TRANSBRONCHIAL BIOPSY IN PATIENTS WITH PULMONARY EOSINOPHILIC GRANULOMA - COMPARISON WITH FINDINGS ON OPEN LUNG-BIOPSY

We evaluated the findings on transbronchial biopsy specimens in refere nce to open lung biopsy specimens from 12 patients with pulmonary eosi nophilic granuloma. Features in transbronchial biopsy specimens were f urther contrasted to those of patients with interstitial fibrosis and nondiagnostic biopsy specimens for localized lesions. Transbronchial b iopsy specimens were randomized and graded for histologic features and cellularity. Patients with eosinophilic granuloma had more macrophage s (P<.05) but equivalent numbers of eosinophils, neutrophils, and Lang erhans' cells compared with those of the other two groups. Only two en doscopic biopsy specimens were histologically diagnostic or highly con sistent with eosinophilic granuloma. We conclude that the diagnosis of eosinophilic granuloma is possible on transbronchial biopsy but requi res a high index of suspicion. The demonstration of Langerhans' cells by immunohistochemical staining for S100 protein is a useful adjunct. The low diagnostic yield for eosinophilic granuloma on transbronchial biopsy results from inadequate sampling and from the nonspecific appea rance of discrete lesions in small tissue samples.