Procalcitonin versus C- reactive protein as early markers for postoperative sepsis after major abdominal surgery

Abstract

Infectious complications occur frequently after major abdominal surgery and have a major influence on patient outcome and hospital costs. The early identification of patients who developed infectious complications is crucial for timely and adequate treatment. Severe sepsis is still a major cause of postoperative morbidity and mortality after major surgery, with an incidence ranging between 9 to 12% and high mortality (42% to 80%). Septic complications after major abdominal surgery consist mainly of surgical site infections (up to 40%), pulmonary infections (10%) and urinary infections (5%). Anastomotic leakage and intra-abdominal abscess are the most feared complications and are frequently diagnosed late in the postoperative period since the initial clinical manifestations are very subtle. About 30% of patients admitted to the ICU with intra-abdominal infection died, with mortality rates even higher when peritonitis arises as a complication of a previous operative procedure. The early identification of patients at risk for post-operative infection would be of clinical importance, since clinical signs are usually insensitive and do not allow an early diagnosis. Several biochemical tests are used to identify persistent inflammatory activity in postoperative patients, including CRP, PCT and interleukins. In the present study, 60 patients who underwent elective major abdominal surgery were divided into two groups, 30 patients who developed septic complications (Group Ι, Septic) and 30 patients who had no septic complications (Group Π, Non septic). Hemodynamics, WBCs, CRP, PCT and ABG were measured preoperatively and in 3 postoperative days. We compared and categorized all patients according to Bone criteria for sepsis as studied Bone et al., 1992 in the definition of inflammatory response and sepsis and severe sepsis and septic shock. The current study showed that elevated WBC count was a nonspecific inflammatory marker and one of the SIRS criteria. It failed to allow immediate diagnosis and prognosis because of the time taken to produce a reaction and the duration of increased counts. CRP level on the third postoperative day was a good predictor of postoperative sepsis. CRP concentrations have failed to allow immediate diagnosis and prognosis because of the time taken to produce a reaction and the duration of increased serum concentrations; thus, CRP could not be used as an early marker for postoperative sepsis. PCT was more specific for sepsis induced inflammation than CRP septic complications. The current study suggested that PCT measurements might be useful for early diagnosis of septic postoperative complications. A PCT level > 1.1ng/ml associated with SIRS on first postoperative day could allow early diagnosis of postoperative sepsis after major abdominal surgery. In conclusion, PCT is a good early diagnostic marker and is superior to CRP and WBCs in early detection of postoperative sepsis after major abdominal operations. The study recommends the use of PCT in the 1st postoperative day after major abdominal operations to early detect postoperative sepsis and enhance early interference to prevent it.