Прокальцитонин как предиктор бактериемии в послеоперационном периоде у кардиохирургических больных

Purpose of the study: To define diagnostics ability of procalcitonin (PCT) test for prediction of bacteremia of different etiology in cardio-surgical patients. Materials and methods: 10158 pairs of blood examples from cardio-surgical patients in early postoperative period were studiedfrom 2007 to 2012. Results of PCT test were compared with blood cultures. The data is presented as absolute values and proportions. Furthermore a mean and standard error of the mean is presented. Differences in compared groups with p<0.05 are considered statistically significant. Results: In average a bacteremia occurred on a 6th day of postoperative period. Frequency of the positive blood cultures was 20.7%. 972 cases of bacteremia (46.2%) was caused by Gram-positive cocci, 702 cases (33.3%) by Gram-negative bacteria and 338 (16.1%) by yeast-like fungi. Mixt-cultures were defined in 93 cases (4.4%). Monocultural bacteremia was analyzed only (n=2012). Average level of РСТ was higher (statistically significant) in cases with blood cultures than in cases without it (14.35±0.91 ng per ml vs. 7.35±0.26 ng per ml, р=0). The highest РСТ was fixed in cases of bacteremia caused by Gram-negative bacteria (26.03±2.13 ng per ml). There was no significant difference between bacteremia due to enterobacteria and non-fermenting agents (30.56±4,05 ng per ml и 22.79±0.21 ng per ml, р=0.07). Statistically significant differences according to the average РСТ were defined between bacteremia caused by Gram-negative bacteria (26.03±2.13 ng per ml), Gram-positive cocci (7.24±0.88 ng per ml, р=0), Candida species (9.02±1.84 ng per ml, р=0), and cases of contamination (9.92±2.79 ng per ml, р=0). Average РСТ was not significantly different in cases of bacteremia due to coagulase-negative staphylococci (5.94±0.87 ng per ml), S. aureus (4.04±0.9 ng per ml), enterococci (15.72±3.52 ng per ml), Candida species (9.02±1.84 ng per ml), in cases of contamination (9.92±2.79 ng per ml) and in cases of the negative blood cultures (7.35±0.26 ng per ml). According to ROC-analysis the optimal cut-offpoint for РСТ as a predictor of Gram-negative bacteremia was 2.47 ng per ml, AUC 0.7 (95%DI 0.68-0.72). Index of sensitivity was 64%. Conclusions: РСТ level in blood plasma ofpatients with bacteremia higher (statistically significant) than in patients with negative blood cultures. Gram-negative infection is more likely in cases when РСТ higher than 2.47 ng per ml.