Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019209 (hepatomegaly)
 5,798 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three children displaying hypotonia, cardiac involvement and defects of the mitochondrial respiratory chain complexes are reported. The first case showed severe neonatal hypotonia, failure to thrive, hepatomegaly, dilation of the right cardiac cavities, profound lactic acidosis and amino aciduria. The boy died at the age of 7 weeks. In the second case hypotonia, severe cardiomyopathy, cyclic neutropenia, lactic acidosis and 3-methylglutaconic aciduria occurred. The boy died at the age of 27 months. The third case presented at the age of 16 months as an acute hypokinetic hypertrophic cardiomyopathy with transient hypotonia and mild lactic acidosis. Spontaneous clinical remission occurred. In all cases muscle biopsy was performed. Morphological studies failed to show ragged-red fibers but there was lipid storage myopathy and decreased cytochrome c oxidase activity. Biochemical studies confirmed the cytochrome c oxidase deficiency in muscle in all cases. It was associated with complex I III deficiency in case 1 and with severe deficits of all respiratory chain complexes in case 2. Post-mortem studies in case 1 indicated that complex IV was reduced in the liver but not in the heart and quantitative analysis of mtDNA revealed a depletion in muscle. Cases 1 and 2 shared some clinical features with fatal infantile myopathy associated with cytochrome c oxidase deficiency, while case 3 displayed a very unusual clinical presentation. The histochemical enzyme reaction of cytochrome c oxidase is useful for the diagnosis of mitochondrial myopathy because ragged-red fibers may be lacking. Finally, biochemical measurement of the different mitochondrial respiratory chain complexes is required because multiple defects are frequent and occasionally related to mtDNA depletion.
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PMID:Defects of the mitochondrial respiratory chain complexes in three pediatric cases with hypotonia and cardiac involvement. 132 Jun 61

A newborn female, the second child of consanguineous parents, exhibited general muscle hypotonia, apathy, hepatomegaly and failure to thrive from birth and signs of craniofacial dysmorphia were present. Pipecolic and trihydroxicoprostanoic acid were excreted in the urine and serum transferrin, ferritin and iron were markedly elevated. At the age of 7 weeks the baby died of respiratory insufficiency. Besides malformations of the brain, renal cysts, liver damage with hypoplastic intrahepatic bile ducts and cholestasis, increased storage of iron and cytochemically proven deficiency of peroxisomes in liver and kidney, morphological studied provided evidence of a mitochondrial myopathy in striated muscle with the accumulation of enlarged bizarre mitochondria, showing only minor structural abnormalities. No defects of NADH-reductase, succinate-dehydrogenase or cytochrome-c-oxidase were demonstrated histochemically. Cytochemical-ultrastructural investigation of mitochondrial ATPase revealed activation of the ATP-synthesising enzyme even before the addition of an uncoupler, this indicating loosely coupled oxidative phosphorylation. In addition a high rate of subcellular autophagy with segregation of mitochondria and focal loss of fibrils was present. Muscle damage in Zellweger syndrome appears to be the consequence of complex, interacting metabolic processes. The mitochondrial myopathy thereby induced allows a better understanding of general muscle hypotonia, one of the leading symptoms of this disorder.
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PMID:Mitochondrial myopathy with loosely coupled oxidative phosphorylation in a case of Zellweger syndrome. A cytochemical-ultrastructural study. 614 41

Fatal infantile mitochondrial myopathy with lactic acidosis, morphologically abnormal mitochondria, deficient cytochromes aa3 and b, and a Fanconi-like aminoaciduria has been described. We report two infants, second cousins, with a similar fatal mitochondrial disorder, the cytochrome deficiency limited to skeletal muscle in one child and to liver in the other. The first child at 3 months of age had weight loss, hypotonia, external ophthalmoplegia, and a severe lactic acidosis with a high lactate/pyruvate ratio. Electron microscopy of muscle showed marked proliferation of enlarged mitochondria, many containing concentric rings of cristae. In skeletal muscle mitochondria, cytochromes aa3 and b were not detectable but cytochrome cc was found to be normal by spectroscopy. Cytochrome c oxidase activity was less than 1% of normal. Mitochondria from kidney, liver, heart, lung, and brain examined postmortem had normal cytochromes and preserved cytochrome c oxidase activity. The second cousin at 5 months of age had weight loss and hepatomegaly but no systemic lactic acidosis. Liver biopsy showed hepatocytes packed with enlarged mitochondria. The liver mitochondria showed deficient cytochromes aa3 and b postmortem, and cytochrome c oxidase activity was less than 10% of normal. Kidney mitochondria had normal cytochromes. Muscles was not studied. The mitochondrial abnormality in the two cousins presumably is related. Unexplained are the mode of genetic transmission or environmental exposure and the apparent involvement of a single different organ in each child.
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PMID:Mitochondrial cytochrome deficiency presenting as a myopathy with hypotonia, external ophthalmoplegia, and lactic acidosis in an infant and as fatal hepatopathy in a second cousin. 631 75

A 2-month-old girl had generalized weakness, profound muscular hypotonia, hepatomegaly and severe lactic acidosis. She needed ventilatory support. Muscle specimen taken at 2 months showed ragged-red fibers, abnormal mitochondria, and reduced cytochrome c oxidase (CCO) staining Biochemical analysis showed CCO activity to be reduced to about 16% of the normal mean. She received carnitine and coenzyme Q10 supplementation from the age of 3 months and abnormal blood lactate values declined to near normal values during the first three weeks. Gradually her condition started to improved: she held her head at 9 months, and walked alone at 15 months. The second biopsy specimen at 3 years and 8 months showed almost normal CCO staining and she was free of clinical signs. This case is an example of a rare benign infantile mitochondrial myopathy caused by CCO deficiency. Early diagnosis is crucial to provide intensive treatment until spontaneous clinical improvement appears. We concluded that carnitine and coenzyme Q10 supplementation was a useful treatment for clinical improvement in patients with a benign infantile mitochondrial myopathy caused by CCO deficiency.
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PMID:[Benign infantile mitochondrial myopathy caused by reversible cytochrome c oxidase deficiency]. 883 Dec 49

Type B lactic acidosis, a rare but often fatal disorder, has been reported in 21 AIDS patients on antiretroviral therapy (ART). We present an AIDS patient with severe and prolonged lactic acidosis on stavudine and lamivudine. The lactic acidosis occurred in the absence of mitochondrial myopathy, hepatomegaly, or liver failure. This is the second report of lactic acidosis in a patient on stavudine and lamivudine. This patient recovered after aggressive supportive therapy including intravenous alkali and fluid administration as well as continuous venovenous hemodiafiltration. A single dose of dichloroacetate (DCA) was associated with a decrease in the serum lactate level by 20%, which persisted for more than 24 h. Seventeen months after recovery, the patient was rechallenged with ART without recurrence of lactic acidosis. We review and summarize all reported cases of patients with ART-associated lactic acidosis reported in the English literature.
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PMID:Lactic acidosis in the setting of antiretroviral therapy for the acquired immunodeficiency syndrome. A case report and review of the literature. 1097 Sep 89

Mitochondrial dysfunction is an important cause of metabolic disorders of children and adults, with no effective therapy options. Recently, induction of mitochondrial biogenesis, by transgenic overexpression of PGC1-alpha [peroxisome proliferator-activated receptor (PPAR)-gamma coactivator 1-alpha], was reported to delay progression of early-onset cytochrome-c-oxidase (COX) deficiency in skeletal muscle of two mouse models: a muscle-specific knock-out of COX10 (COX10-mKO) and a constitutive knock-out of Surf1 (Surf1-KO). A pan-PPAR agonist, bezafibrate, could similarly delay myopathy progression in COX10-mKOs, but not in SURF1-KOs. We asked whether bezafibrate affected disease progression in late-onset adult-type mitochondrial myopathy mice. These 'Deletor mice' express a dominant patient mutation in Twinkle-helicase, leading to accumulation of multiple mtDNA deletions and subsequent progressive respiratory chain (RC) deficiency with COX-negative muscle fibers at 12 months of age. The primary and secondary molecular findings in Deletor mice mimic closely those in patients with Twinkle myopathy. We applied 0.5% bezafibrate diet to Deletors for 22 weeks, starting at disease manifestation, mimicking patient treatment after diagnosis. Bezafibrate delayed significantly the accumulation of COX-negative fibers and multiple mtDNA deletions. However, mitochondrial biogenesis was not induced: mitochondrial DNA copy number, transcript and RC protein amounts decreased in both Deletors and wild-type mice. Furthermore, bezafibrate induced severe lipid oxidation effects, with hepatomegaly and loss of adipose tissue, the mechanism involving lipid mobilization by high hepatic expression of FGF21 cytokine. However, as bezafibrate has been tolerated well by humans, the beneficial muscle findings in Deletor mice support consideration of bezafibrate trials on adult patients with mitochondrial myopathy.
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PMID:Effect of bezafibrate treatment on late-onset mitochondrial myopathy in mice. 2201 83

Thirty five floppy children seen during two year period, were subjected to clinical examination, electroneuromyography and muscle biopsy. The muscle biopsy was sent for routine histology, histochemistry and electron microscopy. Using muscle pathology as the 'gold standard' for diagnosis, the aetiological entities were spinal muscular atrophy (16), congenital muscular dystrophy (6), mitochondrial myopathy (3), congenital fibre type disproportion (2), acid mutase deficiency (1) and benign congenital hypotonia (6). Mental subnormality, seizures, ptosis and ophthalmoplegia suggested mitochondrial disease (n=2). Macroglossia, hepatomegaly and cardiomegaly along with the dive bomber effect on electromyography were useful clues to the diagnosis of Pompe's disease (n=1). Positive decremental test established the diagnosis of congenital myasthenia in one patient. Contrary to most previously published reports, infantile onset of spinal muscular atrophy did not always spell a poor prognosis on follow up. 'Floppy infant syndrome' has varied etiology. Comprehensive evaluation including clinical, electrophysiological and detailed histological examination is necessary for proper diagnosis and prognosis of this heterogenous entity.
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PMID:Neuromuscular disorders in infancy and childhood. 2951 74