RESUMEN
INTRODUCTION: A combination of disk space narrowing and vacuum phenomenon on radiographs of the spine is usually considered a reliable indicator of degenerative disk disease. We report a case in which vacuum phenomenon was related to Clostridium perfringens discitis. METHODS: A 79-year-old woman was admitted for inflammatory low back pain that had worsened steadily over the last 2 months. Her body temperature was normal, laboratory tests showed inflammation (erythrocyte sedimentation rate, 61 mm/h; and C-reactive protein, 13 mg/L), and blood cultures were negative. Imaging studies (radiographs, computed tomography [CT], and magnetic resonance imaging) indicated L4-L5 discitis. Vacuum phenomenon within the L4-L5 disk was seen on radiographs and CT scans. C. perfringens was recovered by fine-needle biopsy of the disk. Diverticular disease of the colon was the only identifiable portal of entry. Amoxicillin therapy ensured a full recovery. DISCUSSION: C. perfringens discitis is rare, with only 7 published cases in humans. A gastrointestinal portal of entry was identified in 70% of cases. Radiographs or CT scans visualized vacuum phenomenon in 80% of cases. Positive blood cultures were noted in 75% of cases. The outcome was favorable with antibiotic therapy, even when a single-drug was used. The other characteristics of C. perfringens discitis were indistinguishable from those of discitis caused by the usual organisms. CONCLUSION: Presence of gas within the disk does not rule out infectious discitis and may indicate C. perfringens discitis.