Evaluation of Serum Inflammatory Biomarkers in Ventilator Associated Pneumonia: A Study from Tertiary Care Hospitals in Islamabad, Pakistan

Abstract

Background: Ventilator-associated Pneumonia (VAP) is one of the most common infection in critically ill patients receiving mechanical ventilation. It remains a major cause of increased mortality among these patients and contributes to prolonged hospital stay. Early diagnosis of VAP is often difficult because commonly used clinical and laboratory findings can also appear in other respiratory conditions and lack specificity. Serum inflammatory biomarkers such as Pro-calcitonin (PCT), C-reactive Protein (CRP) and White Blood Cells (WBCs) Count may improve diagnostic accuracy and help monitor the disease progression. Methodology: This study included 70 mechanically ventilated ICU patients diagnosed with VAP across the selected Tertiary Care Hospitals of Islamabad. Levels of PCT, CRP and WBCs were measured across three different points of time; during first 48 hours of mechanical ventilation (base-line value), at clinical suspicion of VAP and one week after the diagnosis of VAP. SPSS version 27 was used for the statistical analysis of data. A p value of less than 0.05 was considered significant. Results: Serum PCT levels showed a significant rise from base-line value to the time of VAP suspicion and then a significant fall one week after VAP diagnosis (p < 0.001). CRP levels also increased at the time of suspicion and then decreased one week after diagnosis but the overall variation in its levels was not statistically significant (p = 0.116). WBCs Count only showed minimum fluctuation across the three time points without any statistically significant difference (p = 0.108). Conclusion: Among the evaluated biomarkers, PCT demonstrated greater diagnostic utility as compared to CRP and WBCs Count. Its dynamic changes closely reflected disease’s onset, progression and its response to treatment. These findings suggest that PCT is a more reliable biomarker for VAP than CRP and WBCs Count. These findings suggest the use of PCT as a clinical adjunct for the diagnosis and monitoring of VAP.