Prospective Observational Study to Determine Kinetics of Procalcitonin in Hospitalized Children Receiving Antibiotic Therapy for Non-Critical Acute Bacterial Infections

Introduction: The kinetics of procalcitonin in pediatric patients with non-critical acute bacterial infections receiving appropriate antibiotic therapy are not well described. Methods: We performed a single-center, prospective observational pilot study of children admitted to a tertiary care children’s hospital who were receiving antibiotics for treatment of a non-critical acute bacterial infection, and we prospectively measured serial procalcitonin levels daily for 4 days during hospitalization. Results: Among the 46 children with baseline procalcitonin levels enrolled in the study, procalcitonin kinetics followed a half-life of approximately 24 h in most patients. Procalcitonin declined faster than C-reactive protein over the first 48 h of appropriate antibiotic treatment. There was variation in biomarker levels among participants with the same infection type, especially in participants with bacteremia, musculoskeletal infection and skin/soft tissue infection. Conclusion: Utility of procalcitonin as a biomarker to follow every 24–48 h in non-critically ill children receiving antibiotic therapy for bacterial infections as an objective measure of clinical improvement is promising.