The Diagnostic and Antibiotic Reference Values of Procalcitonin for Intracranial Infection After Craniotomy

To evaluate values of cerebrospinal fluid (CSF) and serum procalcitonin (PCT) for diagnosis of intracranial infection after craniotomy and relationship between them and to explore value of PCT in guiding clinical use of antibiotics. The incidence of intracranial infection in 21 patients undergoing craniotomy was reviewed. CSF samples and venous blood were collected for analysis. Diagnostic parameters were calculated via receiver operating characteristic curves, and inflammatory indicators were analyzed before and after administration of antibiotics in the infection group. As a control group, 32 patients without infection were recruited for the same measurements. CSF and serum PCT levels in the infection group were higher than levels in the noninfection group (P < 0.05), and diagnostic efficiency of CSF PCT (area under the curve = 0.86, diagnostic odds ratio = 41.40) was superior to serum PCT (area under the curve = 0.66, diagnostic odds ratio = 3.40). Diagnostic efficiency was more powerful when serial testing was used (specificity = 0.99, positive likelihood ratio = 37.10, diagnostic odds ratio = 54.45). All inflammatory indicators decreased after administration of antibiotics except CSF protein (P = 0.129), and no obvious correlation was seen between CSF and serum PCT. Dynamic change of PCT can be used as a reference for adjusting antibiotics. CSF PCT can also be used as an indicator to identify intracranial infection with gram-negative bacteria. CSF PCT is a good marker for intracranial infection and could be used to help confirm intracranial infection and provide guidance for clinical use of antibiotics when combined with serum PCT.