[Febrile state and pleural effusion].

A 42 year old patient was admitted for evaluation of a febrile state and left thoracic pain. Chest-X-ray revealed a left-sided pleural effusion nonresponsive to a trial antibiotic treatment. The subsequent punction yielded sterile exudate without microorganisms or malignant cells. Tuberculostatic treatment for suspected tuberculosis lead to exacerbation and hospitalization. Antibodies against native DNA first became detectable during the further course. Together with anamnestic information about fatigue, hair loss and the family history revealing two sisters touched by the disease, the diagnosis of systemic lupus erythematodes was made. Corticosteroids led to rapid improvement with complete resolution of the pleural effusion.