G83 PROCALCITONIN VERSUS C-REACTIVE PROTEIN AND IMMATURE-TO-TOTAL NEUTROPHIL RATIO AS MARKERS OF INFECTION AFTER CARDIOPULMONARY BYPASS IN CHILDREN

D. Y. Park, P. McMaster.University Hospital of North Staffordshire, Stoke-on-Trent, UK

Objective: This report is composed of two studies. In the first study, plasma concentrations of procalcitonin (PCT), C-reactive protein (CRP) and of immature-to-total neutrophil ratio (ITR) were measured after cardiac surgery to analyse postoperative induction of PCT. The aim of second study is then to test the hypothesis that PCT is a more reliable marker of infection than CRP or ITR in the post cardiopulmonary bypass (CPB) child.

Methods: PCT, ITR, and CRP were measured serially in 283 post CPB children on the first, second, third, and fifth postoperative day. When a post CPB patient is suspected or proven to have an infection, the researchers in PICU will approach the family for written consent to retrieve any remaining blood and serum from haematology and biochemistry (the laboratories retain any unused specimen for seven days following collection). Overall 65 infected children out of 283 were included into the second study in this way. Results of other investigations suggestive of infection and clinical impression (for example, wound infection) were also recorded.

Results: 218 post CPB children with no signs of infection were included in the first study. PCT levels remained fairly low postoperatively. PCT was not significantly different between children without any signs of infection and the ones with local infection. However, they were raised significantly in patients with signs of sepsis or definite sepsis. CRP increased in all subgroups of children studied, even in those without signs of infection. In definite sepsis CRP was increased more than the other subgroups. ITR remained high from the start and gradually decreased as the day goes by, except in definite sepsis; where they remained high. In a receiver operating characteristic (ROC) curve analysis, PCT were found to be the most reliable laboratory …