[Procalcitonin and C-reactive protein as early indicators of postoperative intra-abdominal infection after surgery for gastrointestinal cancer].

AIM to evaluate the association between serum levels of procalcitonin and C-reactive protein, on the first 3 postoperative days, and the appearance of postoperative intra-abdominal infection. METHOD Prospective observational study including 67 patients operated on for colo-rectal, gastric and pancreatic cancer. Serum levels of procalcitonin and C-reactive protein were analyzed before surgery and daily until the third postoperative day. Values of procalcitonin (PCT) and C-reactive protein (CRP) were recorded as well as their accuracy for detection of postoperative intra-abdominal infection (PIAI). RESULTS The incidence of postoperative intra-abdominal infection was 13.4%. CRP serum levels at 72h, PCT serum levels at 24, 48 and 72h and the ratio between serum levels of CRP at 72hours and serum levels of CRP at 48hours (CRP D3/CRP D2) were significantly associated with the appearance of postoperative intra-abdominal infection. The highest sensitivity corresponded to PCT at 72hours (88.9%); the highest specificity and positive predictive value corresponded to the ratio CRP D3/CRP D2 (96.49% and 71.4%, respectively); the highest negative predictive value to procalcitonin at 72h and 24h. CONCLUSIONS Serum levels of PCT are significantly associated with the appearance of postoperative intra-abdominal infection. Sensitivity and predictive positive values are low, but negative predictive value is high, even at 24h after surgery.