[Neonatal screening of congenital toxoplasmosis. Prospective study]. / Depistage neonatal de la toxoplasmose congenitale: etude prospective.

BACKGROUND: While toxoplasmosis infection in women is often benign, transmission of maternal infection to the fetus can lead to severe sequelae. Because the majority of patients with acute toxoplasmosis are asymptomayic, a systematic serologic screening program will needed with monthly serologic screening of all seronegative pregnant women until delivery. The aim of this study was to identify cases of congenital toxoplasmosis among all live births of women found to be seronegative in pregnancy once at least. METHODS: During a prospective study period of 16 months (from 07/02/2003 to 30/06/2004) we conduct a neonatal screening of all live births of women found to be seronegative in pregnancy once at least. Peripheral samples were obtained from every couple mother/infant. Serological methods performed for diagnosis of toxoplasma specific IgM and IgG antibodies were Hemaglutination and Enzyme-linked immunosorbent assay (ELISA). RESULTS: Four cases of congenital toxoplasmosis were diagnosed after birth. All cases were asymptomatic and a specific treatment was started soon after diagnosis. The clinical and serologic evolution was normal in three cases. A serologic rebound at two years was reported in one case with a chorioretinitis in the examination of the ocular fundus. CONCLUSION: Neonatal as well maternal screening during pregnancy and at birth should be systematic to prevent, diagnose and treat early the affected neonates usually asymptomatic.

Foetus-in-fetu: an unusual cause of abdominal mass in the newborn.

Foetus-in-fetu (FIF) is a rare congenital condition in which a vertebrate foetus is incorporated within its twin. The authors report the case of a newborn girl with prenatal ultrasonographic diagnosis of an intra-abdominal mass. Abdominal ultrasonography and computed tomography of the abdomen showed a heterogeneous cystic mass containing multiple calcifications. The patient had a laparotomy at 18 days of age with excision of a well-encapsulated 6 x 5 cm retroperitoneal mass, containing many organs. Anatomicopathologic examination showed a relatively well-differentiated FIF attached to an amniotic sac by a rudimentary umbilical cord. Encephalon, coroidal plexus, vertebral bodies, rudimentary limbs, thyroid gland and teeth were identified. The postoperative period was uneventful.

The role of microsomal phospholipids and their fatty acid composition in the control of hepatic metabolism of lignocaine.

1. Sex differences exist in the metabolism of lignocaine by the rat liver. Microsomal phospholipids have been implicated in the control of these sex differences. Induction of diabetes in the male rat abolishes these sex differences. The difference in drug metabolism between the male and female rat is, thus, the same as that between the control and diabetic male rat. 2. By using reconstitution of delipidated male microsomal proteins with male-, female- and diabetic-derived phospholipids as well as synthetic phospholipids, it should be possible to delineate the role of phospholipids in the control of drug metabolism. 3. Female- and diabetes-derived phospholipids decrease the activity of the male-specific lignocaine N-deethylase specifically by between 35 and 52%. 4. Analysis of the phospholipid classes and fatty acid content of the various fractions indicated that stearic acid content was increased and arachidonic acid content decreased in both female- and diabetic-derived lipids as compared to control males. Linoleic acid content was decreased in female- but increased in diabetic-derived lipids as compared to control males. Subsequent correlation to N-deethylase activity, however, rules out all but the arachidonic acid content of the phospholipids as a controlling factor of lignocaine metabolism. 5. Use of synthetic phosphatidylcholine (PC) species for reconstitution indicates that diarachidonyl-PC is the most efficient at activating the N-deethylase and indicates that the degree of unsaturation of the fatty acyl side-chains of PC is of major importance in the regulation of this enzyme activity. 6. The presence of unsaturated fatty acids, and especially arachidonic acid, in the phospholipids is, thus, a major controlling influence on the specific activation of lignocaine N-deethylase in the rat liver.

The effect of lipid composition on the metabolism of lignocaine by a reconstituted mixed function oxidase system from rat liver.

Hepatic microsomal preparations from male and female rats were delipidated by column chromatography following cholate solubilisation. The enzyme activities were reconstituted using known lipids and the vesicle reconstitution method. Enzyme activity was assayed using lignocaine as the substrate for the mixed function oxidase. This substrate gives two products; one which is predominantly found in the male (N-deethylated derivative) and one that is found in approximately equal amounts in both sexes (3-hydroxylated product). Reconstitution of male- but not female-derived enzyme in mixed dilauroylphosphatidylcholine (DLPC)/dilauroylphosphatidylethanolamine (DLPE) vesicles gave a higher N-deethylase activity than if the same enzyme was reconstituted in DLPC vesicles. 3-Hydroxylase activity, which is not sex-dependent, was not affected by DLPE. Microsomal lipids from male animals were more efficient than female-derived lipids in reconstituting N-deethylase activity from both male- and female-derived enzymes. Microsomal lipids were more efficient than DLPC in reconstituting N-deethylase activity from both male- and female-derived enzymes but 3-hydroxylase activity was similar in the two lipids. There is, thus, a sex- and pathway-dependent effect of the lipids: the male-specific N-deethylase pathway is more affected by lipid composition and then more so in the male-derived enzyme. It is possible, therefore, that some of the sex differences in drug metabolism may be related to changes in lipid composition.