TY - JOUR T1 - Procalcitonin kinetics and nosocomial pneumonia in older patients JF - Respiratory Care DO - 10.4187/respcare.02364 SP - respcare.02364 AU - Yan Shi AU - Ying-chun Xu AU - Xi Rui AU - Hong-min Zhang AU - Yao Wang AU - Wei Du Y1 - 2013/12/10 UR - http://rc.rcjournal.com/content/early/2013/12/03/respcare.02364.abstract N2 - Background Early identification of treatment failure (TF) of nosocomial pneumonia (NP) remains a major challenge. To test whether use of procalcitonin (PCT) kinetics could assess the clinical efficacy in older critically ill patients with NP. Methods A prospective observational study was conducted in 60 patients (≥65 years) admitted to the intensive care unit with severe NP. Serum PCT was measured on day 0, day 3, day 7 and at the end of treatment (EOT). The PCT time course was analyzed according to the therapeutic efficacy. Results PCT were elevated in all patients (n=60) on day 0 and the median levels (range) were 2.5 ( 0.85–42.7) μg/L. There were no differences between the improvement patients (n=41) and those without improvement ( n=19) in PCT on day 0 ( p>0.05). However, lower PCT on days 3, 7 and at the EOT (all p<0.05) as well as greater rate of PCT decline between day 0 and day 3( ΔPCTD3% ) (29.5 ± 10.8% vs 15.1 ± 5.9%, p = 0.009) were found in the improvement patients than in those without improvement. ΔPCTD3% was the best single predictor of efficacy (area under the curve [AUC], 0.791, p < 0.001) and had a sensitivity of 75.7% and a specificity of 72.0% with threshold of 26.2%. By comparison, traditional parameters and absolute PCT failed to predict treatment response ( p>0.05). Indeed, the combination of ΔPCTD3% > 26.2% and modified clinical pulmonary infection score (mCPIS) < 6 points could improve the predictive value (AUC, 0.890; sensitivity, 81.3%; specificity, 86.5% ). Conclusions PCT levels were not influenced by aging and PCT kinetics might help to identify TF. ΔPCTD3% combined with CPIS have been shown to be an marker of clinical efficacy at an earlier stage. ER -