Abstract
Purpose
C-reactive protein (CRP) and white blood cell (WBC)-count are routine blood chemistry parameters in monitoring infection. Little is known about the natural history of their serum levels in conservative and operative spondylodiscitis treatment.
Methods
Pre-and postoperative serum levels of CRP and WBC-count in 145 patients with spondylodiscitis were retrospectively assessed. 104 patients were treated by debridement, spondylodesis and an antibiotic regime, 41 only with a brace and antibiotics. The results of the surgical group were compared to 156 patients fused for degenerative disc disease (DDD) .
Results
Surgery had a significant effect on peak postoperative CRP-levels. In surgically managed patients CRP peaked at 2-3 days after surgery (spondylodiscitis: pre-OP: 90 mg/dl vs. post-OP day 2-3: 146 mg/dl; DDD: 9 mg/dl vs.141 mg/dl; p<0,001), followed by a sharp decline. Although values were higher for spondylodiscitis patients, dynamics of CRP values were similar in both groups. Non-operative treatment showed a slower decline. Surgically managed spondylodiscitis showed a higher success rate in identifying bacteria. Specific antibiotic treatment led to a more predictable decline of CRP values. WBC did not show an interpretable profile.
Conclusion
CRP is a predictable serum parameter in patients with spondylodiscitis. WBC-count is unspecific. Initial CRP increase after surgery is of little value in monitoring infection. A preoperative CRP value, and control once during the first 3 days after surgery is sufficient. Closer monitoring should then be continued. Should a decline not be observed, therapy needs to be scrutinized, antibiotic treatment reassessed and concomitant infection contemplated.