Familial Churg-Strauss syndrome in two sisters.

Churg-Strauss syndrome (CSS) is an uncommon systemic vasculitis with an increase in the number of eosinophils in the peripheral blood and tissues. Its pathogenesis is unknown, and there is no evidence that genetic factors influence susceptibility to this disease. We present a case of familial CSS in two sisters with atopic-type bronchial asthma and negative perinuclear anti-neutrophil cytoplasmic antibody results. We investigated the human leukocyte antigen typing of the sisters and their six living siblings but found no evidence for heritability of CSS. To our knowledge, this is the first report of familial CSS.