Clinical Availability of Serum Procalcitonin Level in the Diagnosis of Neonatal Bacterial Infection

Kim, Ee Kyung; Lee, Byong Sop; Lee, Jin A; Jo, Heui Seung; Park, June Dong; Kim, Beyong Il; Choi, Jung Hwan

Abstract

PURPOSE: The identification of the infected neonate remains one of the most difficult tasks in clinical medicine. We evaluated the reliability and clinical availability of serum concentrations of procalcitonin (PCT) for the diagnosis of neonatal bacterial infection in a neonatal intensive care unit.
METHODS
Timed PCT determinations were prospectively obtained in 33 newborns during 2-month period. The relationship between serum PCT concentrations and the development of neonatal bacterial infection was examined. Concentrations of PCT were measured by specific immunoluminometric assay.
RESULTS
The study population composed of 12 newborns with bacterial infection, 18 without infection, 1 with viral infection, and 2 with uncertain status. Two postnatal periods were set according to the hour-specific 95% reference range for PCT in the first 48 hours: 0-48 hours of age (period) and 3-60 days of age (period). PCT in period was more sensitive (100% vs 40%), but less specific (80% vs 100%) than C-reactive protein (CRP) for neonatal bacterial infection. In period, PCT and CRP had same sensitivity (57.1%) and specificity (100%). As a whole, first measured PCT and CRP were significant for the diagnosis of bacterial infection. The odds ratio of PCT was 34.0. The next day's follow-up measurements of PCT was also significant, but CRP was not.
CONCLUSION
As PCT showed equivalent or better sensitivity than CRP and acceptable specificity, it seems to be helpful to measure PCT concentrations when the possibilities of bacterial infection is to be answered in the neonatal period. But regarding the cost of PCT test which is several times more expensive than CRP test, it seems to be hard to use the PCT test as a routine diagnostic tool for neonatal bacterial infection.