RESUMO
The 15q13.3 heterozygous microdeletion is a fairly common microdeletion syndrome with marked clinical variability and incomplete penetrance. The average size of the deletion, which comprises six genes including CHRNA7, is 1.5 Mb. CHRNA7 has been identified as the gene responsible for the neurological phenotype in this microdeletion syndrome. Only seven patients with a homozygous microdeletion that includes at least CHRNA7, and is inherited from both parents have been described in the literature. The aim of this study was to further describe the distinctive eye manifestations from the analysis in the three French patients diagnosed with the classical 1.5 Mb homozygous microdeletion. Patients' ages ranged from 30 months to 9 years, and included one sib pair. They all displayed a remarkably severe identifiable clinical phenotype that included congenital blindness and convulsive encephalopathy with inconstant abnormal movements. The ophthalmological examination revealed a lack of eye tracking, optic nerve pallor, an immature response with increased latencies with no response to the checkerboard stimulations at the visual evoked potential examination, and a distinctive retina dystrophy with a negative electroretinogram in which the "b" wave was smaller than the "a" wave after a dark adapted pupil and bright flash in all patients. Clear genotype-phenotype correlations emerged, showing that this eye phenotype was secondary to homozygous deletion of TRPM1, the gene responsible for autosomal recessive congenital stationary night blindness. The main differential diagnosis is ceroid lipofuscinosis.
Assuntos
Cegueira/genética , Transtornos Cromossômicos/genética , Deficiência Intelectual/genética , Lipofuscinoses Ceroides Neuronais/genética , Convulsões/genética , Canais de Cátion TRPM/genética , Receptor Nicotínico de Acetilcolina alfa7/genética , Criança , Pré-Escolar , Deleção Cromossômica , Transtornos Cromossômicos/patologia , Cromossomos Humanos Par 15/genética , Eletrorretinografia , Olho/patologia , Anormalidades do Olho/genética , Oftalmopatias Hereditárias/genética , Feminino , Estudos de Associação Genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Deficiência Intelectual/patologia , Masculino , Miopia/genética , Lipofuscinoses Ceroides Neuronais/patologia , Cegueira Noturna/genética , Nervo Óptico/anormalidades , Distrofias Retinianas/genética , Convulsões/patologiaRESUMO
The objective of the present study was to evaluate the effect of a paediatric tube feed supplemented with a multifibre mixture on the gut microbiota and nutritional and micronutrient status of children on long-term enteral nutrition (EN). A randomised, controlled, double-blind, cross-over trial (2 × 3 months) with a washout period of 1 month was carried out. Twenty-seven children (80% neurologically impaired) aged 11.9 (SD 3.9) years, on long-term EN (4.8 (SD 3.9) years) were recruited. The analyses of the children's faecal pH, microbiota along with anthropometric measures, bowel movements and markers of blood micronutrient status were made. Twenty children completed the study. A significant increase in the proportion of stool bifidobacteria (+16.6%, P < 0.05) was observed during the multifibre period than during the fibre-free period, together with a significant reduction in stool pH (P < 0.001). Stool frequency and consistency as well as growth did not differ between the two periods. There was a significant increase (P < 0.05) in plasma ferritin at the end of the fibre-free period, but plasma ferritin levels remained within normal ranges during both periods. No diet effects on other blood parameters were observed. In conclusion, addition of a multifibre mixture with prebiotic components to paediatric EN is well tolerated, promotes bifidobacteria and reduces stool pH, indicating an improved gut health.
