Kirsten; Albrecht, Beate; Wieczorek, Dagmar; Engels, Hartmut; Hahn, Dagmar; Zink, Alexander M; Alston, Charlotte L; Taylor, Robert W; Rodenburg, Richard J; Trollmann, Regina; Sperl, Wolfgang; Strom, Tim M; Hoffmann, Georg F; Mayr, Johannes A; Meitinger, Thomas; Bolognini, Ramona; Schuelke, Markus; Nuoffer, Jean-Marc; Kölker, Stefan; Prokisch, Holger; Klopstock, Thomas

    2015-01-01

    Objective Short-chain enoyl-CoA hydratase (ECHS1) is a multifunctional mitochondrial matrix enzyme that is involved in the oxidation of fatty acids and essential amino acids such as valine. Here, we describe the broad phenotypic spectrum and pathobiochemistry of individuals with autosomal-recessive ECHS1 deficiency. Methods Using exome sequencing, we identified ten unrelated individuals carrying compound heterozygous or homozygous mutations in ECHS1. Functional investigations in patient-derived fibroblast cell lines included immunoblotting, enzyme activity measurement, and a palmitate loading assay. Results Patients showed a heterogeneous phenotype with disease onset in the first year of life and course ranging from neonatal death to survival into adulthood. The most prominent clinical features were encephalopathy (10/10), deafness (9/9), epilepsy (6/9), optic atrophy (6/10), and cardiomyopathy (4/10). Serum lactate was elevated and brain magnetic resonance imaging showed white matter changes or a Leigh-like pattern resembling disorders of mitochondrial energy metabolism. Analysis of patients’ fibroblast cell lines (6/10) provided further evidence for the pathogenicity of the respective mutations by showing reduced ECHS1 protein levels and reduced 2-enoyl-CoA hydratase activity. While serum acylcarnitine profiles were largely normal, in vitro palmitate loading of patient fibroblasts revealed increased butyrylcarnitine, unmasking the functional defect in mitochondrial β-oxidation of short-chain fatty acids. Urinary excretion of 2-methyl-2,3-dihydroxybutyrate – a potential derivative of acryloyl-CoA in the valine catabolic pathway – was significantly increased, indicating impaired valine oxidation. Interpretation In conclusion, we define the phenotypic spectrum of a new syndrome caused by ECHS1 deficiency. We speculate that both the β-oxidation defect and the block in l-valine metabolism, with accumulation of toxic methacrylyl-CoA and acryloyl

  13. Mutations in FBXL4 Cause Mitochondrial Encephalopathy and a Disorder of Mitochondrial DNA Maintenance

    PubMed Central

    Bonnen, Penelope E.; Yarham, John W.; Besse, Arnaud; Wu, Ping; Faqeih, Eissa A.; Al-Asmari, Ali Mohammad; Saleh, Mohammad A.M.; Eyaid, Wafaa; Hadeel, Alrukban; He, Langping; Smith, Frances; Yau, Shu; Simcox, Eve M.; Miwa, Satomi; Donti, Taraka; Abu-Amero, Khaled K.; Wong, Lee-Jun; Craigen, William J.; Graham, Brett H.; Scott, Kenneth L.; McFarland, Robert; Taylor, Robert W.

    2013-01-01

    Nuclear genetic disorders causing mitochondrial DNA (mtDNA) depletion are clinically and genetically heterogeneous, and the molecular etiology remains undiagnosed in the majority of cases. Through whole-exome sequencing, we identified recessive nonsense and splicing mutations in FBXL4 segregating in three unrelated consanguineous kindreds in which affected children present with a fatal encephalopathy, lactic acidosis, and severe mtDNA depletion in muscle. We show that FBXL4 is an F-box protein that colocalizes with mitochondria and that loss-of-function and splice mutations in this protein result in a severe respiratory chain deficiency, loss of mitochondrial membrane potential, and a disturbance of the dynamic mitochondrial network and nucleoid distribution in fibroblasts from affected individuals. Expression of the wild-type FBXL4 transcript in cell lines from two subjects fully rescued the levels of mtDNA copy number, leading to a correction of the mitochondrial biochemical deficit. Together our data demonstrate that mutations in FBXL4 are disease causing and establish FBXL4 as a mitochondrial protein with a possible role in maintaining mtDNA integrity and stability. PMID:23993193

  14. Infantile Encephalopathy and Defective Mitochondrial DNA Translation in Patients with Mutations of Mitochondrial Elongation Factors EFG1 and EFTu

    PubMed Central

    Valente, Lucia; Tiranti, Valeria; Marsano, René Massimiliano; Malfatti, Edoardo; Fernandez-Vizarra, Erika; Donnini, Claudia; Mereghetti, Paolo; De Gioia, Luca; Burlina, Alberto; Castellan, Claudio; Comi, Giacomo P.; Savasta, Salvatore; Ferrero, Iliana; Zeviani, Massimo

    2007-01-01

    Mitochondrial protein translation is a complex process performed within mitochondria by an apparatus composed of mitochondrial DNA (mtDNA)–encoded RNAs and nuclear DNA–encoded proteins. Although the latter by far outnumber the former, the vast majority of mitochondrial translation defects in humans have been associated with mutations in RNA-encoding mtDNA genes, whereas mutations in protein-encoding nuclear genes have been identified in a handful of cases. Genetic investigation involving patients with defective mitochondrial translation led us to the discovery of novel mutations in the mitochondrial elongation factor G1 (EFG1) in one affected baby and, for the first time, in the mitochondrial elongation factor Tu (EFTu) in another one. Both patients were affected by severe lactic acidosis and rapidly progressive, fatal encephalopathy. The EFG1-mutant patient had early-onset Leigh syndrome, whereas the EFTu-mutant patient had severe infantile macrocystic leukodystrophy with micropolygyria. Structural modeling enabled us to make predictions about the effects of the mutations at the molecular level. Yeast and mammalian cell systems proved the pathogenic role of the mutant alleles by functional complementation in vivo. Nuclear-gene abnormalities causing mitochondrial translation defects represent a new, potentially broad field of mitochondrial medicine. Investigation of these defects is important to expand the molecular characterization of mitochondrial disorders and also may contribute to the elucidation of the complex control mechanisms, which regulate this fundamental pathway of mtDNA homeostasis. PMID:17160893

  15. QIL1 mutation causes MICOS disassembly and early onset fatal mitochondrial encephalopathy with liver disease.

    PubMed

    Guarani, Virginia; Jardel, Claude; Chrétien, Dominique; Lombès, Anne; Bénit, Paule; Labasse, Clémence; Lacène, Emmanuelle; Bourillon, Agnès; Imbard, Apolline; Benoist, Jean-François; Dorboz, Imen; Gilleron, Mylène; Goetzman, Eric S; Gaignard, Pauline; Slama, Abdelhamid; Elmaleh-Bergès, Monique; Romero, Norma B; Rustin, Pierre; Ogier de Baulny, Hélène; Paulo, Joao A; Harper, J Wade; Schiff, Manuel

    2016-01-01

    Previously, we identified QIL1 as a subunit of mitochondrial contact site (MICOS) complex and demonstrated a role for QIL1 in MICOS assembly, mitochondrial respiration, and cristae formation critical for mitochondrial architecture (Guarani et al., 2015). Here, we identify QIL1 null alleles in two siblings displaying multiple clinical symptoms of early-onset fatal mitochondrial encephalopathy with liver disease, including defects in respiratory chain function in patient muscle. QIL1 absence in patients' fibroblasts was associated with MICOS disassembly, abnormal cristae, mild cytochrome c oxidase defect, and sensitivity to glucose withdrawal. QIL1 expression rescued cristae defects, and promoted re-accumulation of MICOS subunits to facilitate MICOS assembly. MICOS assembly and cristae morphology were not efficiently rescued by over-expression of other MICOS subunits in patient fibroblasts. Taken together, these data provide the first evidence of altered MICOS assembly linked with a human mitochondrial disease and confirm a central role for QIL1 in stable MICOS complex formation. PMID:27623147

  16. Mitochondria-Targeted Peptide Reverses Mitochondrial Dysfunction and Cognitive Deficits in Sepsis-Associated Encephalopathy.

    PubMed

    Wu, Jing; Zhang, Mingqiang; Hao, Shuangying; Jia, Ming; Ji, Muhuo; Qiu, Lili; Sun, Xiaoyan; Yang, Jianjun; Li, Kuanyu

    2015-08-01

    Sepsis-associated encephalopathy (SAE) is associated with increased mortality, morbidity, and long-term cognitive impairments. Its pathophysiology remains to be determined and an effective pharmacologic treatment is lacking. The goal of this study was to investigate the effects of the mitochondria-targeted peptide SS-31 on mitochondrial function and cognitive deficits in SAE mice. C57BL/6 male mice were randomly divided into sham, sham + SS-31, cecal ligation and puncture (CLP), and CLP + SS-31 groups. Peptide SS-31 (5 mg/kg) was intraperitoneally administrated immediately after operation and afterwards once daily for six consecutive days. Surviving mice were subjected to behavioral tests and the hippocampus was collected for biochemical analysis 7 days after operation. The results showed that CLP resulted in high mortality rate and cognitive deficits, representative characteristics of SAE. A physiological mechanistic investigation revealed that mitochondrial function of hippocampus was severely impaired, coupled with reactive oxygen species (ROS) generation, triggering neuronal apoptosis and inflammation. Notably, administration of peptide SS-31 protected the integrity of mitochondria, reversed the mitochondrial dysfunction, inhibited the apoptosis resulting from the release of cytochrome c, diminished the response of inflammation, and ultimately reversed the behavior deficits in the SAE mice. In conclusion, our data demonstrate that daily treatment with mitochondria-targeted peptide SS-31 reduces mortality rate and ameliorates cognitive deficits, which is possibly through a mechanism of reversing mitochondrial dysfunction and partial inhibition of neuronal apoptosis and inflammation in the hippocampus of the SAE mice. PMID:25288156

  17. Mitochondrial dysfunction as a mediator of hippocampal apoptosis in a model of hepatic encephalopathy.

    PubMed

    Bustamante, J; Lores-Arnaiz, S; Tallis, S; Roselló, D M; Lago, N; Lemberg, A; Boveris, A; Perazzo, J C

    2011-08-01

    In this study, we describe the presence of apoptosis, associated with a mitochondrial dysfunction in the hippocampus of animals in an experimental model defined as minimal hepatic encephalopathy (MHE). This experimental model was studied after 10 days of induced portal vein calibrated stricture, leading to portal hypertension and to a moderate hyperammonemia, without the presence of other evident central nervous system changes. The molecular mechanisms here proposed indicate the presence of apoptotic intrinsic pathways that point to hippocampal mitochondria as an important mediator of apoptosis in this experimental model. In this model of MHE, the presence of DNA fragmentation is documented by 2.3-times increased number of TUNEL-positive cells. These findings together with a higher ratio of the Bcl-2 family members Bax/Bcl-xL in the outer mitochondrial membrane of the MHE animals together with 11% of cytochrome c release indicate the presence of apoptosis in this experimental model. A detailed analysis of the hippocampal mitochondrial physiology was performed after mitochondrial isolation. The determination of the respiratory rate in the presence of malate plus glutamate and ADP showed a 45% decrease in respiratory control in MHE animals as compared with the sham group. A marked decrease of cytochrome oxidase (complex IV of the electron transport chain) was also observed, showing 46% less activity in hippocampal mitochondria from MHE animals. In addition, mitochondria from these animals showed less ability to maintain membrane potential (ΔΨ (m)) which was 13% lower than the sham group. Light scattering experiments showed that mitochondria from MHE animals were more sensitive to swell in the presence of increased calcium concentrations as compared with the sham group. In addition, in vitro studies performed in mitochondria from sham animals showed that mitochondrial permeability transition (MPT) could be a mitochondrial mediator of the apoptotic signaling in the

  18. [Higher Brain Dysfunction in Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS)].

    PubMed

    Ichikawa, Hiroo

    2016-02-01

    Stroke-like episodes are one of the cardinal features of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), and occur in 84-99% of the patients. The affected areas detected on neuroimaging do not have classical vascular distribution, and involve predominantly the temporal, parietal and occipital lobes. Thus, the neurological symptoms including higher brain dysfunction correlate with this topographical distribution. In association with the occipital lobe involvement, the most frequent symptom is cortical blindness. Other symptoms have been occasionally reported in case reports: visual agnosia, prosopagnosia, cortical deafness, auditory agnosia, topographical disorientation, various types of aphasia, hemispatial neglect, and so on. On the other hand, cognitive decline associated with more diffuse brain impairment rather than with focal stroke-like lesions has been postulated. This condition is also known as mitochondrial dementia. Domains of cognitive dysfunction include abstract reasoning, verbal memory, visual memory, language (naming and fluency), executive or constructive functions, attention, and visuospatial function. Cognitive functions and intellectual abilities may decline from initially minimal cognitive impairment to dementia. To date, the neuropsychological and neurologic impairment has been reported to be associated with cerebral lactic acidosis as estimated by ventricular spectroscopic lactate levels. PMID:26873235

  19. Impaired complex III assembly associated with BCS1L gene mutations in isolated mitochondrial encephalopathy.

    PubMed

    Fernandez-Vizarra, Erika; Bugiani, Marianna; Goffrini, Paola; Carrara, Franco; Farina, Laura; Procopio, Elena; Donati, Alice; Uziel, Graziella; Ferrero, Iliana; Zeviani, Massimo

    2007-05-15

    We investigated two unrelated children with an isolated defect of mitochondrial complex III activity. The clinical picture was characterized by a progressive encephalopathy featuring early-onset developmental delay, spasticity, seizures, lactic acidosis, brain atrophy and MRI signal changes in the basal ganglia. Both children were compound heterozygotes for novel mutations in the human bc1 synthesis like (BCS1L) gene, which encodes an AAA mitochondrial protein putatively involved in both iron homeostasis and complex III assembly. The pathogenic role of the mutations was confirmed by complementation assays, using a DeltaBcs1 strain of Saccharomyces cerevisiae. By investigating complex III assembly and the structural features of the BCS1L gene product in skeletal muscle, cultured fibroblasts and lymphoblastoid cell lines from our patients, we have demonstrated, for the first time in a mammalian system, that a major function of BCS1L is to promote the maturation of complex III and, more specifically, the incorporation of the Rieske iron-sulfur protein into the nascent complex. Defective BCS1L leads to the formation of a catalytically inactive, structurally unstable complex III. We have also shown that BCS1L is contained within a high-molecular-weight supramolecular complex which is clearly distinct from complex III intermediates. PMID:17403714

  20. Progress in Diagnosing Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like Episodes

    PubMed Central

    Wang, Ying-Xin; Le, Wei-Dong

    2015-01-01

    Objective: Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a progressive, multisystem affected mitochondrial disease associated with a number of disease-related defective genes. MELAS has unpredictable presentations and clinical course, and it can be commonly misdiagnosed as encephalitis, cerebral infarction, or brain neoplasms. This review aimed to update the diagnosis progress in MELAS, which may provide better understanding of the disease nature and help make the right diagnosis as well. Data Sources: The data used in this review came from published peer review articles from October 1984 to October 2014, which were obtained from PubMed. The search term is “MELAS”. Study Selection: Information selected from those reported studies is mainly based on the progress on clinical features, blood biochemistry, neuroimaging, muscle biopsy, and genetics in diagnosing MELAS. Results: MELAS has a wide heterogeneity in genetics and clinical manifestations. The relationship between mutations and phenotypes remains unclear. Advanced serial functional magnetic resonance imaging (MRI) can provide directional information on this disease. Muscle biopsy has meaningful value in diagnosing MELAS, which shows the presence of ragged red fibers and mosaic appearance of cytochrome oxidase negative fibers. Genetic studies have reported that approximately 80% of MELAS cases are caused by the mutation m.3243A>G of the mitochondrial transfer RNA (Leu (UUR)) gene (MT-TL1). Conclusions: MELAS involves multiple systems with variable clinical symptoms and recurrent episodes. The prognosis of MELAS patients depends on timely diagnosis. Therefore, overall diagnosis of MELAS should be based on the maternal inheritance family history, clinical manifestation, and findings from serial MRI, muscle biopsy, and genetics. PMID:26112726

  1. Unbalanced deoxynucleotide pools cause mitochondrial DNA instability in thymidine phosphorylase-deficient mice.

    PubMed

    López, Luis C; Akman, Hasan O; García-Cazorla, Angeles; Dorado, Beatriz; Martí, Ramón; Nishino, Ichizo; Tadesse, Saba; Pizzorno, Giuseppe; Shungu, Dikoma; Bonilla, Eduardo; Tanji, Kurenai; Hirano, Michio

    2009-02-15

    Replication and repair of DNA require equilibrated pools of deoxynucleoside triphosphate precursors. This concept has been proven by in vitro studies over many years, but in vivo models are required to demonstrate its relevance to multicellular organisms and to human diseases. Accordingly, we have generated thymidine phosphorylase (TP) and uridine phosphorylase (UP) double knockout (TP(-/-)UP(-/-)) mice, which show severe TP deficiency, increased thymidine and deoxyuridine in tissues and elevated mitochondrial deoxythymidine triphosphate. As consequences of the nucleotide pool imbalances, brains of mutant mice developed partial depletion of mtDNA, deficiencies of respiratory chain complexes and encephalopathy. These findings largely account for the pathogenesis of mitochondrial neurogastrointestinal encephalopathy (MNGIE), the first inherited human disorder of nucleoside metabolism associated with somatic DNA instability. PMID:19028666

  2. [Mitochondrial disease and mitochondrial DNA depletion syndromes].

    PubMed

    Huang, Chin-Chang; Hsu, Chang-Huang

    2009-12-01

    Mitochondria is an intracellular double membrane-bound structure and it can provide energy for intracellular metabolism. The metabolism includes Krebs cycle, beta-oxidation and lipid synthesis. The density of mitochondria is different in various tissues dependent upon the demands of oxidative phosphorylation. Mitochondrial diseases can occur by defects either in mitochondrial DNA or nuclear DNA. Human mitochondrial DNA (mtDNA) encoding for 22 tRNAs, 2 rRNAs and 13 mRNAs that are translated in the mitochondria. Mitochondrial genetic diseases are most resulted from defects in the mtDNA which may be point mutations, deletions, or mitochondrial DNA depletion. These patterns of inheritance in mitochondrial diseases include sporadic, maternally inherited, or of Mendelian inheritance. Mitochondrial DNA depletion is caused by defects in the nuclear genes that are responsible for maintenance of integrity of mtDNA or deoxyribonucelotide pools and mtDNA biogenesis. The mtDNA depletion syndrome (MDS) includes the following categories: progressive external ophthalmoplegia (PEO), predominant myopathy, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), sensory-ataxic neuropathy, dysarthria, and ophthalmoplegia (SANDO) and hepato-encephalopathy. The most common tissues or organs involved in MDS and related disorders include the brain, liver and muscles. These involved genes are divided into two groups including 1) DNA polymerase gamma (POLG, POLG2) and Twinkle genes whose products function directly at the mtDNA replication fork, and 2) adenine nucleotide translocator 1, thymidine phosphorylase, thymidine kinase 2, deoxyguanosine kinase, ADP-forming succinyl-CoA synthetase ligase, MPV17 whose products supply the mitochondria with deoxyribonucleotide triphosphate pools needed for mtDNA replication, and possible mutation in the RRM2B gene. The development has provided new information about the importance of the biosynthetic pathway of the nucleotides for mtDNA replication

  3. Sex-dependent mitochondrial respiratory impairment and oxidative stress in a rat model of neonatal hypoxic-ischemic encephalopathy.

    PubMed

    Demarest, Tyler G; Schuh, Rosemary A; Waddell, Jaylyn; McKenna, Mary C; Fiskum, Gary

    2016-06-01

    Increased male susceptibility to long-term cognitive deficits is well described in clinical and experimental studies of neonatal hypoxic-ischemic encephalopathy. While cell death signaling pathways are known to be sexually dimorphic, a sex-dependent pathophysiological mechanism preceding the majority of secondary cell death has yet to be described. Mitochondrial dysfunction contributes to cell death following cerebral hypoxic-ischemia (HI). Several lines of evidence suggest that there are sex differences in the mitochondrial metabolism of adult mammals. Therefore, this study tested the hypothesis that brain mitochondrial respiratory impairment and associated oxidative stress is more severe in males than females following HI. Maximal brain mitochondrial respiration during oxidative phosphorylation was two-fold more impaired in males following HI. The endogenous antioxidant glutathione was 30% higher in the brain of sham females compared to males. Females also exhibited increased glutathione peroxidase (GPx) activity following HI injury. Conversely, males displayed a reduction in mitochondrial GPx4 protein levels and mitochondrial GPx activity. Moreover, a 3-4-fold increase in oxidative protein carbonylation was observed in the cortex, perirhinal cortex, and hippocampus of injured males, but not females. These data provide the first evidence for sex-dependent mitochondrial respiratory dysfunction and oxidative damage, which may contribute to the relative male susceptibility to adverse long-term outcomes following HI. Lower basal GSH levels, lower post-hypoxic mitochondrial glutathione peroxidase (mtGPx) activity, and mitochondrial glutathione peroxidase 4 (mtGPx4) protein levels may contribute to the susceptibility of the male brain to oxidative damage and mitochondrial dysfunction following neonatal hypoxic-ischemia (HI). Treatment of male pups with acetyl-L-carnitine (ALCAR) protects against the loss of mtGPx activity, mtGPx4 protein, and increases in protein

  4. A novel de novo dominant negative mutation in DNM1L impairs mitochondrial fission and presents as childhood epileptic encephalopathy.

    PubMed

    Fahrner, Jill A; Liu, Raymond; Perry, Michael Scott; Klein, Jessica; Chan, David C

    2016-08-01

    DNM1L encodes dynamin-related protein 1 (DRP1/DLP1), a key component of the mitochondrial fission machinery that is essential for proper functioning of the mammalian brain. Previously reported probands with de novo missense mutations in DNM1L presented in the first year of life with severe encephalopathy and refractory epilepsy, with several dying within the first several weeks after birth. In contrast, we report identical novel missense mutations in DNM1L in two unrelated probands who experienced normal development for several years before presenting with refractory focal status epilepticus and subsequent rapid neurological decline. We expand the phenotype of DNM1L-related mitochondrial fission defects, reveal common unique clinical characteristics and imaging findings, and compare the cellular impact of this novel mutation to the previously reported A395D lethal variant. We demonstrate that our R403C mutation, which resides in the assembly region of DRP1, acts by a dominant-negative mechanism and reduces oligomerization, mitochondrial fission activity, and mitochondrial recruitment of DRP1, but to a lesser extent compared to the A395D mutation. In contrast to the initial report of neonatal lethality resulting from DNM1L mutation and DRP1 dysfunction, our results show that milder DRP1 impairment is compatible with normal early development and subsequently results in a distinct set of neurological findings. In addition, we identify a common pathogenic mechanism whereby DNM1L mutations impair mitochondrial fission. © 2016 Wiley Periodicals, Inc. PMID:27145208

  5. Lack of age-related clinical progression in PGC-1α-deficient mice - implications for mitochondrial encephalopathies.

    PubMed

    Szalardy, Levente; Molnar, Mate; Torok, Rita; Zadori, Denes; Kovacs, Gabor G; Vecsei, Laszlo; Klivenyi, Peter

    2016-10-15

    Impaired peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) function has been demonstrated in several neurodegenerative diseases, and murine whole-body knockouts of PGC-1α have been considered as models for Huntington's disease. Recent neuropathological studies, however, rather propose these animals to be morphological models of mitochondrial encephalopathies, with special reminiscence of Kearns-Sayre syndrome. PGC-1α-deficient animals have already been subjected to behavioral assessments; however, the contradictory findings and the paucity of data assessing long-term progression necessitated further examinations. This study provides a comprehensive neurological phenotypic profiling of full-length-(FL-)PGC-1α-deficient mice in a broad age spectrum, with special focus on previously controversial findings, the issue of long-term phenotypic progression, the histopathological assessment of previously non-characterized tissues of potential clinicopathological relevance, and the gene expression profile of novel brain-specific isoforms of PGC-1α. Our findings demonstrate moderate hypomotility with signs of gait and trunk ataxia in addition to severe impairments in coordination and muscle strength in FL-PGC-1α-deficient mice, phenotypic features consistent of a mitochondrial disease. Intriguingly, however, these early alterations did not progress with age, the understanding of which may unveil mechanisms of potential therapeutic relevance, as discussed. The observed phenotype did not associate with retinal or spinal cord alterations, and was accompanied by mild myopathic changes. Based on these, FL-PGC-1α-deficient mice can be regarded not only as morphological but behavioral models of mitochondrial encephalopathies, with an important temporal limitation that has now been clarified. The mechanisms capable of halting a potentially lethal phenotype are to be unveiled, as they may hold therapeutic value for mitochondrial diseases. PMID

  6. Mitochondrial diseases caused by toxic compound accumulation: from etiopathology to therapeutic approaches.

    PubMed

    Di Meo, Ivano; Lamperti, Costanza; Tiranti, Valeria

    2015-10-01

    Mitochondrial disorders are a group of highly invalidating human conditions for which effective treatment is currently unavailable and characterized by faulty energy supply due to defective oxidative phosphorylation (OXPHOS). Given the complexity of mitochondrial genetics and biochemistry, mitochondrial inherited diseases may present with a vast range of symptoms, organ involvement, severity, age of onset, and outcome. Despite the wide spectrum of clinical signs and biochemical underpinnings of this group of dis-orders, some common traits can be identified, based on both pathogenic mechanisms and potential therapeutic approaches. Here, we will review two peculiar mitochondrial disorders, ethylmalonic encephalopathy (EE) and mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), caused by mutations in the ETHE1 and TYMP nuclear genes, respectively. ETHE1 encodes for a mitochondrial enzyme involved in sulfide detoxification and TYMP for a cytosolic enzyme involved in the thymidine/deoxyuridine catabolic pathway. We will discuss these two clinical entities as a paradigm of mitochondrial diseases caused by the accumulation of compounds normally present in traces, which exerts a toxic and inhibitory effect on the OXPHOS system. PMID:26194912

  7. Mitochondrial diseases caused by toxic compound accumulation: from etiopathology to therapeutic approaches

    PubMed Central

    Di Meo, Ivano; Lamperti, Costanza; Tiranti, Valeria

    2015-01-01

    Mitochondrial disorders are a group of highly invalidating human conditions for which effective treatment is currently unavailable and characterized by faulty energy supply due to defective oxidative phosphorylation (OXPHOS). Given the complexity of mitochondrial genetics and biochemistry, mitochondrial inherited diseases may present with a vast range of symptoms, organ involvement, severity, age of onset, and outcome. Despite the wide spectrum of clinical signs and biochemical underpinnings of this group of dis-orders, some common traits can be identified, based on both pathogenic mechanisms and potential therapeutic approaches. Here, we will review two peculiar mitochondrial disorders, ethylmalonic encephalopathy (EE) and mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), caused by mutations in the ETHE1 and TYMP nuclear genes, respectively. ETHE1 encodes for a mitochondrial enzyme involved in sulfide detoxification and TYMP for a cytosolic enzyme involved in the thymidine/deoxyuridine catabolic pathway. We will discuss these two clinical entities as a paradigm of mitochondrial diseases caused by the accumulation of compounds normally present in traces, which exerts a toxic and inhibitory effect on the OXPHOS system. PMID:26194912

  8. Hepatic Encephalopathy

    MedlinePlus Videos and Cool Tools

    ... is Hepatic Encephalopathy? Hepatic Encephalopathy, sometimes referred to as portosystemic encephalopathy or PSE, is a condition that ... medical care is an important factor in staying as healthy as possible. The American Liver Foundation is ...

  9. BRAT1 mutations are associated with infantile epileptic encephalopathy, mitochondrial dysfunction, and survival into childhood.

    PubMed

    Horn, Denise; Weschke, Bernhard; Knierim, Ellen; Fischer-Zirnsak, Björn; Stenzel, Werner; Schuelke, Markus; Zemojtel, Tomasz

    2016-09-01

    We describe two siblings who were affected with early onset focal seizures, severe progressive postnatal microcephaly, muscular hypertonia, feeding problems and bouts of apnea, only minimal psychomotor development, as well as death in infancy and childhood. We identified compound heterozygous mutations in BRAT1 exons 5 (c.638_639insA) and 8 (c.1134+1G>A) in one affected child via next-generation sequencing of the disease-associated genome followed by phenotype-driven bioinformatic analysis. Sanger sequencing confirmed the presence of these mutations in both patients and a heterozygote status of the parents. Whereas the frameshift mutation (c.638_639insA) has been described in one family, the splice-site mutation (c.1134+1G>A) is novel. In contrast to all cases published so far, one of our patients showed a considerably milder clinical course with survival into childhood. Investigation of a skeletal muscle biopsy showed a severely reduced COX enzyme histochemical staining, indicating mitochondrial dysfunction. Our data expand the clinical and mutational spectrum of the BRAT1-associated phenotype. © 2016 Wiley Periodicals, Inc. PMID:27282648

  10. A Homozygous Mutation in LYRM7/MZM1L Associated with Early Onset Encephalopathy, Lactic Acidosis, and Severe Reduction of Mitochondrial Complex III Activity

    PubMed Central

    Invernizzi, Federica; Tigano, Marco; Dallabona, Cristina; Donnini, Claudia; Ferrero, Ileana; Cremonte, Maurizio; Ghezzi, Daniele; Lamperti, Costanza; Zeviani, Massimo

    2013-01-01

    Mutations in nuclear genes associated with defective complex III (cIII) of the mitochondrial respiratory chain are rare, having been found in only two cIII assembly factors and, as private changes in single families, three cIII structural subunits. Recently, human LYRM7/MZM1L, the ortholog of yeast MZM1, has been identified as a new assembly factor for cIII. In a baby patient with early onset, severe encephalopathy, lactic acidosis and profound, isolated cIII deficiency in skeletal muscle, we identified a disease-segregating homozygous mutation (c.73G>A) in LYRM7/MZM1L, predicting a drastic change in a highly conserved amino-acid residue (p.Asp25Asn). In a mzm1Δ yeast strain, the expression of a mzm1D25N mutant allele caused temperature-sensitive respiratory growth defect, decreased oxygen consumption, impaired maturation/stabilization of the Rieske Fe–S protein, and reduced complex III activity and amount. LYRM7/MZM1L is a novel disease gene, causing cIII-defective, early onset, severe mitochondrial encephalopathy. PMID:24014394

  11. Large copy number variations in combination with point mutations in the TYMP and SCO2 genes found in two patients with mitochondrial disorders

    PubMed Central

    Vondráčková, Alžběta; Veselá, Kateřina; Kratochvílová, Hana; Kučerová Vidrová, Vendula; Vinšová, Kamila; Stránecký, Viktor; Honzík, Tomáš; Hansíková, Hana; Zeman, Jiří; Tesařová, Markéta

    2014-01-01

    Mitochondrial disorders are caused by defects in mitochondrial or nuclear DNA. Although the existence of large deletions in mitochondrial DNA (mtDNA) is well known, deletions affecting whole genes are not commonly described in patients with mitochondrial disorders. Based on the results of whole-genome analyses, copy number variations (CNVs) occur frequently in the human genome and may overlap with many genes associated with clinical phenotypes. We report the discovery of two large heterozygous CNVs on 22q13.33 in two patients with mitochondrial disorders. The first patient harboured a novel point mutation c.667G>A (p.D223N) in the SCO2 gene in combination with a paternally inherited 87-kb deletion. As hypertrophic cardiomyopathy (HCMP) was not documented in the patient, this observation prompted us to compare his clinical features with all 44 reported SCO2 patients in the literature. Surprisingly, the review shows that HCMP was present in only about 50% of the SCO2 patients with non-neonatal onset. In the second patient, who had mitochondrial neurogastrointestinal encephalopathy (MNGIE), a maternally inherited 175-kb deletion and the paternally inherited point mutation c.261G>T (p.E87D) in the TYMP gene were identified. PMID:23838601

  12. Large copy number variations in combination with point mutations in the TYMP and SCO2 genes found in two patients with mitochondrial disorders.

    PubMed

    Vondráčková, Alžběta; Veselá, Kateřina; Kratochvílová, Hana; Kučerová Vidrová, Vendula; Vinšová, Kamila; Stránecký, Viktor; Honzík, Tomáš; Hansíková, Hana; Zeman, Jiří; Tesařová, Markéta

    2014-03-01

    Mitochondrial disorders are caused by defects in mitochondrial or nuclear DNA. Although the existence of large deletions in mitochondrial DNA (mtDNA) is well known, deletions affecting whole genes are not commonly described in patients with mitochondrial disorders. Based on the results of whole-genome analyses, copy number variations (CNVs) occur frequently in the human genome and may overlap with many genes associated with clinical phenotypes. We report the discovery of two large heterozygous CNVs on 22q13.33 in two patients with mitochondrial disorders. The first patient harboured a novel point mutation c.667G>A (p.D223N) in the SCO2 gene in combination with a paternally inherited 87-kb deletion. As hypertrophic cardiomyopathy (HCMP) was not documented in the patient, this observation prompted us to compare his clinical features with all 44 reported SCO2 patients in the literature. Surprisingly, the review shows that HCMP was present in only about 50% of the SCO2 patients with non-neonatal onset. In the second patient, who had mitochondrial neurogastrointestinal encephalopathy (MNGIE), a maternally inherited 175-kb deletion and the paternally inherited point mutation c.261G>T (p.E87D) in the TYMP gene were identified. PMID:23838601

  13. Mutations in GTPBP3 Cause a Mitochondrial Translation Defect Associated with Hypertrophic Cardiomyopathy, Lactic Acidosis, and Encephalopathy

    PubMed Central

    Kopajtich, Robert; Nicholls, Thomas J.; Rorbach, Joanna; Metodiev, Metodi D.; Freisinger, Peter; Mandel, Hanna; Vanlander, Arnaud; Ghezzi, Daniele; Carrozzo, Rosalba; Taylor, Robert W.; Marquard, Klaus; Murayama, Kei; Wieland, Thomas; Schwarzmayr, Thomas; Mayr, Johannes A.; Pearce, Sarah F.; Powell, Christopher A.; Saada, Ann; Ohtake, Akira; Invernizzi, Federica; Lamantea, Eleonora; Sommerville, Ewen W.; Pyle, Angela; Chinnery, Patrick F.; Crushell, Ellen; Okazaki, Yasushi; Kohda, Masakazu; Kishita, Yoshihito; Tokuzawa, Yoshimi; Assouline, Zahra; Rio, Marlène; Feillet, François; Mousson de Camaret, Bénédict; Chretien, Dominique; Munnich, Arnold; Menten, Björn; Sante, Tom; Smet, Joél; Régal, Luc; Lorber, Abraham; Khoury, Asaad; Zeviani, Massimo; Strom, Tim M.; Meitinger, Thomas; Bertini, Enrico S.; Van Coster, Rudy; Klopstock, Thomas; Rötig, Agnès; Haack, Tobias B.; Minczuk, Michal; Prokisch, Holger

    2014-01-01

    Respiratory chain deficiencies exhibit a wide variety of clinical phenotypes resulting from defective mitochondrial energy production through oxidative phosphorylation. These defects can be caused by either mutations in the mtDNA or mutations in nuclear genes coding for mitochondrial proteins. The underlying pathomechanisms can affect numerous pathways involved in mitochondrial physiology. By whole-exome and candidate gene sequencing, we identified 11 individuals from 9 families carrying compound heterozygous or homozygous mutations in GTPBP3, encoding the mitochondrial GTP-binding protein 3. Affected individuals from eight out of nine families presented with combined respiratory chain complex deficiencies in skeletal muscle. Mutations in GTPBP3 are associated with a severe mitochondrial translation defect, consistent with the predicted function of the protein in catalyzing the formation of 5-taurinomethyluridine (τm5U) in the anticodon wobble position of five mitochondrial tRNAs. All case subjects presented with lactic acidosis and nine developed hypertrophic cardiomyopathy. In contrast to individuals with mutations in MTO1, the protein product of which is predicted to participate in the generation of the same modification, most individuals with GTPBP3 mutations developed neurological symptoms and MRI involvement of thalamus, putamen, and brainstem resembling Leigh syndrome. Our study of a mitochondrial translation disorder points toward the importance of posttranscriptional modification of mitochondrial tRNAs for proper mitochondrial function. PMID:25434004

  14. The Mitochondrial Sulfur Dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 Is Required for Amino Acid Catabolism during Carbohydrate Starvation and Embryo Development in Arabidopsis1[C][W

    PubMed Central

    Krüßel, Lena; Junemann, Johannes; Wirtz, Markus; Birke, Hannah; Thornton, Jeremy D.; Browning, Luke W.; Poschet, Gernot; Hell, Rüdiger; Balk, Janneke; Braun, Hans-Peter; Hildebrandt, Tatjana M.

    2014-01-01

    The sulfur dioxygenase ETHYLMALONIC ENCEPHALOPATHY PROTEIN1 (ETHE1) catalyzes the oxidation of persulfides in the mitochondrial matrix and is essential for early embryo development in Arabidopsis (Arabidopsis thaliana). We investigated the biochemical and physiological functions of ETHE1 in plant metabolism using recombinant Arabidopsis ETHE1 and three transfer DNA insertion lines with 50% to 99% decreased sulfur dioxygenase activity. Our results identified a new mitochondrial pathway catalyzing the detoxification of reduced sulfur species derived from cysteine catabolism by oxidation to thiosulfate. Knockdown of the sulfur dioxygenase impaired embryo development and produced phenotypes of starvation-induced chlorosis during short-day growth conditions and extended darkness, indicating that ETHE1 has a key function in situations of high protein turnover, such as seed production and the use of amino acids as alternative respiratory substrates during carbohydrate starvation. The amino acid profile of mutant plants was similar to that caused by defects in the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase complex and associated dehydrogenases. Thus, in addition to sulfur amino acid catabolism, ETHE1 also affects the oxidation of branched-chain amino acids and lysine. PMID:24692429

  15. A new disease-related mutation for mitochondrial encephalopathy lactic acidosis and strokelike episodes (MELAS) syndrome affects the ND4 subunit of the respiratory complex I

    SciTech Connect

    Lertrit, P.; Noer, A.S.; Kapsa, R.; Marzuki, S. ); Jean-Francois, M.J.B.; Thyagarajan, D.; Byrne, E. ); Dennett, X. ); Lethlean, K. )

    1992-09-01

    The molecular lesions in two patients exhibiting classical clinical manifestations of MELAS (mitochondrial encephalopathy, lactic acidosis, and strokelike episodes) syndrome have been investigated. A recently reported disease-related A[yields]G base substitution at nt 3243 of the mtDNA, in the DHU loop of tRNA[sup Leu], was detected by restriction-enzyme analysis of the relevant PCR-amplified segment of the mtDNA of one patient but was not observed, by either restriction-enzyme analysis or nucleotide sequencing, in the other. To define the molecular lesion in the patient who does not have the A[yields]G base substitution at nt 3243, the total mitochondrial genome of the patient has been sequenced. An A[yields]G base substitution at nt 11084, leading to a Thr-to-Ala amino acid replacement in the ND4 subunit of the respiratory complex I, is suggested to be a disease-related mutation. 49 refs., 7 figs., 1 tab.

  16. Bezafibrate upregulates carnitine palmitoyltransferase II expression and promotes mitochondrial energy crisis dissipation in fibroblasts of patients with influenza-associated encephalopathy.

    PubMed

    Yao, Min; Yao, Dengbin; Yamaguchi, Miyoko; Chida, Junji; Yao, Dengfu; Kido, Hiroshi

    2011-11-01

    Influenza-associated encephalopathy (IAE) is characterized by persistently high fever, febrile convulsions, severe brain edema and high mortality. We reported previously that a large proportion of patients with disabling or fatal IAE exhibit a thermolabile phenotype of compound variants for [1055T>G/F352C] and [1102G>A/V368I] of carnitine palmitoyltransferase II (CPT II) and mitochondrial energy crisis during high fever. In the present study, we studied the effect of bezafibrate, a hypolipidemic pan-agonist of peroxisome proliferator-activated receptor (PPAR), on CPT II expression and mitochondrial energy metabolism in fibroblasts of IAE patients and wild type (WT) fibroblasts from a healthy volunteer at 37°C and 41°C. Although heat stress markedly upregulated CPT II, CPT IA and PPAR-δ mRNA expression levels, CPT II activity, β-oxidation and ATP levels in WT and IAE fibroblasts at 41°C were paradoxically downregulated probably due to the thermal instability of the corresponding enzymes. Bezafibrate significantly enhanced the expression levels of the above mRNAs and cellular functions of these enzymes in fibroblasts at 37°C. Bezafibrate-induced increase in CPT II activity also tended to restore the downregulated ATP levels, though moderately, and improved mitochondrial membrane potential even at 41°C to the levels at 37°C in fibroblasts of IAE patients. L-carnitine, a substrate of CPT II, boosted the effects of bezafibrate on cellular ATP levels in WT and IAE fibroblasts, even in severe IAE fibroblasts with thermolabile compound variations of F352C+V368I at 37°C and 41°C. The results suggest the potential usefulness of bezafibrate for the treatment of IAE. PMID:21816645

  17. Early Infantile Epileptic Encephalopathy in an STXBP1 Patient with Lactic Acidemia and Normal Mitochondrial Respiratory Chain Function

    PubMed Central

    Li, Dong; Bhoj, Elizabeth; McCormick, Elizabeth; Wang, Fengxiang; Snyder, James; Wang, Tiancheng; Zhao, Yan; Kim, Cecilia; Chiavacci, Rosetta; Tian, Lifeng; Falk, Marni J.; Hakonarson, Hakon

    2016-01-01

    A wide range of clinical findings have been associated with mutations in Syntaxin Binding Protein 1 (STXBP1), including multiple forms of epilepsy, nonsyndromic intellectual disability, and movement disorders. STXBP1 mutations have recently been associated with mitochondrial pathology, although it remains unclear if this phenotype is a part of the core feature for this gene disorder. We report a 7-year-old boy who presented for diagnostic evaluation of intractable epilepsy, episodic ataxia, resting tremor, and speech regression following a period of apparently normal early development. Mild lactic acidemia was detected on one occasion at the time of an intercurrent illness. Due to the concern for mitochondrial disease, ophthalmologic evaluation was performed that revealed bilateral midperiphery pigmentary mottling. Optical coherence tomography (OCT) testing demonstrated a bilaterally thickened ganglion cell layer in the perifovea. Skeletal muscle biopsy analysis showed no mitochondrial abnormalities or respiratory chain dysfunction. Exome sequencing identified a de novo c.1651C>T (p.R551C) mutation in STXBP1. Although mitochondrial dysfunction has been reported in some individuals, our proband had only mild lactic acidemia and no skeletal muscle tissue evidence of mitochondrial disease pathology. Thus, mitochondrial dysfunction is not an obligate feature of STXBP1 disease. PMID:27069701

  18. Toxic Encephalopathy

    PubMed Central

    Kim, Jae Woo

    2012-01-01

    This article schematically reviews the clinical features, diagnostic approaches to, and toxicological implications of toxic encephalopathy. The review will focus on the most significant occupational causes of toxic encephalopathy. Chronic toxic encephalopathy, cerebellar syndrome, parkinsonism, and vascular encephalopathy are commonly encountered clinical syndromes of toxic encephalopathy. Few neurotoxins cause patients to present with pathognomonic neurological syndromes. The symptoms and signs of toxic encephalopathy may be mimicked by many psychiatric, metabolic, inflammatory, neoplastic, and degenerative diseases of the nervous system. Thus, the importance of good history-taking that considers exposure and a comprehensive neurological examination cannot be overemphasized in the diagnosis of toxic encephalopathy. Neuropsychological testing and neuroimaging typically play ancillary roles. The recognition of toxic encephalopathy is important because the correct diagnosis of occupational disease can prevent others (e.g., workers at the same worksite) from further harm by reducing their exposure to the toxin, and also often provides some indication of prognosis. Physicians must therefore be aware of the typical signs and symptoms of toxic encephalopathy, and close collaborations between neurologists and occupational physicians are needed to determine whether neurological disorders are related to occupational neurotoxin exposure. PMID:23251840

  19. Hepatic Encephalopathy

    PubMed Central

    Bleibel, Wissam; Al-Osaimi, Abdullah M. S.

    2012-01-01

    Chronic liver disease and cirrhosis affect hundreds of millions of patients all over the world. The majority of patients with cirrhosis will eventually develop complications related to portal hypertension. One of these recurrent and difficult to treat complications is hepatic encephalopathy. Studies have indicated that overt hepatic encephalopathy affects 30 to 45% of patients with cirrhosis and a higher percentage may be affected by minimal degree of encephalopathy. All of these factors add to the impact of hepatic encephalopathy on the healthcare system and presents a major challenge to the gastroenterologist, hospitalist and primary care physician. PMID:23006457

  20. Metabolic Encephalopathy and Lipid Storage Myopathy Associated with a Presumptive Mitochondrial Fatty Acid Oxidation Defect in a Dog

    PubMed Central

    Biegen, Vanessa R.; McCue, John P.; Donovan, Taryn A.; Shelton, G. Diane

    2015-01-01

    A 1-year-old spayed female Shih Tzu presented for episodic abnormalities of posture and mentation. Neurological examination was consistent with a bilaterally symmetric multifocal encephalopathy. The dog had a waxing-and-waning hyperlactemia and hypoglycemia. Magnetic resonance imaging revealed bilaterally symmetric cavitated lesions of the caudate nuclei with less severe abnormalities in the cerebellar nuclei. Empirical therapy was unsuccessful, and the patient was euthanized. Post-mortem histopathology revealed bilaterally symmetric necrotic lesions of the caudate and cerebellar nuclei and multi-organ lipid accumulation, including a lipid storage myopathy. Malonic aciduria and ketonuria were found on urinary organic acid screen. Plasma acylcarnitine analysis suggested a fatty acid oxidation defect. Fatty acid oxidation disorders are inborn errors of metabolism documented in humans, but poorly described in dogs. Although neurological signs have been described in humans with this group of diseases, descriptions of advanced imaging, and histopathology are severely lacking. This report suggests that abnormalities of fatty acid metabolism may cause severe, bilateral gray matter necrosis, and lipid accumulation in multiple organs including the skeletal muscles, liver, and kidneys. Veterinarians should be aware that fatty acid oxidation disorders, although potentially fatal, may be treatable. A timely definitive diagnosis is essential in guiding therapy. PMID:26664991

  1. Myo-, neuro-, gastrointestinal encephalopathy (MNGIE syndrome) due to partial deficiency of cytochrome-c-oxidase. A new mitochondrial multisystem disorder.

    PubMed

    Bardosi, A; Creutzfeldt, W; DiMauro, S; Felgenhauer, K; Friede, R L; Goebel, H H; Kohlschütter, A; Mayer, G; Rahlf, G; Servidei, S

    1987-01-01

    A 42-year-old woman had a 10-year history of external ophthalmoplegia, malabsorption resulting in chronic malnutrition, muscle atrophy and polyneuropathy. Computer tomography revealed hypodensity of her cerebral white matter. A metabolic disturbance consisted of lactic acidosis after moderate glucose loads with increased excretion of hydroxybutyric and fumaric acids. Post-mortem studies revealed gastrointestinal scleroderma as the morphological manifestation of her malabsorption syndrome, ocular and skeletal myopathy with ragged red fibers, peripheral neuropathy, vascular abnormalities of meningeal and peripheral nerve vessels. Biochemical examination of the liver and muscle tissues revealed a partial defect of cytochrome-c-oxidase (complex IV of the respiratory chain). This mitochondrial multisystem disorder may represent a separate entity to be classified between the spectrum of myoencephalopathies and oculo-gastrointestinal muscular dystrophy. PMID:2823522

  2. Mutations of the SCO1 Gene in Mitochondrial Cytochrome c Oxidase Deficiency with Neonatal-Onset Hepatic Failure and Encephalopathy

    PubMed Central

    Valnot, Isabelle; Osmond, Sandrine; Gigarel, Nadine; Mehaye, Blandine; Amiel, Jeanne; Cormier-Daire, Valérie; Munnich, Arnold; Bonnefont, Jean-Paul; Rustin, Pierre; Rötig, Agnès

    2000-01-01

    Cytochrome c oxidase (COX) catalyzes both electron transfer from cytochrome c to molecular oxygen and the concomitant vectorial proton pumping across the inner mitochondrial membrane. Studying a large family with multiple cases of neonatal ketoacidotic comas and isolated COX deficiency, we have mapped the disease locus to chromosome 17p13.1, in a region encompassing two candidate genes involved in COX assembly—namely, SCO1 and COX10. Mutation screening revealed compound heterozygosity for SCO1 gene mutations in the patients. The mutated allele, inherited from the father, harbored a 2-bp frameshift deletion (ΔGA; nt 363–364) resulting in both a premature stop codon and a highly unstable mRNA. The maternally inherited mutation (C520T) changed a highly conserved proline into a leucine in the protein (P174L). This proline, adjacent to the CxxxC copper-binding domain of SCO1, is likely to play a crucial role in the tridimentional structure of the domain. Interestingly, the clinical presentation of SCO1-deficient patients markedly differs from that of patients harboring mutations in other COX assembly and/or maturation genes. PMID:11013136

  3. Hepatic encephalopathy.

    PubMed

    Córdoba, Juan; Mínguez, Beatriz

    2008-02-01

    Hepatic encephalopathy is a severe complication of cirrhosis that is related to the effects of ammonia. Analysis of interorgan ammonia trafficking has identified an important role of skeletal muscle in ammonia removal and has highlighted the importance of the nutritional status. Ammonia causes neurotransmitter abnormalities and induces injury to astrocytes that is partially mediated by oxidative stress. These disturbances lead to astrocyte swelling and brain edema, which appear to be involved in the pathogenesis of neurological manifestations. Inflammatory mediators worsen brain disturbances. New methods for assessing hepatic encephalopathy include clinical scales, neuropsychological tests, imaging of portal-systemic circulation, and magnetic resonance of the brain. Reappraisal of current therapy indicates the need for performing placebo-controlled trials and the lack of evidence for administering diets with restricted protein content. Liver transplant should be considered in selected patients with hepatic encephalopathy. Future prospects include new drugs that decrease plasma ammonia, measures to reduce brain edema, and liver-support devices. PMID:18293278

  4. Solvent encephalopathy.

    PubMed Central

    King, M D; Day, R E; Oliver, J S; Lush, M; Watson, J M

    1981-01-01

    Nineteen children aged 8-14 years were admitted over a six-year period with an acute encephalopathy due to toluene intoxication. Seven had a history of euphoria and hallucinations. The remainder presented with coma (4), ataxia (3), convulsions (3), and behaviour disturbance with diplopia (2), A history of glue sniffing was elicited in 14, but in the remainder toluene assay confirmed the diagnosis. Thirteen children recovered completely; five still had psychological impairment and personality change on discharge from hospital but were lost to follow-up, and one has a persistent cerebellar ataxia one year after the acute episode, despite absence of further exposure. Toluene inhalation is an important cause of encephalopathy in children and may lead to permanent neurological damage. Diagnosis is most important if further damage due to continued abuse is to be prevented, and toluene assay is a valuable aid to diagnosis. PMID:6790121

  5. A second MNGIE patient without typical mitochondrial skeletal muscle involvement.

    PubMed

    Cardaioli, Elena; Da Pozzo, Paola; Malfatti, Edoardo; Battisti, Carla; Gallus, Gian Nicola; Gaudiano, Carmen; Macucci, Marco; Malandrini, Alessandro; Margollicci, Maria; Rubegni, Anna; Dotti, Maria Teresa; Federico, Antonio

    2010-08-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease caused by mutations in the gene encoding thymidine phosphorylase (TYMP). Clinically, MNGIE is characterized by gastrointestinal dysmotility, cachexia, ptosis, ophthalmoparesis, peripheral neuropathy and leukoencephalopathy. Most MNGIE patients have signs of mitochondrial dysfunction in skeletal muscle at morphological and enzyme level, as well as mitochondrial DNA depletion, multiple deletions and point mutations. A case without mitochondrial skeletal muscle involvement and with a TYMP splice-acceptor site mutation (c. 215-1 G>C) has been reported. Here, we describe an Italian patient with the same mutation and without mitochondrial skeletal muscle involvement, suggesting a possible genotype-phenotype correlation. PMID:20232099

  6. [Hepatic encephalopathy].

    PubMed

    Jacques, Jérémie; Carrier, Paul; Debette-Gratien, Marilyne; Sobesky, Rodolphe; Loustaud-Ratti, Véronique

    2016-01-01

    Hepatic encephalopathy is a severe complication of liver cirrhosis and is an important therapeutic challenge, with a social and economic issue. If, now, the pathophysiology is not totally understood (main role of ammonia, but a better understanding of cerebral mechanisms), the clinical presentation is well-known. Some treatments are useful (disaccharides, treatment of the trigger) but their efficiency is limited. Nevertheless, the emergence of new treatments, such as non-absorbable antibiotics (rifaximin essentially), is an interesting therapeutic tool. PMID:26597584

  7. Hashimoto's encephalopathy.

    PubMed

    Schiess, Nicoline; Pardo, Carlos A

    2008-10-01

    Hashimoto's encephalopathy (HE) is a controversial neurological disorder that comprises a heterogenous group of neurological symptoms that manifest in patients with high titers of antithyroid antibodies. Clinical manifestations of HE may include encephalopathic features such as seizures, behavioral and psychiatric manifestations, movement disorders, and coma. Although it has been linked to cases of Hashimoto's thyroiditis or thyroid dysfunction, the most common immunological feature of HE is the presence of high titers of antithyroglobulin or anti-TPO (antimicrosomal) antibodies. At present, it is unclear whether antithyroid antibodies represent an immune epiphenomenon in a subset of patients with encephalopathic processes or they are really associated with pathogenic mechanisms of the disorder. The significance of classifying encephalopathies under the term HE will be determined in the future once the relevance of the role of antithyroid antibodies is demonstrated or dismissed by more detailed experimental and immunopathological studies. The responsiveness of HE to steroids or other therapies such as plasmapheresis supports the hypothesis that this is a disorder that involves immune pathogenic mechanisms. Further controlled studies of the use of steroids, plasmapheresis, or immunosuppressant medications are needed in the future to prove the concept of the pathogenic role of antithyroid antibodies in HE. PMID:18990131

  8. Mitochondrial syndromes with leukoencephalopathies.

    PubMed

    Wong, Lee-Jun C

    2012-02-01

    White matter involvement has recently been recognized as a common feature in patients with multisystem mitochondrial disorders that may be caused by molecular defects in either the mitochondrial genome or the nuclear genes. It was first realized in classical mitochondrial syndromes associated with mitochondrial DNA (mtDNA) mutations, such as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), Leigh's disease, and Kearns-Sayre's syndrome. Deficiencies in respiratory chain complexes I, II, IV, and V often cause Leigh's disease; most of them are due to nuclear defects that may lead to severe early-onset leukoencephalopathies. Defects in a group of nuclear genes involved in the maintenance of mtDNA integrity may also affect the white matter; for example, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) caused by thymidine phosphorylase deficiency, Navajo neurohepatopathy (NNH) due to MPV17 mutations, and Alpers syndrome due to defects in DNA polymerase gamma (POLG). More recently, leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) has been reported to be caused by autosomal recessive mutations in a mitochondrial aspartyl-tRNA synthetase, DARS2 gene. A patient with leukoencephalopathy and neurologic complications in addition to a multisystem involvement warrants a complete evaluation for mitochondrial disorders. A definite diagnosis may be achieved by molecular analysis of candidate genes based on the biochemical, clinical, and imaging results. PMID:22422207

  9. [Hepatic encephalopathy].

    PubMed

    Córdoba, Juan; Mur, Rafael Esteban

    2014-07-01

    Hepatic encephalopathy (EH) is a severe complication of hepatic cirrhosis that is characterized by multiple neuropsychiatric manifestations. EH is usually triggered by a precipitating factor and occurs in patients with severely impaired hepatic function. Minimal EH is characterized by minor cognitive impairments that are difficult to specify but represent a risk for the patients. The primary pathophysiological mechanism of EH is considered to be an increase in blood ammonia with an impairment in the patency of the blood-brainbarrier and its metabolism to glutamine in astrocytes. The diagnosis is clinical and neuroimaging techniques can be complementary. The diagnosis of minimal EH requires specific neurocognitive tests. The clinical evaluation should be directed towards identifying the trigger. Nonabsorbable disaccharides and rifaximin constitute the treatment of choice, along with prophylaxis for new episodes. PMID:25087716

  10. [Hepatic encephalopathy].

    PubMed

    Festi, Davide; Marasco, Giovanni; Ravaioli, Federico; Colecchia, Antonio

    2016-07-01

    Hepatic encephalopathy (HE) is a common complication of liver cirrhosis and it can manifest with a broad spectrum of neuropsychiatric abnormalities of varying severity, acuity and time course with important clinical implications. According to recent guidelines, HE has been classified into different types, depending on the severity of hepatic dysfunction, the presence of porto-systemic shunts and the number of previous episodes or persistent manifestations. From a clinical point of view, HE can be recognized as unimpaired, covert (that deals with minimal and grade 1 according to the grading of mental state), and overt (that is categorized from grade 2 to grade 4). Different and only partially known pathogenic mechanisms have been identified, comprising ammonia, inflammatory cytokines, benzodiazepine-like compounds and manganese deposition. Different therapeutic strategies are available for treating HE, in particular the overt HE, since covert HE needs to be managed case by case. Recognition and treatment of precipitating factors represent fundamental part of the management. The more effective treatments, which can be performed separately or combined, are represented by non-absorbable disaccharides (lactulose and lactitol) and the topic antibiotic rifaximin; other possible therapies, mainly used in patients non responders to previous treatments, are represented by branched chain amino acids and metabolic ammonia scavengers. PMID:27571468

  11. Autoimmune encephalopathies

    PubMed Central

    Leypoldt, Frank; Armangue, Thaís; Dalmau, Josep

    2014-01-01

    Over the last 10 years the continual discovery of novel forms of encephalitis associated with antibodies to cell-surface or synaptic proteins has changed the paradigms for diagnosing and treating disorders that were previously unknown or mischaracterized. We review here the process of discovery, the symptoms, and the target antigens of twelve autoimmune encephatilic disorders, grouped by syndromes and approached from a clinical perspective. Anti-NMDAR encephalitis, several subtypes of limbic encephalitis, stiff-person spectrum disorders, and other autoimmune encephalitides that result in psychosis, seizures, or abnormal movements are described in detail. We include a novel encephalopathy with prominent sleep dysfunction that provides an intriguing link between chronic neurodegeneration and cell-surface autoimmunity (IgLON5). Some of the caveats of limited serum testing are outlined. In addition, we review the underlying cellular and synaptic mechanisms that for some disorders confirm the antibody pathogenicity. The multidisciplinary impact of autoimmune encephalitis has been expanded recently by the discovery that herpes simplex encephalitis is a robust trigger of synaptic autoimmunity, and that some patients may develop overlapping syndromes, including anti-NMDAR encephalitis and neuromyelitis optica or other demyelinating diseases. PMID:25315420

  12. Pathogenesis of Hepatic Encephalopathy

    PubMed Central

    Ciećko-Michalska, Irena; Szczepanek, Małgorzata; Słowik, Agnieszka; Mach, Tomasz

    2012-01-01

    Hepatic encephalopathy can be a serious complication of acute liver failure and chronic liver diseases, predominantly liver cirrhosis. Hyperammonemia plays the most important role in the pathogenesis of hepatic encephalopathy. The brain-blood barrier disturbances, changes in neurotransmission, neuroinflammation, oxidative stress, GABA-ergic or benzodiazepine pathway abnormalities, manganese neurotoxicity, brain energetic disturbances, and brain blood flow abnormalities are considered to be involved in the development of hepatic encephalopathy. The influence of small intestine bacterial overgrowth (SIBO) on the induction of minimal hepatic encephalopathy is recently emphasized. The aim of this paper is to present the current views on the pathogenesis of hepatic encephalopathy. PMID:23316223

  13. Localized Cerebral Energy Failure in DNA Polymerase Gamma-Associated Encephalopathy Syndromes

    ERIC Educational Resources Information Center

    Tzoulis, Charalampos; Neckelmann, Gesche; Mork, Sverre J.; Engelsen, Bernt E.; Viscomi, Carlo; Moen, Gunnar; Ersland, Lars; Zeviani, Massimo; Bindoff, Laurence A.

    2010-01-01

    Mutations in the catalytic subunit of the mitochondrial DNA-polymerase gamma cause a wide spectrum of clinical disease ranging from infantile hepato-encephalopathy to juvenile/adult-onset spinocerebellar ataxia and late onset progressive external ophthalmoplegia. Several of these syndromes are associated with an encephalopathy that…

  14. Bovine Spongiform Encephalopathy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine spongiform encephalopathy (BSE), also referred to as “mad cow disease” is a chronic, non-febrile, neuro-degenerative disease affecting the central nervous system. The transmissible spongiform encephalopathies (TSEs) of domestic animals, of which BSE is a member includes scrapie of sheep...

  15. Hepatic encephalopathy: a review.

    PubMed

    Lizardi-Cervera, Javier; Almeda, Paloma; Guevara, Luis; Uribe, Misael

    2003-01-01

    Hepatic encephalopathy (HE) is a complication that presents in as many as 28% of patients with cirrhosis, and reported up to ten years after the diagnosis of cirrhosis. Commonly, it is observed in patients with severe hepatic failure and is characterized by neuropsychiatric manifestations that can range in severity from a mild alteration in mental state to a coma; additionally, some neuromuscular symptoms can be observed. This complication of either acute or chronic hepatic disease is the result of a diminished hepatic reservoir and inability to detoxify some toxins that originate in the bowel. Today, the role of astrocytes, specifically the Alzheimer type II cells, is known to be very important in the pathogenesis of the hepatic encephalopathy, and will be reviewed later. In conclusion, the objectives of this review are: To understand the pathogenesis of hepatic encephalopathy, To recognize the precipitating factors, as well as preventive measures for the development of the hepatic encephalopathy, To describe the new classification of hepatic encephalopathy and its clinical implications, To recognize the clinical manifestations and stages of the disease, To understand the main diagnostic tests used to detect the hepatic encephalopathy, To describe the main therapeutic treatments of hepatic encephalopathy. PMID:15115963

  16. Antibiotic-associated encephalopathy.

    PubMed

    Bhattacharyya, Shamik; Darby, R Ryan; Raibagkar, Pooja; Gonzalez Castro, L Nicolas; Berkowitz, Aaron L

    2016-03-01

    Delirium is a common and costly complication of hospitalization. Although medications are a known cause of delirium, antibiotics are an underrecognized class of medications associated with delirium. In this article, we comprehensively review the clinical, radiologic, and electrophysiologic features of antibiotic-associated encephalopathy (AAE). AAE can be divided into 3 unique clinical phenotypes: encephalopathy commonly accompanied by seizures or myoclonus arising within days after antibiotic administration (caused by cephalosporins and penicillin); encephalopathy characterized by psychosis arising within days of antibiotic administration (caused by quinolones, macrolides, and procaine penicillin); and encephalopathy accompanied by cerebellar signs and MRI abnormalities emerging weeks after initiation of antibiotics (caused by metronidazole). We correlate these 3 clinical phenotypes with underlying pathophysiologic mechanisms of antibiotic neurotoxicity. Familiarity with these types of antibiotic toxicity can improve timely diagnosis of AAE and prompt antibiotic discontinuation, reducing the time patients spend in the delirious state. PMID:26888997

  17. Mitochondrial encephalomyopathies.

    PubMed

    Lombes, A; Bonilla, E; Dimauro, S

    1989-01-01

    Increasingly numerous studies are being devoted to mitochondrial diseases, notably those which involve the neuromuscular system. Our knowledge and understanding of these diseases is progressing rapidly. We owe to Luft et al. (1962) the first description of this type of diseases. Their patient, a woman, presented with clinical symptoms suggestive of mitochondrial dysfunction, major histological abnormalities of skeletal muscle mitochondria and defective oxidative phosphorylation coupling clearly demonstrated in mitochondria isolated from muscle. This clinical, histological and biochemical triad led to the definition of mitochondrial myopathies. Subsequently, the triad was seldom encountered, and most mitochondrial myopathies were primarily defined by the presence of morphological abnormalities of muscle mitochondria. This review deals with the morphological, clinical, biochemical and genetic aspects of mitochondrial encephalomyopathies. The various morphological abnormalities of mitochondria are described. These are not specific of any particular disease. They may be present in some non-mitochondrial diseases and may be lacking in diseases due to specific defects of mitochondrial enzymes (e.g. carnitine palmityl-transferase or pyruvate dehydrogenase). The clinical classification of mitochondrial encephalomyopathies is discussed. There are two main schools of thought: the "lumpers" do not recognize specific syndromes within the spectrum of mitochondrial "cytopathies", the "splitters" try to identify specific syndromes while recognizing the existence of borderline cases. The following syndromes are described: chronic progressive external ophthalmoplegia (CPEO), Kearns-Sayre syndrome (KSS), MERRF syndrome (myoclonic epilepsy with ragged-red fibers), MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, stroke-like episodes) and Leigh and Alpers syndromes. The biochemical classification comprises five types of abnormalities: defects of transport

  18. Current pathogenetic aspects of hepatic encephalopathy and noncirrhotic hyperammonemic encephalopathy

    PubMed Central

    Cichoż-Lach, Halina; Michalak, Agata

    2013-01-01

    Hepatic encephalopathy is a medical phenomenon that is described as a neuropsychiatric manifestation of chronic or acute liver disease that is characterized by psychomotor, intellectual and cognitive abnormalities with emotional/affective and behavioral disturbances. This article focuses on the underlying mechanisms of the condition and the differences between hepatic encephalopathy and noncirrhotic hyperammonemic encephalopathy. Hepatic encephalopathy is a serious condition that can cause neurological death with brain edema and intracranial hypertension. It is assumed that approximately 60%-80% of patients with liver cirrhosis develop hepatic encephalopathy. This review explores the complex mechanisms that lead to hepatic encephalopathy. However, noncirrhotic hyperammonemic encephalopathy is not associated with hepatic diseases and has a completely different etiology. Noncirrhotic hyperammonemic encephalopathy is a severe occurrence that is connected with multiple pathogeneses. PMID:23326159

  19. Syndromes associated with mitochondrial DNA depletion

    PubMed Central

    2014-01-01

    Mitochondrial dysfunction accounts for a large group of inherited metabolic disorders most of which are due to a dysfunctional mitochondrial respiratory chain (MRC) and, consequently, deficient energy production. MRC function depends on the coordinated expression of both nuclear (nDNA) and mitochondrial (mtDNA) genomes. Thus, mitochondrial diseases can be caused by genetic defects in either the mitochondrial or the nuclear genome, or in the cross-talk between the two. This impaired cross-talk gives rise to so-called nuclear-mitochondrial intergenomic communication disorders, which result in loss or instability of the mitochondrial genome and, in turn, impaired maintenance of qualitative and quantitative mtDNA integrity. In children, most MRC disorders are associated with nuclear gene defects rather than alterations in the mtDNA itself. The mitochondrial DNA depletion syndromes (MDSs) are a clinically heterogeneous group of disorders with an autosomal recessive pattern of transmission that have onset in infancy or early childhood and are characterized by a reduced number of copies of mtDNA in affected tissues and organs. The MDSs can be divided into least four clinical presentations: hepatocerebral, myopathic, encephalomyopathic and neurogastrointestinal. The focus of this review is to offer an overview of these syndromes, listing the clinical phenotypes, together with their relative frequency, mutational spectrum, and possible insights for improving diagnostic strategies. PMID:24708634

  20. Mitochondrial diseases and epilepsy.

    PubMed

    Bindoff, Laurence A; Engelsen, Bernt A

    2012-09-01

    The mitochondrial respiratory chain is the final common pathway for energy production. Defects affecting this pathway can give rise to disease that presents at any age and affects any tissue. However, irrespective of genetic defect, epilepsy is common and there is a significant risk of status epilepticus. This review summarizes our current understanding of the epilepsy that occurs in mitochondrial disease, focusing on three of the most common disorders: mitochondrial myopathy encephalopathy, lactic acidosis and stroke-like episodes (MELAS), myoclonus epilepsy and ragged-red fibers (MERRF), and polymerase gamma (POLG) related disease. In addition, we review the pathogenesis and possible treatment of these disorders. PMID:22946726

  1. Thymidine phosphorylase deficiency causes MNGIE: an autosomal recessive mitochondrial disorder.

    PubMed

    Hirano, M; Martí, R; Spinazzola, A; Nishino, I; Nishigaki, Y

    2004-10-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder caused by mutations in the gene encoding thymidine phosphorylase (TP). The disease is characterized clinically by impaired eye movements, gastrointestinal dysmotility, cachexia, peripheral neuropathy, myopathy, and leukoencephalopathy. Molecular genetic studies of MNGIE patients' tissues have revealed multiple deletions, depletion, and site-specific point mutations of mitochondrial DNA. TP is a cytosolic enzyme required for nucleoside homeostasis. In MNGIE, TP activity is severely reduced and consequently levels of thymidine and deoxyuridine in plasma are dramatically elevated. We have hypothesized that the increased levels of intracellular thymidine and deoxyuridine cause imbalances of mitochondrial nucleotide pools that, in turn, lead to the mtDNA abnormalities. MNGIE was the first molecularly characterized genetic disorder caused by abnormal mitochondrial nucleoside/nucleotide metabolism. Future studies are likely to reveal further insight into this expanding group of diseases. PMID:15571233

  2. [Hashimoto's encephalopathy and autoantibodies].

    PubMed

    Yoneda, Makoto

    2013-04-01

    Encephalopathy occasionally occurs in association with thyroid disorders, but most of these are treatable. These encephalopathies include a neuropsychiatric disorder associated with hypothyroidism, called myxedema encephalopathy. Moreover, Hashimoto's encephalopathy (HE) has been recognized as a new clinical disease based on an autoimmune mechanism associated with Hashimoto's thyroiditis. Steroid treatment was successfully administered to these patients. Recently, we discovered that the serum autoantibodies against the NH2-terminal of α-enolase (NAE) are highly specific diagnostic biomarkers for HE. Further, we analyzed serum anti-NAE autoantibodies and the clinical features in many cases of HE from institutions throughout Japan and other countries. Approximately half of assessed HE patients carry anti-NAE antibodies. The age was widely distributed with 2 peaks (20-30 years and 50-70 years). Most HE patients were in euthyroid states, and all patients had anti-thyroid (TG) antibodies and anti-thyroid peroxidase (TPO) antibodies. Anti-TSH receptor (TSH-R) antibodies were observed in some cases. The common neuropsychiatry features are consciousness disturbance and psychosis, followed by cognitive dysfunction, involuntary movements, seizures, and ataxia. Abnormalities on electroencephalography (EEG) and decreased cerebral blood flow on brain SPECT were common findings, whereas abnormal findings on brain magnetic resonance imaging (MRI) were rare. HE patients have various clinical phenotypes such as the acute encephalopathy form, the chronic psychiatric form, and other particular clinical forms, including limbic encephalitis, progressive cerebellar ataxia, and Creutzfeldt-Jakob disease (CJD)-like form. The cerebellar ataxic form of HE clinically mimics spinocerebellar degeneration (SCD) and is characterized by the absence of nystagmus, absent or mild cerebellar atrophy, and lazy background activities on EEG. Taken together, these data suggest that the possibility of

  3. Nonalcoholic Wernicke's encephalopathy.

    PubMed

    Welsh, Amanda; Rogers, Peter; Clift, Fraser

    2016-07-01

    Wernicke's encephalopathy (WE) is a serious neurologic condition resulting from thiamine deficiency. The majority of cases involve alcoholism; however, nonalcohol-associated WE does occur and is under-recognized. We discuss a case of a 22-year-old man with a history of Crohn's disease who presented to our emergency department with multiple neurologic complaints related to WE. PMID:25985980

  4. [Bovine spongiform encephalopathy].

    PubMed

    Suárez Fernández, G

    2001-01-01

    An histórical and conceptual review is made about Bovine Spongiform Encephalopathy or mad cows disease and an epidemiological analysis as a present and future health problem. This analysis of BSE should not be negative, considering the truths that we know today. PMID:11783042

  5. Cognitive dysfunction in mitochondrial disorders.

    PubMed

    Finsterer, J

    2012-07-01

    Among the various central nervous system (CNS) manifestations of mitochondrial disorders (MIDs), cognitive impairment is increasingly recognized and diagnosed (mitochondrial cognitive dysfunction). Aim of the review was to summarize recent findings concerning the aetiology, pathogenesis, diagnosis and treatment of cognitive decline in MIDs. Among syndromic MIDs due to mitochondrial DNA (mtDNA) mutations, cognitive impairment occurs in patients with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes syndrome, myoclonus epilepsy with ragged-red fibres syndrome, mitochondrial chronic progressive external ophthalmoplegia, Kearns-Sayre syndrome, neuropathy, ataxia and retinitis pigmentosa syndrome and maternally inherited diabetes and deafness. Among syndromic MIDs due to nuclear DNA (nDNA) mutations, cognitive decline has been reported in myo-neuro-gastro-intestinal encephalopathy, mitochondrial recessive ataxia syndrome, spinocerebellar ataxia with encephalopathy, Mohr-Tranebjaerg syndrome, leuko-encephalopathy; brain and spinal cord involvement and lactic acidosis, CMT2, Wolfram syndrome, Wolf-Hirschhorn syndrome and Leigh syndrome. In addition to syndromic MIDs, a large number of non-syndromic MIDs due to mtDNA as well as nDNA mutations have been reported, which present with cognitive impairment as the sole or one among several other CNS manifestations of a MID. Delineation of mitochondrial cognitive impairment from other types of cognitive impairment is essential to guide the optimal management of these patients. Treatment of mitochondrial cognitive impairment is largely limited to symptomatic and supportive measures. Cognitive impairment may be a CNS manifestation of syndromic as well as non-syndromic MIDs. Correct diagnosis of mitochondrial cognitive impairment is a prerequisite for the optimal management of these patients. PMID:22335339

  6. KCNQ2 encephalopathy

    PubMed Central

    Millichap, John J.; Park, Kristen L.; Tsuchida, Tammy; Ben-Zeev, Bruria; Carmant, Lionel; Flamini, Robert; Joshi, Nishtha; Levisohn, Paul M.; Marsh, Eric; Nangia, Srishti; Narayanan, Vinodh; Ortiz-Gonzalez, Xilma R.; Patterson, Marc C.; Pearl, Phillip L.; Porter, Brenda; Ramsey, Keri; McGinnis, Emily L.; Taglialatela, Maurizio; Tracy, Molly; Tran, Baouyen; Venkatesan, Charu; Weckhuysen, Sarah

    2016-01-01

    Objective: To advance the understanding of KCNQ2 encephalopathy genotype–phenotype relationships and to begin to assess the potential of selective KCNQ channel openers as targeted treatments. Methods: We retrospectively studied 23 patients with KCNQ2 encephalopathy, including 11 treated with ezogabine (EZO). We analyzed the genotype–phenotype relationships in these and 70 previously described patients. Results: The mean seizure onset age was 1.8 ± 1.6 (SD) days. Of the 20 EEGs obtained within a week of birth, 11 showed burst suppression. When new seizure types appeared in infancy (15 patients), the most common were epileptic spasms (n = 8). At last follow-up, seizures persisted in 9 patients. Development was delayed in all, severely in 14. The KCNQ2 variants identified introduced amino acid missense changes or, in one instance, a single residue deletion. They were clustered in 4 protein subdomains predicted to poison tetrameric channel functions. EZO use (assessed by the treating physicians and parents) was associated with improvement in seizures and/or development in 3 of the 4 treated before 6 months of age, and 2 of the 7 treated later; no serious side effects were observed. Conclusions: KCNQ2 variants cause neonatal-onset epileptic encephalopathy of widely varying severity. Pathogenic variants in epileptic encephalopathy are clustered in “hot spots” known to be critical for channel activity. For variants causing KCNQ2 channel loss of function, EZO appeared well tolerated and potentially beneficial against refractory seizures when started early. Larger, prospective studies are needed to enable better definition of prognostic categories and more robust testing of novel interventions. Classification of evidence: This study provides Class IV evidence that EZO is effective for refractory seizures in patients with epilepsy due to KCNQ2 encephalopathy. PMID:27602407

  7. Inherited peripheral neuropathies due to mitochondrial disorders.

    PubMed

    Cassereau, J; Codron, P; Funalot, B

    2014-05-01

    Mitochondrial disorders (MIDs) are frequently responsible for neuropathies with variable severity. Mitochondrial diseases causing peripheral neuropathies (PNP) may be due to mutations of mitochondrial DNA (mtDNA), as is the case in MERRF and MELAS syndromes, or to mutations of nuclear genes. Secondary abnormalities of mtDNA (such as multiple deletions of muscle mtDNA) may result from mitochondrial disorders due to mutations in nuclear genes involved in mtDNA maintenance. This is the case in several syndromes caused by impaired mtDNA maintenance, such as Sensory Ataxic Neuropathy, Dysarthria and Ophthalmoplegia (SANDO) due to recessive mutations in the POLG gene, which encodes the catalytic subunit of mtDNA polymerase (DNA polymerase gamma), or Mitochondrial Neuro-Gastro-Intestinal Encephalomyopathy (MNGIE), due to recessive mutations in the TYMP gene, which encodes thymidine phosphorylase. The last years have seen a growing list of evidence demonstrating that mitochondrial bioenergetics and dynamics might be dysfunctional in axonal Charcot-Marie-Tooth disease (CMT2), and these mechanisms might present a common link between dissimilar CMT2-causing genes. PMID:24768438

  8. [Peripheral neuropathies due to mitochondrial disorders].

    PubMed

    Funalot, B

    2009-12-01

    Involvement of peripheral nerves is frequent in mitochondrial disorders but with variable severity. Mitochondrial diseases causing peripheral neuropathies (PN) may be due to mutations of mitochondrial DNA (mtDNA), as is the case in MERRF and MELAS syndromes, or to mutations of nuclear genes. Secondary abnormalities of mtDNA (such as multiple deletions of muscle mtDNA) may result from mitochondrial disorders due to mutations in nuclear genes involved in mtDNA maintenance. This is the case in several syndromes caused by impaired mtDNA maintenance, such as Sensory Ataxic Neuropathy, Dysarthria and Ophthalmoplegia (SANDO) due to recessive mutations in the POLG gene, which encodes the catalytic subunit of mtDNA polymerase (DNA polymerase gamma), or Mitochondrial Neuro-Gastro-Intestinal Encephalomyopathy (MNGIE), due to recessive mutations in the TYMP gene, which encodes thymidine phosphorylase. Genetically-determined PN due to mutations of mitofusin 2, a GTPase involved in the fusion of external mitochondrial membranes, were identified during the last few years. Characteristic ultrastructural lesions (abnormalities of axonal mitochondria) are observed on longitudinal sections of nerve biopsies in patients with PN due to mitofusin 2 mutations. PMID:19942242

  9. Thymidine phosphorylase mutations cause instability of mitochondrial DNA.

    PubMed

    Hirano, Michio; Lagier-Tourenne, Clotilde; Valentino, Maria L; Martí, Ramon; Nishigaki, Yutaka

    2005-07-18

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder characterized by ptosis and progressive external ophthalmoplegia, peripheral neuropathy, severe gastrointestinal dysmotility, cachexia and leukoencephalopathy. Muscle biopsies of MNGIE patients have revealed morphologically abnormal mitochondria and defects of respiratory chain enzymes. In addition, patients harbor depletion, multiple deletions, and point mutations of mitochondrial DNA (mtDNA). This disorder is caused by loss-of-function mutations in the gene encoding thymidine phosphorylase (TP) a cytosolic enzyme. In MNGIE patients, TP activity is very low or absent resulting in dramatically elevated levels of plasma thymidine and deoxyuridine. We have hypothesized that the increased levels of thymidine and deoxyuridine cause mitochondrial nucleotide pool imbalances that, in turn, generate mtDNA alterations. PMID:15975738

  10. [EEG manifestations in metabolic encephalopathy].

    PubMed

    Lin, Chou-Ching K

    2005-09-01

    Normal brain function depends on normal neuronal metabolism, which is closely related to systemic homeostasis of metabolites, such as glucose, electrolytes, amino acids and ammonia. "Metabolic encephalopathy" indicates diffuse brain dysfunction caused by various systemic derangements. Electroencephalogram (EEG) is widely used to evaluate metabolic encephalopathy since 1937, when Berger first observed slow brain activity induced by hypoglycemia. EEG is most useful in differentiating organic from psychiatric conditions, identifying epileptogenicity, and providing information about the degree of cortical or subcortical dysfunction. In metabolic encephalopathy, EEG evolution generally correlates well with the severity of encephalopathy. However, EEG has little specificity in differentiating etiologies in metabolic encephalopathy. For example, though triphasic waves are most frequently mentioned in hepatic encephalopathy, they can also be seen in uremic encephalopathy, or even in aged psychiatric patients treated with lithium. Spike-and-waves may appear in hyper- or hypo-glycemia, uremic encephalopathy, or vitamin deficiencies, etc. Common principles of EEG changes in metabolic encephalopathy are (1) varied degrees of slowing, (2) assorted mixtures of epileptic discharge, (3) high incidence of triphasic waves, and (4), as a rule, reversibility after treatment of underlying causes. There are some exceptions to the above descriptions in specific metabolic disorders and EEG manifestations are highly individualized. PMID:16252619

  11. Diets in Encephalopathy.

    PubMed

    Abdelsayed, George G

    2015-08-01

    As many as 80% of patients with end-stage liver disease and hepatic encephalopathy have significant protein-calorie malnutrition. Because of the severe hypercatabolic state of cirrhosis, the provision of liberal amounts of carbohydrate (at least 35 to 40 kcal/kg per day), and between 1.2 and 1.6 g/kg of protein is necessary. Protein restriction is not recommended. Branched-chain amino acid supplementation and vegetable protein are associated with improved outcomes. Dietary supplementation with vitamins, minerals (with the notable exception of zinc) and probiotics should be decided on a case-by-case basis. PMID:26195204

  12. Disorders of nuclear-mitochondrial intergenomic signaling.

    PubMed

    Spinazzola, Antonella; Zeviani, Massimo

    2005-07-18

    Depletion and multiple deletions of mitochondrial DNA (mtDNA) have been associated with a number of autosomal disorders classified as defects of nuclear-mitochondrial intergenomic signaling. The mendelian forms of progressive external ophthalmoplegia (PEO) are clinically and genetically heterogeneous disorders characterized by the accumulation of multiple deletions of mtDNA in postmitotic patient's tissues. Most of the autosomal dominant PEO (adPEO) families carry heterozygous mutations in either one of three genes: ANT1, Twinkle, and POLG1. Mutations in POLG1 can also cause autosomal recessive PEO (arPEO) and apparently sporadic cases. In addition, recessive POLG1 mutations are responsible for sensory-atactic neuropathy, dysarthria and ophthalmoplegia (SANDO), juvenile spino-cerebellar ataxia-epilepsy syndrome (SCAE) and Alpers-Huttenlocher hepatopathic poliodystrophy. Mutations in thymidine phosphorylase gene (TP) are linked to mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), an autosomal recessive disorder in which PEO is associated with gastrointestinal dysmotility and leukodystrophy. Finally, mitochondrial DNA depletion syndromes (MDS), defined by tissue-reduction in mtDNA copy number, have been linked to mutations in two genes involved in deoxyribonucleotide (dNTP) metabolism: thymidine kinase 2 (TK2) and deoxyguanosine kinase (DGUOK). PMID:15921863

  13. Treatment of epileptic encephalopathies.

    PubMed

    McTague, Amy; Cross, J Helen

    2013-03-01

    Epileptic encephalopathy is defined as a condition where the epileptic activity itself may contribute to the severe neurological and cognitive impairment seen, over and above that which would be expected from the underlying pathology alone. The epilepsy syndromes at high risk of this are a disparate group of conditions characterized by epileptic seizures that are difficult to treat and developmental delay. In this review, we discuss the ongoing debate regarding the significance of inter-ictal discharges and the impact of the seizures themselves on the cognitive delay or regression that is a common feature of these syndromes. The syndromes also differ in many ways and we provide a summary of the key features of the early-onset epileptic encephalopathies including Ohtahara and West syndromes in addition to later childhood-onset syndromes such as Lennox Gastaut and Doose syndromes. An understanding of the various severe epilepsy syndromes is vital to understanding the rationale for treatment. For example, the resolution of hypsarrhythmia in West syndrome is associated with an improvement in cognitive outcome and drives treatment choice, but the same cannot be applied to frequent inter-ictal discharges in Lennox Gastaut syndrome. We discuss the evidence base for treatment where it is available and describe current practice where it is not. For example, in West syndrome there is some evidence for preference of hormonal treatments over vigabatrin, although the choice and duration of hormonal treatment remains unclear. We describe the use of conventional and newer anti-epileptic medications in the various syndromes and discuss which medications should be avoided. Older possibly forgotten treatments such as sulthiame and potassium bromide also have a role in the severe epilepsies of childhood. We discuss hormonal treatment with particular focus on the treatment of West syndrome, continuous spike wave in slow wave sleep (CSWS)/electrical status epilepticus in slow wave

  14. [Prevention of hepatic encephalopathy].

    PubMed

    Morillas, Rosa M; Sala, Marga; Planas, Ramon

    2014-06-01

    Hepatic encephalopathy (HE) is a frequent complication of cirrhosis which, in addition to producing a great social impact, deteriorates the quality of life of patients and is considered a sign of advanced liver disease and therefore a clinical indication for liver transplant evaluation. Patients who have had episodes of HE have a high risk of recurrence. Thus, after the HE episode resolves, it is recommended: control and prevention of precipitating factors (gastrointestinal bleeding, spontaneous bacterial peritonitis, use of diuretics with caution, avoid nervous system depressant medications), continued administration of non-absorbable disaccharides such as lactulose or lactitol, few or non-absorbable antibiotics such as rifaximin and assess the need for a liver transplant as the presence of a HE episode carries a poor prognosis in cirrhosis. PMID:24480288

  15. Defects in Mitochondrial DNA Replication and Human Disease

    PubMed Central

    Copeland, William C.

    2011-01-01

    Mitochondrial DNA (mtDNA) is replicated by the DNA polymerase γ in concert with accessory proteins such as the mitochondrial DNA helicase, single stranded DNA binding protein, topoisomerase, and initiating factors. Nucleotide precursors for mtDNA replication arise from the mitochondrial salvage pathway originating from transport of nucleosides, or alternatively from cytoplasmic reduction of ribonucleotides. Defects in mtDNA replication or nucleotide metabolism can cause mitochondrial genetic diseases due to mtDNA deletions, point mutations, or depletion which ultimately cause loss of oxidative phosphorylation. These genetic diseases include mtDNA depletion syndromes (MDS) such as Alpers or early infantile hepatocerebral syndromes, and mtDNA deletion disorders, such as progressive external ophthalmoplegia (PEO), ataxia-neuropathy, or mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). This review focuses on our current knowledge of genetic defects of mtDNA replication (POLG, POLG2, C10orf2) and nucleotide metabolism (TYMP, TK2, DGOUK, and RRM2B) that cause instability of mtDNA and mitochondrial disease. PMID:22176657

  16. Alteration of nucleotide metabolism: a new mechanism for mitochondrial disorders.

    PubMed

    Martí, Ramon; Nishigaki, Yutaka; Vilá, Maya R; Hirano, Michio

    2003-07-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disease caused by loss-of-function mutations in the gene encoding thymidine phosphorylase (TP). TP deficiency alters the metabolism of the nucleosides thymidine and deoxyuridine, which, in turn, produces abnormalities of mitochondrial DNA (mtDNA) including depletion, deletions, and point mutations. MNGIE is the best characterized of the expanding number of mitochondrial disorders caused by alterations in the metabolism of nucleosides/nucleotides. Because mitochondria contain their own machinery for nucleoside and nucleotide metabolism and have physically separate nucleotide pools, it is not surprising that disorders of these pathways cause human diseases. Other diseases in this group include mtDNA depletion syndromes caused by mutations on the nuclear genes encoding the mitochondrial thymidine kinase and deoxyguanosine kinase; autosomal dominant progressive external ophthalmoplegia with multiple deletions of mtDNA due to mutations in the genes encoding the muscle-isoform of mitochondrial ADP/ATP translocator; and mitochondrial DNA depletion due to toxicities of nucleoside analogues. Mutations in the deoxynucleotide carrier, a transporter of deoxynucleoside diphosphates, have been identified as a cause of congenital microcephaly. However, alterations of mtDNA have not yet been established in this disorder. Future studies are likely to reveal additional diseases and provide further insight into this new subject. PMID:12940507

  17. The transmissible spongiform encephalopathies of livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal protein misfolding neurodegenerative diseases. TSEs have been described in several species including bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep and goats, chronic wasting disease (CWD) in cervids, tr...

  18. Sepsis Associated Encephalopathy

    PubMed Central

    Chaudhry, Neera; Duggal, Ashish Kumar

    2014-01-01

    Sepsis associated encephalopathy (SAE) is a common but poorly understood neurological complication of sepsis. It is characterized by diffuse brain dysfunction secondary to infection elsewhere in the body without overt CNS infection. The pathophysiology of SAE is complex and multifactorial including a number of intertwined mechanisms such as vascular damage, endothelial activation, breakdown of the blood brain barrier, altered brain signaling, brain inflammation, and apoptosis. Clinical presentation of SAE may range from mild symptoms such as malaise and concentration deficits to deep coma. The evaluation of cognitive dysfunction is made difficult by the absence of any specific investigations or biomarkers and the common use of sedation in critically ill patients. SAE thus remains diagnosis of exclusion which can only be made after ruling out other causes of altered mentation in a febrile, critically ill patient by appropriate investigations. In spite of high mortality rate, management of SAE is limited to treatment of the underlying infection and symptomatic treatment for delirium and seizures. It is important to be aware of this condition because SAE may present in early stages of sepsis, even before the diagnostic criteria for sepsis can be met. This review discusses the diagnostic approach to patients with SAE along with its epidemiology, pathophysiology, clinical presentation, and differential diagnosis. PMID:26556425

  19. [Posterior reversible encephalopathy syndrome].

    PubMed

    Fischer, M; Schmutzhard, E

    2016-06-01

    Posterior reversible encephalopathy syndrome refers to a neurological disorder characterized by headache, disorders of consciousness, visual disturbances, epileptic seizures, and subcortical vasogenic edema. About two thirds of patients develop neurological symptoms, which are associated with blood pressure fluctuations. One hypothesis is that hypertensive episodes cause autoregulatory failure, and values above the upper limit of cerebral autoregulation result in a breakthrough followed by hyperperfusion and blood-brain barrier dysfunction. In another hypothesis, endothelial dysfunction triggered by numerous factors including preeclampsia, immunosuppressive agents, chemotherapeutics, sepsis, or autoimmune disorders is thought to be the key pathomechanism. Endo- or exogenic toxic agents including pharmacological substances, cytokines, or bacterial toxins are supposed to trigger endothelial activation and dysfunction resulting in the release of vasoconstrictors, pro-inflammatory mediators, and vascular leakage. Diagnosis is usually based on clinical and neuroimaging findings that frequently show a bilateral, symmetric, and parietooccipital pattern. However, the diagnosis can often only be confirmed during the course of disease after excluding important differential diagnoses. Currently, there is no specific treatment available. Lowering of arterial blood pressure and eliminating the underlying cause usually leads to an improvement of clinical and neuroradiological findings. Admission to a critical care unit is required in about 40 % of patients due to complicating conditions including status epilepticus, cerebral vasoconstriction, ischemia, or intracerebral hemorrhage. Prognosis is favorable; in the majority of patients neurological deficits and imaging findings resolve completely. PMID:27272329

  20. Chronic traumatic encephalopathy.

    PubMed

    Yi, Juneyoung; Padalino, David J; Chin, Lawrence S; Montenegro, Philip; Cantu, Robert C

    2013-01-01

    Sports-related concussion has gained increased prominence, in part due to media coverage of several well-known athletes who have died from consequences of chronic traumatic encephalopathy (CTE). CTE was first described by Martland in 1928 as a syndrome seen in boxers who had experienced significant head trauma from repeated blows. The classic symptoms of impaired cognition, mood, behavior, and motor skills also have been reported in professional football players, and in 2005, the histopathological findings of CTE were first reported in a former National Football League (NFL) player. These finding were similar to Alzheimer's disease in some ways but differed in critical areas such as a predominance of tau protein deposition over amyloid. The pathophysiology is still unknown but involves a history of repeated concussive and subconcussive blows and then a lag period before CTE symptoms become evident. The involvement of excitotoxic amino acids and abnormal microglial activation remain speculative. Early identification and prevention of this disease by reducing repeated blows to the head has become a critical focus of current research. PMID:23314081

  1. Sepsis-Associated Encephalopathy

    PubMed Central

    Cotena, Simona; Piazza, Ornella

    2012-01-01

    Summary Sepsis-associated encephalopathy (SAE) is defined as a diffuse or multifocal cerebral dysfunction induced by the systemic response to the infection without clinical or laboratory evidence of direct brain infection. Its pathogenesis is multifactorial. SAE generally occurs early during severe sepsis and precedes multiple-organ failure. The most common clinical feature of SAE is the consciousness alteration which ranges from mildly reduced awareness to unresponsiveness and coma. Diagnosis of SAE is primarily clinical and depends on the exclusion of other possible causes of brain deterioration. Electroencephalography (EEG) is almost sensitive, but it is not specific for SAE. Computed Tomography (CT) head scan generally is negative in case of SAE, while Magnetic Resonance Imaging (MRI) can show brain abnormalities in case of SAE, but they are not specific for this condition. Somatosensitive Evoked Potentials (SEPs) are sensitive markers of developing cerebral dysfunction in sepsis. Cerebrospinal fluid (CBF) analysis is generally normal, a part an inconstant elevation of proteins concentration. S100B and NSE have been proposed like biomarkers for diagnosis of SAE, but the existing data are controversial. SAE is reversible even if survivors of severe sepsis have often long lasting or irreversible cognitive and behavioral sequel; however the presence of SAE can have a negative influence on survival. A specific therapy of SAE does not exist and the outcome depends on a prompt and appropriate treatment of sepsis as whole. PMID:23905041

  2. Non-Hyperammonemic valproate encephalopathy.

    PubMed

    Farooq, Omar; Zunga, Pervaiz M; Dar, Mohd I; Rather, Abdul Q; Rashid, Samia; Basu, Javid; Dar, Ishrat H; Ashraf, Mohd

    2014-04-01

    A 21-year-old male known case of primary hypothyroidism, Seizure disorder sequelae of an old trauma receiving sodium valproate, clobazam and phenobarbitone for control of Generalized tonic clonic seizures reported to neurology OPD with history of altered sensorium and gait unsteadiness for 1 week with history of hike in valproate dose 2 weeks before. On examination he was drowsy. Neurological examination was unremarkable except for gait unsteadiness and ataxia. Patient was admitted and evaluated for acute worsening. All (the) biochemical parameters including complete blood count, liver function tests, kidney function tests, routine urine examination, arterial blood gas analysis, blood and urine culture tests were normal. CSF analysis was also normal. Repeat MRI brain was also done which depicted all old changes with no fresh changes which will account for worsening of his sensorium. EEG was suggestive of diffuse encephalopathy. Thyroid function tests were also normal. Valproate encephalopathy was suspected and Valproate was empirically stopped and he was put on levetiracetam and phenytoin. His sensorium improved rapidly after stoppage of valproate with normalization of EEG. Serum valproate Levels were high with serum ammonia levels were in the normal range. We made the inference of nonhyperammoneamic valproate encephalopathy. This case highlights the existence of non-hyperammonemic valproate induced encephalopathy, suggesting mechanisms other than hyperammonemia responsible for this encephalopathy. PMID:25206067

  3. Diagnosis of minimal hepatic encephalopathy.

    PubMed

    Weissenborn, Karin

    2015-03-01

    Minimal hepatic encephalopathy (mHE) has significant impact upon a liver patient's daily living and health related quality of life. Therefore a majority of clinicians agree that mHE should be diagnosed and treated. The optimal means for diagnosing mHE, however, is controversial. This paper describes the currently most frequently used methods-EEG, critical flicker frequency, Continuous Reaction time Test, Inhibitory Control Test, computerized test batteries such as the Cognitive Drug Research test battery, the psychometric hepatic encephalopathy score (PHES) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)-and their pros and cons. PMID:26041959

  4. Hashimoto's Encephalopathy Presenting with Chorea.

    PubMed

    Sharan, Abhijeet; Sengupta, Sarbani; Mukhopadhyay, Sarmishtha; Ghosh, Bhaskar

    2015-09-01

    Hashimoto's encephalopathy (HE) is a steroid-responsive relapsing neuropsychiatric disorder associated with high titers of antithyroid antibody with or without thyroid dysfunction. We report a case of HE in a 78 year old female who developed sudden onset behavioral abnormalities associated with choreiform movement of extremities. All causes of vascular, infective, metabolic, autoimmune, paraneoplastic and toxic encephalopathy were excluded. Anti-thyroid peroxidase (anti-TPO) antibody was found to be raised with very high titre. A diagnosis of HE was made. Prompt treatment with high dose steroid led to dramatic improvement of symptoms including choreiform movement. PMID:27608878

  5. Defects in mitochondrial DNA replication and human disease.

    PubMed

    Copeland, William C

    2012-01-01

    Mitochondrial DNA (mtDNA) is replicated by the DNA polymerase g in concert with accessory proteins such as the mtDNA helicase, single stranded DNA binding protein, topoisomerase, and initiating factors. Nucleotide precursors for mtDNA replication arise from the mitochondrial salvage pathway originating from transport of nucleosides, or alternatively from cytoplasmic reduction of ribonucleotides. Defects in mtDNA replication or nucleotide metabolism can cause mitochondrial genetic diseases due to mtDNA deletions, point mutations, or depletion which ultimately cause loss of oxidative phosphorylation. These genetic diseases include mtDNA depletion syndromes such as Alpers or early infantile hepatocerebral syndromes, and mtDNA deletion disorders, such as progressive external ophthalmoplegia (PEO), ataxia-neuropathy, or mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). This review focuses on our current knowledge of genetic defects of mtDNA replication (POLG, POLG2, C10orf2) and nucleotide metabolism (TYMP, TK2, DGOUK, and RRM2B) that cause instability of mtDNA and mitochondrial disease. PMID:22176657

  6. Relapsing encephalopathy with cerebellar ataxia related to an ATP1A3 mutation.

    PubMed

    Dard, Rodolphe; Mignot, Cyril; Durr, Alexandra; Lesca, Gaetan; Sanlaville, Damien; Roze, Emmanuel; Mochel, Fanny

    2015-12-01

    ATP1A3, the gene encoding the α3-subunit of the Na(+) /K(+) -ATPase pump, has been involved in four clinical neurological entities: (1) alternating hemiplegia of childhood (AHC); (2) rapid-onset dystonia parkinsonism (RDP); (3) CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, sensorineural hearing loss) syndrome; and (4) early infantile epileptic encephalopathy. Here, we report on a 34-year-old female presenting with a new ATP1A3-related entity involving a relapsing encephalopathy characterized by recurrent episodes of cerebellar ataxia and altered consciousness during febrile illnesses. The term RECA is suggested - relapsing encephalopathy with cerebellar ataxia. The phenotype of this patient, resembling mitochondrial oxidative phosphorylation defects, emphasizes the possible role of brain energy deficiency in patients with ATP1A3 mutations. Rather than multiple overlapping syndromes, ATP1A3-related disorders might be seen as a phenotypic continuum. PMID:26400718

  7. Liver transplant in ethylmalonic encephalopathy: a new treatment for an otherwise fatal disease.

    PubMed

    Dionisi-Vici, Carlo; Diodato, Daria; Torre, Giuliano; Picca, Stefano; Pariante, Rosanna; Giuseppe Picardo, Sergio; Di Meo, Ivano; Rizzo, Cristiano; Tiranti, Valeria; Zeviani, Massimo; De Goyet, Jean De Ville

    2016-04-01

    Ethylmalonic encephalopathy is a fatal, rapidly progressive mitochondrial disorder caused byETHE1mutations, whose peculiar clinical and biochemical features are due to the toxic accumulation of hydrogen sulphide and of its metabolites, including thiosulphate. In mice with ethylmalonic encephalopathy, liver-targeted adeno-associated virus-mediatedETHE1gene transfer dramatically improved both clinical course and metabolic abnormalities. Reasoning that the same achievement could be accomplished by liver transplantation, we performed living donor-liver transplantation in an infant with ethylmalonic encephalopathy. Unlike the invariably progressive deterioration of the disease, 8 months after liver transplantation, we observed striking neurological improvement with remarkable achievements in psychomotor development, along with dramatic reversion of biochemical abnormalities. These results clearly indicate that liver transplantation is a viable therapeutic option for ETHE1 disease. PMID:26917598

  8. Human mitochondrial diseases caused by lack of taurine modification in mitochondrial tRNAs.

    PubMed

    Suzuki, Tsutomu; Nagao, Asuteka; Suzuki, Takeo

    2011-01-01

    Mitochondrial DNA mutations that cause mitochondrial dysfunction are responsible for a wide spectrum of human diseases, referred to as mitochondrial diseases. Pathogenic point mutations are found frequently in genes encoding mitochondrial (mt) tRNAs, indicating that impaired functioning of mutant mt tRNAs is the primary cause of mitochondrial dysfunction. Our previous studies revealed the absence of posttranscriptional taurine modification at the anticodon wobble uridine in mutant mt tRNAs isolated from cells derived from patients with two major classes of mitochondrial diseases, MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) and MERRF (myoclonus epilepsy associated with ragged red fibers). Defective taurine modification of the mutant mt tRNAs results in a deficiency in protein synthesis as the cognate codons of the mutant mt tRNA cannot be decoded. These findings represent the first evidence of a molecular pathogenesis caused by an RNA modification disorder. PMID:21957023

  9. Pharmacotherapy for hepatic encephalopathy.

    PubMed

    Phongsamran, Paula V; Kim, Jiwon W; Cupo Abbott, Jennifer; Rosenblatt, Angela

    2010-06-18

    Hepatic encephalopathy (HE) is a challenging clinical complication of liver dysfunction with a wide spectrum of neuropsychiatric abnormalities that range from mild disturbances in cognitive function and consciousness to coma and death. The pathogenesis of HE in cirrhosis is complex and multifactorial, but a key role is thought to be played by circulating gut-derived toxins of the nitrogenous compounds, most notably ammonia. Therapeutic treatment options for HE are currently limited and have appreciable risks and benefits associated with their use. Management of HE primarily involves avoidance of precipitating factors, limitation of dietary protein intake, and administration of various ammonia-lowering therapies such as non-absorbable disaccharides and select antimicrobial agents. Non-absorbable disaccharides, such as lactulose, have traditionally been regarded as first-line pharmacotherapy for patients with HE. However, multiple adverse events have been associated with their use. In addition, recent literature has questioned the true efficacy of the disaccharides for this indication. Neomycin, metronidazole and vancomycin may be used as alternative treatments for patients intolerant or unresponsive to non-absorbable disaccharides. Antimicrobials reduce bacterial production of ammonia and other bacteria-derived toxins through suppression of intestinal flora. Neomycin has been reported to be as effective as lactulose, and similar efficacy has been reported with vancomycin and metronidazole for the management of HE. However, the adverse effects frequently associated with these antimicrobials limit their use as first-line pharmacological agents. Neomycin is the most commonly used antimicrobial for HE and, although poorly absorbed, systemic exposure to the drug in sufficient amounts causes hearing loss and renal toxicity. Long-term neomycin therapy requires annual auditory testing and continuous monitoring of renal function. Long-term use of metronidazole has been

  10. GLUTAMINE IN THE PATHOGENESIS OF HEPATIC ENCEPHALOPATHY: THE TROJAN HORSE HYPOTHESIS REVISITED

    PubMed Central

    Rama Rao, Kakulavarapu V.; Norenberg, Michael D.

    2016-01-01

    Hepatic encephalopathy (HE) is major neuropsychiatric disorder occurring in patients with severe liver disease and ammonia is generally considered to represent the major toxin responsible for this condition. Ammonia in brain is chiefly metabolized (“detoxified”) to glutamine in astrocytes due to predominant localization of glutamine synthetase in these cells. While glutamine has long been considered innocuous, a deleterious role more recently has been attributed to this amino acid. This article reviews the mechanisms by which glutamine contributes to the pathogenesis of HE, how glutamine is transported into mitochondria and subsequently hydrolyzed leading to high levels of ammonia, the latter triggering oxidative and nitrative stress, the mitochondrial permeability transition and mitochondrial injury, a sequence of events we have collectively termed as the Trojan horse hypothesis of hepatic encephalopathy. PMID:23277414

  11. [Wernicke encephalopathy accompanying linitis plastica].

    PubMed

    Soós, Zsuzsanna; Salamon, Mónika; Oláh, Roland; Czégeni, Anna; Salamon, Ferenc; Folyovich, András; Winkler, Gábor

    2014-01-01

    Wernicke encephalopathy (or Wernicke-Korsakoff encephalopathy) is a rarely diagnosed neurological disorder, which is caused by vitamin B1 deficiency. In the classical form it is characterized by a typical triad (confusion, oculomotor disturbance and ataxia), however, in the majority of the cases only confusion is present. It can be frequently observed in subjects with chronic alcohol consumption, but it may accompany different pathological states of which end stage malignant diseases are the most importants, where confusion may have different backgrounds. The authors present the case of an old male patient with advanced gastric cancer recognised and treated vitamin B1 deficiency, and they draw attention to difficulties of the diagnosis of Wernicke's disease. PMID:24379094

  12. [CLINICAL ASPECTS OF SEPTIC ENCEPHALOPATHY].

    PubMed

    Fesenko, O V; Sinopal'nikov, A I; Filatov, V V; Danishevsky, S V; Styrt, E A

    2016-01-01

    Septic encephalopathy is a form of general cerebral dysfunction caused by a systemic inflammatory reaction. Its investigation encounters enormous difficulties for the lack of reliable biological markers of neuronal lesions and methods for the evaluation of consciousness in severely ill patients. Hence, the importance of correct clinical interpretation of the character and magnitude of CNS activity. Examples are presented demonstrating the difficulty of interpreting disorders in CNS activity associated with evere community-acquired pneumonia. PMID:27172727

  13. [Imaging in acute toxic encephalopathy].

    PubMed

    Dietemann, J-L; Botelho, C; Nogueira, T; Vargas, M I; Audibert, C; Abu Eid, M; Bogorin, A; Bernardo, R; Jacques, C; Kremer, S; Zöllner, G

    2004-09-01

    Neuroimaging, particularly MR imaging, plays a major role for the diagnosis of many acute toxic encephalopathies. Toxic disorders are related to drugs (immunosuppressive agents, chemotherapeutic agents, anti-epileptic drugs, heroin...), to metals (lead, manganese, mercury...), and to industrial and environmental chemicals (solvent, carbon monoxide...). MR imaging with diffusion and perfusion imaging provides information regarding brain lesions induced by the toxic agents (vasogenic edema, cytotoxic edema, infarction, hemorrhage, demyelination...). PMID:15545943

  14. Metabolic Causes of Epileptic Encephalopathy

    PubMed Central

    Pearl, Phillip L.

    2013-01-01

    Epileptic encephalopathy can be induced by inborn metabolic defects that may be rare individually but in aggregate represent a substantial clinical portion of child neurology. These may present with various epilepsy phenotypes including refractory neonatal seizures, early myoclonic encephalopathy, early infantile epileptic encephalopathy, infantile spasms, and generalized epilepsies which in particular include myoclonic seizures. There are varying degrees of treatability, but the outcome if untreated can often be catastrophic. The importance of early recognition cannot be overemphasized. This paper provides an overview of inborn metabolic errors associated with persistent brain disturbances due to highly active clinical or electrographic ictal activity. Selected diseases are organized by the defective molecule or mechanism and categorized as small molecule disorders (involving amino and organic acids, fatty acids, neurotransmitters, urea cycle, vitamers and cofactors, and mitochondria) and large molecule disorders (including lysosomal storage disorders, peroxisomal disorders, glycosylation disorders, and leukodystrophies). Details including key clinical features, salient electrophysiological and neuroradiological findings, biochemical findings, and treatment options are summarized for prominent disorders in each category. PMID:23762547

  15. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats.

    PubMed

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨ m ), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress. PMID:26180820

  16. Avocado Oil Improves Mitochondrial Function and Decreases Oxidative Stress in Brain of Diabetic Rats

    PubMed Central

    Ortiz-Avila, Omar; Esquivel-Martínez, Mauricio; Olmos-Orizaba, Berenice Eridani; Saavedra-Molina, Alfredo; Rodriguez-Orozco, Alain R.; Cortés-Rojo, Christian

    2015-01-01

    Diabetic encephalopathy is a diabetic complication related to the metabolic alterations featuring diabetes. Diabetes is characterized by increased lipid peroxidation, altered glutathione redox status, exacerbated levels of ROS, and mitochondrial dysfunction. Although the pathophysiology of diabetic encephalopathy remains to be clarified, oxidative stress and mitochondrial dysfunction play a crucial role in the pathogenesis of chronic diabetic complications. Taking this into consideration, the aim of this work was to evaluate the effects of 90-day avocado oil intake in brain mitochondrial function and oxidative status in streptozotocin-induced diabetic rats (STZ rats). Avocado oil improves brain mitochondrial function in diabetic rats preventing impairment of mitochondrial respiration and mitochondrial membrane potential (ΔΨm), besides increasing complex III activity. Avocado oil also decreased ROS levels and lipid peroxidation and improved the GSH/GSSG ratio as well. These results demonstrate that avocado oil supplementation prevents brain mitochondrial dysfunction induced by diabetes in association with decreased oxidative stress. PMID:26180820

  17. Rifaximin in the treatment of hepatic encephalopathy

    PubMed Central

    Iadevaia, Maddalena Diana; Prete, Anna Del; Cesaro, Claudia; Gaeta, Laura; Zulli, Claudio; Loguercio, Carmelina

    2011-01-01

    Hepatic encephalopathy is a challenging complication in patients with advanced liver disease. It can be defined as a neuropsychiatric syndrome caused by portosystemic venous shunting, ranging from minimal to overt hepatic encephalopathy or coma. Its pathophysiology is still unclear, although increased levels of ammonia play a key role. Diagnosis of hepatic encephalopathy is currently based on specific tests evaluating the neuropsychiatric state of patients and their quality of life; the severity of hepatic encephalopathy is measured by the West Haven criteria. Treatment of hepatic encephalopathy consists of pharmacological and corrective measures, as well as nutritional interventions. Rifaximin received approval for the treatment of hepatic encephalopathy in 2010 because of its few side effects and pharmacological benefits. The aim of this work is to review the use and efficacy of rifaximin both in acute and long-term management of hepatic encephalopathy. Treatment of overt hepatic encephalopathy involves management of the acute episode as well as maintenance of remission in those patients who have previously experienced an episode, in order to improve their quality of life. The positive effect of rifaximin in reducing health care costs is also discussed. PMID:24367227

  18. Rifaximin in the treatment of hepatic encephalopathy.

    PubMed

    Iadevaia, Maddalena Diana; Prete, Anna Del; Cesaro, Claudia; Gaeta, Laura; Zulli, Claudio; Loguercio, Carmelina

    2011-01-01

    Hepatic encephalopathy is a challenging complication in patients with advanced liver disease. It can be defined as a neuropsychiatric syndrome caused by portosystemic venous shunting, ranging from minimal to overt hepatic encephalopathy or coma. Its pathophysiology is still unclear, although increased levels of ammonia play a key role. Diagnosis of hepatic encephalopathy is currently based on specific tests evaluating the neuropsychiatric state of patients and their quality of life; the severity of hepatic encephalopathy is measured by the West Haven criteria. Treatment of hepatic encephalopathy consists of pharmacological and corrective measures, as well as nutritional interventions. Rifaximin received approval for the treatment of hepatic encephalopathy in 2010 because of its few side effects and pharmacological benefits. The aim of this work is to review the use and efficacy of rifaximin both in acute and long-term management of hepatic encephalopathy. Treatment of overt hepatic encephalopathy involves management of the acute episode as well as maintenance of remission in those patients who have previously experienced an episode, in order to improve their quality of life. The positive effect of rifaximin in reducing health care costs is also discussed. PMID:24367227

  19. Altered Sulfide (H2S) Metabolism in Ethylmalonic Encephalopathy

    PubMed Central

    Tiranti, Valeria; Zeviani, Massimo

    2013-01-01

    Hydrogen sulfide (sulfide, H2S) is a colorless, water-soluble gas with a typical smell of rotten eggs. In the past, it has been investigated for its role as a potent toxic gas emanating from sewers and swamps or as a by-product of industrial processes. At high concentrations, H2S is a powerful inhibitor of cytochrome c oxidase; in trace amounts, it is an important signaling molecule, like nitric oxide (NO) and carbon monoxide (CO), together termed “gasotransmitters.” This review will cover the physiological role and the pathogenic effects of H2S, focusing on ethylmalonic encephalopathy, a human mitochondrial disorder caused by genetic abnormalities of sulfide metabolism. We will also discuss the options that are now conceivable for preventing genetically driven chronic H2S toxicity, taking into account that a complete understanding of the physiopathology of H2S has still to be achieved. PMID:23284046

  20. Current understanding and neurobiology of epileptic encephalopathies.

    PubMed

    Auvin, Stéphane; Cilio, Maria Roberta; Vezzani, Annamaria

    2016-08-01

    Epileptic encephalopathies are a group of diseases in which epileptic activity itself contributes to severe cognitive and behavioral impairments above and beyond what might be expected from the underlying pathology alone. These impairments can worsen over time. This concept has been continually redefined since its introduction. A few syndromes are considered epileptic encephalopathies: early myoclonic encephalopathy and Ohtahara syndrome in the neonatal period, epilepsy of infancy with migrating focal seizures, West syndrome or infantile spasms, Dravet syndrome during infancy, Lennox-Gastaut syndrome, epileptic encephalopathy with continuous spikes-and-waves during sleep, and Landau-Kleffner syndrome during childhood. The inappropriate use of this term to refer to all severe epilepsy syndromes with intractable seizures and severe cognitive dysfunction has led to confusion regarding the concept of epileptic encephalopathy. Here, we review our current understanding of those epilepsy syndromes considered to be epileptic encephalopathies. Genetic studies have provided a better knowledge of neonatal and infantile epilepsy syndromes, while neuroimaging studies have shed light on the underlying causes of childhood-onset epileptic encephalopathies such as Lennox-Gastaut syndrome. Apart from infantile spasm models, we lack animal models to explain the neurobiological mechanisms at work in these conditions. Experimental studies suggest that neuroinflammation may be a common neurobiological pathway that contributes to seizure refractoriness and cognitive involvement in the developing brain. PMID:26992889

  1. Paroxysmal Amnesia Attacks due to Hashimoto's Encephalopathy

    PubMed Central

    Nar Senol, Pelin; Bican Demir, Aylin; Bora, Ibrahim; Bakar, Mustafa

    2016-01-01

    Hashimoto's encephalopathy is a rare disease which is thought to be autoimmune and steroid responsive. The syndrome is characterized by cognitive impairment, encephalopathy, psychiatric symptoms, and seizures associated with increased level of anti-thyroid antibodies. The exact pathophysiology underlying cerebral involvement is still lesser known. Although symptoms suggest a nonlesional encephalopathy in most of the cases, sometimes the clinical appearance can be subtle and may not respond to immunosuppressants or immunomodulatory agents. Here we report a case who presented with drowsiness and amnestic complaints associated with paroxysmal electroencephalography (EEG) abnormalities which could be treated only with an antiepileptic drug. PMID:27034679

  2. Encephalopathy

    MedlinePlus

    ... pressure in the skull, prolonged exposure to toxic elements (including solvents, drugs, radiation, paints, industrial chemicals, and certain metals), chronic progressive trauma, poor nutrition, ...

  3. Treatment of Overt Hepatic Encephalopathy.

    PubMed

    Sussman, Norman L

    2015-08-01

    Hepatic encephalopathy (HE) is defined by an altered mental status in the setting of portosystemic shunting, with or without cirrhosis. The basis of HE is probably multi-factorial, but increased ammonia delivery to the brain is thought to play a pivotal role. Medical therapies have typically focused on reducing blood ammonia concentrations. These measures are moderately effective, but further improvements will require identification of new therapeutic targets. Two medications, lactulose and rifaximin, are currently approved for the treatment of HE in the USA - new compounds are available off-label, and are in clinical trials. The presence of HE is associated with a higher risk of death in cirrhotic patients. Liver transplantation typically cures HE, but HE does not increase the MELD score, and therefore does not contribute to the likelihood of liver transplantation. PMID:26195208

  4. Suicide and Chronic Traumatic Encephalopathy.

    PubMed

    Iverson, Grant L

    2016-01-01

    For nearly 80 years, suicidality was not considered to be a core clinical feature of chronic traumatic encephalopathy (CTE). In recent years, suicide has been widely cited as being associated with CTE, and now depression has been proposed to be one of three core diagnostic features alongside cognitive impairment and anger control problems. This evolution of the clinical features has been reinforced by thousands of media stories reporting a connection between mental health problems in former athletes and military veterans, repetitive neurotrauma, and CTE. At present, the science underlying the causal assumption between repetitive neurotrauma, depression, suicide, and the neuropathology believed to be unique to CTE is inconclusive. Epidemiological evidence indicates that former National Football League players, for example, are at lower, not greater, risk for suicide than men in the general population. This article aims to discuss the critical issues and literature relating to these possible relationships. PMID:26449269

  5. Posterior Reversible Encephalopathy Syndrome in ALL.

    PubMed

    Millichap, J Gordon

    2015-07-01

    Investigators from Soochow University, Suzhou, China, studied the possible pathogenetic mechanisms and treatment of posterior reversible encephalopathy syndrome (PRES) observed in 11 cases of pediatric acute lymphoblastic leukemia (ALL) after induction chemotherapy. PMID:26933594

  6. Bovine Spongiform Encephalopathy: Atypical Pros and Cons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transmissible spongiform encephalopathies (TSEs) are fatal neurologic diseases that affect several mammalian species including human beings. Four animal TSE agents have been reported: scrapie of sheep and goats; chronic wasting disease (CWD) of deer, elk, and moose; transmissible mink encephalopath...

  7. Neuroimaging in Neonatal Hypoxic Ischemic Encephalopathy.

    PubMed

    Krishnan, Pradeep; Shroff, Manohar

    2016-09-01

    Magnetic resonance (MR) imaging is emerging as one of the most important tools in identifying the etiology of neonatal encephalopathy as well as in predicting long-term outcomes. This makes it imperative to have a broader understanding of normal myelination of the neonatal brain on MR imaging and to be familiar with the spectrum of imaging features in ischemic and non-ischemic neonatal encephalopathy. Hypoxic ischemic injury (HIE) is one of the most common causes of neonatal encephalopathy and imaging appearances are influenced by factors such as the stage of maturation of the neonatal brain and severity as well as duration of ischemic insult. Other common causes of neonatal encephalopathy include infectious diseases, congenital disorders and inborn errors of metabolism. PMID:26909496

  8. Gut microbiota and hepatic encephalopathy.

    PubMed

    Dhiman, Radha K

    2013-06-01

    There is a strong relationship between liver and gut; while the portal venous system receives blood from the gut, and its contents may affect liver functions, liver in turn, affects intestinal functions through bile secretion. There is robust evidence that the pathogenesis of hepatic encephalopathy (HE) is linked to alterations in gut microbiota and their by-products such as ammonia, indoles, oxindoles, endotoxins, etc. In the setting of intestinal barrier and immune dysfunction, these by-products are involved in the pathogenesis of complications of liver cirrhosis including HE and systemic inflammation plays an important role. Prebiotics, probiotics and synbiotics may exhibit efficacy in the treatment of HE by modulating the gut flora. They improve derangement in flora by decreasing the counts of pathogenic bacteria and thus improving the endotoxemia, HE and the liver disease. Current evidence suggest that the trials evaluating the role of probiotics in the treatment of HE are of not high quality and all trials had high risk of bias and high risk of random errors. Therefore, the use of probiotics for patients with HE cannot be currently recommended. Further RCTs are required. This review summarizes the main literature findings about the relationships between gut flora and HE, both in terms of the pathogenesis and the treatment of HE. PMID:23463489

  9. Chronic Traumatic Encephalopathy: A Review

    PubMed Central

    Saulle, Michael; Greenwald, Brian D.

    2012-01-01

    Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disease that is a long-term consequence of single or repetitive closed head injuries for which there is no treatment and no definitive pre-mortem diagnosis. It has been closely tied to athletes who participate in contact sports like boxing, American football, soccer, professional wrestling and hockey. Risk factors include head trauma, presence of ApoE3 or ApoE4 allele, military service, and old age. It is histologically identified by the presence of tau-immunoreactive NFTs and NTs with some cases having a TDP-43 proteinopathy or beta-amyloid plaques. It has an insidious clinical presentation that begins with cognitive and emotional disturbances and can progress to Parkinsonian symptoms. The exact mechanism for CTE has not been precisely defined however, research suggest it is due to an ongoing metabolic and immunologic cascade called immunoexcitiotoxicity. Prevention and education are currently the most compelling way to combat CTE and will be an emphasis of both physicians and athletes. Further research is needed to aid in pre-mortem diagnosis, therapies, and support for individuals and their families living with CTE. PMID:22567320

  10. Clinical Neurophysiology of Hepatic Encephalopathy

    PubMed Central

    Amodio, Piero; Montagnese, Sara

    2015-01-01

    Background/Objectives Hepatic encephalopathy (HE) has relevant impact on the quality of life of patients and their caregivers and causes relevant costs because of hospitalizations and work days lost. Its quantification is important to perform adequate clinical trials on this relevant complication of cirrhosis and portal-systemic shunting. Clinical neurophysiology, which detects functional alterations of the nervous system, has been applied to the study of HE for over 60 years. This review aims at summarizing and clarifying the role of neurophysiologic techniques in the study of HE. Methods A narrative review was performed aiming at interpreting the cited papers and the techniques on the basis of their physiological and pathophysiological meaning. Results The potential role of EEG, quantified EEG, evoked potentials—both exogenous, endogenous and motor—have been clarified to the reader that may be unfamiliar with neurophysiology. Conclusions The EEG, reflecting the oscillatory changes of neural network is the preferable tool to detect and monitor HE, with the exception of its most severe stage, when EEG flattens. SSEP and MEP have indication to detect and monitor transmission alterations that are likely related to myelin changes and microedema. PMID:26041960

  11. Hepatic encephalopathy: An approach to its multiple pathophysiological features.

    PubMed

    Perazzo, Juan Carlos; Tallis, Silvina; Delfante, Amalia; Souto, Pablo Andrés; Lemberg, Abraham; Eizayaga, Francisco Xavier; Romay, Salvador

    2012-03-27

    Hepatic encephalopathy (HE) is a neuropsychiatric complex syndrome, ranging from subtle behavioral abnormalities to deep coma and death. Hepatic encephalopathy emerges as the major complication of acute or chronic liver failure. Multiplicity of factors are involved in its pathophysiology, such as central and neuromuscular neurotransmission disorder, alterations in sleep patterns and cognition, changes in energy metabolism leading to cell injury, an oxidative/nitrosative state and a neuroinflammatory condition. Moreover, in acute HE, a condition of imminent threat of death is present due to a deleterious astrocyte swelling. In chronic HE, changes in calcium signaling, mitochondrial membrane potential and long term potential expression, N-methyl-D-aspartate-cGMP and peripheral benzodiazepine receptors alterations, and changes in the mRNA and protein expression and redistribution in the cerebral blood flow can be observed. The main molecule indicated as responsible for all these changes in HE is ammonia. There is no doubt that ammonia, a neurotoxic molecule, triggers or at least facilitates most of these changes. Ammonia plasma levels are increased two- to three-fold in patients with mild to moderate cirrhotic HE and up to ten-fold in patients with acute liver failure. Hepatic and inter-organ trafficking of ammonia and its metabolite, glutamine (GLN), lead to hyperammonemic conditions. Removal of hepatic ammonia is a differentiated work that includes the hepatocyte, through the urea cycle, converting ammonia into GLN via glutamine synthetase. Under pathological conditions, such as liver damage or liver blood by-pass, the ammonia plasma level starts to rise and the risk of HE developing is high. Knowledge of the pathophysiology of HE is rapidly expanding and identification of focally localized triggers has led the development of new possibilities for HE to be considered. This editorial will focus on issues where, to the best of our knowledge, more research is needed in

  12. ETHE1 mutations are specific to ethylmalonic encephalopathy

    PubMed Central

    Tiranti, V; Briem, E; Lamantea, E; Mineri, R; Papaleo, E; De Gioia, L; Forlani, F; Rinaldo, P; Dickson, P; Abu‐Libdeh, B; Cindro‐Heberle, L; Owaidha, M; Jack, R M; Christensen, E; Burlina, A; Zeviani, M

    2006-01-01

    Mutations in ETHE1, a gene located at chromosome 19q13, have recently been identified in patients affected by ethylmalonic encephalopathy (EE). EE is a devastating infantile metabolic disorder, characterised by widespread lesions in the brain, hyperlactic acidaemia, petechiae, orthostatic acrocyanosis, and high levels of ethylmalonic acid in body fluids. To investigate to what extent ETHE1 is responsible for EE, we analysed this gene in 29 patients with typical EE and in 11 patients presenting with early onset progressive encephalopathy with ethylmalonic aciduria (non‐EE EMA). Frameshift, stop, splice site, and missense mutations of ETHE1 were detected in all the typical EE patients analysed. Western blot analysis of the ETHE1 protein indicated that some of the missense mutations are associated with the presence of the protein, suggesting that the corresponding wild type amino acid residues have a catalytic function. No ETHE1 mutations were identified in non‐EE EMA patients. Experiments based on two dimensional blue native electrophoresis indicated that ETHE1 protein works as a supramolecular, presumably homodimeric, complex, and a three dimensional model of the protein suggests that it is likely to be a mitochondrial matrix thioesterase acting on a still unknown substrate. Finally, the 625G→A single nucleotide polymorphism in the gene encoding the short chain acyl‐coenzyme A dehydrogenase (SCAD) was previously proposed as a co‐factor in the aetiology of EE and other EMA syndromes. SNP analysis in our patients ruled out a pathogenic role of SCAD variants in EE, but did show a highly significant prevalence of the 625A alleles in non‐EE EMA patients. PMID:16183799

  13. Hepatic encephalopathy: An approach to its multiple pathophysiological features

    PubMed Central

    Perazzo, Juan Carlos; Tallis, Silvina; Delfante, Amalia; Souto, Pablo Andrés; Lemberg, Abraham; Eizayaga, Francisco Xavier; Romay, Salvador

    2012-01-01

    Hepatic encephalopathy (HE) is a neuropsychiatric complex syndrome, ranging from subtle behavioral abnormalities to deep coma and death. Hepatic encephalopathy emerges as the major complication of acute or chronic liver failure. Multiplicity of factors are involved in its pathophysiology, such as central and neuromuscular neurotransmission disorder, alterations in sleep patterns and cognition, changes in energy metabolism leading to cell injury, an oxidative/nitrosative state and a neuroinflammatory condition. Moreover, in acute HE, a condition of imminent threat of death is present due to a deleterious astrocyte swelling. In chronic HE, changes in calcium signaling, mitochondrial membrane potential and long term potential expression, N-methyl-D-aspartate-cGMP and peripheral benzodiazepine receptors alterations, and changes in the mRNA and protein expression and redistribution in the cerebral blood flow can be observed. The main molecule indicated as responsible for all these changes in HE is ammonia. There is no doubt that ammonia, a neurotoxic molecule, triggers or at least facilitates most of these changes. Ammonia plasma levels are increased two- to three-fold in patients with mild to moderate cirrhotic HE and up to ten-fold in patients with acute liver failure. Hepatic and inter-organ trafficking of ammonia and its metabolite, glutamine (GLN), lead to hyperammonemic conditions. Removal of hepatic ammonia is a differentiated work that includes the hepatocyte, through the urea cycle, converting ammonia into GLN via glutamine synthetase. Under pathological conditions, such as liver damage or liver blood by-pass, the ammonia plasma level starts to rise and the risk of HE developing is high. Knowledge of the pathophysiology of HE is rapidly expanding and identification of focally localized triggers has led the development of new possibilities for HE to be considered. This editorial will focus on issues where, to the best of our knowledge, more research is needed in

  14. [Diseases caused by mutations in mitochondrial DNA].

    PubMed

    Wojewoda, Marta; Zabłocki, Krzysztof; Szczepanowska, Joanna

    2011-01-01

    Mitochondrial diseases associated with mutations within mitochondrial genome are a subgroup of metabolic disorders since their common consequence is reduced metabolic efficiency caused by impaired oxidative phophorylation and shortage of ATP. Although the vast majority of mitochondrial proteins (approximately 1500) is encoded by nuclear genome, mtDNA encodes 11 subunits of respiratory chain complexes, 2 subunits of ATP synthase, 22 tRNAs and 2 rRNAs. Up to now, more than 250 pathogenic mutations have been described within mtDNA. The most common are point mutations in genes encoding mitochondrial tRNAs such as 3243A-->G and 8344T-->G that cause, respectively, MELAS (mitochondrial encephalopathy, lactic acidosis and stroke-like episodes) or MIDD (maternally-inherited diabetes and deafness) and MERRF (myoclonic epilepsy with ragged red fibres) syndromes. There have been also found mutations in genes encoding subunits of ATP synthase such as 8993T-->G substitution associated with NARP (neuropathy, ataxia and retinitis pigmentosa) syndrome. It is worth to note that mitochondrial dysfunction can also be caused by mutations within nuclear genes coding for mitochondrial proteins. PMID:21913424

  15. Wernicke's Encephalopathy Complicating Hyperemesis during Pregnancy.

    PubMed

    Berdai, Mohamed Adnane; Labib, Smael; Harandou, Mustapha

    2016-01-01

    Wernicke's encephalopathy is caused by severe thiamine deficiency; it is mostly observed in alcoholic patients. We report the case of a 28-year-old woman, at 17 weeks of gestational age, with severe hyperemesis gravidarum. She presented with disturbance of consciousness, nystagmus, ophthalmoplegia, and ataxia. The resonance magnetic imagery showed bilaterally symmetrical hyperintensities of thalamus and periaqueductal area. The case was managed with very large doses of thiamine. The diagnosis of Wernicke's encephalopathy was confirmed later by a low thiamine serum level. The patient was discharged home on day 46 with mild ataxia and persistent nystagmus. Wernicke's encephalopathy is a rare complication of hyperemesis gravidarum. It should be diagnosed as early as possible to prevent long-term neurological sequela or death. Thiamine supplementation in pregnant women with prolonged vomiting should be initiated, especially before parenteral dextrose infusion. Early thiamine replacement will reduce maternal morbidity and fetal loss rate. PMID:26989522

  16. Pediatric Epileptic Encephalopathies: Pathophysiology and Animal Models.

    PubMed

    Shao, Li-Rong; Stafstrom, Carl E

    2016-05-01

    Epileptic encephalopathies are syndromes in which seizures or interictal epileptiform activity contribute to or exacerbate brain function, beyond that caused by the underlying pathology. These severe epilepsies begin early in life, are associated with poor lifelong outcome, and are resistant to most treatments. Therefore, they represent an immense challenge for families and the medical care system. Furthermore, the pathogenic mechanisms underlying the epileptic encephalopathies are poorly understood, hampering attempts to devise novel treatments. This article reviews animal models of the three classic epileptic encephalopathies-West syndrome (infantile spasms), Lennox-Gastaut syndrome, and continuous spike waves during sleep or Landau-Kleffner syndrome-with discussion of how animal models are revealing underlying pathophysiological mechanisms that might be amenable to targeted therapy. PMID:27544466

  17. Why the confusion in Hashimoto's encephalopathy?

    PubMed

    Jayasekera, Bodiabaduge A P; McShane, Michael Anthony; Roy, Prem; Anand, Geetha

    2011-01-01

    A 13-year-old girl presented with an afebrile seizure followed by prolonged confusion and visual hallucinations. Initial investigations in the form of blood tests, cerebrospinal fluid analysis and head imaging by CT, were normal. She represented with two further episodes within a period of 3 weeks. Further investigations considering infective, metabolic and some autoimmune causes of encephalopathy were negative. An MRI head scan was normal. Thyroid function testing disclosed primary hypothyroidism and elevated antithyroid antibodies. She responded well to glucocorticoid therapy for presumed Hashimoto's encephalopathy (HE). HE describes patients with various neurological manifestations with elevated titres of antithyroid antibodies. There are no clear criteria for diagnosis, with many cases labelled as HE. Responses to corticosteroid therapy are favourable. In patients with unexplained encephalopathy, HE should be considered given the favourable response to glucocorticoid therapy. PMID:22691944

  18. Wernicke's Encephalopathy Complicating Hyperemesis during Pregnancy

    PubMed Central

    Berdai, Mohamed Adnane; Labib, Smael; Harandou, Mustapha

    2016-01-01

    Wernicke's encephalopathy is caused by severe thiamine deficiency; it is mostly observed in alcoholic patients. We report the case of a 28-year-old woman, at 17 weeks of gestational age, with severe hyperemesis gravidarum. She presented with disturbance of consciousness, nystagmus, ophthalmoplegia, and ataxia. The resonance magnetic imagery showed bilaterally symmetrical hyperintensities of thalamus and periaqueductal area. The case was managed with very large doses of thiamine. The diagnosis of Wernicke's encephalopathy was confirmed later by a low thiamine serum level. The patient was discharged home on day 46 with mild ataxia and persistent nystagmus. Wernicke's encephalopathy is a rare complication of hyperemesis gravidarum. It should be diagnosed as early as possible to prevent long-term neurological sequela or death. Thiamine supplementation in pregnant women with prolonged vomiting should be initiated, especially before parenteral dextrose infusion. Early thiamine replacement will reduce maternal morbidity and fetal loss rate. PMID:26989522

  19. Clinical review of genetic epileptic encephalopathies

    PubMed Central

    Noh, Grace J.; Asher, Y. Jane Tavyev; Graham, John M.

    2012-01-01

    Seizures are a frequently encountered finding in patients seen for clinical genetics evaluations. The differential diagnosis for the cause of seizures is quite diverse and complex, and more than half of all epilepsies have been attributed to a genetic cause. Given the complexity of such evaluations, we highlight the more common causes of genetic epileptic encephalopathies and emphasize the usefulness of recent technological advances. The purpose of this review is to serve as a practical guide for clinical geneticists in the evaluation and counseling of patients with genetic epileptic encephalopathies. Common syndromes will be discussed, in addition to specific seizure phenotypes, many of which are refractory to anti-epileptic agents. Divided by etiology, we overview the more common causes of infantile epileptic encephalopathies, channelopathies, syndromic, metabolic, and chromosomal entities. For each condition, we will outline the diagnostic evaluation and discuss effective treatment strategies that should be considered. PMID:22342633

  20. Hashimoto Encephalopathy or Neurosarcoidosis? A Case Report

    PubMed Central

    Sapkota, Biggya L.; Pitiyanuvath, Nataria

    2015-01-01

    Hashimoto encephalopathy (HE) is a rare autoimmune disease characterized by symptoms of acute or subacute encephalopathy associated with increased antithyroid antibody levels. Neurosarcoidosis is also a rare entity that occurs in less than 5% of patients with systemic sarcoidosis. Neurosarcoidosis usually presents with cranial neuropathies, myelopathy, or new-onset seizure. We report a case of a 49-year-old caucasian woman, previously healthy, who initially presented for a workup of a new-onset seizure. She had a gradually progressive course with neurocognitive decline and recurrent partial seizures refractory to conventional antiepileptic drugs. Her seizures responded well to a course of intravenous immunoglobulin. She was subsequently diagnosed with HE and pulmonary sarcoidosis based on serological and pathological studies. She improved neurologically once the seizures were controlled. Hashimoto encephalopathy is a rare condition that is potentially treatable and presents with various neuropsychiatric manifestations. It is a diagnosis of exclusion that requires a strong clinical suspicion and is often underrecognized. PMID:25829987

  1. Experimental Interspecies Transmission Studies of the Transmissible Spongiform Encephalopathies to Cattle: Comparison to Bovine Spongiform Encephalopathy in Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prion diseases or transmissible spongiform encephalopathies (TSEs) of animals include scrapie of sheep and goats; transmissible mink encephalopathy (TME); chronic wasting disease (CWD) of deer, elk and moose; and bovine spongiform encephalopathy (BSE) of cattle. Since the emergence of BSE and its pr...

  2. Concussion in Chronic Traumatic Encephalopathy.

    PubMed

    Stein, Thor D; Alvarez, Victor E; McKee, Ann C

    2015-10-01

    Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disease that occurs in association with repetitive mild traumatic brain injury. It is associated with a variety of clinical symptoms in multiple domains, and there is a distinct pattern of pathological changes. The abnormal tau pathology in CTE occurs uniquely in those regions of the brain that are likely most susceptible to stress concentration during trauma. CTE has been associated with a variety of types of repetitive head trauma, most frequently contact sports. In cases published to date, the mean length of exposure to repetitive head trauma was 15.4 years. The clinical symptoms of the disease began after a mean latency of 14.5 years with a mean age of death of 59.3 years. Most subjects had a reported history of concussions with a mean of 20.3. However, 16 % of published CTE subjects did not have a history of concussion suggesting that subconcussive hits are sufficient to lead to the development of CTE. Overall, the number of years of exposure, not the number of concussions, was significantly associated with worse tau pathology in CTE. This suggests that it is the chronic and repetitive nature of head trauma, irrespective of concussive symptoms, that is the most important driver of disease. CTE and exposure to repetitive head trauma is also associated with a variety of other neurodegenerations, including Alzheimer disease. In fact, amyloid β peptide deposition is altered and accelerated in CTE and is associated with worse disease. Here, we review the current exposure, clinical, and pathological associations of CTE. PMID:26260277

  3. Concussion in Chronic Traumatic Encephalopathy

    PubMed Central

    Stein, Thor D.; Alvarez, Victor E.; McKee, Ann C.

    2015-01-01

    Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disease that occurs in association with repetitive mild traumatic brain injury. It is associated with a variety of clinical symptoms in multiple domains, and there is a distinct pattern of pathological changes. The abnormal tau pathology in CTE occurs uniquely in those regions of the brain that are likely most susceptible to stress concentration during trauma. CTE has been associated with a variety of types of repetitive head trauma, most frequently contact sports. In cases published to date, the mean length of exposure to repetitive head trauma was 15.4 years. The clinical symptoms of the disease began after a mean latency of 14.5 years with a mean age of death of 59.3 years. Most subjects had a reported history of concussions with a mean of 20.3. However, 16 % of published CTE subjects did not have a history of concussion suggesting that subconcussive hits are sufficient to lead to the development of CTE. Overall, the number of years of exposure, not the number of concussions, was significantly associated with worse tau pathology in CTE. This suggests that it is the chronic and repetitive nature of head trauma, irrespective of concussive symptoms, that is the most important driver of disease. CTE and exposure to repetitive head trauma is also associated with a variety of other neurodegenerations, including Alzheimer disease. In fact, amyloid β peptide deposition is altered and accelerated in CTE and is associated with worse disease. Here, we review the current exposure, clinical, and pathological associations of CTE. PMID:26260277

  4. Minimal Hepatic Encephalopathy Impairs Quality of Life

    PubMed Central

    Agrawal, Swastik; Umapathy, Sridharan; Dhiman, Radha K.

    2015-01-01

    Minimal hepatic encephalopathy (MHE) is the mildest form of the spectrum of neurocognitive impairment in cirrhosis. It is a frequent occurrence in patients of cirrhosis and is detectable only by specialized neurocognitive testing. MHE is a clinically significant disorder which impairs daily functioning, driving performance, work capability and learning ability. It also predisposes to the development of overt hepatic encephalopathy, increased falls and increased mortality. This results in impaired quality of life for the patient as well as significant social and economic burden for health providers and care givers. Early detection and treatment of MHE with ammonia lowering therapy can reverse MHE and improve quality of life. PMID:26041957

  5. Minimal hepatic encephalopathy impairs quality of life.

    PubMed

    Agrawal, Swastik; Umapathy, Sridharan; Dhiman, Radha K

    2015-03-01

    Minimal hepatic encephalopathy (MHE) is the mildest form of the spectrum of neurocognitive impairment in cirrhosis. It is a frequent occurrence in patients of cirrhosis and is detectable only by specialized neurocognitive testing. MHE is a clinically significant disorder which impairs daily functioning, driving performance, work capability and learning ability. It also predisposes to the development of overt hepatic encephalopathy, increased falls and increased mortality. This results in impaired quality of life for the patient as well as significant social and economic burden for health providers and care givers. Early detection and treatment of MHE with ammonia lowering therapy can reverse MHE and improve quality of life. PMID:26041957

  6. Mitochondrial vasculopathy

    PubMed Central

    Finsterer, Josef; Zarrouk-Mahjoub, Sinda

    2016-01-01

    Mitochondrial disorders (MIDs) are usually multisystem disorders (mitochondrial multiorgan disorder syndrome) either on from onset or starting at a point during the disease course. Most frequently affected tissues are those with a high oxygen demand such as the central nervous system, the muscle, endocrine glands, or the myocardium. Recently, it has been shown that rarely also the arteries may be affected (mitochondrial arteriopathy). This review focuses on the type, diagnosis, and treatment of mitochondrial vasculopathy in MID patients. A literature search using appropriate search terms was carried out. Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy. Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy, migraine-like headache, stroke-like episodes, or peripheral retinopathy. Mitochondrial macroangiopathy manifests as atherosclerosis, ectasia of arteries, aneurysm formation, dissection, or spontaneous rupture of arteries. The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes. Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes. Mitochondrial vasculopathy exists and manifests as micro- or macroangiopathy. Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications. PMID:27231520

  7. Mitochondrial Cardiomyopathies

    PubMed Central

    El-Hattab, Ayman W.; Scaglia, Fernando

    2016-01-01

    Mitochondria are found in all nucleated human cells and perform various essential functions, including the generation of cellular energy. Mitochondria are under dual genome control. Only a small fraction of their proteins are encoded by mitochondrial DNA (mtDNA), whereas more than 99% of them are encoded by nuclear DNA (nDNA). Mutations in mtDNA or mitochondria-related nDNA genes result in mitochondrial dysfunction leading to insufficient energy production required to meet the needs for various organs, particularly those with high energy requirements, including the central nervous system, skeletal and cardiac muscles, kidneys, liver, and endocrine system. Because cardiac muscles are one of the high energy demanding tissues, cardiac involvement occurs in mitochondrial diseases with cardiomyopathies being one of the most frequent cardiac manifestations found in these disorders. Cardiomyopathy is estimated to occur in 20–40% of children with mitochondrial diseases. Mitochondrial cardiomyopathies can vary in severity from asymptomatic status to severe manifestations including heart failure, arrhythmias, and sudden cardiac death. Hypertrophic cardiomyopathy is the most common type; however, mitochondrial cardiomyopathies might also present as dilated, restrictive, left ventricular non-compaction, and histiocytoid cardiomyopathies. Cardiomyopathies are frequent manifestations of mitochondrial diseases associated with defects in electron transport chain complexes subunits and their assembly factors, mitochondrial transfer RNAs, ribosomal RNAs, ribosomal proteins, translation factors, mtDNA maintenance, and coenzyme Q10 synthesis. Other mitochondrial diseases with cardiomyopathies include Barth syndrome, Sengers syndrome, TMEM70-related mitochondrial complex V deficiency, and Friedreich ataxia. PMID:27504452

  8. Mitochondrial vasculopathy.

    PubMed

    Finsterer, Josef; Zarrouk-Mahjoub, Sinda

    2016-05-26

    Mitochondrial disorders (MIDs) are usually multisystem disorders (mitochondrial multiorgan disorder syndrome) either on from onset or starting at a point during the disease course. Most frequently affected tissues are those with a high oxygen demand such as the central nervous system, the muscle, endocrine glands, or the myocardium. Recently, it has been shown that rarely also the arteries may be affected (mitochondrial arteriopathy). This review focuses on the type, diagnosis, and treatment of mitochondrial vasculopathy in MID patients. A literature search using appropriate search terms was carried out. Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy. Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy, migraine-like headache, stroke-like episodes, or peripheral retinopathy. Mitochondrial macroangiopathy manifests as atherosclerosis, ectasia of arteries, aneurysm formation, dissection, or spontaneous rupture of arteries. The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes. Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes. Mitochondrial vasculopathy exists and manifests as micro- or macroangiopathy. Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications. PMID:27231520

  9. Mitochondrial Cardiomyopathies.

    PubMed

    El-Hattab, Ayman W; Scaglia, Fernando

    2016-01-01

    Mitochondria are found in all nucleated human cells and perform various essential functions, including the generation of cellular energy. Mitochondria are under dual genome control. Only a small fraction of their proteins are encoded by mitochondrial DNA (mtDNA), whereas more than 99% of them are encoded by nuclear DNA (nDNA). Mutations in mtDNA or mitochondria-related nDNA genes result in mitochondrial dysfunction leading to insufficient energy production required to meet the needs for various organs, particularly those with high energy requirements, including the central nervous system, skeletal and cardiac muscles, kidneys, liver, and endocrine system. Because cardiac muscles are one of the high energy demanding tissues, cardiac involvement occurs in mitochondrial diseases with cardiomyopathies being one of the most frequent cardiac manifestations found in these disorders. Cardiomyopathy is estimated to occur in 20-40% of children with mitochondrial diseases. Mitochondrial cardiomyopathies can vary in severity from asymptomatic status to severe manifestations including heart failure, arrhythmias, and sudden cardiac death. Hypertrophic cardiomyopathy is the most common type; however, mitochondrial cardiomyopathies might also present as dilated, restrictive, left ventricular non-compaction, and histiocytoid cardiomyopathies. Cardiomyopathies are frequent manifestations of mitochondrial diseases associated with defects in electron transport chain complexes subunits and their assembly factors, mitochondrial transfer RNAs, ribosomal RNAs, ribosomal proteins, translation factors, mtDNA maintenance, and coenzyme Q10 synthesis. Other mitochondrial diseases with cardiomyopathies include Barth syndrome, Sengers syndrome, TMEM70-related mitochondrial complex V deficiency, and Friedreich ataxia. PMID:27504452

  10. Deoxyribonucleotide pool imbalance stimulates deletions in HeLa cell mitochondrial DNA.

    PubMed

    Song, Shiwei; Wheeler, Linda J; Mathews, Christopher K

    2003-11-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder associated with multiple mutations in mitochondrial DNA, both deletions and point mutations, and mutations in the nuclear gene for thymidine phosphorylase. Spinazzola et al. (Spinazzola, A., Marti, R., Nishino, I., Andreu, A., Naini, A., Tadesse, S., Pela, I., Zammarchi, E., Donati, M., Oliver, J., and Hirano, M. (2001) J. Biol. Chem. 277, 4128-4133) showed that MNGIE patients have elevated circulating thymidine levels and they hypothesized that this generates imbalanced mitochondrial deoxyribonucleoside triphosphate (dNTP) pools, which in turn are responsible for mitochondrial (mt) DNA mutagenesis. We tested this hypothesis by culturing HeLa cells in medium supplemented with 50 microM thymidine. After 8-month growth, mtDNA in the thymidine-treated culture, but not the control, showed multiple deletions, as detected both by Southern blotting and by long extension polymerase chain reaction. After 4-h growth in thymidine-supplemented medium, we found the mitochondrial dTTP and dGTP pools to expand significantly, the dCTP pool to drop significantly, and the dATP pool to drop slightly. In whole-cell extracts, dTTP and dGTP pools also expanded, but somewhat less than in mitochondria. The dCTP pool shrank by about 50%, and the dATP pool was essentially unchanged. These results are discussed in terms of the recent report by Nishigaki et al. (Nishigaki, Y., Marti, R., Copeland, W. C., and Hirano, M. (2003) J. Clin. Invest. 111, 1913-1921) that most mitochondrial point mutations in MNGIE patients involve T --> C transitions in sequences containing two As to the 5' side of a T residue. Our finding of dTTP and dGTP elevations and dATP depletion in mitochondrial dNTP pools are consistent with a mutagenic mechanism involving T-G mispairing followed by a next-nucleotide effect involving T insertion opposite A. PMID:13679382

  11. Neuropsychological functioning in Wernicke's encephalopathy

    PubMed Central

    Behura, Sushree Sangita; Swain, Sarada Prasanna

    2015-01-01

    Context: Wernicke's encephalopathy (WE) is caused by thiamine (Vitamin B1) deficiency and most commonly found in chronic alcoholism and malnutrition. Clinically, the key features are mental status disturbances (global confusion), oculomotor abnormalities, and gait disturbances (ataxia). Apart from these clinical features, we can find deficits in neuropsychological functioning in patients with WE, which is more prominent after the improvement in the physical conditions. Neuropsychological functioning includes both basic cognitive processes (i.e., attention-concentration) as well as higher order cognitive processes (i.e., memory, executive functioning, reasoning), which is much vital for the maintenance of quality of life of an individual. However, unfortunately, in most of the cases, neuropsychological functioning is ignored by the clinicians. Materials and Methods: In this study four case reports of WE have been presented. The patients were taken from the outdoor department of Mental Health Institute, S.C.B. Medical College, Cuttack, Odisha. Neuropsychological functioning was measured by administration of PGIBBD and Quality of Life was measured by WHO-QOL BREF Odia Version. Discussion: As described in the literature, among the three cardinal signs (global confusion, ataxia, and ocular sings), the first two were present in all cases, but nystagmus was present in only two cases. Memory dysfunction was so disabling that the persons were unable to maintain a good Quality of Life and occupational impairment was prominent. There are disturbances in recent, remote memory, immediate recall, delayed recall, and attention and concentration, ultimately creating both physical and mental disability. PGI-BBD findings also suggest the overall impairment in neuropsychological functioning other than memory, that is, executive functioning, visual acuity, and depth perception. Findings of WHO-QOL BREF suggest the impairment of four domains of QOL in all the cases, but the severity

  12. PRIONS AND THE TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES

    EPA Science Inventory

    This book chapter is an invited, scholarly review of the mechanism(s) of TSEs for the 2nd edition of Metabolic Encephalopathies. Each chapter in the book assumes a professional knowledge of neuroscience and biochemistry, and the focus of the book is on the metabolic basis of dise...

  13. Epileptic encephalopathies: new genes and new pathways.

    PubMed

    Nieh, Sahar Esmaeeli; Sherr, Elliott H

    2014-10-01

    Epileptic encephalopathies represent a group of devastating epileptic disorders that occur early in life and are often characterized by pharmaco-resistant epilepsy, persistent severe electroencephalographic abnormalities, and cognitive dysfunction or decline. Next generation sequencing technologies have increased the speed of gene discovery tremendously. Whereas ion channel genes were long considered to be the only significant group of genes implicated in the genetic epilepsies, a growing number of non-ion-channel genes are now being identified. As a subgroup of the genetically mediated epilepsies, epileptic encephalopathies are complex and heterogeneous disorders, making diagnosis and treatment decisions difficult. Recent exome sequencing data suggest that mutations causing epileptic encephalopathies are often sporadic, typically resulting from de novo dominant mutations in a single autosomal gene, although inherited autosomal recessive and X-linked forms also exist. In this review we provide a summary of the key features of several early- and mid-childhood onset epileptic encephalopathies including Ohtahara syndrome, Dravet syndrome, Infantile spasms and Lennox Gastaut syndrome. We review the recent next generation sequencing findings that may impact treatment choices. We also describe the use of conventional and newer anti-epileptic and hormonal medications in the various syndromes based on their genetic profile. At a biological level, developments in cellular reprogramming and genome editing represent a new direction in modeling these pediatric epilepsies and could be used in the development of novel and repurposed therapies. PMID:25266964

  14. Intermediate dose 5-fluorouracil-induced encephalopathy.

    PubMed

    Kim, Yeon-A; Chung, Hyun Cheol; Choi, Hye Jin; Rha, Sun Young; Seong, Jin Sil; Jeung, Hei-Cheul

    2006-01-01

    As an acute neurotoxicity, high dose 5-fluorouracil (5-FU)-induced encephalopathy is well-known, but encephalopathy associated with lower dose is rarely reported. Here, we report a case of a male with anal cancer who was treated with 5-FU 1000 mg/m(2), continuous infusion for 5 days q4 weeks. At the second and the fourth cycles of chemotherapy, sudden confusion, cognitive dysfunction and disorientation occurred during 5-FU infusion. They were accompanied by hyperammonemia in the absence of focal neurological deficits or structural abnormalities. These symptoms completely disappeared and the serum ammonia level returned to normal after discontinuation of 5-FU and conservative care. In order to investigate a possible deficit of dihydropyrimidine dehydrogenase (DPD), we checked its mRNA level before and after treatment using real-time PCR. The patient's pre-treatment level was 80% compared with reference group, and it was elevated up to 187% of initial after 5-FU treatment, implying that that his encephalopathy may be 5-FU catabolite type rather than DPD deficiency. In conclusion, we report that encephalopathy can develop even with the dose of 5-FU lower than ever reported, and it should be considered as a differential diagnosis for proper management. PMID:16436463

  15. The transmissible spongiform encephalopathies of livestock.

    PubMed

    Greenlee, Justin J; Greenlee, M Heather West

    2015-01-01

    Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal protein-misfolding neurodegenerative diseases. TSEs have been described in several species, including bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep and goats, chronic wasting disease (CWD) in cervids, transmissible mink encephalopathy (TME) in mink, and Kuru and Creutzfeldt-Jakob disease (CJD) in humans. These diseases are associated with the accumulation of a protease-resistant, disease-associated isoform of the prion protein (called PrP(Sc)) in the central nervous system and other tissues, depending on the host species. Typically, TSEs are acquired through exposure to infectious material, but inherited and spontaneous TSEs also occur. All TSEs share pathologic features and infectious mechanisms but have distinct differences in transmission and epidemiology due to host factors and strain differences encoded within the structure of the misfolded prion protein. The possibility that BSE can be transmitted to humans as the cause of variant Creutzfeldt-Jakob disease has brought attention to this family of diseases. This review is focused on the TSEs of livestock: bovine spongiform encephalopathy in cattle and scrapie in sheep and goats. PMID:25991695

  16. [Myoclonic encephalopathy associated with proton pump inhibitors].

    PubMed

    Boulliat, J; Polard, E; Colin, F; Bentué-Ferrer, D; Allain, H

    2004-03-01

    Two men (66 and 73 Years) with a cardiovascular history were hospitalized for rapid onset encephalopathy associated with myoclonia and an extrapyramidal syndrome. On the basis of the French Pharmacovigilance system, this symptomatology has been attributed to the coadministration of a proton pump inhibitor, lansoprazole (15mg/day) with levodopa. Lansoprazole withdrawal led to a normalisation of the situation. PMID:15037850

  17. Extraocular mitochondrial myopathies and their differential diagnoses.

    PubMed

    Schoser, Benedikt G H; Pongratz, Dieter

    2006-06-01

    The diagnosis of mitochondrial myopathy depends upon a constellation of findings, family history, type of muscle involvement, specific laboratory abnormalities, and the results of histological, pathobiochemical and genetic analysis. In the present paper, the authors describe the diagnostic approach to mitochondrial myopathies manifesting as extraocular muscle disease. The most common ocular manifestation of mitochondrial myopathy is progressive external ophthalmoplegia (PEO). To exclude myasthenia gravis, ocular myositis, thyroid associated orbitopathy, oculopharyngeal muscular dystrophy, and congenital fibrosis of the extraocular muscles in patients with an early onset or long-lasting very slowly progressive ptosis and external ophthalmoplegia, almost without any diplopia, and normal to mildly elevated serum creatine kinase and lactate, electromyography, nerve conduction studies and MRI of the orbits should be performed. A PEO phenotype forces one to look comprehensively for other multisystemic mitochondrial features (e.g., exercise induced weakness, encephalopathy, polyneuropathy, diabetes, heart disease). Thereafter, and presently even in familiar PEO, a diagnostic muscle biopsy should be taken. Histological and ultrastructural hallmarks are mitochondrial proliferations and structural abnormalities, lipid storage, ragged-red fibers, or cytochrome-C negative myofibers. In addition, Southern blotting may reveal the common deletion, or molecular analysis may verify specific mutations of distinct mitochondrial or nuclear genes. PMID:16760117

  18. Site-specific somatic mitochondrial DNA point mutations in patients with thymidine phosphorylase deficiency

    PubMed Central

    Nishigaki, Yutaka; Martí, Ramon; Copeland, William C.; Hirano, Michio

    2003-01-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder caused by loss-of-function mutations in the gene encoding thymidine phosphorylase (TP). This deficiency of TP leads to increased circulating levels of thymidine (deoxythymidine, dThd) and deoxyuridine (dUrd) and has been associated with multiple deletions and depletion of mitochondrial DNA (mtDNA). Here we describe 36 point mutations in mtDNA of tissues and cultured cells from MNGIE patients. Thirty-one mtDNA point mutations (86%) were T-to-C transitions, and of these, 25 were preceded by 5′-AA sequences. In addition, we identified a single base-pair mtDNA deletion and a TT-to-AA mutation. Next-nucleotide effects and dislocation mutagenesis may contribute to the formation of these mutations. These results provide the first demonstration that alterations of nucleoside metabolism can induce multiple sequence-specific point mutations in humans. We hypothesize that, in patients with TP deficiency, increased levels of dThd and dUrd cause mitochondrial nucleotide pool imbalances, which, in turn, lead to mtDNA abnormalities including site-specific point mutations. PMID:12813027

  19. Site-specific somatic mitochondrial DNA point mutations in patients with thymidine phosphorylase deficiency.

    PubMed

    Nishigaki, Yutaka; Martí, Ramon; Copeland, William C; Hirano, Michio

    2003-06-01

    Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive disorder caused by loss-of-function mutations in the gene encoding thymidine phosphorylase (TP). This deficiency of TP leads to increased circulating levels of thymidine (deoxythymidine, dThd) and deoxyuridine (dUrd) and has been associated with multiple deletions and depletion of mitochondrial DNA (mtDNA). Here we describe 36 point mutations in mtDNA of tissues and cultured cells from MNGIE patients. Thirty-one mtDNA point mutations (86%) were T-to-C transitions, and of these, 25 were preceded by 5'-AA sequences. In addition, we identified a single base-pair mtDNA deletion and a TT-to-AA mutation. Next-nucleotide effects and dislocation mutagenesis may contribute to the formation of these mutations. These results provide the first demonstration that alterations of nucleoside metabolism can induce multiple sequence-specific point mutations in humans. We hypothesize that, in patients with TP deficiency, increased levels of dThd and dUrd cause mitochondrial nucleotide pool imbalances, which, in turn, lead to mtDNA abnormalities including site-specific point mutations. PMID:12813027

  20. Food Safety: Bovine Spongiform Encephalopathy (Mad Cow Disease).

    PubMed

    Acheson, David W. K.

    2002-01-01

    Bovine spongiform encephalopathy is just one of a group of diseases known as transmissible spongiform encephalopathies. Only recently has it become recognized that transmissible spongiform encephalopathies are likely due to proteins known as prions. Although it has been recognized that transmissible spongiform encephalopathies may readily spread within species, the recent observations that bovine spongiform encephalopathy in cattle may have originated from another transmissible spongiform encephalopathy in sheep, known as scrapie, is cause for concern. Further, bovine spongiform encephalopathy has now been strongly linked with a universally fatal human neurologic disease known as new variant Creutzfeldt-Jakob disease. Currently the only approach to preventing bovine spongiform encephalopathy, and subsequent new variant Creutzfeldt-Jakob disease in humans, from ingestion of bovine spongiform encephalopathy-infected material is to avoid consumption of contaminated food. Little can be done to treat food that will destroy prions and leave a palatable product. At this stage we are continuing to learn about transmissible spongiform encephalopathies and their implications on human health. This is an ever-changing situation and has an unpredictable element in terms of the extent of the current outbreaks in England and other parts of Europe. PMID:11984426

  1. Mitochondrial Diseases

    PubMed Central

    Lee, Young-Mock

    2012-01-01

    Mitochondria contain the respiratory chain enzyme complexes that carry out oxidative phosphorylation and produce the main part of cellular energy in the form of ATP. Although several proteins related with signalling, assembling, transporting, and enzymatic function can be impaired in mitochondrial diseases, most frequently the activity of the respiratory chain protein complexes is primarily or secondarily affected, leading to impaired oxygen utilization and reduced energy production. Mitochondrial diseases usually show a chronic, slowly progressive course and present with multiorgan involvement with varying onset between birth and late adulthood. Neuromuscular system is frequently affected in mitochondrial diseases. Although there is actually no specific therapy and cure for mitochondrial diseases, the understanding of the pathophysiology may further facilitate the diagnostic approach and open perspectives to future in mitochondrial diseases. PMID:24649452

  2. Microangiopathy in the cerebellum of patients with mitochondrial DNA disease

    PubMed Central

    Lax, Nichola Z.; Pienaar, Ilse S.; Reeve, Amy K.; Hepplewhite, Philippa D.; Jaros, Evelyn; Taylor, Robert W.; Kalaria, Raj N.

    2012-01-01

    Neuropathological findings in mitochondrial DNA disease vary and are often dependent on the type of mitochondrial DNA defect. Many reports document neuronal cell loss, demyelination, gliosis and necrotic lesions in post-mortem material. However, previous studies highlight vascular abnormalities in patients harbouring mitochondrial DNA defects, particularly in those with the m.3243A>G mutation in whom stroke-like events are part of the mitochondrial encephalopathy lactic acidosis and stroke-like episodes syndrome. We investigated microangiopathic changes in the cerebellum of 16 genetically and clinically well-defined patients. Respiratory chain deficiency, high levels of mutated mitochondrial DNA and increased mitochondrial mass were present within the smooth muscle cells and endothelial cells comprising the vessel wall in patients. These changes were not limited to those harbouring the m.3243A>G mutation frequently associated with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes, but were documented in patients harbouring m.8344A>G and autosomal recessive polymerase (DNA directed), gamma (POLG) mutations. In 8 of the 16 patients, multiple ischaemic-like lesions occurred in the cerebellar cortex suggestive of vascular smooth muscle cell dysfunction. Indeed, changes in vascular smooth muscle and endothelium distribution and cell size are indicative of vascular cell loss. We found evidence of blood–brain barrier breakdown characterized by plasma protein extravasation following fibrinogen and IgG immunohistochemistry. Reduced immunofluorescence was also observed using markers for endothelial tight junctions providing further evidence in support of blood–brain barrier breakdown. Understanding the structural and functional changes occurring in central nervous system microvessels in patients harbouring mitochondrial DNA defects will provide an important insight into mechanisms of neurodegeneration in mitochondrial DNA disease. Since therapeutic

  3. CoQ10 deficiencies and MNGIE: Two Treatable Mitochondrial Disorders

    PubMed Central

    Hirano, Michio; Garone, Caterine; Quinzii, Catarina M.

    2012-01-01

    Background Although causative mutations have been identified for numerous mitochondrial disorders, few disease-modifying treatments are available. Two examples of treatable mitochondrial disorders are coenzyme Q10 (CoQ10 or ubiquinone) deficiency and mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). Scope of Review Here, we describe clinical and molecular features of CoQ10 deficiencies and MNGIE and explain how understanding their pathomechanisms have led to rationale therapies. Primary CoQ10 deficiencies, due to mutations in genes required for ubiquinone biosynthesis, and secondary deficiencies, caused by genetic defects not directly related to CoQ10 biosynthesis, often improve with CoQ10 supplementation. In vitro and in vivo studies of CoQ10 deficiencies have revealed biochemical alterations that may account for phenotypic differences among patients and variable responses to therapy. In contrast to the heterogeneous CoQ10 deficiencies, MNGIE is a single autosomal recessive disease due to mutations in the TYMP gene encoding thymidine phosphorylase (TP). In MNGIE, loss of TP activity causes toxic accumulations of the nucleosides thymidine and deoxyuridine that are incorporated by the mitochondrial pyrimidine salvage pathway and cause deoxynucleoside triphosphate pool imbalances, which, in turn cause mtDNA instability. Allogeneic hematopoetic stem cell transplantation to restore TP activity and eliminate toxic metabolites is a promising therapy for MNGIE. Conclusions CoQ10 deficiencies and MNGIE demonstrate the feasibility of treating specific mitochondrial disorders through replacement of deficient metabolites or via elimination of excessive toxic molecules. General Significance Studies of CoQ10 deficiencies and MNGIE illustrate how understanding the pathogenic mechanisms of mitochondrial diseases can lead to meaningful therapies. PMID:22274133

  4. Mitochondrial cytopathies.

    PubMed

    El-Hattab, Ayman W; Scaglia, Fernando

    2016-09-01

    Mitochondria are found in all nucleated human cells and perform a variety of essential functions, including the generation of cellular energy. Most of mitochondrial proteins are encoded by the nuclear DNA (nDNA) whereas a very small fraction is encoded by the mitochondrial DNA (mtDNA). Mutations in mtDNA or mitochondria-related nDNA genes can result in mitochondrial dysfunction which leads to a wide range of cellular perturbations including aberrant calcium homeostasis, excessive reactive oxygen species production, dysregulated apoptosis, and insufficient energy generation to meet the needs of various organs, particularly those with high energy demand. Impaired mitochondrial function in various tissues and organs results in the multi-organ manifestations of mitochondrial diseases including epilepsy, intellectual disability, skeletal and cardiac myopathies, hepatopathies, endocrinopathies, and nephropathies. Defects in nDNA genes can be inherited in an autosomal or X-linked manners, whereas, mtDNA is maternally inherited. Mitochondrial diseases can result from mutations of nDNA genes encoding subunits of the electron transport chain complexes or their assembly factors, proteins associated with the mitochondrial import or networking, mitochondrial translation factors, or proteins involved in mtDNA maintenance. MtDNA defects can be either point mutations or rearrangements. The diagnosis of mitochondrial disorders can be challenging in many cases and is based on clinical recognition, biochemical screening, histopathological studies, functional studies, and molecular genetic testing. Currently, there are no satisfactory therapies available for mitochondrial disorders that significantly alter the course of the disease. Therapeutic options include symptomatic treatment, cofactor supplementation, and exercise. PMID:26996063

  5. Inherited mitochondrial disorders.

    PubMed

    Finsterer, Josef

    2012-01-01

    Though inherited mitochondrial disorders (MIDs) are most well known for their syndromic forms, for which widely known acronyms (MELAS, MERRF, NARP, LHON etc.) have been coined, the vast majority of inherited MIDs presents in a non-syndromic form. Since MIDs are most frequently multisystem disorders already at onset or during the disease course, a MID should be suspected if there is a combination of neurological and non-neurological abnormalities. Neurological abnormalities occurring as a part of a MID include stroke-like episodes, epilepsy, migraine-like headache, movement disorders, cerebellar ataxia, visual impairment, encephalopathy, cognitive impairment, dementia, psychosis, hypopituitarism, aneurysms, or peripheral nervous system disease, such as myopathy, neuropathy, or neuronopathy. Non-neurological manifestations concern the ears, the endocrine organs, the heart, the gastrointestinal tract, the kidneys, the bone marrow, and the skin. Whenever there is an unexplained combination of neurological and non-neurological disease in a patient or kindred, a MID should be suspected and appropriate diagnostic measures initiated. Genetic testing should be guided by the phenotype, the biopsy findings, and the biochemical results. PMID:22399423

  6. Severe encephalopathy associated to pyruvate dehydrogenase mutations and unbalanced coenzyme Q10 content.

    PubMed

    Asencio, Claudio; Rodríguez-Hernandez, María A; Briones, Paz; Montoya, Julio; Cortés, Ana; Emperador, Sonia; Gavilán, Angela; Ruiz-Pesini, Eduardo; Yubero, Dèlia; Montero, Raquel; Pineda, Mercedes; O'Callaghan, María M; Alcázar-Fabra, María; Salviati, Leonardo; Artuch, Rafael; Navas, Plácido

    2016-03-01

    Coenzyme Q10 (CoQ10) deficiency is associated to a variety of clinical phenotypes including neuromuscular and nephrotic disorders. We report two unrelated boys presenting encephalopathy, ataxia, and lactic acidosis, who died with necrotic lesions in different areas of brain. Levels of CoQ10 and complex II+III activity were increased in both skeletal muscle and fibroblasts, but it was a consequence of higher mitochondria mass measured as citrate synthase. In fibroblasts, oxygen consumption was also increased, whereas steady state ATP levels were decreased. Antioxidant enzymes such as NQO1 and MnSOD and mitochondrial marker VDAC were overexpressed. Mitochondria recycling markers Fis1 and mitofusin, and mtDNA regulatory Tfam were reduced. Exome sequencing showed mutations in PDHA1 in the first patient and in PDHB in the second. These genes encode subunits of pyruvate dehydrogenase complex (PDH) that could explain the compensatory increase of CoQ10 and a defect of mitochondrial homeostasis. These two cases describe, for the first time, a mitochondrial disease caused by PDH defects associated with unbalanced of both CoQ10 content and mitochondria homeostasis, which severely affects the brain. Both CoQ10 and mitochondria homeostasis appears as new markers for PDH associated mitochondrial disorders. PMID:26014431

  7. Encephalopathy of infection and systemic inflammation.

    PubMed

    Young, G Bryan

    2013-10-01

    This review will discuss several intracranial infections and sepsis-associated encephalopathy. Intracranial infections and inflammation of interest to the neurologist and EEG technicians include viral and autoimmune encephalitides; bacterial, fungal, and other meningitides; cerebritis; and brain abscess and subdural empyema. Sepsis-associated encephalopathy refers to a diffuse brain dysfunction secondary to infection that is principally located outside of the central nervous system. It is much more common than all of the intracranial infections put together, at least for adults in Western society. It probably involves a number of mechanisms that are not mutually exclusive and likely vary from patient to patient. Morbidity and mortality are directly related to the severity of SAE. The earliest features of SAE are delirium and mild EEG slowing; it is crucial to recognize these early features and to search for and treat the underlying infection promptly to reduce mortality and morbidity. PMID:24084178

  8. Hashimoto's encephalopathy: A rare proteiform disorder.

    PubMed

    Montagna, Giacomo; Imperiali, Mauro; Agazzi, Pamela; D'Aurizio, Federica; Tozzoli, Renato; Feldt-Rasmussen, Ulla; Giovanella, Luca

    2016-05-01

    Hashimoto's encephalopathy (HE) is a rare not well understood, progressive and relapsing multiform disease, characterized by seizures, movement disorders, subacute cognitive dysfunction, psychiatric symptoms and responsiveness to steroid therapy. The disorder is generally associated with thyroid diseases and the most common feature is the presence of anti-thyroperoxidase antibodies (TPOAb). Patients are usually euthyroid or mildly hypothyroid at presentation. All age groups can be affected. The pathophysiology is still unclear, especially the link between elevated serum TPOAb and the encephalopathy. Most reported cases occurred in women and girls. Unspecific symptoms, non-pathognomonic laboratory neurophysiology and neuroimaging features make its diagnosis a real challenge for clinicians. The case of a 16 year old boy, with a clinical picture of HE associated with hypothyroidism, demonstrating an excellent response to high dose steroids is presented together with a systematic review of the literature. PMID:26849953

  9. Disaccharides in the treatment of hepatic encephalopathy.

    PubMed

    Sharma, Praveen; Sharma, Barjesh Chander

    2013-06-01

    Management of hepatic encephalopathy (HE) primarily involves avoidance of precipitating factors and administration of various ammonia-lowering therapies such as nonabsorbable disaccharides and antimicrobial agents like rifaximin. The nonabsorbable disaccharides which include lactulose and lactitol are considered the first-line therapy for the treatment of HE and minimal hepatic encephalopathy (MHE). Lactulose significantly improves cognitive function and health-related quality of life in patients with MHE. Lactitol is comparable to lactulose in the treatment of HE with fewer side effects. Lactulose has also shown to be effective in primary and secondary prophylaxis of HE. Disaccharides were found to be comparable to rifaximin in recent systemic reviews in the treatment of HE however conclusion was based on inclusion of some poor quality trials. Combination therapy of disaccharides either with rifaximin, L-ornithine L-aspartate,probiotics for the treatment of HE needs further validation in large studies. PMID:23456517

  10. Head stereotypies in STXBP1 encephalopathy.

    PubMed

    Kim, Young Ok; Korff, Christian M; Villaluz, Mel Michel G; Suls, Arvid; Weckhuysen, Sarah; De Jonghe, Peter; Scheffer, Ingrid E

    2013-08-01

    STXBP1 encephalopathy is associated with a range of movement disorders. We observed head stereotypies in three patients. These comprised a slow (<1Hz), high-amplitude, horizontal, 'figure-of-eight' pattern, beginning at age 4-6 years and resulting in neck muscle hypertrophy, in two males; a faster (2-3Hz), side-to-side, 'no' movement, starting at the age of 9 years 6 months was observed in one female. Upper limb and truncal stereotypies and vocalization occurred intermittently with the head movements. The stereotypies increased with excitement but settled with concentration and sleep. Head and upper limb stereotypies are valuable clinical clues to the diagnosis of STXBP1 encephalopathy in patients with profound impairments. PMID:23763664

  11. Hemorrhagic Encephalopathy From Acute Baking Soda Ingestion

    PubMed Central

    Hughes, Adrienne; Brown, Alisha; Valento, Matthew

    2016-01-01

    Baking soda is a readily available household product composed of sodium bicarbonate. It can be used as a home remedy to treat dyspepsia. If used in excessive amounts, baking soda has the potential to cause a variety of serious metabolic abnormalities. We believe this is the first reported case of hemorrhagic encephalopathy induced by baking soda ingestion. Healthcare providers should be aware of the dangers of baking soda misuse and the associated adverse effects. PMID:27625729

  12. [Drug therapy of patients with dyscirculatory encephalopathy].

    PubMed

    Macheret, Ie L; Khanenko, N V

    2002-01-01

    Results are submitted of treatment of discirculatory encephalopathy having developed against the background of arterial hypertension, with a combination of drugs aktovegin and captopril in 56 patients. The positive effect of the instituted monotherapy has been documented clinically, with correlation established with indices of additional methods of investigation. The secured results of treatment permit recommending actovegin and captopril for a wide use in practical medicine to treat patients in the above category. PMID:12145902

  13. Wernicke's encephalopathy induced by hyperemesis gravidarum

    PubMed Central

    Palacios-Marqués, Ana; Delgado-García, Silvia; Martín-Bayón, Tina; Martínez-Escoriza, Juan Carlos

    2012-01-01

    Wernicke's encephalopathy (WE) is a reversible neurological emergency caused by thiamine deficiency. Prolonged vomiting in pregnancy results in thiamine depletion. The early recognition of its clinical signs and symptoms is essential to establish the suspected diagnosis and can be confirmed by MRI. Prompt administration of thiamine is important for preventing the occurrence of sequelae in the mother and for improving the fetal prognostic. We report a case of WE induced by hyperemesis gravidarum with a good maternal and fetal outcome. PMID:22684836

  14. Ciprofloxacin-associated posterior reversible encephalopathy

    PubMed Central

    Al Bu Ali, Waleed Hammad

    2013-01-01

    Posterior reversible encephalopathy syndrome (PRES) is a clinico-neuroradiological syndrome characterised by numerous symptoms and of no specific aetiology. Headache, confusion, seizures, cortical visual disturbances or blindness are the key symptoms. As this syndrome is reversible and readily treated by interrupting or discontinuing the aetiology, it should sharply be acknowledged. Ciprofloxacin was associated with PRES in an adolescent male treated from chest infection. It was managed in a hospital intensive care unit and was observed until disappearance. PMID:23585504

  15. Transmissible Spongiform Encephalopathy and Meat Safety

    NASA Astrophysics Data System (ADS)

    Ward, Hester J. T.; Knight, Richard S. G.

    Prion diseases or transmissible spongiform encephalopathies (TSEs) comprise a wide-ranging group of neurodegenerative diseases found in animals and humans. They have diverse causes and geographical distributions, but have similar pathological features, transmissibility and, are ultimately, fatal. Central to all TSEs is the presence of an abnormal form of a normal host protein, namely the prion protein. Because of their potential transmissibility, these diseases have wide public health ramifications.

  16. Management of Hepatic Encephalopathy in the Hospital

    PubMed Central

    Leise, Michael D.; Poterucha, John J.; Kamath, Patrick S.; Kim, W. Ray

    2014-01-01

    Hepatic encephalopathy (HE) develops in about 50% of patients with cirrhosis and is one of the features of decompensated cirrhosis. The inpatient incidence of HE is approximately 23,000/year and management of these patients is common for internists and subspecialists. Treatment of the hospitalized patient with HE has changed in recent years. Treatment entails two phases, induction and maintenance of remission. Most cases of significant hepatic encephalopathy are precipitated by infection, gastrointestinal bleeding, medications or other culprits. All patients should be evaluated for secondary triggers of HE and treatment should be initiated with a non-absorbable disaccharide (i.e. lactulose) in most cases. Rifaximin (off-label) can be added in patients not responding to lactulose. Neomycin is a less preferable alternative to rifaximin, due to its side effect profile. Other therapies including zinc, LOLA, and branch chain amino acids can be considered for patients not responding to a disaccharide and non-absorbable antibiotic. Large portosystemic shunts may be embolized in patients with medically refractory recurrent or severe HE with otherwise well compensated cirrhosis. Molecular Adsorbent Recirculating System is now available for patients with severe hepatic encephalopathy who do not respond to medical therapy. It is critically important that patients hospitalized with significant hepatic encephalopathy continue a maintenance medication(s) at the time of dismissal to prevent further episodes. Patients with a 1st time episode of HE can be placed on lactulose and careful instruction should be provided to patient and caregiver about titration of dose to achieve 3 bowel movements per day. Patients with recurrent HE episodes despite lactulose benefit from the addition of rifaximin which decreases the frequency of recurrent HE episodes and related hospitalizations. Lastly, patients and their families should be counselled about the risk of motor vehicle accidents which

  17. Heteroplasmic mutation in the anticodon-stem of mitochondrial tRNA(Val) causing MNGIE-like gastrointestinal dysmotility and cachexia.

    PubMed

    Horváth, Rita; Bender, Andreas; Abicht, Angela; Holinski-Feder, Elke; Czermin, Birgit; Trips, Tobias; Schneiderat, Peter; Lochmüller, Hanns; Klopstock, Thomas

    2009-05-01

    While mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is typically associated with mutations in the nuclear gene encoding for thymidine phosphorylase (ECGF1, TYMP), a similar clinical phenotype was described in patients carrying mutations in the nuclear-encoded polymerase gamma (POLG1) as well as a few mitochondrial tRNA genes. Here we report a novel mutation in the mitochondrial tRNA(Val) (MTTV) gene in a girl presenting with clinical symptoms of MNGIE-like gastrointestinal dysmotility and cachexia. Clinical, histological, biochemical and single cell investigations were performed. The heteroplasmic m.1630A>G mutation was detected in the mitochondrial tRNA(Val) (MTTV) gene in the patient's muscle, blood leukocytes and myoblasts, as well as in blood DNA of the unaffected mother. We provide clinical, biochemical, histological, and molecular genetic evidence on the single cell level for the pathogenicity of this mutation. Our finding adds to the genetic heterogeneity of MNGIE-like gastrointestinal symptoms and highlights the importance of a thorough genetic workup in case of suspected mitochondrial disease. PMID:19252805

  18. Valproate-induced encephalopathy with predominant pancerebellar syndrome

    PubMed Central

    Verma, Rajesh; Kori, Prakash

    2012-01-01

    Valproate-induced hyperammonemic encephalopathy is a rare event clinically characterized by impaired sensorium, vomiting, headache, seizures and focal neurological deficits. The pathogenesis of this dreadful complication is not well understood, although hyperammonemia has been implicated in causation of encephalopathy. In this submission, we have highlighted a case of valproate-induced encephalopathy who presented mainly with bilateral cerebellar features and generalized slowing on electroencephalogram. High index of suspicion of valproate-induced hyperammonemic encephalopathy is required if diffuse ataxia is present as it is a potentially reversible clinical disorder. PMID:22345888

  19. The Role of the Neurointensive Care Nursery for Neonatal Encephalopathy.

    PubMed

    Glass, Hannah C; Rowitch, David H

    2016-09-01

    Neonatal encephalopathy due to intrapartum events is estimated at 1 to 2 per 1000 live births in high-income countries. Outcomes have improved over the past decade due to implementation of therapeutic hypothermia, the only clinically available neuroprotective strategy for hypoxic-ischemic encephalopathy. Neonatal encephalopathy is the most common condition treated within a neonatal neurocritical care unit. Neonates with encephalopathy benefit from a neurocritical care approach due to prevention of secondary brain injury through attention to basic physiology, earlier recognition and treatment of neurologic complications, consistent management using guidelines and protocols, and use of optimized teams at dedicated referral centers. PMID:27524453

  20. NMDA receptors in hyperammonemia and hepatic encephalopathy.

    PubMed

    Llansola, Marta; Rodrigo, Regina; Monfort, Pilar; Montoliu, Carmina; Kosenko, Elena; Cauli, Omar; Piedrafita, Blanca; El Mlili, Nisrin; Felipo, Vicente

    2007-12-01

    The NMDA type of glutamate receptors modulates learning and memory. Excessive activation of NMDA receptors leads to neuronal degeneration and death. Hyperammonemia and liver failure alter the function of NMDA receptors and of some associated signal transduction pathways. The alterations are different in acute and chronic hyperammonemia and liver failure. Acute intoxication with large doses of ammonia (and probably acute liver failure) leads to excessive NMDA receptors activation, which is responsible for ammonia-induced death. In contrast, chronic hyperammonemia induces adaptive responses resulting in impairment of signal transduction associated to NMDA receptors. The function of the glutamate-nitric oxide-cGMP pathway is impaired in brain in vivo in animal models of chronic liver failure or hyperammonemia and in homogenates from brains of patients died in hepatic encephalopathy. The impairment of this pathway leads to reduced cGMP and contributes to impaired cognitive function in hepatic encephalopathy. Learning ability is reduced in animal models of chronic liver failure and hyperammonemia and is restored by pharmacological manipulation of brain cGMP by administering phosphodiesterase inhibitors (zaprinast or sildenafil) or cGMP itself. NMDA receptors are therefore involved both in death induced by acute ammonia toxicity (and likely by acute liver failure) and in cognitive impairment in hepatic encephalopathy. PMID:17701332

  1. Using saccades to diagnose covert hepatic encephalopathy.

    PubMed

    Cunniffe, Nicholas; Munby, Henry; Chan, Shona; Saatci, Defne; Edison, Eric; Carpenter, R H S; Massey, Dunecan

    2015-06-01

    Covert Hepatic Encephalopathy (CHE), previously known as Minimal Hepatic Encephalopathy, is a subtle cognitive defect found in 30-70 % of cirrhosis patients. It has been linked to poor quality of life, impaired fitness to drive, and increased mortality: treatment is possible. Despite its clinical significance, diagnosis relies on psychometric tests that have proved unsuitable for use in a clinical setting. We investigated whether measurement of saccadic latency distributions might be a viable alternative. We collected data on 35 cirrhosis patients at Addenbrooke's Hospital, Cambridge, with no evidence of clinically overt encephalopathy, and 36 age-matched healthy controls. Performance on standard psychometric tests was evaluated to determine those patients with CHE as defined by the World Congress of Gastroenterology. We then compared visually-evoked saccades between those with CHE and those without, as well as reviewing blood test results and correlating saccadic latencies with biochemical parameters and prognostic scores. Cirrhosis patients have significantly longer median saccadic latencies than healthy controls. Those with CHE had significantly prolonged saccadic latencies when compared with those without CHE. Analysis of a cirrhosis patient's saccades can diagnose CHE with a sensitivity of 75 % and a specificity of 75 %. We concluded that analysis of a cirrhosis patient's saccadic latency distributions is a fast and objective measure that can be used as a diagnostic tool for CHE. This improved early diagnosis could direct avoidance of high-risk activities such as driving, and better inform treatment strategies. PMID:25586511

  2. De novo mutations in epileptic encephalopathies.

    PubMed

    Allen, Andrew S; Berkovic, Samuel F; Cossette, Patrick; Delanty, Norman; Dlugos, Dennis; Eichler, Evan E; Epstein, Michael P; Glauser, Tracy; Goldstein, David B; Han, Yujun; Heinzen, Erin L; Hitomi, Yuki; Howell, Katherine B; Johnson, Michael R; Kuzniecky, Ruben; Lowenstein, Daniel H; Lu, Yi-Fan; Madou, Maura R Z; Marson, Anthony G; Mefford, Heather C; Esmaeeli Nieh, Sahar; O'Brien, Terence J; Ottman, Ruth; Petrovski, Slavé; Poduri, Annapurna; Ruzzo, Elizabeth K; Scheffer, Ingrid E; Sherr, Elliott H; Yuskaitis, Christopher J; Abou-Khalil, Bassel; Alldredge, Brian K; Bautista, Jocelyn F; Berkovic, Samuel F; Boro, Alex; Cascino, Gregory D; Consalvo, Damian; Crumrine, Patricia; Devinsky, Orrin; Dlugos, Dennis; Epstein, Michael P; Fiol, Miguel; Fountain, Nathan B; French, Jacqueline; Friedman, Daniel; Geller, Eric B; Glauser, Tracy; Glynn, Simon; Haut, Sheryl R; Hayward, Jean; Helmers, Sandra L; Joshi, Sucheta; Kanner, Andres; Kirsch, Heidi E; Knowlton, Robert C; Kossoff, Eric H; Kuperman, Rachel; Kuzniecky, Ruben; Lowenstein, Daniel H; McGuire, Shannon M; Motika, Paul V; Novotny, Edward J; Ottman, Ruth; Paolicchi, Juliann M; Parent, Jack M; Park, Kristen; Poduri, Annapurna; Scheffer, Ingrid E; Shellhaas, Renée A; Sherr, Elliott H; Shih, Jerry J; Singh, Rani; Sirven, Joseph; Smith, Michael C; Sullivan, Joseph; Lin Thio, Liu; Venkat, Anu; Vining, Eileen P G; Von Allmen, Gretchen K; Weisenberg, Judith L; Widdess-Walsh, Peter; Winawer, Melodie R

    2013-09-12

    Epileptic encephalopathies are a devastating group of severe childhood epilepsy disorders for which the cause is often unknown. Here we report a screen for de novo mutations in patients with two classical epileptic encephalopathies: infantile spasms (n = 149) and Lennox-Gastaut syndrome (n = 115). We sequenced the exomes of 264 probands, and their parents, and confirmed 329 de novo mutations. A likelihood analysis showed a significant excess of de novo mutations in the ∼4,000 genes that are the most intolerant to functional genetic variation in the human population (P = 2.9 × 10(-3)). Among these are GABRB3, with de novo mutations in four patients, and ALG13, with the same de novo mutation in two patients; both genes show clear statistical evidence of association with epileptic encephalopathy. Given the relevant site-specific mutation rates, the probabilities of these outcomes occurring by chance are P = 4.1 × 10(-10) and P = 7.8 × 10(-12), respectively. Other genes with de novo mutations in this cohort include CACNA1A, CHD2, FLNA, GABRA1, GRIN1, GRIN2B, HNRNPU, IQSEC2, MTOR and NEDD4L. Finally, we show that the de novo mutations observed are enriched in specific gene sets including genes regulated by the fragile X protein (P < 10(-8)), as has been reported previously for autism spectrum disorders. PMID:23934111

  3. Blood Biomarkers for Evaluation of Perinatal Encephalopathy

    PubMed Central

    Graham, Ernest M.; Burd, Irina; Everett, Allen D.; Northington, Frances J.

    2016-01-01

    Recent research in identification of brain injury after trauma shows many possible blood biomarkers that may help identify the fetus and neonate with encephalopathy. Traumatic brain injury shares many common features with perinatal hypoxic-ischemic encephalopathy. Trauma has a hypoxic component, and one of the 1st physiologic consequences of moderate-severe traumatic brain injury is apnea. Trauma and hypoxia-ischemia initiate an excitotoxic cascade and free radical injury followed by the inflammatory cascade, producing injury in neurons, glial cells and white matter. Increased excitatory amino acids, lipid peroxidation products, and alteration in microRNAs and inflammatory markers are common to both traumatic brain injury and perinatal encephalopathy. The blood-brain barrier is disrupted in both leading to egress of substances normally only found in the central nervous system. Brain exosomes may represent ideal biomarker containers, as RNA and protein transported within the vesicles are protected from enzymatic degradation. Evaluation of fetal or neonatal brain derived exosomes that cross the blood-brain barrier and circulate peripherally has been referred to as the “liquid brain biopsy.” A multiplex of serum biomarkers could improve upon the current imprecise methods of identifying fetal and neonatal brain injury such as fetal heart rate abnormalities, meconium, cord gases at delivery, and Apgar scores. Quantitative biomarker measurements of perinatal brain injury and recovery could lead to operative delivery only in the presence of significant fetal risk, triage to appropriate therapy after birth and measure the effectiveness of treatment. PMID:27468268

  4. Mitochondrial Myopathies

    MedlinePlus

    ... line and are therefore called the electron transport chain, and complex V actually churns out ATP, so ... coQ10 , is a component of the electron transport chain, which uses oxygen to manufacture ATP. Some mitochondrial ...

  5. Mitochondrial Diseases

    MedlinePlus

    ... in your body tissues. If you have a metabolic disorder, something goes wrong with this process. Mitochondrial diseases are a group of metabolic disorders. Mitochondria are small structures that produce energy in ...

  6. Mitochondrial DNA.

    ERIC Educational Resources Information Center

    Wright, Russell G.; Bottino, Paul J.

    1986-01-01

    Provides background information for teachers on mitochondrial DNA, pointing out that it may have once been a free-living organism. Includes a ready-to-duplicate exercise titled "Using Microchondrial DNA to Measure Evolutionary Distance." (JN)

  7. Mitochondrial Myopathy

    MedlinePlus

    ... with ragged-red fibers, and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes. The symptoms of ... riboflavin, coenzyme Q, and carnitine (a specialized amino acid) may provide subjective improvement in fatigue and energy ...

  8. Mitochondrial genetics

    PubMed Central

    Chinnery, Patrick Francis; Hudson, Gavin

    2013-01-01

    Introduction In the last 10 years the field of mitochondrial genetics has widened, shifting the focus from rare sporadic, metabolic disease to the effects of mitochondrial DNA (mtDNA) variation in a growing spectrum of human disease. The aim of this review is to guide the reader through some key concepts regarding mitochondria before introducing both classic and emerging mitochondrial disorders. Sources of data In this article, a review of the current mitochondrial genetics literature was conducted using PubMed (http://www.ncbi.nlm.nih.gov/pubmed/). In addition, this review makes use of a growing number of publically available databases including MITOMAP, a human mitochondrial genome database (www.mitomap.org), the Human DNA polymerase Gamma Mutation Database (http://tools.niehs.nih.gov/polg/) and PhyloTree.org (www.phylotree.org), a repository of global mtDNA variation. Areas of agreement The disruption in cellular energy, resulting from defects in mtDNA or defects in the nuclear-encoded genes responsible for mitochondrial maintenance, manifests in a growing number of human diseases. Areas of controversy The exact mechanisms which govern the inheritance of mtDNA are hotly debated. Growing points Although still in the early stages, the development of in vitro genetic manipulation could see an end to the inheritance of the most severe mtDNA disease. PMID:23704099

  9. Classical MERRF phenotype associated with mitochondrial tRNA(Leu) (m.3243A>G) mutation.

    PubMed

    Brackmann, Florian; Abicht, Angela; Ahting, Uwe; Schröder, Rolf; Trollmann, Regina

    2012-05-01

    Myoclonic epilepsy with ragged red fibres (MERRF) and mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) are established phenotypes of mitochondrial encephalopathies. Nearly all patients affected by MERRF harbour a mutation in the mitochondrial tRNA(Lys) gene. We report a 13-year-old patient who presented with the classical phenotype of MERRF but was found with the typical mutation of MELAS. The patient presented with myoclonic epilepsy beginning at 10 years of age, a muscle biopsy with ragged red fibres and some COX negative fibres and progressive bilateral MRI hyperintensitivities in the basal ganglia constituting MERRF syndrome but lacked clinical characteristics of MELAS. In particular, stroke-like episodes or lactic acidosis were not present. None of the tRNA mutations described in MERRF were found. However, further analyses showed the tRNA(Leu) mutation m.3243A>G usually found in MELAS to be responsible for the condition in this patient. This report highlights the broad phenotypic variability of mitochondrial encephalopathies with juvenile onset. It shows that m.3243A>G mutations can cause classical MERRF and emphasises the significance of comprehensive genetic studies if mitochondrial disease is suspected clinically. PMID:22270878

  10. Comparison of Transmissible Mink Encephalopathy Isolates in Raccoons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Owing to its susceptibility to various transmissible spongiform encephalopathies (TSE) and relatively short incubation times, the raccoon (Procyon lotor) has been suggested as a model for TSE strain differentiation. Transmissible mink encephalopathy (TME) is a prion disease of undetermined origin in...

  11. Typical and atypical cases of bovine spongiform encephalopathy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy of cattle, first detected in 1986 in the United Kingdom and subsequently in other countries. It is the most likely cause of variant Creutzfeldt-Jakob disease (vCJD) in humans, but the origin of BSE has not been eluci...

  12. [Rifaximin for hepatic encephalopathy in children. Case report].

    PubMed

    Malla, Ivone; Torres Cerino, Verónica; Villa, Andrés; Cheang, Yu; Giacove, Gisela; Pedreira, Alejandra; Silva, Marcelo

    2011-12-01

    Rifaximin is an antibiotic recently approved for the treatment of hepatic encephalopathy in adults. In children more than 12 year-old, it has been approved for travelers' diarrhea and it is also widely used in inflammatory bowel disease. We report, to our knowledge, the first case of a pediatric patient who received rifaximin for hepatic encephalopathy with good clinical outcome. PMID:22231877

  13. Evaluation of the zoonotic potential of transmissible mink encephalopathy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Successful transmission of Transmissible Mink Encephalopathy (TME) to cattle supports the bovine hypothesis to the still controversial origin of TME outbreaks. Human and primate susceptibility to classical Bovine Spongiform Encephalopathy (c-BSE) and the transmissibility of L-type BSE to macaques as...

  14. The Spectrum of Disease in Chronic Traumatic Encephalopathy

    ERIC Educational Resources Information Center

    McKee, Ann C.; Stein, Thor D.; Nowinski, Christopher J.; Stern, Robert A.; Daneshvar, Daniel H.; Alvarez, Victor E.; Lee, Hyo-Soon; Hall, Garth; Wojtowicz, Sydney M.; Baugh, Christine M.; Riley, David O.; Kubilus, Caroline A.; Cormier, Kerry A.; Jacobs, Matthew A.; Martin, Brett R.; Abraham, Carmela R.; Ikezu, Tsuneya; Reichard, Robert Ross; Wolozin, Benjamin L.; Budson, Andrew E.; Goldstein, Lee E.; Kowall, Neil W.; Cantu, Robert C.

    2013-01-01

    Chronic traumatic encephalopathy is a progressive tauopathy that occurs as a consequence of repetitive mild traumatic brain injury. We analysed post-mortem brains obtained from a cohort of 85 subjects with histories of repetitive mild traumatic brain injury and found evidence of chronic traumatic encephalopathy in 68 subjects: all males, ranging…

  15. Histopathological and imaging modifications in chronic ethanolic encephalopathy.

    PubMed

    Folescu, Roxana; Zamfir, Carmen Lăcrămioara; Sişu, Alina Maria; Motoc, Andrei Gheorghe Marius; Ilie, Adrian Cosmin; Moise, Marius

    2014-01-01

    Chronic abuse of alcohol triggers different types of brain damage. The Wernicke-Korsakoff syndrome gets together Wernicke's encephalopathy and Korsakoff's syndrome. Another type of encephalopathy associated with chronic ethanol consumption is represented by the Marchiafava-Bignami malady or syndrome, an extremely rare neurological disorder, which is characterized by a demielinization of corpus callosum, extending as far as a necrosis. Because the frequency of ethanolic encephalopathy is increased and plays a major role in the sudden death of ethanolic patients, we have studied the chronic ethanolic encephalopathy both in deceased and in living patients, presenting different pathologies related to the chronic ethanol consumption. The present study investigated the effects of chronic ethanolic encephalopathy on the central nervous system based both on the histopathological exam of the tissular samples and the imaging investigation, such as MRI and CT. PMID:25329105

  16. A Case of Severe Ganciclovir-Induced Encephalopathy

    PubMed Central

    Sakamoto, Hikaru; Hirano, Makito; Nose, Kazuhiro; Ueno, Shuichi; Oki, Takashi; Sugimoto, Koichi; Nishioka, Tsukasa; Kusunoki, Susumu; Nakamura, Yusaku

    2013-01-01

    Background Ganciclovir, a drug against cytomegalovirus (CMV) infection, is generally well tolerated, but can cause neurotoxicity such as encephalopathy. Although ganciclovir-induced encephalopathy has been described in several reports, a literature search revealed that ganciclovir concentrations in the blood or cerebrospinal fluid were previously measured in only 3 patients with encephalopathy. Symptoms usually include confusion and disturbed consciousness, which mimic CMV encephalitis. Prompt and accurate diagnosis is thus sometimes difficult, and is derived solely from accumulated clinical information of definite cases, since ganciclovir concentrations, not routinely measured, become available after several days or a few weeks. Case Presentation Here, we summarize clinical information of all patients with definite ganciclovir-induced encephalopathy including our own patient, who had severe symptoms, with the highest reported trough concentration of ganciclovir in the blood, and underwent therapeutic dialysis with complete recovery. Conclusion Our summary of patients with definite encephalopathy could lead to prompt and accurate diagnoses. PMID:24403897

  17. The Expanding Clinical Spectrum of Genetic Pediatric Epileptic Encephalopathies.

    PubMed

    Shbarou, Rolla; Mikati, Mohamad A

    2016-05-01

    Pediatric epileptic encephalopathies represent a clinically challenging and often devastating group of disorders that affect children at different stages of infancy and childhood. With the advances in genetic testing and neuroimaging, the etiologies of these epileptic syndromes are now better defined. The various encephalopathies that are reviewed in this article include the following: early infantile epileptic encephalopathy or Ohtahara syndrome, early myoclonic encephalopathy, epilepsy of infancy with migrating focal seizures, West syndrome, severe myoclonic epilepsy in infancy (Dravet syndrome), Landau-Kleffner syndrome, Lennox-Gastaut syndrome, and epileptic encephalopathy with continuous spike-and-wave during sleep. Their clinical features, prognosis as well as underlying genetic etiologies are presented and updated. PMID:27544470

  18. Mitochondrial Evolution

    PubMed Central

    Gray, Michael W.

    2012-01-01

    Viewed through the lens of the genome it contains, the mitochondrion is of unquestioned bacterial ancestry, originating from within the bacterial phylum α-Proteobacteria (Alphaproteobacteria). Accordingly, the endosymbiont hypothesis—the idea that the mitochondrion evolved from a bacterial progenitor via symbiosis within an essentially eukaryotic host cell—has assumed the status of a theory. Yet mitochondrial genome evolution has taken radically different pathways in diverse eukaryotic lineages, and the organelle itself is increasingly viewed as a genetic and functional mosaic, with the bulk of the mitochondrial proteome having an evolutionary origin outside Alphaproteobacteria. New data continue to reshape our views regarding mitochondrial evolution, particularly raising the question of whether the mitochondrion originated after the eukaryotic cell arose, as assumed in the classical endosymbiont hypothesis, or whether this organelle had its beginning at the same time as the cell containing it. PMID:22952398

  19. Neurosteroids in hepatic encephalopathy: Novel insights and new therapeutic opportunities.

    PubMed

    Butterworth, Roger F

    2016-06-01

    Hepatic encephalopathy (HE) is a serious neuropsychiatric disorder resulting from liver failure. Symptoms of HE include mild cognitive impairment, stupor and coma. Morphological changes to neuroglia (both astrocytes and microglia) occur in HE consisting of cytotoxic brain edema (astrocyte swelling) in acute liver failure and Alzheimer type-2 astrocytosis in cirrhosis. Visual-evoked responses in animals with liver failure and HE manifest striking similarities to those in animals treated with agonists of the GABA-A receptor complex. Neurosteroids are synthesized in brain following activation of translocator protein (TSPO), a mitochondrial neuroglial cholesterol-transporter protein. TSPO sites are activated in both animal models of HE as well as in autopsied brain tissue from HE patients. Activation of TSPO sites results in increased cholesterol transport into the mitochondrion followed by stimulation of a metabolic pathway culminating in the synthesis of allopregnanolone (ALLO) and tetrahydrodeoxycorticosterone (THDOC), neurosteroids with potent positive allosteric modulatory action on the GABA-A receptor complex. Concentrations of ALLO and THDOC in brain tissue from mice with HE resulting from toxic liver injury are sufficient to induce sedation in animals of the same species and significant increases in concentrations of ALLO have been reported in autopsied brain tissue from cirrhotic patients with HE leading to the proposal that "increased GABAergic tone" in HE results from that increased brain concentrations of this neurosteroid. Agents with the potential to decrease neurosteroid synthesis and/or prevent their modulatory actions on the GABA-A receptor complex may provide novel approaches to the management and treatment of HE. Such agents include indomethacin, benzodiazepine receptor inverse agonists and a novel series of compounds known as GABA-A receptor-modulating steroid antagonists (GAMSA). PMID:26589093

  20. Post-dengue encephalopathy and Parkinsonism.

    PubMed

    Fong, Choong Yi; Hlaing, Chaw Su; Tay, Chee Geap; Ong, Lai Choo

    2014-10-01

    Parkinsonism as a neurologic manifestation of dengue infection is rare with only 1 reported case in an adult patient. We report a case of a 6-year-old child with self-limiting post-dengue encephalopathy and Parkinsonism. This is the first reported pediatric case of post-dengue Parkinsonism and expands the neurologic manifestations associated with dengue infection in children. Clinicians should consider the possibility of post-dengue Parkinsonism in children with a history of pyrexia from endemic areas of dengue. PMID:24776518

  1. Hepatic Encephalopathy and Sleepiness: An Interesting Connection?

    PubMed Central

    Montagnese, Sara; Turco, Matteo; Amodio, Piero

    2015-01-01

    Sleep-wake abnormalities in patients with cirrhosis have been traditionally associated with hepatic encephalopathy (HE). In recent years, a certain amount of work has been devoted to the study of this relationship. This has lead to a modified picture, with weakening of the association between HE and poor night sleep, and the emergence of stronger links between HE and excessive daytime sleepiness. This brief review focuses on the evidence in favor of the interpretation of HE as a sleepiness syndrome, and on the diagnostic, therapeutic and social implications of such an interpretation. PMID:26041958

  2. Chronic Traumatic Encephalopathy and Movement Disorders: Update.

    PubMed

    Tarazi, Apameh; Tator, Charles H; Tartaglia, Maria Carmela

    2016-05-01

    Association of repetitive brain trauma with progressive neurological deterioration has been described since the 1920s. Punch drunk syndrome and dementia pugilistica (DP) were introduced first to explain symptoms in boxers, and more recently, chronic traumatic encephalopathy (CTE) has been used to describe a neurodegenerative disease in athletes and military personal with a history of multiple concussions. Although there are many similarities between DP and CTE, a number of key differences are apparent especially when comparing movement impairments. The aim of this review is to compare clinical and pathological aspects of DP and CTE with a focus on disorders of movement. PMID:27021775

  3. Fatal infantile mitochondrial encephalomyopathy, hypertrophic cardiomyopathy and optic atrophy associated with a homozygous OPA1 mutation

    PubMed Central

    Spiegel, Ronen; Saada, Ann; Flannery, Padraig J; Burté, Florence; Soiferman, Devorah; Khayat, Morad; Eisner, Verónica; Vladovski, Eugene; Taylor, Robert W; Bindoff, Laurence A; Shaag, Avraham; Mandel, Hanna; Schuler-Furman, Ora; Shalev, Stavit A; Elpeleg, Orly; Yu-Wai-Man, Patrick

    2016-01-01

    Background Infantile-onset encephalopathy and hypertrophic cardiomyopathy caused by mitochondrial oxidative phosphorylation defects are genetically heterogeneous with defects involving both the mitochondrial and nuclear genomes. Objective To identify the causative genetic defect in two sisters presenting with lethal infantile encephalopathy, hypertrophic cardiomyopathy and optic atrophy. Methods We describe a comprehensive clinical, biochemical and molecular genetic investigation of two affected siblings from a consanguineous family. Molecular genetic analysis was done by a combined approach involving genome-wide autozygosity mapping and next-generation exome sequencing. Biochemical analysis was done by enzymatic analysis and Western blot. Evidence for mitochondrial DNA (mtDNA) instability was investigated using long-range and real-time PCR assays. Mitochondrial cristae morphology was assessed with transmission electron microscopy. Results Both affected sisters presented with a similar cluster of neurodevelopmental deficits marked by failure to thrive, generalised neuromuscular weakness and optic atrophy. The disease progression was ultimately fatal with severe encephalopathy and hypertrophic cardiomyopathy. Mitochondrial respiratory chain complex activities were globally decreased in skeletal muscle biopsies. They were found to be homozygous for a novel c.1601T>G (p.Leu534Arg) mutation in the OPA1 gene, which resulted in a marked loss of steady-state levels of the native OPA1 protein. We observed severe mtDNA depletion in DNA extracted from the patients’ muscle biopsies. Mitochondrial morphology was consistent with abnormal mitochondrial membrane fusion. Conclusions We have established, for the first time, a causal link between a pathogenic homozygous OPA1 mutation and human disease. The fatal multisystemic manifestations observed further extend the complex phenotype associated with pathogenic OPA1 mutations, in particular the previously unreported association

  4. Mutations in BRAT1 cause autosomal recessive progressive encephalopathy: Report of a Spanish patient

    PubMed Central

    Fernández-Jáen, Alberto; Álvarez, Sara; So, Eui Young; Ouchi, Toru; de la Peña, Mar Jiménez; Duat, Anna; Fernández-Mayoralas, Daniel Martín; Fernández-Perrone, Ana Laura; Albert, Jacobo; Calleja-Pérez, Beatriz

    2016-01-01

    We describe a 4-year-old male child born to non-consanguineous Spanish parents with progressive encephalopathy (PE), microcephaly, and hypertonia. Whole exome sequencing revealed compound heterozygous BRAT1 mutations [c.1564G > A (p.Glu522Lys) and c.638dup (p.Val214Glyfs*189)]. Homozygous and compound heterozygous BRAT1 mutations have been described in patients with lethal neonatal rigidity and multifocal seizure syndrome (MIM# 614498). The seven previously described patients suffered from uncontrolled seizures, and all of those patients died in their first months of life. BRAT1 acts as a regulator of cellular proliferation and migration and is required for mitochondrial function. The loss of these functions may explain the cerebral atrophy observed in this case of PE. This case highlights the extraordinary potential of next generation technologies for the diagnosis of rare genetic diseases, including PE. Making a prompt diagnosis of PE is important for genetic counseling and disease management. PMID:26947546

  5. Mutations in BRAT1 cause autosomal recessive progressive encephalopathy: Report of a Spanish patient.

    PubMed

    Fernández-Jaén, Alberto; Álvarez, Sara; So, Eui Young; Ouchi, Toru; Jiménez de la Peña, Mar; Duat, Anna; Fernández-Mayoralas, Daniel Martín; Fernández-Perrone, Ana Laura; Albert, Jacobo; Calleja-Pérez, Beatriz

    2016-05-01

    We describe a 4-year-old male child born to non-consanguineous Spanish parents with progressive encephalopathy (PE), microcephaly, and hypertonia. Whole exome sequencing revealed compound heterozygous BRAT1 mutations [c.1564G > A (p.Glu522Lys) and c.638dup (p.Val214Glyfs*189)]. Homozygous and compound heterozygous BRAT1 mutations have been described in patients with lethal neonatal rigidity and multifocal seizure syndrome (MIM# 614498). The seven previously described patients suffered from uncontrolled seizures, and all of those patients died in their first months of life. BRAT1 acts as a regulator of cellular proliferation and migration and is required for mitochondrial function. The loss of these functions may explain the cerebral atrophy observed in this case of PE. This case highlights the extraordinary potential of next generation technologies for the diagnosis of rare genetic diseases, including PE. Making a prompt diagnosis of PE is important for genetic counseling and disease management. PMID:26947546

  6. The use of neuroimaging in the diagnosis of mitochondrial disease.

    PubMed

    Friedman, Seth D; Shaw, Dennis W W; Ishak, Gisele; Gropman, Andrea L; Saneto, Russell P

    2010-01-01

    Mutations in nuclear and mitochondrial DNA impacting mitochondrial function result in disease manifestations ranging from early death to abnormalities in all major organ systems and to symptoms that can be largely confined to muscle fatigue. The definitive diagnosis of a mitochondrial disorder can be difficult to establish. When the constellation of symptoms is suggestive of mitochondrial disease, neuroimaging features may be diagnostic and suggestive, can help direct further workup, and can help to further characterize the underlying brain abnormalities. Magnetic resonance imaging changes may be nonspecific, such as atrophy (both general and involving specific structures, such as cerebellum), more suggestive of particular disorders such as focal and often bilateral lesions confined to deep brain nuclei, or clearly characteristic of a given disorder such as stroke-like lesions that do not respect vascular boundaries in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episode (MELAS). White matter hyperintensities with or without associated gray matter involvement may also be observed. Across patients and discrete disease subtypes (e.g., MELAS, Leigh syndrome, etc.), patterns of these features are helpful for diagnosis. However, it is also true that marked variability in expression occurs in all mitochondrial disease subtypes, illustrative of the complexity of the disease process. The present review summarizes the role of neuroimaging in the diagnosis and characterization of patients with suspected mitochondrial disease. PMID:20818727

  7. Insertion near the mitochondrial tyrosine tRNA gene in patients with mitochondrial diseases

    SciTech Connect

    Goto, Y.; Nonaka, I.; Horai, S.

    1994-09-01

    The 3243 mutation commonly found in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) has been occasionally detected in patients with chronic progressive external opthalmoplegia (CPEO). To elucidate the molecular mechanism underlying this phenomenon, an extensive mitochondrial (mt) DNA study was performed on such a patient (3243-CPEO). The newly discovered insertion was located in the noncoding region between cytrochrome c oxidase subunit 1 and tyrosine tRNA. The insertion was not found in 58 or 22 CPEO patients with or without mtDNA large-scale deletion but in another 3243-CPEO patient. In addition, the insertion was present in 1 of 116 normal Japanese, who had no 3243 mutation, and in 3 of 68 3243-MELAS patients. These results raise the possibility that the phenotypic expression of the 3243 mutation could be modulated or arranged by additional mtDNA mutations.

  8. Experimental models of hepatic encephalopathy: ISHEN guidelines.

    PubMed

    Butterworth, Roger F; Norenberg, Michael D; Felipo, Vicente; Ferenci, Peter; Albrecht, Jan; Blei, Andres T

    2009-07-01

    Objectives of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism Commission were to identify well-characterized animal models of hepatic encephalopathy (HE) and to highlight areas of animal modelling of the disorder that are in need of development. Features essential to HE modelling were identified. The best-characterized animal models of HE in acute liver failure, the so-called Type A HE, were found to be the hepatic devascularized rat and the rat with thioacetamide-induced toxic liver injury. In case of chronic liver failure, surgical models in the rat involving end-to-side portacaval anastomosis or bile duct ligation were considered to best model minimal/mild (Type B) HE. Unfortunately, at this time, there are no satisfactory animal models of Type C HE resulting from end-stage alcoholic liver disease or viral hepatitis, the most common aetiologies encountered in patients. The commission highlighted the urgent need for such models and of improved models of HE in chronic liver failure in general as well as a need for models of post-transplant neuropsychiatric disorders. Studies of HE pathophysiology at the cellular and molecular level continue to benefit from in vitro and or ex vivo models involving brain slices or exposure of cultured cells (principally cultured astrocytes) to toxins such as ammonia, manganese and pro-inflammatory cytokines. More attention could be paid in the future to in vitro models involving the neurovascular unit, microglia and neuronal co-cultures in relation to HE pathogenesis. PMID:19638106

  9. Clinical presentation of chronic traumatic encephalopathy

    PubMed Central

    Daneshvar, Daniel H.; Baugh, Christine M.; Seichepine, Daniel R.; Montenigro, Philip H.; Riley, David O.; Fritts, Nathan G.; Stamm, Julie M.; Robbins, Clifford A.; McHale, Lisa; Simkin, Irene; Stein, Thor D.; Alvarez, Victor E.; Goldstein, Lee E.; Budson, Andrew E.; Kowall, Neil W.; Nowinski, Christopher J.; Cantu, Robert C.; McKee, Ann C.

    2013-01-01

    Objective: The goal of this study was to examine the clinical presentation of chronic traumatic encephalopathy (CTE) in neuropathologically confirmed cases. Methods: Thirty-six adult male subjects were selected from all cases of neuropathologically confirmed CTE at the Boston University Center for the Study of Traumatic Encephalopathy brain bank. Subjects were all athletes, had no comorbid neurodegenerative or motor neuron disease, and had next-of-kin informants to provide retrospective reports of the subjects' histories and clinical presentations. These interviews were conducted blind to the subjects' neuropathologic findings. Results: A triad of cognitive, behavioral, and mood impairments was common overall, with cognitive deficits reported for almost all subjects. Three subjects were asymptomatic at the time of death. Consistent with earlier case reports of boxers, 2 relatively distinct clinical presentations emerged, with one group whose initial features developed at a younger age and involved behavioral and/or mood disturbance (n = 22), and another group whose initial presentation developed at an older age and involved cognitive impairment (n = 11). Conclusions: This suggests there are 2 major clinical presentations of CTE, one a behavior/mood variant and the other a cognitive variant. PMID:23966253

  10. Management options for minimal hepatic encephalopathy.

    PubMed

    Bajaj, Jasmohan S

    2008-12-01

    Minimal hepatic encephalopathy (MHE) is a neurocognitive dysfunction that is present in the majority of patients with cirrhosis. MHE has a characteristic cognitive profile that cannot be diagnosed clinically. This cognitive dysfunction is independent of sleep dysfunction or problems with overall intelligence. MHE has a significant impact on quality of life, the ability to function in daily life and progression to overt hepatic encephalopathy. Driving ability can be impaired in MHE and this may be a significant factor behind motor vehicle accidents. A crucial aspect of the clinical care of MHE patients is their driving history, which is often ignored during routine care and can add a vital dimension to the overall disease assessment. Driving history should be an integral part of the care of patients with MHE. The preserved communication skills and lack of specific signs and insight make MHE difficult to diagnose. The predominant strategies for MHE diagnosis are psychometric or neurophysiological testing. These are usually limited by financial, normative or time constraints. Studies into inhibitory control, cognitive drug research and critical flicker frequency tests are encouraging. These tests do not require a psychologist for administration and interpretation. Lactulose and probiotics have been studied for their potential use as therapies for MHE, but these are not standard-of-care practices at this time. Therapy can improve the quality of life in MHE patients but the natural history, specific diagnostic strategies and treatment options are still being investigated. PMID:19090738

  11. [Clinical importance and diagnostic methods of minimal hepatic encephalopathy].

    PubMed

    Stawicka, Agnieszka; Zbrzeźniak, Justyna; Świderska, Aleksandra; Kilisińska, Natalia; Świderska, Magdalena; Jaroszewicz, Jerzy; Flisiak, Robert

    2016-02-01

    Minimal hepatic encephalopathy (MHE) encompasses a number of neuropsychological and neurophysiological disorders in patients suffering from liver cirrhosis, who do not display abnormalities during a medical interview or physical examination. A negative influence of MHE on the quality of life of patients suffering from liver cirrhosis was confirmed, which include retardation of ability of operating motor vehicles and disruption of multiple health-related areas, as well as functioning in the society. The data on frequency of traffic offences and accidents amongst patients diagnosed with MHE in comparison to patients diagnosed with liver cirrhosis without MHE, as well as healthy persons is alarming. Those patients are unaware of their disorder and retardation of their ability to operate vehicles, therefore it is of utmost importance to define this group. The term minimal hepatic encephalopathy (formerly "subclinical" encephalopathy) erroneously suggested the unnecessity of diagnostic and therapeutic procedures in patients with liver cirrhosis. Diagnosing MHE is an important predictive factor for occurrence of overt encephalopathy - more than 50% of patients with this diagnosis develop overt encephalopathy during a period of 30 months after. Early diagnosing MHE gives a chance to implement proper treatment which can be a prevention of overt encephalopathy. Due to continuing lack of clinical research there exist no commonly agreed-upon standards for definition, diagnostics, classification and treatment of hepatic encephalopathy. This article introduces the newest findings regarding the importance of MHE, scientific recommendations and provides detailed descriptions of the most valuable diagnostic methods. PMID:27000818

  12. Hepatic Encephalopathy-the Old and the New.

    PubMed

    Kandiah, Prem A; Kumar, Gagan

    2016-07-01

    Hepatic encephalopathy occurs ubiquitously in all causes of advanced liver failure, however, its implications on mortality diverge and vary depending upon acuity and severity of liver failure. This associated mortality has decreased in subsets of liver failure over the last 20 years. Aside from liver transplantation, this improvement is not attributable to a single intervention but likely to a combination of practical advances in critical care management. Misconceptions surrounding many facets of hepatic encephalopathy exists due to heterogeneity in presentation, pathophysiology and outcome. This review is intended to highlight the important concepts, rationales and strategies for managing hepatic encephalopathy. PMID:27339673

  13. Management of hepatic encephalopathy in the hospital.

    PubMed

    Leise, Michael D; Poterucha, John J; Kamath, Patrick S; Kim, W Ray

    2014-02-01

    Hepatic encephalopathy (HE) develops in up to 50% of patients with cirrhosis and is a feature of decompensated cirrhosis. With the goal of reviewing the evidence for treatment and prevention of overt hepatic encephalopathy, pubmed was searched using search terms hepatic encephalopathy AND treatment, limited to human studies from January 1, 2003, through December 1, 2013, and supplemented by key references. The inpatient incidence of HE is approximately 23,000 annually, and management of these patients is common for internists and subspecialists. Treatment of the hospitalized patient with HE has changed in recent years. Treatment entails 2 phases: induction and maintenance of remission. Most cases of significant HE are precipitated by infection, gastrointestinal bleeding, medications, or other culprits. All patients should be evaluated for secondary triggers of HE, and treatment should be initiated with a nonabsorbable disaccharide (ie, lactulose) in most patients. Rifaximin (off label) can be added in patients not responding to lactulose. Neomycin is a less preferred alternative to rifaximin owing to its adverse effect profile. Other therapies, including zinc, L-ornithine-L-aspartate, and branched-chain amino acids, can be considered for patients not responding to disaccharides and nonabsorbable antibiotics. Large portosystemic shunts may be embolized in patients with medically refractory recurrent or severe HE with otherwise well-compensated cirrhosis. Molecular Adsorbent Recirculating System is now available for patients with severe HE who do not respond to medical therapy. It is critically important that patients hospitalized with significant HE continue maintenance therapy at the time of dismissal to prevent further episodes. Patients with a first-time episode of HE can be administered lactulose, and careful instructions should be provided to patients and caregivers about dose titration to achieve 3 bowel movements daily. Patients with recurrent HE episodes

  14. Perceived fatigue is highly prevalent and debilitating in patients with mitochondrial disease

    PubMed Central

    Gorman, Gráinne S.; Elson, Joanna L.; Newman, Jane; Payne, Brendan; McFarland, Robert; Newton, Julia L.; Turnbull, Douglass M.

    2015-01-01

    Perceived fatigue is a prominent symptom in patients with mitochondrial disease but to date its prevalence, impact and aetiology are poorly understood. Our aim was to determine the prevalence and assess for comorbidities associated with clinically relevant fatigue in patients with mitochondrial disease. A cross-sectional postal survey of patients with mitochondrial disease was undertaken using a validated self-completion, patient-reported outcome measures (response rate: 60%; n = 132). The prevalence and perceived functional impact of experienced fatigue were assessed using the Fatigue Impact Scale. Other putative biological mechanisms were evaluated using the Hospital Anxiety Depression scale and Epworth sleepiness scale. Data were compared with those for healthy control subjects and patients with Myalgic Encephalopathy/Chronic Fatigue Syndrome matched for age and gender. Sixty-two per cent of patients with mitochondrial disease reported excessive symptomatic fatigue (Fatigue Impact Scale ≥ 40); whilst 32% reported severe, functionally limiting fatigue symptoms (Fatigue Impact Scale ≥ 80) comparable to perceived fatigue in patients with Myalgic Encephalopathy/Chronic Fatigue Syndrome. Fatigue is common and often severe in patients with mitochondrial disease irrespective of age, gender or genotype. Future evaluation of causal factors in mitochondrial disease-associated fatigue is warranted with the potential to guide future treatment modalities. PMID:26031904

  15. Brain MRI findings in Wernicke encephalopathy.

    PubMed

    Wicklund, Meredith R; Knopman, David S

    2013-08-01

    A 71-year-old woman with myelofibrosis on chemotherapy experienced an acute illness with nausea, vomiting, and diarrhea. Two weeks later, she developed an acute confusional state characterized by disorientation and fluctuating alertness with normal speech and language. Her neurologic examination demonstrated an upper motor neuron pattern of right hemiparesis. She reported double vision though ophthalmoparesis was not appreciated. Her gait was normal. While hospitalized, she developed generalized tonic-clonic seizures. Brain MRI revealed a small area of restricted diffusion of the left precentral gyrus (figure). She was diagnosed with a stroke with secondary seizures; however, as the confusional state resolved, she developed profound retrograde and anterograde amnesia. Review of the brain MRI showed high T2 signal in the medial thalamus and contrast enhancement of the mamillary bodies; a diagnosis of Wernicke-Korsakoff syndrome was entertained and she was started on thiamine replacement. The encephalopathy and hemiparesis resolved though she remains severely amnestic. PMID:24195023

  16. Pathogenesis, Diagnosis, and Treatment of Hepatic Encephalopathy

    PubMed Central

    Atluri, Dileep K; Prakash, Ravi; Mullen, Kevin D

    2011-01-01

    Hepatic encephalopathy (HE) is a neuropsychiatric disorder seen in patients with advanced liver disease or porto-systemic shunts. Based on etiology and severity of HE, the World Congress of Gastroenterology has divided HE into categories and sub-categories. Many user-friendly computer-based neuropsychiatric tests are being validated for diagnosing covert HE. Currently, emphasis is being given to view HE deficits as a continuous spectrum rather than distinct stages. Ammonia is believed to play crucial role in pathogenesis of HE via astrocyte swelling and cerebral edema. However, evidence has been building up which supports the synergistic role of oxidative stress, inflammation and neurosteroids in pathogenesis of HE. At present, treatment of HE aims at decreasing the production and intestinal absorption of ammonia. But as the role of new pathogenetic mechanisms becomes clear, many potential new treatment strategies may become available for clinician. PMID:25755319

  17. Leucine metabolism in patients with Hepatic Encephalopathy

    SciTech Connect

    McGhee, A.S.; Kassouny, M.E.; Matthews, D.E.; Millikan, W.

    1986-03-01

    A primed continuous infusion of (/sup 15/N, 1-/sup 13/C)leucine was used to determine whether increased oxidation and/or protein synthesis of leucine occurs in patients with cirrhosis. Five controls and patients were equilibrated on a metabolic balance diet (0.6 g protein per kg ideal body weight (IBW)). An additional four patients were equilibrated in the same manner with the same type of diet with a protein level of 0.75 g per kg IBW. Plasma leucine and breath CO/sub 2/ enrichments were measured by mass spectrometry. Protein synthesis and leucine metabolism were identical in controls and patients when both were fed a diet with 0.6 g protein/kg IBW. Results indicate that systemic derangements of leucine metabolism are not the cause of Hepatic Encephalopathy.

  18. Hyperammonemic Encephalopathy Caused by Carnitine Deficiency

    PubMed Central

    Zucker, Stephen D.

    2007-01-01

    Carnitine is an essential co-factor in fatty acid metabolism. Carnitine deficiency can impair fatty acid oxidation, rarely leading to hyperammonemia and encephalopathy. We present the case of a 35-year-old woman who developed acute mental status changes, asterixis, and diffuse muscle weakness. Her ammonia level was elevated at 276 μg/dL. Traditional ammonia-reducing therapies were initiated, but proved ineffective. Pharmacologic, microbial, and autoimmune causes for the hyperammonemia were excluded. The patient was severely malnourished and her carnitine level was found to be extremely low. After carnitine supplementation, ammonia levels normalized and the patient’s mental status returned to baseline. In the setting of refractory hyperammonemia, this case illustrates how careful investigation may reveal a treatable condition. PMID:18080167

  19. Wernicke's encephalopathy: expanding the diagnostic toolbox.

    PubMed

    Lough, Mary E

    2012-06-01

    Wernicke's encephalopathy (WE) is a life threatening neurological disorder that results from thiamine (Vitamin B1) deficiency. Clinical signs include mental status changes, ataxia, occulomotor changes and nutritional deficiency. The conundrum is that the clinical presentation is highly variable. WE clinical signs, brain imaging, and thiamine blood levels, are reviewed in 53 published case reports from 2001 to 2011; 81 % (43/53) were non-alcohol related. Korsakoff Syndrome or long-term cognitive neurological changes occurred in 28 % (15/53). Seven WE cases (13 %) had a normal magnetic resonance image (MRI). Four WE cases (8 %) had normal or high thiamine blood levels. Neither diagnostic tool can be relied upon exclusively to confirm a diagnosis of WE. PMID:22577001

  20. Does this patient have hypertensive encephalopathy?

    PubMed

    Christopoulou, Foteini; Rizos, Evangelos C; Kosta, Paraskevi; Argyropoulou, Maria I; Elisaf, Moses

    2016-05-01

    A 63-year-old man was admitted to our hospital for further investigation and management of brain metastases. The patient was initially presented with a 4-day history of confusion. On the day of admission, the patient was confused, agitated, disorientated in place and time, and had visual disturbances. His blood pressure was repeatedly recorded high, with levels of systolic blood pressure between 170-210 mm Hg. A brain magnetic resonance imaging showed areas of high signal on T2 and fluid-attenuated inversion recovery images, located bilaterally in the white matter of the occipital regions and unilateral in the left frontal lobe, suggestive of posterior reversible encephalopathy syndrome. Aggressive treatment of hypertension resulted in complete resolution of the clinical and radiologic features of the syndrome. PMID:26896240

  1. Hypoxic Ischemic Encephalopathy: Pathophysiology and Experimental Treatments

    PubMed Central

    Allen, Kimberly A.; Brandon, Debra H.

    2011-01-01

    Hypoxic ischemic encephalopathy (HIE) is a serious birth complication affecting full term infants: 40–60% of affected infants die by 2 years of age or have severe disabilities. The majority of the underlying pathologic events of HIE are a result of impaired cerebral blood flow and oxygen delivery to the brain with resulting primary and secondary energy failure. In the past, treatment options were limited to supportive medical therapy. Currently, several experimental treatments are being explored in neonates and animal models to ameliorate the effects of secondary energy failure. This review discusses the underlying pathophysiologic effects of a hypoxic-ischemic event and experimental treatment modalities being explored to manage infants with HIE. Further research is needed to better understand if the long-term impact of the experimental treatments and whether the combinations of experimental treatments can improve outcomes in infants with HIE. PMID:21927583

  2. Chronic Traumatic Encephalopathy: The Impact on Athletes.

    PubMed

    Galgano, Michael A; Cantu, Robert; Chin, Lawrence S

    2016-01-01

    Chronic traumatic encephalopathy (CTE) is a devastating neuropsychological condition afflicting a small percentage of athletes partaking in high-impact sports. The onset of symptoms lags years behind the inciting events. Repetitive minor head injuries are felt to be the main etiology behind CTE. Routine radiographic imaging generally is unremarkable in cases of CTE. Functional magnetic resonance imaging (fMRI), magnetic resonance spectroscopy (MRS), and diffusion tensor imaging (DTI) are advanced MRI-based sequences that have shown promise in detecting early radiographic findings that may be reflective of CTE. Progressive neuronal loss is the histopathological hallmark of this neurodegenerative disease. Strategizing earlier detection techniques is paramount in delivering optimal care to athletes afflicted with CTE. PMID:27088064

  3. Optic nerve hypoplasia, encephalopathy, and neurodevelopmental handicap.

    PubMed Central

    Burke, J P; O'Keefe, M; Bowell, R

    1991-01-01

    Abnormalities of the central nervous system are frequently described in optic nerve hypoplasia. In a longitudinal study of 46 consecutive children (32 term, 14 preterm) with bilateral optic nerve hypoplasia 32 (69.5%) had associated neurodevelopmental handicap. Of these, 90% had structural central nervous system abnormalities on computed tomographic brain scans. Neurodevelopmental handicap occurred in 62.5% of the term and 86% of the preterm infants respectively. Term infants had a greater incidence of ventral developmental midline defects and proportionately fewer maternal and/or neonatal complications throughout pregnancy, while encephaloclastic lesions were commoner among the premature infants. An association of optic nerve hypoplasia with the twin transfusion syndrome and prenatal vascular encephalopathies is described. PMID:2021594

  4. Hepatic Encephalopathy: Pharmacological Therapies Targeting Ammonia.

    PubMed

    Rahimi, Robert S; Rockey, Don C

    2016-02-01

    Hepatic encephalopathy (HE) is a major complication in patients with decompensated cirrhosis, leading to higher readmission rates causing a profound burden of disease and considerable health care costs. Because ammonia is thought to play a crucial role in the pathogenesis of HE, therapies directed at reducing ammonia levels are now being aggressively developed. Ammonia scavengers such as AST-120 (spherical carbon adsorbent), glycerol phenylbutyrate, sodium phenylacetate or sodium benzoate, and ornithine phenylacetate have been used to improve HE symptoms. A new approach, bowel cleansing with polyethylene glycol 3350, appears to be a promising therapy, with a recent study demonstrating a more rapid improvement in overt HE (at 24 hours after treatment) than lactulose. Extracorporeal devices, although now used primarily in research settings, have also been utilized in patients with refractory HE, but are not approved for clinical management. PMID:26870932

  5. Is chronic traumatic encephalopathy a real disease?

    PubMed

    Randolph, Christopher

    2014-01-01

    Chronic traumatic encephalopathy (CTE) has received widespread media attention and is treated in the lay press as an established disease, characterized by suicidality and progressive dementia. The extant literature on CTE is reviewed here. There currently are no controlled epidemiological data to suggest that retired athletes are at increased risk for dementia or that they exhibit any type of unique neuropathology. There remain no established clinical or pathological criteria for diagnosing CTE. Despite claims that CTE occurs frequently in retired National Football League (NFL) players, recent studies of NFL retirees report that they have an all-cause mortality rate that is approximately half of the expected rate, and even lower suicide rates. In addition, recent clinical studies of samples of cognitively impaired NFL retirees have failed to identify any unique clinical syndrome. Until further controlled studies are completed, it appears to be premature to consider CTE a verifiable disease. PMID:24412888

  6. Neuroprotective Strategies after Neonatal Hypoxic Ischemic Encephalopathy

    PubMed Central

    Dixon, Brandon J.; Reis, Cesar; Ho, Wing Mann; Tang, Jiping; Zhang, John H.

    2015-01-01

    Neonatal hypoxic ischemic encephalopathy (HIE) is a devastating disease that primarily causes neuronal and white matter injury and is among the leading cause of death among infants. Currently there are no well-established treatments; thus, it is important to understand the pathophysiology of the disease and elucidate complications that are creating a gap between basic science and clinical translation. In the development of neuroprotective strategies and translation of experimental results in HIE, there are many limitations and challenges to master based on an appropriate study design, drug delivery properties, dosage, and use in neonates. We will identify understudied targets after HIE, as well as neuroprotective molecules that bring hope to future treatments such as melatonin, topiramate, xenon, interferon-beta, stem cell transplantation. This review will also discuss some of the most recent trials being conducted in the clinical setting and evaluate what directions are needed in the future. PMID:26389893

  7. Neuroprotective Strategies after Neonatal Hypoxic Ischemic Encephalopathy.

    PubMed

    Dixon, Brandon J; Reis, Cesar; Ho, Wing Mann; Tang, Jiping; Zhang, John H

    2015-01-01

    Neonatal hypoxic ischemic encephalopathy (HIE) is a devastating disease that primarily causes neuronal and white matter injury and is among the leading cause of death among infants. Currently there are no well-established treatments; thus, it is important to understand the pathophysiology of the disease and elucidate complications that are creating a gap between basic science and clinical translation. In the development of neuroprotective strategies and translation of experimental results in HIE, there are many limitations and challenges to master based on an appropriate study design, drug delivery properties, dosage, and use in neonates. We will identify understudied targets after HIE, as well as neuroprotective molecules that bring hope to future treatments such as melatonin, topiramate, xenon, interferon-beta, stem cell transplantation. This review will also discuss some of the most recent trials being conducted in the clinical setting and evaluate what directions are needed in the future. PMID:26389893

  8. Chronic Traumatic Encephalopathy: The Impact on Athletes

    PubMed Central

    Cantu, Robert; Chin, Lawrence S.

    2016-01-01

    Chronic traumatic encephalopathy (CTE) is a devastating neuropsychological condition afflicting a small percentage of athletes partaking in high-impact sports. The onset of symptoms lags years behind the inciting events. Repetitive minor head injuries are felt to be the main etiology behind CTE. Routine radiographic imaging generally is unremarkable in cases of CTE. Functional magnetic resonance imaging (fMRI), magnetic resonance spectroscopy (MRS), and diffusion tensor imaging (DTI) are advanced MRI-based sequences that have shown promise in detecting early radiographic findings that may be reflective of CTE. Progressive neuronal loss is the histopathological hallmark of this neurodegenerative disease. Strategizing earlier detection techniques is paramount in delivering optimal care to athletes afflicted with CTE. PMID:27088064

  9. Safety, efficacy, and patient acceptability of rifaximin for hepatic encephalopathy.

    PubMed

    Kimer, Nina; Krag, Aleksander; Gluud, Lise L

    2014-01-01

    Hepatic encephalopathy is a complex disease entity ranging from mild cognitive dysfunction to deep coma. Traditionally, treatment has focused on a reduction of ammonia through a reduced production, absorption, or clearance. Rifaximin is a nonabsorbable antibiotic, which reduces the production of ammonia by gut bacteria and, to some extent, other toxic derivatives from the gut. Clinical trials show that these effects improve episodes of hepatic encephalopathy. A large randomized trial found that rifaximin prevents recurrent episodes of hepatic encephalopathy. Most patients were treated concurrently with lactulose. Trials have varied greatly in design, outcomes, and duration of treatment regimes. Although a number of retrospective studies have indicated that long-term treatment with rifaximin is safe and possibly beneficial, high quality trials are needed to further clarify efficacy and safety of long-term treatment with rifaximin and evaluate effects of combination therapy with lactulose and branched-chain amino acids for patients with liver cirrhosis and hepatic encephalopathy. PMID:24672227

  10. Safety, efficacy, and patient acceptability of rifaximin for hepatic encephalopathy

    PubMed Central

    Kimer, Nina; Krag, Aleksander; Gluud, Lise L

    2014-01-01

    Hepatic encephalopathy is a complex disease entity ranging from mild cognitive dysfunction to deep coma. Traditionally, treatment has focused on a reduction of ammonia through a reduced production, absorption, or clearance. Rifaximin is a nonabsorbable antibiotic, which reduces the production of ammonia by gut bacteria and, to some extent, other toxic derivatives from the gut. Clinical trials show that these effects improve episodes of hepatic encephalopathy. A large randomized trial found that rifaximin prevents recurrent episodes of hepatic encephalopathy. Most patients were treated concurrently with lactulose. Trials have varied greatly in design, outcomes, and duration of treatment regimes. Although a number of retrospective studies have indicated that long-term treatment with rifaximin is safe and possibly beneficial, high quality trials are needed to further clarify efficacy and safety of long-term treatment with rifaximin and evaluate effects of combination therapy with lactulose and branched-chain amino acids for patients with liver cirrhosis and hepatic encephalopathy. PMID:24672227