Acute phase reactants in non-COVID-19 community-acquired pneumonia

Abstract Background Acute phase reactants (APR) are markers of inflammation that could be applied for the assessment of community-acquired pneumonia (CAP) severity in association with various pneumonia severity scores. So, the aim of the study was to assess levels of APR such as total leucocytic count (TLC), platelets, neutrophils, neutrophils-to-lymphocyte ratio (NLR), CRP, D-dimer, ferritin, and ESR in patients with CAP and to correlate between their values and disease severity. Methodology The study included 51 patients diagnosed as non-COVID-19 (CAP). Patients were classified into two groups group A (pneumonia only) and group B (pneumonia complicated with empyema/complicated para-pneumonic effusion). All patients underwent clinical evaluation, CURB65, radiological assessment, and blood sampling to measure APR. Results The mean age of patients was 47 ± 17 years. The main symptoms were productive cough (90.2%) and Fever (92.2%).TLC, platelets, neutrophils, CRP, D-dimer, ferritin, and ESR were elevated than normal values. Significant positive correlations were found between the duration of fever and CRP, D-dimer, and ferritin with p values = 0.024, 0.012, and 0.034 respectively. Significant positive correlations were found between CURB65 and both CRP and ferritin with p values = 0.007 and 0.020. A significant increase in platelet count and ESR values was found in group B than in group A. Conclusion APR are important markers that can be used in the assessment of CAP in collaboration with clinical evaluation and severity scores. CRP, D-dimer, and ferritin were positively correlated with CURB65, while ESR and platelets could be considered predictors of the development of complications. Trial registration Retrospectively registered, registration number NCT05926089 , date of registration is 06/29/2023.