Objective To evaluate the role of procalcitonin (PCT) and high sensitivity C-reactive protein (hs-CRP) in the diagno. sis of pulmonary infection in a cohort of patients over 65 years of age with multiple respiratory symptoms. Methods With a retrospective cohort study design, all multimorbid patients ≥65 years-old with acute respiratory symptoms admitted to our hospital from August 2016 to August 2017 were evaluated. Pulmonary infection diagnosis, comorbidities expressed through Cumulative Illness Rating Scale (CIRS), setting of living, length of stay, serum hs-CRP and PCT at admission were collected for each patient. Data were analyzed with Mann-Whitney's U test and multivariate Cox logistic regression analysis. A Receiver Operating Characteristic (ROC) curve was used to verify each biomarker's association with pneumonia diagnosis. Results Compared with patients without pulmonary infection, the levels of serum hs-CRP, PCT and hospital stay in patients with pulmonary infection were significantly increased (P < 0.05). The best statistical cut-off values for detection of pulmonary infection were as follows: PCT concentration was 0.26 ng/mL (sensitivity 69.1%, specificity was 85.3%), hs-CRP was 61 mg/L (sensitivity 84%, specificity 75.5%) and WBC was 11 470 mm3 (sensitivity 84.9%, specificity was 47.4%);Combined detection of PCT > 0.26 ng/mL and Hs-CRP > 61 mg/L could be used to improve sensitivity (92%) and specificity (90.3%). The multivariate Cox regression model analysis showed that the risk of pulmonary infection of hs-CRP >61 mg/L increased by 3.59 times at admission (OR 3.59, 95%CI: 2.35-5.48, P <0.001) and PCT>0.26 ng/mL increased by 2.81 times (OR 2.81, 95%CI: 2.14- 4.87, P <0.001). Conclusion Both PCT and hs-CRP are valuable markers in predicting pulmonary infection in elderly patients with multiple diseases, and the combined detection of them may help to improve the diagnostic value.
Hospital and Medicine
High sensitivity C- reactive protein