Yeast opsonization defect and immunoglobulin deficiency in severe infantile dermatitis (Leiner's disease).

The defect in Leiner's disease, which presents in early infancy with extensive dermatitis, diarrhoea, and failure to thrive, has been attributed to a defect of the fifth component of complement (C5). We report 2 brothers with extensive dermatitis and dysgammaglobulinaemia. Both died. The older showed symptoms of Leiner's disease: C5 tests were not performed. The younger had extensive dermatitis and was found to have the C5 defect. He developed normally, but died suddenly with pertussis. We postulate that the C5 defect is not the sole cause of Leiner's disease as has been suggested, but that hypogammaglobulinaemia or other lymphoid deficiency is also required for its expression.