[Pyogenic and non-pyogenic vertebral osteomyelitis: descriptive and comparative study of a series of 40 cases]

To describe the features of vertebral osteomyelitis (VO) in our area, and to compare pyogenic VO (PVO) and non-pyogenic VO (NPVO).

Retrospective study of patients with VO diagnosed in our hospital between january 1992 and december 1998.

We identify 40 patients with VO: 17 (42.5%) with tuberculous VO, 12 (30%) with PVO, 10 (25%) with brucellar VO and 1 (2.5%) with a VO caused by Candida albicans. The mean age was 52.9 years, and 75% of patients were male. Only a 20% of cases had a known immunosuppression. Fever/febricule was present in 55% of patients and vertebral pain in 95%. The more frequent locations were lumbar (67.5%) and dorsal (27.5%). One or more paravertebral or epidural abscesses were present in 67.5% of cases and spinal cord compression was present in 27.5%. An elevated erythrocyte sedimentation rate (ESR) was present in 40% and leukocytosis in 27.5%. Sequelae after complete treatment occurred in 40% of patients, with residual vertebral pain in 37.5%. There was a shorter clinical course and a higher frequency of fever/febricule and leukocytosis in PVO than in NPVO.

In our area the more frequent etiology of VO is tuberculosis. VO occurs predominantly in males older than 50 years, without known immunosuppression, and almost exclusively with lumbar or dorsal locations. The absence of fever/febricule, leukocytosis or elevated ESR do not exclude the diagnosis of VO. Sequelae after complete treatment are relatively frequent, fundamentally residual vertebral pain. There are some differences in the features between PVO and NPVO, which may aid in the differential diagnosis of both entities.