[Pulmonary involvement in acute febrile neutrophilic dermatosis (Sweet's syndrome)].

We encountered a 55-year-old man with pulmonary involvement in acute febrile neutrophilic dermatosis (Sweet's syndrome). He had been treated with steroids for Sweet's syndrome for 2 years, and on September 17, 1998 presented with a cough and a fever of 38.9 degrees C. Physical examination revealed fine crackles at the bases of both lungs. Chest radiography and computed tomography demonstrated reticular and nodular infiltrates in both lungs. Treatment with a variety of antibiotic agents and an antifungal agent was not effective. Sputum culture was sterile and bronchial washings were negative for infectious pathogens. Transbronchial biopsy revealed a mild chronic interstitial infiltrate and an inflammatory exudate in bronchiolo-alveolar tissue. The pulmonary lesions and cutaneous lesions were resolved by intradermal injections of triamcinolone acetonide in addition to oral prednisolone. Although the apparent neutrophilic infiltrates cited by earlier reports were not observed in transbronchial biopsy specimens, the clinical course in this case suggested that our patient had Sweet's syndrome with pulmonary involvement.