CONGENITAL ALVEOLAR PROTEINOSIS - HEREDIT ARY SURFACTANT PROTEIN-B DEFICIENCY

A term female neonate born to healthy, unrelated parents developed sig ns of respiratory distress shortly after birth, requiring intubation a nd mechanical ventilation with high inspiratory oxygen concentrations. The chest X-ray showed diffuse reticular opacities with predominance in the more central areas. Neither exogenous surfactant therapy or sys temic steroids had any effect. An open lung biopsy suggested alveolar proteinosis. Surfactant analyses in broncho-alveolar lavage and geneti c investigations in the patient and her parents helped to establish th e diagnosis of congenital surfactant protein B deficiency. The patient died of respiratory failure at 8 weeks of age. In congenital surfacta nt protein B deficiency, mutations in the SFTP3-gene on chromosome 2 ( which encodes SP-B) result in a disturbance in both surfactant homeost asis and -function which is not amenable to therapy. In families where such mutations are known, e.g. the 121ins2 mutation, the diagnosis ca n already be established antenatally.