RESUMO
Surfactant protein B encoding gene mutations have been related to early onset fatal respiratory distress in full-term neonates. We report a school-aged male child homozygous for a surfactant protein B encoding gene missense mutation who presented after the neonatal period. His respiratory insufficiency responded to high dose intravenous methylprednisolone and hydroxychloroquine.
Assuntos
Diagnóstico Tardio , Proteinose Alveolar Pulmonar/congênito , Proteína B Associada a Surfactante Pulmonar/deficiência , Criança , Marcadores Genéticos , Homozigoto , Humanos , Masculino , Mutação , Proteinose Alveolar Pulmonar/diagnóstico , Proteinose Alveolar Pulmonar/genética , Proteinose Alveolar Pulmonar/terapia , Proteína B Associada a Surfactante Pulmonar/genéticaRESUMO
The incapacity to synthesize certain components of pulmonary surfactant causes a heterogeneous group of rare respiratory diseases called genetic disorders of surfactant dysfunction. We report a female full-term infant with neonatal respiratory distress of early onset due to inherited SP-B deficiency. The infant failed oxygen weaning at multiple trials. Chest computed tomography was performed on the 29th day of life revealing ground-glass opacities, regular interlobular septal thickening and fine interlobular reticulations. Analysis of genomic DNA showed homozygosity for an extremely rare SFTPB gene variant (c.620A>G, p.Tyr207Cys). Both parents were heterozygotes for the mutation. The diagnosis of congenital SP-B deficiency should be suspected whenever an early and acute respiratory failure in a term or near-term infant does not resolve after five days of age: diagnostic confirmation can be easily and rapidly obtained with the analysis of genomic DNA.