The clinical use of erythrocyte sedimentation rate in pyogenic vertebral osteomyelitis.

STUDY DESIGN: Retrospective chart review of 44 cases.

OBJECTIVE: To describe the clinical usage of the erythrocyte sedimentation rate in pyogenic vertebral osteomyelitis.

SUMMARY OF BACKGROUND DATA: The erythrocyte sedimentation rate is often used to determine the efficacy and duration of treatment in pyogenic vertebral osteomyelitis. Although consensus and anecdotal reports support this notion, no detailed review of the erythrocyte sedimentation rate response in conservative treatment of pyogenic vertebral osteomyelitis has been made, to date.

METHODS: For 44 patients with pyogenic vertebral osteomyelitis who had erythrocyte sedimentation rate testing at or before the time of diagnosis and at least twice during the next month, the clinical findings and results of the erythrocyte sedimentation rate testing were reviewed.

RESULTS: Of 18 cases with no significant fall in the erythrocyte sedimentation rate during the first month, 9 (50%) failed conservative treatment. Conversely, of the 26 cases with a good erythrocyte sedimentation rate response during the first month, three (12%) were clinical failures. However, a rapid decline of the erythrocyte sedimentation rate (> 50% in the first month) is rarely seen in treatment failure. In addition, approximately 2 weeks after antibiotic treatment, 19 of 32 were actually higher than at the time of diagnosis, but went on to clinical cure without surgery. The erythrocyte sedimentation rate, in combination with the patient's age and immune status, predicted the success of antibiotic treatment, in most cases. The erythrocyte sedimentation rate response alone during the first month was not a clear predictor of success.

CONCLUSIONS: Although the erythrocyte sedimentation rate does correlate well with response to treatment as a general rule, care must be taken in interpretation of a persistently elevated or even rising erythrocyte sedimentation rate as an isolated clinical finding.