Procalcitonin Versus C-Reactive Protein at Different SOFA Scores in I.C.U. Sepsis: Diagnostic Value and Therapeutic Implications

Introduction: Procalcitonin is a pro-hormone of calcium homeostasis released by many tissues during infection and is probably a part of abnormal systemic response that leads to severe sepsis. CRP produced by hepatocytes, predominantly under control of cytokine IL-6, may provide an early indication of developing SIRS with progression to sepsis that is more sensitive than the standard clinical criteria of infection. Objective: To compare the impact of PCT and CRP in the diagnosis and prognosis of sepsis at different SOFA scores. Methods: A prospective study conducted on 25 patients divided into group I, (14 patients) who were diagnosed as SIRS, sepsis, severe sepsis or septic shock with organ affection; and group II, (11 patients) diagnosed as SIRS and sepsis but without organ affection. APACHE II score on admission and SOFA score every day were applied. Procalcitonin was measured by in-vitro ELISA technique and CRP by rapid latex agglutination test on 1st, 5^th and on discharge or day of death. Ten healthy individuals served as controls. Results: Septic patients had statistically significant high PCT CRP levels (6.349±4.95 vs. 0.299±0.184ng/ml; p 0.001 and 28.36±16.342 vs. 12±6.914mg/l; p=0.003); however; PCT was significantly higher in group I than in group II (8.09±4.04 vs. 0.320±0.132ng/ml; p 0.005), while CRP was not (36± 13.856 vs. 41.45±23.61ng/ml; p=0.677). Moreover; there were a statistically significant difference in PCT levels between survivors (18pts.) and non-survivors (7pts.) on 1st day (3.317± 3.978 vs. 9.740±4.847ng/ml; p=0.002), 5^th day (0.7858±0.907 vs. 10.608±4.592; p=0.001) and on discharge or the day of death (0.2951±0.195 vs. 15.920±2.769; p 0.0001) while there were no differences in CRP between survivors and non-survivors. Conclusion: PCT is prognostically superior to CRP for its strong correlation with mortality significant correlation to both SOFA and APACHE II scores. PCT plays a diagnostic as well as prognostic role in systemic sepsis, while CRP had a diagnostic role only but does not serve as a prognostic marker in sepsis.