Pneumonia is defined as an infection of the pulmonary parenchyma. Despite being the cause of significant complications and deaths, pneumonia is often wrongly diagnosed, mistreated, and underestimated. The incidence rates are highest in old-aged patients. In the current prospective observational study, we intend to study the utility of procalcitonin (PCT) level and serum C-reactive protein (CRP) level for diagnosing pneumonia.

Prospective observational studies.

The study was conducted in RajaRajeswari Medical College and Hospital, Bengaluru, during the period extending from June to May 2014. Eighty patients, aged more than 18 years, with diagnosis of pneumonia were included in the study. Serum PCT levels were calculated using BRAHMS PCT Kryptor immunofluorescent assay (Biomerieux, France). Other routine investigations, including CRP, sputum culture, and endotracheal secretions cultures, were done. Chisquare analysis was done to assess its prognostic and diagnostic significance. Data were analysed with Statistical Package for the Social Sciences (version 17.0 for Windows).

C-reactive protein was positive in 60 (75%) of the patients, and PCT was positive in 45 (56.25%) patients; 28 patients had PCT levels 0.5 to 1.5 ng/mL, 1 (3.6%) had CRP <6 mg/mL, 27 (96.4%) had CRP >6 mg/mL; 17 patients had PCT values >1.5 ng/mL and CRP was positive in all patients (p < 0.001). Streptococcus pneumonia was the most common and isolated in 8 (10%) patients. C-reactive protein is a useful and better adjuvant in the diagnosis of community-acquired pneumonia (CAP). Positive PCT levels indicate a bacterial etiology for pneumonia. A high PCT level is a poor prognostic indicator and is associated with a higher mortality.

Prajwal KC, Krishna MV, Patil S. Study of Clinical Profile of Community-acquired Pneumonia with Special Reference to C-reactive Protein and Procalcitonin Levels. J Med Sci 2016;2(2):27-30.