The usefulness of serum procalcitonin, C-reactive protein, soluble triggering receptor expressed on myeloid cells 1 and Clinical Pulmonary Infection Score for evaluation of severity and prognosis of community-acquired pneumonia in elderly patients.

AIMS: To comparatively analyze the usefulness of serum procalcitonin (PCT), C-reactive protein (CRP), soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) and Clinical Pulmonary Infection Score (CPIS) for assessing the severity and prognosis of community-acquired pneumonia (CAP) in the elderly.

METHODS: A total of 214 elderly patients with CAP and 106 healthy persons were enrolled in this prospective study. On the admission day, serum inflammatory markers, including CRP, PCT, sTREM-1, and CPIS were analyzed. By severity, the CAP patients were subdivided into non-severe CAP group and severe CAP group. By outcome, the patients were classified into survival group and death group. The efficiency of three inflammatory markers and CPIS on predicting prognosis of pneumonia patients was then analyzed.

RESULTS: The serum inflammatory markers and CPIS were significantly higher in CAP patients than in healthy controls. These biomarkers and CPIS were significantly higher in patients with severe CAP than in patients with non-severe CAP. Compared with patients who would survive, these markers and CPIS were significantly higher in patients who would die. Receiver operating characteristic curve analysis showed that the area under the curve and sensitivity were higher for serum sTREM-1 than for other indicators, while the specificity of serum PCT was the highest.

CONCLUSIONS: Serum CRP, PCT, and sTREM-1 and CPIS determined on the admission day are effective indicators to evaluate the severity and prognosis of CAP in the elderly. The prognostic value of PCT and sTREM-1 is better than that of CRP and CPIS.