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)

Peroxisome-deficient disorders including Zellweger syndrome, neonatal adrenoleukodystrophy and infantile Refsum disease are characterized by hypotonia, psychomotor delay, hepatomegaly and dysmorphism. Multiple peroxisomal enzymes are deficient in these disorders probably due to the defect of transport machinery of enzymes. Defects of beta-oxidation enzymes causes an accumulation of very-long-chain fatty acids, which is closely related to the pathogenesis. Catalase, a marker enzyme of peroxisome, is distributed in the cytosol. Immunocytochemical staining of peroxisomes using anti-catalase is a useful tool for prenatal and postnatal diagnosis. Although the primary etiology of peroxisomal deficiency has not been determined, genetic heterogeneity was clarified by complementation studies. At least 8 genes are involved in the formation of functional peroxisomes.
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PMID:[Clinical biochemical and genetic aspects of peroxisome-deficient disorders]. 137 33

We describe a relatively new syndrome in four children with characteristic facial dysmorphism, sensorineural hearing loss, severe visual impairment with retinitis pigmentosa, hypotonia, hepatomegaly, and severe developmental delay. Two patients had intracranial hemorrhage secondary to a vitamin K-responsive clotting defect; both had steatorrhea. Liver biopsy specimens in two children showed an accentuated lobular architecture with prominent fibrous bands in the portal area. In one, the ultrastructure showed accumulation of abnormal substances and occasional trilaminar structures in hepatocytes and other cells. All four patients had elevated serum phytanic acid concentrations (0.3 to 2.7 mg/dl, normal less than 0.2 mg/dl) and deficient fibroblast phytanic acid oxidase activity (0.1 to 6.7 pmol/mg protein/hr, normal 23 to 87 pmol/mg protein/hr). Serum pipecolic acid was 7 to 55 times normal, and the ratio of C26/C22 very long chain fatty acids was increased (0.10 to 0.22; normal less than 0.03). This characteristic syndrome has been described in several children and called infantile Refsum disease or phytanic acid storage disease. Its relationship to neonatal adrenoleukodystrophy, hyperpipecolic acidemia, and Zellweger syndrome is discussed.
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PMID:Dysmorphic syndrome with phytanic acid oxidase deficiency, abnormal very long chain fatty acids, and pipecolic acidemia: studies in four children. 241 87

Nine cases of neonatal adrenoleukodystrophy are described. All patients had abnormal facial features, moderate to severe hypotonia, hepatomegaly, and retinitis pigmentosa. The clinical course was rapidly progressive in six cases and more protracted in three others. Biological signs of adrenal insufficiency were present in five cases. CT scan showed a demyelinating process in four patients. Trilamellar inclusions were found in the liver of four cases and dark and complex lipidic inclusions in three other cases. In the three necropsied patients there was severe alteration of the white matter involving particularly the cerebellum in two cases. Gyral and cytoarchitectonic disturbances were absent in all three cases. Increased plasma levels of very long chain fatty acids (8/8), phytanic acid (7/8) and bile fluid trihydroxycoprostanic acid (2/4) confirmed the deficiency of multiple peroxisomal enzymes. Clinical, histopathological and biochemical findings of these nine cases are compared to those reported in other neonatal adrenoleukodystrophy cases and to those of other neonatal peroxisomal disorders, that is cerebro-hepato-renal syndrome of Zellweger and infantile Refsum's disease.
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PMID:Neonatal adrenoleukodystrophy. 242 Sep 40

Three patients affected by infantile Refsum disease are described with mental retardation, minor facial dysmorphia, chorioretinopathy, sensorineural hearing deficit, hepatomegaly, failure to thrive and hypocholesterolaemia. Initially, only an accumulation of phytanic acid was thought to be present. More recent findings showed a biochemical profile very similar to that found in classical Zellweger syndrome or neonatal adrenoleukodystrophy. Morphologically typical peroxisomes were absent in the liver. All three disorders are associated with multiple peroxisomal dysfunction. Because of these similarities pertinent clinical data of our three patients are compared with those of reported patients diagnosed as having infantile Refsum disease, neonatal adrenoleukodystrophy or Zellweger syndrome who survived for several years. Attention is drawn to the difference in severity of clinical features, ranging from infantile Refsum's disease to neonatal adrenoleukodystrophy and, finally, to Zellweger syndrome.
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PMID:Infantile Refsum disease: an inherited peroxisomal disorder. Comparison with Zellweger syndrome and neonatal adrenoleukodystrophy. 244 76

Progresses in biochemistry permit one to distinguish three biochemical forms of Zellweger Syndrome: 1) hyperpipecolic acidemia, 2) neonatal adrenoleukodystrophy, and 3) infantile Refsum's disease, which have similar clinical manifestations. A seven-month-old male patient with Zellweger Syndrome is presented. He had absence of peroxismes in the liver and elevated pipecolic acids and abnormal levels of bile acids in the blood. The child had a typical neurologic clinical manifestation with hepatomegaly. The ophthalmoscopy revealed grey disks and retinitis pigmentosa with extinguished ERG and law and delayed VEP. The importance of the constant retinal involvement in Zellweger Syndrome is discussed.
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PMID:Zellweger syndrome, retinal involvement. 262 5

We reported two siblings of Leber's congenital amaurosis associated with increased level of very long chain fatty acid (VLCFA) in blood. Case 1, a 3 1/2-year-old boy had congenital blindness, severe psychomotor retardation, hepatomegaly, profound hypotonia, loss of deep tendon reflexes, muscular atrophy and weakness, and non-convulsive status epilepticus characterized by a sudden respiratory failure, and also showed a flat electroretinogram, non-pigmentary retinal degeneration, severe atrophy of the brain stem and cerebellum, hepatic fibrosis, decreased motor and sensory conduction velocities and atlanto-axial instability. Sural nerve biopsy revealed severely decreased number of total myelinated fibers without remarkable demyelination or remyelination. Case 2, an elder sister of case 1, with pigmentary retinal degeneration, hepatomegaly and pericarditis had died at 3 months. Autopsy revealed hypomyelination and heterotopy of the cerebral white matter, hepatic fibrosis, renal microcysts and normal adrenal cytoarchitecture. In case 1, the level of VLCFA was increased twofold and sevenfold of controls in serum and in red cell membrane, respectively. Phytanic or trihydroxycholestanoic acid was not detected in the serum and bile. Normal shaped peroxisomes were definitely recognized in biopsied liver by means of electronmicroscopic histochemistry. From the above findings, these patients was thought to be a new variant of peroxisomal disorders relating to degradation of VLCFA, other than Zellweger syndrome, infantile Refsum disease and infantile adrenoleukodystrophy. It was concluded that peroxisomal functions should be studied in cases of Leber's congenital amaurosis.
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PMID:[Two siblings of Leber's congenital amaurosis with an increase in very long chain fatty acid in blood: relationship between peroxisomal disorders and Leber's congenital amaurosis]. 278 58

The cerebrohepatorenal (Zellweger) syndrome is a fatal autosomal recessive disorder manifested in the neonatal period by profound hypotonia, psychomotor retardation, dysmorphic features, and an enlarged liver. In this study we demonstrate fivefold or greater increases of very-long-chain fatty acid levels, particularly hexacosanoic acid (C26:0) and hexacosenoic acid (C26:1), in plasma and cultured skin fibroblasts from 20 patients. Similar findings in cultured amniocytes from 3 of 14 women in whom the fetus was at risk of the Zellweger syndrome permitted prenatal diagnosis. Oxidation of very-long-chain fatty acids, which normally takes place in the peroxisome, was impaired in homogenates of cultured skin fibroblasts and amniocytes. This observation extends the evidence that the Zellweger syndrome belongs to the newly formulated category of peroxisomal disorders. The pattern of excess very-long-chain fatty acids differs from that demonstrated previously in patients with childhood adrenoleukodystrophy. The study of very-long-chain fatty acids provides a convenient method for the early diagnosis and prenatal detection of the Zellweger syndrome.
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PMID:The cerebrohepatorenal (Zellweger) syndrome. Increased levels and impaired degradation of very-long-chain fatty acids and their use in prenatal diagnosis. 670 9

An eleven month-old boy presented clinically with craniofacial dysmorphia, severe psychomotor retardation, neurological deterioration, no response to visual and acoustic stimuli, failure to thrive, hepatomegaly and adrenal insufficiency. Specific biochemical markers for a peroxisomal deficiency disorder (Zellweger's syndrome, neonatal adrenoleukodystrophy, infantile Refsum's disease) revealed pathological results for very long chain fatty acids, phytanic acid, pristanic acid, plasmalogen biosynthesis and catalase, thus confirming the clinical diagnosis. Comparison of clinical and biochemical findings in the patient with the characteristics of the three peroxisomal deficiency disorders showed overlapping with each of these disorders, which corresponds to the current view that these three peroxisomal disorders differ only with respect to onset and severity of the clinical manifestations, but not with regard to the biochemical defects.
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PMID:[Zellweger syndrome, neonatal adrenoleukodystrophy or infantile Refsum's disease in a case with generalized peroxisome defect?]. 768 5

Effects of several classes of peroxisomal proliferators on peroxisomal functions, hepatomegaly, hepatocarcinogenesis and lipid metabolism have been extensively investigated in rodents. Less is known about influences of these agents, some used as hypolipidemic drugs, on various metabolic parameters in humans. We examined effects of clofibrate, di(2-ethyl-hexyl)phthalate (DEHP) and pirinixic acid (WY-14,643) on phospholipid metabolism in human fibroblasts in culture. Clofibrate inhibited incorporation of [1-14C]hexadecanol and [1-14C]linolenic acid into ethanolamine phosphoglycerides in a time- and concentration-dependent manner; labeling of plasmalogens and non-plasmalogen ethanolamine phosphoglycerides was reduced by 40-80% compared to a generalized 10-30% inhibition of labeling of other phospholipids, including phosphatidylcholine. In pulse and pulse-chase experiments, selective inhibition of incorporation of [1,2-14C]ethanolamine, compared to [methyl-3H]choline, confirmed relative specificity of inhibition of ethanolamine phosphoglycerides. Similar concentration dependence and specificity for inhibition of phospholipid turnover was observed for DEHP and WY-14,643, in both control and mutant (Zellweger and adrenoleukodystrophy) fibroblasts, in the absence of major effects on peroxisomal markers. These observations that peroxisomal proliferators specifically inhibit ethanolamine phosphoglyceride turnover in human fibroblasts should be considered when assessing the efficacy and safety of such agents as hypolipidemic drugs or when evaluating mechanisms of proliferator action at the cellular level.
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PMID:Clofibrate and other peroxisomal proliferating agents relatively specifically inhibit synthesis of ethanolamine phosphoglycerides in cultured human fibroblasts. 791 96

At least 21 genetic disorders have now been found that are linked to peroxisomal dysfunction. Whatever the genetic defect might be, peroxisomal disorders should be considered in various clinical conditions, dependent on the age of onset. The prototype of peroxisomal disorders is represented by 'classical' Zellweger syndrome (ZS) which is the most severe disorder combining all the characteristic symptoms. ZS is characterized by the association of errors of morphogenesis, severe neurological dysfunction, neurosensory defects, regressive changes, hepatodigestive involvement with failure to thrive, usually early death, and absence of recognizable liver peroxisomes. Other peroxisomal disorders (pseudo-Zellweger syndrome, neonatal adrenoleukodystrophy (NALD), pseudo-neonatal adrenoleukodystrophy, rhizomelic chondrodysplasia punctata (RCDP), and hyperpipecolic acidaemia) share some of these symptoms, but with varying organ involvement, severity of dysfunction, and duration of survival. The diagnosis should not cause difficulty when all the characteristic manifestations are present. Depending on the main presenting sign, peroxisomal disorders in neonates should be suspected in two categories of circumstances: polymalformative syndrome with craniofacial dysmorphism, and severe neurological dysfunction. During the first 6 months of life, the predominant symptoms may be hepatomegaly, prolonged jaundice, liver failure, anorexia, vomiting and diarrhoea leading to failure to thrive resembling a malabsorption syndrome; severe psychomotor retardation, hearing loss and ocular abnormalities become evident. Beyond 4 years of age, behavioural changes, intellectual deterioration, visual impairment and gait abnormalities may be the presenting symptoms. Independently of the clinical symptoms and age of onset, most peroxisomal disorders described so far can be clinically screened by recordings of electroretinogram, visual-evoked responses, and brain auditory-evoked responses, which are almost always abnormal. Nine of the 17 peroxisomal disorders with neurological involvement are associated with an accumulation of very long-chain fatty acids (VLCFA), which suggests that assay of plasma VLCFA should be used as a primary test. However, assays of plasma phytanic acid and plasma/urine bile acid intermediates should also be performed in view of the recent reports of atypical chondrodysplasia variants (without rhizomelic shortening) and isolated trihydroxycholestanoic aciduria. The differential diagnoses in various clinical conditions and age periods are discussed.
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PMID:Clinical approach to inherited peroxisomal disorders. 905 44


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