Pyogenic, tuberculous, and brucellar vertebral osteomyelitis: a descriptive and comparative study of 219 cases.

Objectives: To describe a large series of patients with vertebral osteomyelitis (VO), and to compare the clinical, biological, radiological, and prognostic features of pyogenic (PVO), tuberculous (TVO), and brucellar vertebral osteomyelitis (BVO).
Methods: A retrospective multicentre study, which included 219 adult patients with VO with confirmed aetiology, who were diagnosed between 1983 and 1995 in two tertiary care centres. Of these patients, 105 (48%) had BVO, 72 (33%) PVO, and 42 (19%) TVO.
Results: One hundred and forty eight (67.6%) patients were male and 71 (32.4%) female. The mean (SD) age was 50.4 (16.4) years (range 14-84) and the mean (SD) duration of symptoms before the diagnosis was 14 (16.8) weeks. In 127 patients (57.9%) the vertebral level involved was lumbar, in 70 (31.9%) thoracic, and in 16 (7.3%) cervical. One hundred and nineteen patients (54.4%) received only medical treatment and 100 (45.6%) required both medical and surgical treatment. The presence of diabetes mellitus, intravenous drug abuse, underlying chronic debilitating diseases or immunosuppression, previous infections, preceding bacteraemia, recent vertebral surgery, leucocytosis, neutrophilia, and increased erythrocyte sedimentation rate (ESR) were significantly associated to PVO. A prolonged clinical course, thoracic segment involvement, absence of fever, presence of spinal deformity, neurological deficit, and paravertebral or epidural masses, were significantly more frequent in the group of TVO. The need for surgical treatment and the presence of severe functional sequelae were more frequent in the groups of PVO and TVO.
Conclusion: There are significant clinical, biological, radiological, and prognostic differences between BVO, PVO, and TVO. These differences can point to the causal agent and orient the initial empirical medical treatment while awaiting a final microbiological diagnosis.