Procalcitonin versus C-reactive protein: Usefulness as biomarker of sepsis in ICU patient

BACKGROUND: Early diagnosis and appropriate therapy of sepsis is a daily challenge in intensive care units (ICUs) despite the advances in critical care medicine. Procalcitonin (PCT); an innovative laboratory marker, has been recently proven valuable worldwide in this regard. OBJECTIVES: This study was undertaken to evaluate the utility of PCT in a resource constrained country like ours when compared to the traditional inflammatory markers like C - reactive protein (CRP) to introduce PCT as a routine biochemical tool in regional hospitals. MATERIALS AND METHODS: PCT and CRP were simultaneously measured and compared in 73 medico-surgical ICU patients according to the American College of Chest Physicians (ACCP) criteria based study groups. RESULTS: The clinical presentation of 75% cases revealed a range of systemic inflammatory responses (SIRS). The diagnostic accuracy of PCT was higher (75%) with greater specificity (72%), sensitivity (76%), positive and negative predictive values (89% and 50%), positive likelihood ratio (2.75) as well as the smaller negative likelihood ratio (0.33). Both serum PCT and CRP values in cases with sepsis, severe sepsis and septic shock were significantly higher from that of the cases with SIRS and no SIRS (P < 0.01). CONCLUSION: PCT is found to be superior to CRP in terms of accuracy in identification and to assess the severity of sepsis even though both markers cannot be used in differentiating infectious from noninfectious clinical syndrome.