Spinal abscess and spondylitis due to actinomycosis

Study Design. Report of a rare case of spinal actinomycosis in a young immunocompetent woman. Objective. To show the difficulties in diagnosing spinal actinomycosis. Summary of Background Data. Spinal actinomycosis is rare and usually occurs as a result of a contiguous (abdominal, pelvic, or thoracic) spread of the infection. This localization represents less than 5% of the infectious sites and was mainly, before the penicillin era, a postmortem discovery. Methods. A case is reported of a 34-year-old Algerian woman who had fever, persistent cough, right-side thoracic pain, and progressive severe back pain. Radiographs, computed tomographic scan, and magnetic resonance imaging demonstrated lytic areas on the vertebral bodies of T11 and T12 and a paravertebral mass, without disk involvement. A surgical biopsy of T12 and the paravertebral abscess was performed. Results. Presence of characteristic sulfur granules and gram-positive filamentous bacteria in surgical biopsy tissues and isolation of Actinobacillus actinomycetemcomitans in cultures led to the diagnosis of vertebral actinomycosis. The patient was virtually free of pain and fever after a 3-month regimen of ofloxacin and rifampicin (Rifadine, Marion-Merell, France) and was without recurrence after 18 months of follow-up. Conclusions. Actinomycosis of the spine, caused by the spread of a paraspinal abscess, is extremely rare. The previously poor prognosis has been transformed by antibiotics.