Diagnostic Performance & Prognostic Significance of Procalcitonin & C-Reactive Protein in Children with Abdominal Sepsis

Abstract

Introduction: Abdominal sepsis in children may progress rapidly to organ dysfunction and adverse outcomes, making early recognition of bacterial infection essential. Procalcitonin (PCT) and C-reactive protein (CRP) are commonly used inflammatory biomarkers, but their comparative diagnostic and prognostic utility in pediatric abdominal sepsis requires further evaluation.

Aim & Objective: To compare the diagnostic performance of procalcitonin (PCT) and C-reactive protein (CRP) and evaluate their association with sepsis severity and clinical outcomes in children with abdominal sepsis.

Material & Methods: This cross-sectional analytical observational study included 100 children aged 5–12 years with abdominal sepsis. Serum PCT and CRP were measured along with appropriate microbiological investigations. Patients were categorized according to sepsis severity and followed for clinical outcomes. Diagnostic performance was assessed using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overall accuracy, and receiver operating characteristic analysis.

Results: The mean age was 8.7 ± 2.2 years; 62% were boys. PCT demonstrated a sensitivity of 84.8%, specificity of 90.7%, PPV of 88.6%, NPV of 87.5%, and diagnostic accuracy of 88.0%. Corresponding values for CRP were 80.4%, 85.2%, 82.2%, 83.6%, and 83.0%, respectively. Median PCT increased from 1.30 ng/mL in mild sepsis to 15.55 ng/mL in severe sepsis, while CRP increased from 22.7 to 167.3 mg/L (p<0.001 for both).  Recovery decreased from 89.3% in mild to 26.7% in severe sepsis, while mortality reached 30.0% in severe cases (p<0.001).

Conclusion: PCT demonstrated better diagnostic performance than CRP in pediatric abdominal sepsis. Both biomarkers correlated with increasing disease severity and clinical outcome. Serial assessment may provide a useful adjunct to clinical and microbiological evaluation for diagnosis, risk stratification, and monitoring of children with abdominal sepsis.

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