Serum procalcitonin as a predictor of severity of pneumonia in under-five children: A prospective observational study

BACKGROUND: Despite recent advancements in healthcare facilities, the early identification and assessment of pneumonia severity remain major challenges that affect clinical outcomes. These challenges emphasise the necessity for reliable biomarkers that can predict disease severity promptly and precisely. Unlike other markers like C-reactive protein or white blood cell count, procalcitonin (PCT) levels specifically increase in bacterial infections, which are a common cause of severe pneumonia in children. AIM: To evaluate the predictive value of serum PCT in assessing pneumonia severity and clinical outcomes in under-five children. METHODS: This prospective observational study was conducted in a tertiary care teaching hospital in Eastern India from August 2022 to July 2024. Children aged 2 to 59 months admitted with pneumonia underwent serum PCT estimation on day 1 and day 5 of admission. The pneumonia severity was classified as follows: (1) Very severe (intubation, shock, or death); (2) Severe (intensive care admission without very severe features and/or high-flow nasal canula); (3) Moderate (hospitalization without very severe or severe features); and (4) Mild (discharge). Correlation analysis and receiver operating characteristic (ROC) curve analysis were performed to assess the predictive utility of PCT. RESULTS: < 0.01). PCT levels were significantly higher in bacterial pneumonia compared to viral and atypical pneumonia. On day 1, the AUC of PCT in predicting mortality was 0.946 (95%CI: 0.905-0.973), and on day 5, the AUC was 0.948 (95%CI: 0.908-0.975). CONCLUSION: The present study found that serum PCT can predict pneumonia severity including mortality in under-five children. The PCT elevation was significantly higher in bacterial pneumonia compared to viral and atypical pneumonia.