Response of C-reactive protein after craniotomy for microsurgery of intracranial tumors.

Objective: C-reactive protein (CRP) is used as an indicator of inflammatory processes. However, its expression is unspecific and will increase after surgery. Without normative data on its regular course after craniotomy, postoperative infection can barely be detected or excluded.

Methods: CRP was measured for 10 days in 46 patients who underwent elective craniotomy for microsurgery of intracranial tumors.

Results: After craniotomy, CRP rapidly increased to reach a peak mean value of 32.43 +/- 38.02 mg/l (P < 0.001) on the second postoperative day. In 39 patients (85%), CRP reached its maximum level within the first 2 days. From Days 3 to 5 after surgery, mean CRP values constantly and significantly declined (P < 0.001) to arrive at a mean of 6.67 +/- 10.80 mg/l) on the fifth postoperative day. On Day 4, the mean CRP level returned to below one-third of the peak value (10.63 +/- 17.08 mg/l). On an individual basis, this was true for 34 patients (74%). During the period of initial increase of CRP until the second postoperative day, there was no significant correlation between CRP and erythrocyte sedimentation rate, body temperature, hemoglobin, hematocrit, red cell count, platelet count, and white cell count. CRP increase was more pronounced with intrinsic brain tumors and was not correlated to the degree of malignancy.

Conclusion: Because CRP can be considerably increased in patients for 4 days after regular intracranial surgery, its diagnostic value during this period is limited. Only prolonged elevation or a secondary increase may indicate an ongoing infection.