Retrospective observational study of procalcitonin in oriental intensive care unit patients with suspected nosocomial infection

Abstract

Introduction Procalcitonin (PCT) was one of the recently described bio-markers in rapid diagnosis of severe sepsis. However, the reported sensitivity and specificity of PCT varied among studies and the results of Oriental population was scanty. The objective of this study was to determine the usefulness of serum procalcitonin level of the Oriental intensive care unit patients in diagnosis of nosocomial infection Materials and methods This was a retrospective observational single-arm cohort review study, which was conducted in a mixed medico-surgical Intensive Care Unit (ICU) of a regional public hospital (United Christian Hospital) in Hong Kong SAR, China between 1st January, 2009 and 30th June, 2009, to determine the blood procalcitonin level at early diagnosis (and differentiation) in patients with SIRS and hospital-acquired sepsis, in comparison with other parameters and markers. Results Total 33 patients were recruited in this study. The mean age was 61 years old with nearly 1:1 male to female ratio. The commonest offending organism and involved system in nosocomial sepsis in ICU in this cohort was Gram negative micro-organisms and respiratory tract respectively. The positive likelihood ratios (LR) of nosocomial sepsis in ICU were 4.242 (P = 0.032), 5.711 (P = 0.016) and 8.550 (P = 0.023) with PCT > 0.1 ng/ml, PCT > 0.5 ng/ml and PCT > 5 ng/ml respectively. Good discriminative power of PCT as a test in diagnosing severe sepsis and septicaemia in ICU (AUC of ROC-curve 0.78-0.90) was also demonstrated. In patients with severe sepsis, at serum PCT cut-off point 1.23 ng/ml, the sensitivity and specificity was 89.5% and 71.4% respectively. Conclusion Our study demonstrated the consistent usefulness of PCT, including in diagnosis of severe nosocomial sepsis and septicaemia in oriental ICU patients.