Assessment of Inflammatory Biomarkers as Predictors of Disease Severity in Patients with Acute Respiratory Infections

Authors

  • Oluwatobi Ifeoma Lawal Clinical Research Scientist, Russia. Author

Keywords:

Inflammatory biomarkers, Acute respiratory infections, IL-6, Procalcitonin, C-reactive protein, Disease severity, Predictive modeling

Abstract

Purpose: This study investigates the prognostic value of key inflammatory biomarkers in determining disease severity among patients diagnosed with acute respiratory infections (ARIs). By evaluating a panel of routinely measured biomarkers, we aim to identify early indicators of clinical deterioration and improve risk stratification at admission.

Methodology: A prospective cohort design was employed in a tertiary care setting. Clinical data and blood samples from 312 patients presenting with ARIs were collected upon hospital admission. The biomarkers examined included C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT), ferritin, and neutrophil-to-lymphocyte ratio (NLR). Statistical associations between biomarker levels and disease outcomes—such as ICU admission, oxygen requirement, and 28-day mortality—were analyzed using multivariable logistic regression and receiver operating characteristic (ROC) curves.

Findings: Elevated levels of IL-6, PCT, and CRP showed strong correlations with clinical severity, particularly in predicting ICU admission and oxygen requirement. IL-6 demonstrated the highest predictive accuracy (AUC: 0.87), followed by PCT and CRP. Ferritin and NLR were moderately predictive. These biomarkers may thus serve as early warning indicators, supporting more timely and targeted interventions.

Practical implications: Incorporating these biomarkers into standard clinical triage algorithms could enhance early detection of high-risk ARI patients. This would enable clinicians to allocate critical care resources more effectively, particularly in resource-constrained environments.

Originality: This study extends knowledge by simultaneously evaluating multiple biomarkers in a real-world clinical population using robust multivariate modeling. The integrated analysis underscores the clinical utility of combining inflammatory markers for better predictive performance.

References

[1] Pepys, Mark B., and Gideon M. Hirschfield. "C-reactive protein: a critical update." The Journal of Clinical Investigation, vol. 111, no. 12, 2003, pp. 1805–1812.

[2] Tanaka, Toshio, Masashi Narazaki, and Tadamitsu Kishimoto. "IL-6 in inflammation, immunity, and disease." Cold Spring Harbor Perspectives in Biology, vol. 6, no. 10, 2014, a016295.

[3] Schuetz, Philipp, Mirjam Christ-Crain, and Beat Müller. "Procalcitonin and other biomarkers to improve assessment and antibiotic stewardship in infections – hope or hype?" Swiss Medical Weekly, vol. 141, 2011, w13259.

[4] Liu, Yingxia, et al. "Neutrophil-to-lymphocyte ratio as an independent risk factor for mortality in hospitalized patients with COVID-19." Journal of Infection, vol. 81, no. 1, 2020, pp. e6–e12.

[5] Lippi, Giuseppe, and Mario Plebani. "Procalcitonin in patients with severe coronavirus disease 2019 (COVID-19): A meta-analysis." Clinica Chimica Acta, vol. 505, 2020, pp. 190–191.

[6] Herold, Tobias, et al. "Elevated levels of IL-6 and CRP predict the need for mechanical ventilation in COVID-19." Journal of Allergy and Clinical Immunology, vol. 146, no. 1, 2020, pp. 128–136.e4.

[7] Henry, Brandon M., et al. "Hematologic, biochemical and immune biomarker abnormalities associated with severe illness and mortality in COVID-19: a meta-analysis." Clinical Chemistry and Laboratory Medicine, vol. 58, no. 7, 2020, pp. 1021–1028.

[8] Mehta, Puja, et al. "COVID-19: consider cytokine storm syndromes and immunosuppression." The Lancet, vol. 395, no. 10229, 2020, pp. 1033–1034.

[9] Han, Huan, et al. "Prominent changes in blood coagulation of patients with SARS-CoV-2 infection." Clinical Chemistry and Laboratory Medicine, vol. 58, no. 7, 2020, pp. 1116–1120.

[10] Huang, Chaolin, et al. "Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China." The Lancet, vol. 395, no. 10223, 2020, pp. 497–506.

[11] Zhao, Kun, et al. "Neutrophil-to-lymphocyte ratio as a biomarker in severe COVID-19 patients: a retrospective cohort study." The International Journal of Laboratory Hematology, vol. 42, no. 6, 2020, pp. 756–762.

[12] Zhou, Fei, et al. "Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study." The Lancet, vol. 395, no. 10229, 2020, pp. 1054–1062.

Downloads

Published

2026-01-08

How to Cite

Assessment of Inflammatory Biomarkers as Predictors of Disease Severity in Patients with Acute Respiratory Infections. (2026). ICMERD-International Journal of Medical Science (ICMERD-IJMS), 7(1), 1–7. https://icmerd.org/index.php/ICMERD-IJMS/article/view/ICMERD-IJMS_07_01_001