[Familial cardiomyopathy caused by carnitine deficiency]. / Myocardiopathie familiale par déficit en carnitine.

The authors report a familial case of carnitine insufficiency presenting in two out of seven children as a severe, isolated, hypertrophic and hypokinetic cardiomyopathy. The etiology was confirmed by histological study and measurement of carnitine concentrations in the blood and muscle. The evolution was spectacular with specific therapy. Left ventricular hypokinesia regressed completely within 18 months (fractional fibre shortening increased from 10 to 33% and the SCI from 26 to 55% in the more severe of the two cases). Hypertrophy and dilatation decreased significantly. This is a so-called intermediary form of carnitine insufficiency and very unusual because of the isolated cardiac involvement. These cases underline the value of systematic muscle biopsy with measurement of carnitine concentrations in the investigation of all cases of supposed primary cardiomyopathy, especially as a rapid improvement can be obtained by specific replacement therapy.

[Anomalies in fatty acids distribution and superoxide dismutase activity in lymphocytes of an adult with atypical ceroid lipofuscinosis]. / Anomalies de la répartition des acides gras et de l'activité de la superoxyde dismutase dans les lymphocytes d'un adulte atteint de céroïde - lipofuscinose atypique.

A 27-year-old Algerian patient presented a slowly progressive disease clinically characterized by a cerebellar syndrome, absence of deep reflexes, bilateral sign of Babinski, deep sensory disturbances, ophthalmologic disorders and pes cavus. The diagnosis of ceroid lipofuscinosis resulted from the presence of lipofuscin deposits evidenced as autofluorescent bodies, and a particular type of curvilinear, crystalloid ultrastructural inclusion bodies in muscle, lymphocytes and liver. Biochemical tests showed reduction in levels of linoleic and arachidonic acids, and of superoxide dismutase activity in lymphocytes. These findings suggest that the biochemical anomalies result from disturbances in polyunsaturated fatty acids metabolism. These results can be related to pathogenetic hypotheses for ceroid lipofuscinosis suggesting a predominant role for peroxidation of fatty acids.

[Myocardiopathy with lipid overload and leukocyte palmityl carnitine transferase (PCT) deficiency]. / Myocardiopathie avec surcharge lipidique et déficit en palmityl carnitine transférase (PCT) leucocytaire.

Histological changes of the skeletal muscle with moderate fatty infiltration and varied abnormalities of the muscle fibres and conjunctivo-vascular tissue were demonstrated in three adult patients with apparently primary cardiomyopathy with dilatation. Leukocyte PCT activity was decreased and plasma carnitine was increased. In two cases, postmortem cardiac biopsy showed a massive accumulation of lipids and an intense progressive fibrosis dissociating the atrial and ventricular cardiac fibres. A disturbance of lipid metabolism could be the cause of this cardiac and skeletal muscle disease, but the reduced PCT activity could be a sign of more diffuse myocardial disease as suggested by the fibrous lesions and vascular abnormalities observed in our cases. These cases emphasise the value of routine investigation of PCT activity in primary cardiomyopathy and of ultrastructural studies of skeletal muscle, even in the absence of clinical involvement, which may show relatively severe changes reflecting the state of the myocardium.

Lipid composition in liver and brain of genetically obese (ob/ob), heterozygote (ob/+)and normal (+/+) mice.

Lipid composition was studied in liver and brain of normal (+/+), heterozygote (ob/+) and obese (ob/ob) mice. It was found that this genetic defect is expressed differently in the lipid composition of these organs. Cholesterol is increased in liver but strongly decreased in brain of obese animals. Phosphatide fatty acid composition is modified in liver and not in brain. In contrast, phospholipids and total ganglioside sialic acid are affected similarly in both organs. Although clinically normal, heterozygote (ob/+) mice already show an abnormal lipid composition in liver and brain. The potential importance of these results is presented.

[A new form of the Lesch-Nyhan syndrome. A study of hypoxanthine-guanine-phosphoribosyl-transferase in fibroblasts. The in vitro and in vivo effect of adenine on enzyme activity]. / Une nouvelle mutation du syndrome de Lesch-Nyhan. Etude de l'hypoxanthine-guanine-phosphoribosyl-transférase dans les fibroblastes. Effet de l'adénine in vitro et in vivo sur l'activité enzymatique.

A new, clinically and biochemically atypical case of Lesch-Nyhan syndrome is presented. There is mild neurological involvement, the APRTase activity is normal, despite a raised PRPP concentration and HGPRTase activity is low. The optimal pH and temperature of fibroblast HGPRTase activity differ markedly from control values. The Km for hypoxanthine and PRPP are minimally changed. Erythrocyte HGPRTase activity does not vary following adenine ingestion in either the adult patient or the control. Fibroblast HGPRTase activity is not affected by the addition of adenine to cultures of fibroblasts. However, in the child suffering from classical Lesch-Nyhan syndrome, erythrocyte HGPRTase activity decreases following adenine ingestion.

[Erythrocyte phospholipids in Duchenne muscular dystrophy (author's transl)]. / Etude de la composition des phospholipides érythrocytaires dans la myopathie de Duchenne de Boulogne.

The different fractions of erythrocyte phospholipids determined in eleven patients suffering from Duchenne muscular dystrophy and in six possible or probable heterozygous carriers do not differ significantly from those observed in controls. Distribution of their fatty acids shows a reduced amount of palmitoleic acid (C16 : 1) in total fatty acids, in sphingomyelin and phosphatidylethanolamine. The same anomaly is observed, but less significant, in the heterozygous carriers. The C20 : 0 acid is increased in sphingomyelin. Some overlap occurs between results determined in hemizygous or in heterozygous carriers and in controls. These anomalies in fatty acid distribution, if confirmed, may help a better understanding of the pathogenesis of the disease and perhaps be useful to its detection.

[A new family with mutation of the structural gene of human ornithine carbamoyltransferase]. / Une nouvelle famille avec mutation du gène de structure de l'ornithine carbamyltransférase humaine.

Studies of a child with hyperammonemia have demonstrated a deficiency in OCTase. The kinetic properties of the enzyme were studied and it could be shown that we have to deal with a new mutation which is different from the ones previously known. It is a mutation of the structural gene. The detection of a heterozygote is possible when the urinary orotic acid excretion is studied after a loading meal (2g of proteines per kilo of weight). A child with hyperammonaemia due to ornithine transcarbamylase deficiency is described. A new structural gene mutation is probable because the kinetic properties of the enzyme are different to previously described variants. The heterozygote could be detected by the measurement of the excretion of orotic acid in the urine following a protein load of 2 g/Kg.