Evaluation of Serum Biomarkers in Predicting the Severity of Community-Acquired Pneumonia: A Prospective Cross-Sectional Observational Study.
DOI:
https://doi.org/10.51168/xpk6xz60Keywords:
Community-acquired pneumonia, Procalcitonin, C-reactive protein, Lactate, Biomarkers, Severity predictionAbstract
Background:
Community-acquired pneumonia (CAP) remains a major cause of morbidity and mortality worldwide. Early identification of severe cases is essential for timely intervention and improved outcomes. Serum biomarkers such as C-reactive protein (CRP), procalcitonin (PCT), neutrophil-to-lymphocyte ratio (NLR), and serum lactate have emerged as valuable tools for assessing disease severity.
Aim:
To evaluate the role of serum biomarkers in predicting the severity of community-acquired pneumonia and their correlation with established clinical severity scores.
Methods:
A prospective observational study was conducted among 100 patients diagnosed with CAP admitted to Madhubani Medical College and Hospital, Madhubani, between April 2025 and January 2026. Serum CRP, procalcitonin, NLR, and lactate levels were measured at admission. Severity was assessed using CURB-65 and Pneumonia Severity Index (PSI) scores. Biomarker levels were compared between severe and non-severe CAP groups.
Results:
Among 100 patients, 62% were males and 38% females. Thirty-five patients had severe CAP. Mean CRP, PCT, NLR, and lactate levels were significantly higher in severe CAP compared to non-severe CAP (p<0.001). Procalcitonin demonstrated the highest predictive accuracy for severe disease (AUC=0.89), followed by lactate (AUC=0.86), CRP (AUC=0.83), and NLR (AUC=0.80).
Conclusion:
Serum biomarkers, particularly procalcitonin and lactate, are valuable predictors of CAP severity and correlate strongly with clinical severity scores. Their incorporation into routine assessment may facilitate early risk stratification and optimize patient management.
Recommendation:
Routine assessment of procalcitonin and serum lactate, alongside conventional severity scores, is recommended for early risk stratification and identification of patients requiring intensive monitoring and aggressive management.
References
1. Karakioulaki M, Stolz D. Biomarkers and clinical scoring systems in community ‑ acquired pneumonia. Ann Thorac Med. 2019;14(December):165‑72. https://doi.org/10.4103/atm.ATM_305_18
2. Seligman R, Ramos-Lima IILF, Vivian III, Sanvicente IIIC, F IIIE, Karoline III, et al. Biomarkers in community-acquired pneumonia : A state-of-the-art review. Clinics. 2012;67(11):1321-5. https://doi.org/10.6061/clinics/2012(11)17
3. Saleh NY, Hassan FM, Omar TA, Gady MF Al, Hussein RSE. Pediatric community-acquired pneumonia : predictive value of heparin-binding protein for severity assessment. Pediatr Res [Internet]. 2026;(October):1-8. Available from: http://dx.doi.org/10.1038/s41390-025-04605-w https://doi.org/10.1038/s41390-025-04605-w
4. Guan C, Chen F, Song Y, Huang Y. A machine learning-based model for assessing community- acquired pneumonia severity using routine blood tests. Front Cell Infect Microbiol. 2026;15(January):1-13. https://doi.org/10.3389/fcimb.2025.1605502
5. Study O, Kim SY, Hong DY, Lee KR, Jung HM, Paik JH. Serum amyloid A as a prognostic biomarker for 30-day mortality in patients with community- acquired pneumonia in the emergency department. Medicine (Baltimore). 2025;104(43):1-6. https://doi.org/10.1097/MD.0000000000045442
6. Gong W, Gao K, Shan Z, Yang L, Fang P, Li C, et al. Research progress of biomarkers in evaluating the severity and prognostic value of severe pneumonia in children. Front Pediatr. 2024;12(October):1-9. https://doi.org/10.3389/fped.2024.1417644
7. Onur B, Bar H, Gulmez A. Role of biomarkers in community-acquired pneumonia management. J Acute Dis. 2024;13(July):87-92. https://doi.org/10.4103/jad.jad_65_24
8. Póvoa P, Coelho L, Cidade JP, Ceccato A. Biomarkers in pulmonary infections : a clinical approach. Ann Intensive Care [Internet]. 2024;14(113):1-15. Available from: https://doi.org/10.1186/s13613-024-01323-0
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Copyright (c) 2026 Dr. Ashutosh Kumar, Dr. Mukesh Kumar, Dr. Ajay Kumar Lal Das
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