Ornithine transcarbamylase deficiency presenting with strokelike episodes

A girl with ornithine transcarbamylase deficiency had a history of recurrent strokelike episodes. The differential diagnosis of unexplained stroke should include primary urea cycle defects.

"Reducing body"-like inclusions in skeletal muscle in childhood-onset acid maltase deficiency

Unusual inclusions with some of the features of "reducing bodies" were encountered in the skeletal muscle biopsy of a 2.5-year-old boy with childhood-onset acid maltase deficiency. The biopsy revealed a vacuolar myopathy with lysosomal storage of glycogen and eosinophilic refractile inclusions in myofibers, which appeared dark blue with the menadione-nitroblue tetrazolium reaction. The significance of the association of inclusions with reducing properties in the setting of acid maltase deficiency is discussed.

Autopsy findings in two siblings with infantile Refsum disease

Recognition of adrenal atrophy during a review of autopsy findings in two sisters who died at 8 months and 3 1/2 years prompted estimation of very long chain fatty acids, phytanic acid and pristanic acid on wet liver fixed in formalin for 12 years. These were shown to be markedly increased and defects in multiple peroxisomal functions and decrease in particulate catalase were shown in cultured fibroblasts, confirming an abnormality of peroxisomal biogenesis. The patients had presented with failure to thrive, recurrent diarrhoea and vomiting, poor mental development, retinal pigmentation, blindness and in the older patient deafness, with only mild dysmorphic features. Autopsy in the older patient showed adrenal atrophy, cirrhosis, and foamy histiocytes in multiple organs. The brain showed no demyelination, little cytoarchitectural abnormality, occasional perivascular histiocytes in the grey matter and meninges and prominent Purkinje cells in the molecular layer of the cerebellum. In the younger patient the changes were very subtle in spite of the marked clinical similarity. Despite the young age at death the clinicopathological features are most suggestive of infantile Refsum disease. In many situations anatomical pathology can be very useful in the recognition and study of peroxisomal disorders.

Heteroplasmic mtDNA mutation (T----G) at 8993 can cause Leigh disease when the percentage of abnormal mtDNA is high

A female infant showing lacticacidemia, hypotonia, and neurodegenerative disease died at 7 mo of age. Autopsy revealed lesions typical of Leigh disease, both in the basal ganglia and in the brain stem. A maternal aunt and uncle died 1 year and 5 mo, respectively, after following a similar clinical course, while another uncle, presently 33 years of age, has retinitis pigmentosa and ataxia and is mentally retarded. PCR restriction-digest analysis of mtDNA isolated from the proband revealed a T-to-G change at position 8993, creating a new AvaI restriction site. The mutation present in the ATP 6 gene results in the substitution of an arginine residue for a leucine. The indexed patient had greater than 95% abnormal mtDNA in her skin fibroblasts, brain, kidney, and liver tissues, as measured by laser densitometry. The maternal aunt who died at age 1 year had greater than 95% abnormal mtDNA in her lymphoblasts. The uncle with retinitis pigmentosa had 78% and 79% abnormal mtDNA in his skin fibroblasts and lymphoblasts, respectively, while an asymptomatic maternal aunt and her son had no trace of this mutation. The mother of the index case had 71% and 39% abnormal mtDNA in her skin fibroblasts and lymphoblasts, respectively, showing that the heteroplasmy can be variable, on a tissue-specific basis, within one individual. This shows that mtDNA mutations at 8993 can produce the clinical phenotype of Leigh disease in addition to the phenotype of ataxia and retinitis pigmentosa described by Holt et al.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathology of hepatic peroxisomes and mitochondria in patients with peroxisomal disorders

The morphology of hepatic peroxisomes in five patients with metabolic disorders believed to be due to inherited defects of peroxisomal function or biogenesis is described. Electron microscopy and cytochemical staining for catalase were used to identify peroxisomes in two boys with infantile Refsum's disease (IRD), a girl with autopsy confirmed neonatal adrenoleukodystrophy (NALD), and two boys with pseudo-Zellweger syndrome (PZS). In the patients with IRD and NALD hepatic peroxisomes were significantly reduced in size and number and contained electron dense centres. In the liver of the patients with PZS the peroxisomes were enlarged. Morphologically abnormal peroxisomes were also detected in autopsy tissue from one boy with PZS using electron microscopy. Lamellar-lipid inclusions and mitochondria with crystalline inclusions and/or abnormal cristae are also described in two patients, one with IRD, the other with NALD.

Choanal atresia as a feature of ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome

We report here a father and daughter with digital abnormalities, nasolacrimal duct obstruction, and variable alopecia. The father had a cleft lip and palate and the daughter had choanal atresia. We propose they both have the EEC syndrome and show the variable expressivity of this disorder. Choanal atresia has not been previously reported in this condition.

A syndrome of epilepsy, dementia, and amelogenesis imperfecta: genetic and clinical features

A family is described with six members affected by a syndrome of epilepsy, dementia, and amelogenesis imperfecta (Kohlschütter's syndrome). An autosomal recessive pattern of inheritance is established for this disorder.

Aspirin therapy in angina pectoris: effects on platelet aggregation, exercise tolerance, and electrocardiographic manifestations of ischemia

If altered platelet function contributes to poorly perfused zones of myocardium in patients with angina pectoris, then specific antiplatelet therapy might improve cardiovascular function and exercise performance. Exercise tolerance on a bicycle ergometer, heart rate-blood pressure product, and ischemic ECG changes at exercise end-point were compared before and during oral aspirin therapy (2.4 Gm. per day for 2 weeks) in 11 normal subjecs and in 11 patients with stable angina pectoris. Platelet aggregation threshold in response to ADP and epinephrine was measured. Untreated patients had increased platelet aggregability when compared to normal subjects...

Effects of mannitol on cardiac ultrastructure and microcirculation following anoxia

Electron microscopic and microcirculatory effects of hyperosmolal mannitol were evaluated in the isolated perfused isovolumic rat heart. Specimens for ultrastructural examination were obtained in 26 experiemnts after 15 min of sequential aerobic, anoxic, and reoxygenated perfusion using an isosmolal perfusate of Krebs-Ringer-Henseleit bicarbonate buffer (KRB) (osmolality equals 290 mosmol/kg) vs. a hyperosmolal solution of KRB + mannitol (equals 350 mosmol/kg). No significant changes were noted during aerobic perfusion. Anoxic hearts perfused with isosmolal KRB demonstrated the most severe ultrastructural alterations including: mitochondrial swelling with disruption of cristae, myofibrillar fusion and contraction bands, and subsarcolemmal edema and vacuolization. These subcellular changes were not only partially reversed by oxygenated isosmolal perfusion but were significantly reversed during both the anoxic and reoxygenation perfusion periods with mannitol added. Following silicone rubber injection of the microcirculation, only focal capillary endothelial cell swelling was noted, and no difference in arteriolar or capillary filling was observed with either perfusate. Thus, mannitol significantly reversed the postanoxic ultrastructural changes consistently observed in the absence of increased osmolality. No gross effect on vascular patency could be demonstrated.

Metabolic and hemodynamic consequences of mannitol following myocardial anoxia

The mechanism of action of hyperosmolal mannitol was evaluated by hemodynamic and metabolic studies in 79 isovolumic nonrecirculating paced perfused rat hearts during sequential 15-min periods of aerobic, anoxic, and reoxygenated perfusion. Hyperosmolality induced by addition of mannitol significantly decreased myocardial water content (wet/dry wt ratio). It improved recovery of hemodynamic function during reoxygenation. With isomolal perfusion (290 mosmol/kg) left ventricular systolic peak pressure (LVSP) decreased 32% (127 +/- 5 to 86 +/- 6 mmHg) and maximum dP/dt fell 50% (3,513 +/- 328 to 1,758 +/- 172 mmHg/s) during the postanoxic recovery period. With hyperosmolal perfusion (350 mosmol/kg), LVSP decreased 23% (132 +/- 5 to 102 +/- 7 mmHg) and dP/dt fell 21% (3,817 +/- 215 to 2,998 +/- 234 mmHg/s) (P less than .01). Hyperosmolal perfusion did not affect postanoxic total coronary flow, lactate and glucose metabolism, tissue glycogen, creatine phsophate, or adenine nucleotide concentrations. Coronary perfusion with hypersmolal solution aided recovery, enhanced postanoxic myocardial performance, and minimized tissue swelling. The most tenable explanation for the locus of action of hyperosmolal mannitol during anoxia under our experimental conditions is its direct effect on myocardial water content.

The effects of hyperosmolal coronary perfusion on the haemodynamic, metabolic and ultrastructural changes of myocardial anoxia

Recovery from anoxia has been evaluated in the isovolumic non-recirculating paced perfused rat heart. Seventy studies were performed consisting of 15 min of aerobic perfusion (AP); AP+15 min anoxic perfusion; and AP+15 min anoxic perfusion+15 min reoxygenation (recovery). Krebs-Ringer-bicarbonate+5 mmol glucose (KRB) (290 mmol) was compared to KRB+mannitol (350 mmol). Mannitol decreased myocardial water content. It improved recovery of haemodynamic function after reoxygenation. With KRB alone left ventricular systolic peak pressure (LVSP) decreased 32% and maximum dP/dt by 50%. With mannitol added LVSP decreased 18% and dP/dt 21% (P<0·01). KRB and mannitol did not differentially affect total coronary flow, lactate and glucose extraction, tissue glycogen, creatine phosphate or adenine nucleotide concentrations.

No difference in submicroscopic appearance was noted with either perfusate during aerobic perfusion. Anoxic hearts perfused with isosmolal KRB demonstrated the most severe ultrastructural alterations including mitochondrial swelling with disruption of cristae and extraction of matrix components, myofibrillar fusion and contraction bands, and subsarcolemmal oedema and vacuolization. These changes were only partially reversed during reoxygenated perfusion. However, cellular changes were reversed or markedly improved during both the anoxic and reoxygenation perfusion periods with hyperosmolal solutions. When studied by silicone rubber injection of the microcirculation, only focal capillary endothelial cell swelling was noted and no difference in arteriolar or capillary filling was observed with either perfusate. Mannitol appears to improve LV function by direct myocardial osmotic action unrelated to enhanced energy production.