IDIOPATHIC BRONCHIOLITIS OBLITERANS ORGANIZING PNEUMONIA (IDIOPATHIC BOOP) IN CHILDHOOD

Idiopathic bronchiolitis obliterans organizing pneumonia (idiopathic B OOP) is a clinicopathological entity of unknown origin first described by Epler and colleagues in 1985. We report our findings from a study of two Japanese boys aged 12 and 13 years with idiopathic BOOP. The pa tients showed no respiratory symptoms nor signs of infection. There wa s no history of exposure to noxious agents or medications in either ca se. Laboratory data, including hematological, biochemical, and immunol ogical tests, were normal, and pulmonary function tests showed only a slight nonprogressive decrease from normal predicted values in vital c apacity and diffusing capacity. Serial radiographs in both cases showe d migration of patchy infiltrates. Fiberoptic bronchoscopy was perform ed for evaluation of eosinophilic pneumonia, but the bronchoalveolar l avage (BAL) revealed no increase in eosinophils and a decrease in CD4/ CD8 ratio in the BAL fluid. Histopathological findings of transbronchi al lung biopsy (TBLB) specimens were compatible with a diagnosis of BO OP. As neither case has shown clinical abnormalities apart from migrat ory patchy infiltrates on chest radiographs, both patients have been o bserved without drug therapy for 3-4 years. (C) 1996 Wiley-Liss, Inc.