Clinical significance of procalcitonin and C-reactive protein in acute exacerbations of chronic obstructive pulmonary disease: A retrospective study
Introduction: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are a common cause of hospitalization, while the empirical use of antibiotics increases the need for reliable biomarkers. The aim of this study was to evaluate the diagnostic and prognostic value of procalcitonin (PCT) and C-reactive protein (CRP) in bacterial exacerbations. Methods: This retrospective study included 50 patients hospitalized due to AECOPD during the period from August to December 2025. PCT and CRP levels, as well as clinical outcomes including the need for mechanical ventilation and mortality, were analyzed. Results: Bacterial etiology was confirmed in 82% of patients, with significantly higher PCT and CRP levels (p < 0.001). PCT ≥ 0.25 ng/mL was associated with a greater need for NIV (35.3% vs. 6.1%; p = 0.013) and a trend toward higher mortality. ROC analysis demonstrated better prognostic value of PCT for in-hospital mortality (AUC 0.80) compared to CRP (AUC 0.75). Discussion: PCT and CRP play an important role in the triage of patients with AECOPD. CRP demonstrates good sensitivity, whereas PCT is a more specific marker of bacterial infection and a more accurate prognostic indicator. Conclusion: Procalcitonin and CRP are useful biomarkers in the evaluation of AECOPD, with PCT showing greater specificity and better prognostic value.