Clinical Utility of Multiplex PCR for Managing Community-Acquired Pneumonia in Diabetic and Non-Diabetic Patients

To compare the positivity rates of pathogens detected in diabetic and non-diabetic pneumonia cases, to assess the role of multiplex respiratory polymerase chain reaction (PCR) testing in diagnosis, and to compare inflammatory parameters between the two groups.

Observational study. Place and Duration of the Study: Department of Pulmonology, Hisar Intercontinental Hospital, Istanbul, Turkiye, from September 2021 to June 2023.

The study included 151 adults diagnosed with community-acquired pneumonia (CAP). Group 1 comprised patients with diabetes (n = 42), and Group 2 consisted of patients without diabetes (n = 109). Patients' demographic and clinical data were collected and statistically compared using the Mann-Whitney U test, the median test, and the Chi-square Independence test.

The positivity rate of the multiplex respiratory PCR test was significantly greater in Group 1 compared with Group 2 (p = 0.005). In Group 1, the most frequently identified nasopharyngeal pathogen was SARS-CoV-2. In Group 2, Streptococcus pneumoniae was the predominant pathogen. Procalcitonin (PCT), C-reactive protein (CRP), and neutrophil levels, as well as the CRP-to-lymphocyte ratio (CLR), were markedly higher in Group 1 compared with Group 2 (p = 0.016, p = 0.002, p = 0.016, and p = 0.016, respectively).

A significantly higher PCR test positivity rate was found in diabetic patients compared with non-diabetic. Differences in the distribution of specific pathogens between the groups were observed. In addition, this study confirmed that diabetic pneumonia cases exhibit elevated levels of inflammatory biomarkers.

Pneumonia, Diabetes, Multiplex respiratory polymerase chain reaction test.