Diagnostic problems in chronic eosinophilic pneumonia.

To identify the problems involved in the diagnosis of chronic eosinophilic pneumonia (CEP), clinical findings were analysed for 43 patients diagnosed clinically or pathologically with CEP during the past 10 years. About 28% of patients showed peripheral blood eosinophilia and a typical pattern of pulmonary oedema on chest X-ray at initial examination. Eosinophilia was demonstrated in peripheral blood in 86% of patients, in bronchoalveolar lavage (BAL) in 100%, and in transbronchial lung biopsy (TBLB) specimens in 64% of patients. Peripheral blood tests, BAL, and TBLB were all positive for eosinophilia in 60% of patients. BAL was the single test most likely to be positive among the diagnostic tests used in the present study. When CEP is suspected clinically, an understanding of which site is examined by each of the diagnostic tests and of the likelihood of a positive result in each test will facilitate the selection of the most appropriate tests for individual patients.