Serial Procalcitonin Levels and Clinical Parameters in Critically Ill Pediatric Patients: A Prospective Longitudinal Study

Aims and background:The serial trend of procalcitonin (PCT) levels rather than a single value is helpful in real clinical practice.More insight into the disease progression or recovery is possible if it is combined with trends of clinical parameters.To gain insight into PCT trends and their relationship with several clinical parameters, this study was undertaken. Materials and methods:The study was conducted in a seven-bed pediatric intensive care unit (PICU).Pediatric patients aged from 1 month to 18 years admitted with suspected severe sepsis and/or significant organ dysfunction were included.On day 1 of admission, PCT level was measured.PCT levels were repeated on the 5th, 7th, 10th, and 14th days of admission.The clinical parameters for comparison were the degree of fever, respiratory rate, maximum heart rate, heart rate variability, Glasgow Coma Scale (GCS), need for mechanical ventilation, oxygen supplementation or inotropes, and establishment of feeding/feeding tolerance.Results: A total of 37 patients were enrolled.The median (Q1, Q3) age was 36 (12.5, 72) months, 17/37 (46%) were under 5 years of age and 19/37 (51.5%) were males.The first-day PCT of more than 10 ng/mL was observed in 17 (45.95%)patients.The median (Q1, Q3) of PCT on day 1 and day 5 was 8.8 (1.2, 44.9) and 10 (1.25-52.4)ng/mL, respectively, followed by a decreasing trend.At PCT cut-off level of 10 ng/mL, on day 1, inotrope requirement was >10 μg/kg/minute; on day 5, heart rate variability was more than 40 beats/minute, and on day 7, establishment of feeding/better feeding tolerance was statistically significant (p-values: 0.008, 0.041, and 0.036, respectively). Conclusion:The need for inotropes, heart rate variability, and feeding tolerance shows a relationship at the PCT cut-off level of 10 ng/mL.Clinical significance: By combining several clinical parameters with the values of PCT, serial monitoring helps in better management in critically ill children and decision-making of judicious use of ordering PCT, which is an important sepsis marker.