Serum Procalcitonin, Interleukin-6 and Lactate In Critically-ill Children With Systemic Inflammatory Response Syndrome

1Mohamed I Abdel–Hamid, 1Ahmed M. Amin, 2Mostafa Abo–Farrag, 2Hamid El – Sharkawy, 2Amr Zoair, 2Ahmed Abdel Razik

1Microbiology and 2Pediatric Departments, Faculty of Medicine, Tanta University, Tanta, Egypt.

The study was designed to validate the usefulness of admission serum procalcitonin (PCT), as an early reliable diagnostic marker of sepsis in critically-ill children with systemic inflammatory response syndrome (SIRS) in comparison with pro-inflammatory cytokine interleukin-6 (IL-6), serum lactate, total leucocytic count (TLC), and C-reactive proteins (CRP). The study is a prospective observational study. From Pediatric intensive care unit of Tanta University Hospital. A total of 59 children with SIRS, having a median age of 61.3 months. They included 37 males and 22 females. Children who had received antibiotics for > 24 hrs were excluded. A total of 19 patients (32.2%) had non-infectious SIRS and 40 patients (67.8%) had infectious SIRS. Patients with infectious SIRS were subdivided into three groups according to the severity of sepsis; uncomplicated sepsis (n = 10); sepsis syndrome (n=21) and septic shock (n=9). The admission pediatric risk of mortality (PRISM) score, admission multiple organ system failure (MOSF) score, and ultimate outcome were recorded. Serum PCT, serum IL-6, serum lactate, TLC, CRP were measured at admission to the intensive care unit for all patients. Second day laboratory data were obtained for patients who experienced severe SIRS by day 2 (36 patients). The observed mortality was 10/59 (17%). The admission PCT was shown to be the most reliable marker for the early differentiation of infectious vs. non-infectious SIRS (P<0.05), whereas admission IL-6, lactate, TLC, and C-RP were shown to be insignificant markers for early differentiation of infectious vs. non-infectious SIRS (P>0.05). Furthermore, higher admission serum concentrations of PCT correlated significantly with sepsis severity (P<0.05) but insignificantly associated with non-survival (P>0.05). On the other hand, persistent elevation of PCT level despite 24 hrs of ongoing antibiotic therapy and intensive care was found to be significantly associated with increased mortality (P<0.001). In conclusion: i) Admission PCT is suggested to be a reliable indicator of sepsis in critically-ill children with SIRS. ii) serial PCT assay might be of value in predicting the outcome and in monitoring the response to treatment in children with severe infectious SIRS. iii) The current data add to a growing body of evidence that PCT release may be harmful in critically ill children with sepsis. These data highlight the great need to develop “anti-PCT” therapies that might prove more efficacious than other anti-cytokine treatment modalities in such children.