Bilateral empyema caused by adult-onset still's disease

Empyemas are usually of infectious origin. Noninfectious causes of empyema may be a considerable diagnostic challenge, as exemplified in the present case report. A 21-year-old male presented with high fever, sore throat and myalgias of 1 week duration. In the following days, bilateral pleural effusions developed, with cellular counts in the pleural fluid up to 117 × 10⁹/liter (98% neutrophils). Despite institution of empiric antibiotic therapy, spiking fever continued. All culture studies resulted in being negative. Following the report of a serum ferritin concentration of 6,975 μg/l, adult-onset Still's disease was diagnosed and successfully treated with anti-inflammatory drugs. This case adds adult-onset Still's disease to the list of noninfectious causes of empyema and underlies the value of measuring serum ferritin as a diagnostic tool.