Desquamative interstitial pneumonia and antigen-antibody complexes in two infants with congenital rubella.

Desquamative interstitial pneumonia was observed in two infants with the late-onset congenital rubella syndrome. In both infants this unusual lung disease was associated with circulating immunoglobulin M complexes and interstitial pulmonary deposits of IgM by immunofluorescence. Both infants had IgG deficiency. The first child recovered with a reduction in IgM complex levels and synthesis of rubella-specific IgG. The second infant died during the acute phase of his illness at which time there were high serum concentrations of IgM complexes and slightly increased levels of IgG complexes. Delayed maturation of the immune response in congenital rubella may predispose to persistent antigenemia and pulmonary deposition of rubella antigen-containing IgM complexes resulting in an acute form of interstitial pneumonia.