C-reactive Protein (CRP) and Procalcitonin (PCT) Combined Testing in the Diagnosis of Elderly Patients with Bacterial Pneumonia

Abstract

Objective: To analyze the diagnostic value of combined testing of C-reactive protein (CRP) and procalcitonin (PCT) in elderly patients with bacterial pneumonia. Methods: This study included 50 elderly patients with bacterial pneumonia as the observation group and 50 patients with non-bacterial pneumonia as the control group, recruited from May 2022 to October 2023. Fasting venous blood samples were collected in the morning from all 100 participants. CRP levels were measured using a fully automated biochemical analyzer, while PCT levels were detected using the immunoturbidimetric luminescence method. Results: CRP and PCT levels were significantly higher in bacterial pneumonia patients [(98.25 ± 11.59) mg/L and (3.57 ± 1.35) μg/L, respectively] compared to the control group [(5.55 ± 2.78) mg/L and (0.25 ± 0.12) μg/L, respectively], with significant intergroup differences (P < 0.05). Patients with severe bacterial pneumonia exhibited higher serum CRP and PCT levels compared to those with moderate or mild disease (P < 0.05). The combined testing of CRP and PCT showed higher sensitivity and specificity than individual tests. In the observation group, CRP and PCT levels significantly decreased after treatment compared to pre-treatment levels. Conclusion: The combination of CRP and PCT testing provides high diagnostic accuracy for bacterial pneumonia in elderly patients. It effectively differentiates bacterial from non-bacterial infections, offering valuable data to guide clinical treatment.