This study aimed to assess the utility of estimation of plasma Procalcitonin (PCT) and
serum interleukin-6 (IL-6) and C-reactive protein (CRP), as early (within 24 h after
surgery) predictors of postoperative septic complications in patients who underwent
elective colonic resection for malignant disease. The study included 40 patients and
10 healthy subjects as controls for the preoperative values. Patients were observed at
ICU for their first 5 postoperative days for the development of systemic inflammatory
response syndrome (SIRS), sepsis, severe sepsis or septic shock that were defined
according to Bone's criteria. Patients were allocated into 3 groups on the basis of
signs of sepsis: Group A (No SIRS/Sepsis), Group B (SIRS) and Group C (Sepsis)
group. Blood samples were obtained the day before surgery (Day-0) and at the
morning of the first postoperative day (Day-1) for estimation of serum CRP and IL-6
and plasma PCT. Eight patients developed SIRS and 9 patients progressed to sepsis
with a total morbidity rate of 42.5%. One patient developed septic shock and died
with a mortality rate of 2.5%. Day-0 serum CRP and plasma PCT showed nonsignificant
difference, while Day-0 serum IL-6 was significantly higher compared to
control levels. However, Day-1 levels of the three parameters were significantly
higher compared to their Day-0 levels. Day-1 serum levels of CRP showed nonsignificant
difference between the three study groups; however, Day-1 serum IL-6
was non-significantly higher in group B but was significantly higher in group C
compared to its levels in group A with a non-significant increase in group C
compared to group B . Day-1 plasma levels of PCT were significantly higher in
groups B and C compared to its levels in group A with a significant increase in group
C compared to group B. There was a positive significant correlation between the
frequency of occurrence of SIRS and/or septic complication with levels of serum IL-6
and of plasma PCT, while the correlation was positive non-significant with serum
CRP levels and ROC curve analysis showed that plasma PCT levels were highly
specific (AUC=0.928), followed by serum levels of IL-6 (AUC=0.763) and serum
CRP was the least specific parameter (AUC=0.498). It could be concluded that PCT
can be used as a reliable diagnostic parameter to detect and to monitor infectious
complications in the postoperative period after colonic surgery and can be detected
before the occurrence of clinical infection, especially in patients suspected to be at
higher risk for development of SIRS or septic complications.