[Case of infectious spondylitis presenting as exudative pleural effusion]

A 59-year-old woman with lumbago, presented with cough and right chest pain. Her chest X-ray showed right pleural effusion, and laboratory studies revealed elevated levels of serum C-reactive protein. Right bacterial pleuritis and empyema was diagnosed based on an analysis of the pleural effusion and pus. She was treated with antibiotics and both the right pleural effusion and pus were drained with a chest tube. Staphylococcus aureus was cultured from the pleural effusion and pus. Her fever and chest pain improved after this treatment, however, the lumbago took a sharp turn for the worse. A spinal MRI showed an increased signal intensity at the level of T11-12, thus suggesting a disk space infection and spondylitis with an epidural abscess. Thereafter, she developed left pleural effusion, and the effusion was drained. Her infection was cured with long-term administration of antibiotics. However, the infectious spondylitis relapsed after four months, and she therefore had to undergo surgery. This case suggested that infectious spondylitis produced the exudative pleural effusion. Bacterial pleuritis, empyema and exudative pleural effusion must therefore be treated while keeping in mind the possibility of infectious spondylitis.