Utilization of serum procalcitonin as a biomarker in the diagnosis and treatment of children with bacterial hospital-acquired pneumonia

Hospital-acquired pneumonia (HAP) is one of the common infections in hospitalized patients. Early and prompt diagnosis of HAP is important because it aids in the appropriate selection of antibiotics and decreases the mortality and morbidity of patients. The investigation on serum procalcitonin (PCT) levels in pediatric patients is limited. Herein we aimed to evaluate the role of PCT in the early diagnosis of children with bacterial HAP. The study enrolled 264 children (< 14 years old) who were radiographically detected by pulmonary condensation chest X-rays. The HAP patients were stratified by patterns of microbiological detection of pathogens. Baseline white blood cell (WBC) count, neutrophil proportion, PCT, and C-reactive protein (CRP) were measured on admission. The laboratory findings and microbiological findings were analyzed and compared among groups. The median PCT concentration of patients with typical bacterial pathogens (3.95 ± 3.75 ng/mL) was significantly higher than the one of the patients with other pathogen types (median lower than 1.20 ng/mL). Correlation analysis indicated a significant correlation between PCT concentrations and the main inflammation makers including WBC count, neutrophil proportion, and CRP. PCT level was significantly decreased to 0.86 ± 1.46 ng/mL in post-treatment patients (p < 0.001). This cohort study with 264 pediatric HAP patients demonstrated the reliability of PCT level as a biomarker in patients with typical bacterial pathogens. Specifically, PCT cutoffs of 2 ng/mL accurately identified HAP children with typical bacterial pathogens. This finding suggested that PCT may serve as a reliable biomarker for the early diagnosis and treatment indicator of children with HAP.