Background: The normal systemic inflammatory response to surgical stimuli often makes early diagnosis of postoperative infections difficult.
Purpose: We investigated whether serum procalcitonin (PCT) levels may be a useful marker of bacterial infections in patients after invasive surgery.
Subjects and methods: The subjects were 40 patients who had undergone radical surgery for esophageal carcinoma by a right thoracoabdominal approach. Nine patients were diagnosed to have a postoperative infection during the first 7 days after surgery. Changes in serum PCT levels were compared between the group diagnosed to have postoperative infection (infection group) and the group without infection (noninfection group).
Results: The postoperative serum PCT levels were significantly higher in the infection group than in the noninfection group (ANOVA: p < 0.01). Serum PCT peaked on postoperative day (POD) 5 in the infection group (8.7 +/- 8.2 ng/ml, mean +/- SD) and on POD 1 in the noninfection group (0.5 +/- 0.5 ng/ml). No significant differences were found between the two groups in leukocyte count, serum CRP or cytokine levels. The receiver operating characteristics (ROC) curve was constructed for infection identification. The area under the ROC curve for peak postoperative PCT was 0.968, and at a cutoff value of 2.0 ng/ml, the sensitivity was 89% and the specificity was 93%.
Conclusions: Serum PCT levels may be useful for the early diagnosis of postoperative infectious complications.