Heterozygous ABCA3 mutation associated with non-fatal evolution of respiratory distress.

A boy without symptoms up to 12 months of age started with persisting cough followed by respiratory failure at 18 months of age, resulting in mechanical ventilation because of alveolar proteinosis. Lung biopsy showed PAS-positive material. PCR was negative for CMV, Pneumocystis jiroveci and adenovirus. BALF showed mature SP-B. Analysis of the ATP-binding cassette transporter A3 (ABCA3; OMIM 601615) gene showed a compound heterozygous mutation from paternal W1148X and maternal T1114A. Alveolar lavage with 720 mg of bovine surfactant allowed weaning from ventilator support. Heterozygous mutation in the ABCA3 gene could be associated with a milder evolution as compared to the homozygous frequently lethal evolution.