RESUMEN
BACKGROUND: In France, neonatal screening of phenylketonuria (PKU) started in 1966. A national association was created in 1978 in order to organise the neonatal screening program and to control the efficacy of the screening and patients' follow-up. AIMS: To evaluate the results of the French PKU screening program in terms of hyperphenylalaninaemia epidemiology, efficacy of the screening procedure, management and outcome of the patients. STUDY DESIGN: The national database has been filled-up first with the answers to questionnaires that were sent each year by the PKU patients' physicians, and second with the results of an additional inquiry, which was set up in 1994 in order to investigate diagnosis, treatment, and school outcome of all French PKU patients. RESULTS: PKU was diagnosed in 81.6% of patients with hyperphenylalaninaemia (HPA), non-PKU HPA in 17.2% and cofactor deficiency in 1.1%. From 1980, incidence of PKU has been stable: 1 per 17,124 live births. Sensitivity of the screening procedure was 99.3%. Age at diet initiation regularly decreased to reach 14 days as a median in 1996. Until 1990, median age at diet discontinuation was 6 years of age. Later, strict diet was continued longer (at least, up to 8-10 years). PKU patients who entered to secondary school at normal age were characterised by an earlier age at diagnosis and at diet initiation and a later age at diet discontinuation, compared to those who entered 1 year or more behind normal age. CONCLUSION: These data confirm the benefit of a nationwide organised screening program. They emphasise the importance of an early neonatal diagnosis and diet initiation in PKU patients and are consistent with the benefit of a longer period of strict diet in childhood.
Asunto(s)
Bases de Datos Factuales , Tamizaje Neonatal , Fenilcetonurias/epidemiología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Alimentos Formulados , Francia/epidemiología , Humanos , Recién Nacido , Masculino , Cooperación del Paciente , Fenilcetonurias/dietoterapia , Fenilcetonurias/fisiopatología , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
Complex III (CIII; ubiquinol cytochrome c reductase of the mitochondrial respiratory chain) catalyzes electron transfer from succinate and nicotinamide adenine dinucleotide-linked dehydrogenases to cytochrome c. CIII is made up of 11 subunits, of which all but one (cytochrome b) are encoded by nuclear DNA. CIII deficiencies are rare and manifest heterogeneous clinical presentations. Although pathogenic mutations in the gene encoding mitochondrial cytochrome b have been described, mutations in the nuclear-DNA-encoded subunits have not been reported. Involvement of various genes has been indicated in assembly of yeast CIII (refs. 8-11). So far only one such gene, BCS1L, has been identified in human. BCS1L represents, therefore, an obvious candidate gene in CIII deficiency. Here, we report BCS1L mutations in six patients, from four unrelated families and presenting neonatal proximal tubulopathy, hepatic involvement and encephalopathy. Complementation study in yeast confirmed the deleterious effect of these mutations. Mutation of BCS1L would seem to be a frequent cause of CIII deficiency, as one-third of our patients have BCS1L mutations.
Asunto(s)
Encefalopatías/genética , Complejo III de Transporte de Electrones/genética , Transporte de Electrón , Túbulos Renales Proximales/patología , Fallo Hepático/genética , Mitocondrias/genética , Mutación , Proteínas/genética , ATPasas Asociadas con Actividades Celulares Diversas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Encefalopatías/patología , Femenino , Humanos , Recién Nacido , Fallo Hepático/patología , Masculino , Datos de Secuencia Molecular , Proteínas/química , Homología de Secuencia de AminoácidoRESUMEN
We describe 4 cases of lysinuric protein intolerance, which all fulfilled the diagnostic criteria for hemophagocytic lymphohistiocytosis. Mature histiocytes and neutrophil precursors participated in hemophagocytosis in the bone marrow. Moreover, serum levels of ferritin and lactate dehydrogenase were elevated, hypercytokinemia was present, and soluble interleukin-2 receptor levels were increased up to 18.6-fold. The diagnosis of lysinuric protein intolerance should therefore be considered in any patient presenting with hemophagocytic lymphohistiocytosis.