Severe diffuse interstitial pneumonitis induced by carmustine (BCNU).

We report a fatal case of acute interstitial pneumonitis in a patient treated with carmustine (BCNU) for a brain tumor. Bronchoalveolar lavage (BAL) revealed lymphocyte alveolitis with a low CD4/CD8 ratio (0.36), consistent with an immunoallergic phenomenon, rather than the most often evoked toxic hypothesis.