(605) Procalcitonin and Clinical Outcomes in Community-Acquired Pneumonia at Risk of Resistant Organisms

Introduction: Community-acquired pneumonia (CAP) is a leading global infectious cause of death. Despite existing scoring systems, accurately assessing CAP severity and predicting outcomes remains challenging. C-reactive protein (CRP) and procalcitonin (PCT) are biomarkers often used to predict inflammatory states, but their efficacy in general populations varies

Methods: This retrospective study included Bridgeport Hospital patients (01/01/2015-12/31/2019) with CAP diagnosis based on ICD-10 codes, prior Pseudomonas or MRSA infection, nursing home stay, recent admission, or IV antibiotic use in last 90 days. Patients with renal disease or immunosuppression of any type were excluded. Multivariable logistic regression assessed the association between admission procalcitonin and outcomes. A receiver operating characteristic (ROC) curve determined the optimal procalcitonin threshold.

Results: Between 2015 and 2019, a total of 527 patients were identified. Among these the mean age was 62, mortality 6.5%, 75% were medical floor patients and 44% had severe comorbidities. Procalcitonin was significantly associated with in-hospital mortality (OR 1.063, CI 1.028-1.124) after adjustment. No association was found with mechanical ventilation, vasopressors, or acute kidney injury. The Receiving operating characteristic curve identified 0.1550 as the optimal procalcitonin threshold.

Conclusions: Procalcitonin is associated with in-hospital mortality in CAP patients at risk for multidrug-resistant organisms. These findings suggest procalcitonin's potential as a component of a predictive model rather than a standalone predictor.