Abstract
To date, no clinical studies have compared the accuracy of serum procalcitonin (PCT) reference curves. We aimed to validate the diagnostic accuracy of previously reported serum PCT reference curves and to determine which biomarkers among a cut-off value over the 95th percentile in the serum PCT reference curve, white blood cell (WBC) count, and C-reactive protein (CRP) and immunoglobulin M (IgM) levels, have the highest diagnostic accuracy for early-onset neonatal bacterial infections. This retrospective cohort study assessed 16 preterm and 23 term infants with suspected bacterial infections within 72 h after birth. Each infant group was divided into two subgroups: confirmed- and non-infection. The diagnostic accuracy was determined using the Youden index. The reference curves by Fukuzumi et al. in preterm and term infants had the highest Youden indexes: 1.000 and 0.324, respectively. Among preterm infants, the Youden index for PCT was 1.000. Among term infants, the Youden index for a combination of PCT, CRP, and WBC and/or IgM was 1.000. In conclusion, a serum PCT level over the 95th percentile on the reference curve for preterm infants and a combination of PCT and CRP levels with WBC count and/or IgM levels for term infants provided sufficient diagnostic accuracy.
Highlights
Diagnosis and treatment of early-onset bacterial infections in neonates are important because they have a high mortality rate and result in serious sequelae [1,2,3]
No significant difference was found in the age of measurement of infection biomarkers between the two groups, PCT and C-reactive protein (CRP) levels were significantly higher, and white blood cell (WBC) count was significantly lower in the confirmed infection group than in the non-infection group
We found that the serum PCT level over the 95th percentile on the reference curve had sufficient diagnostic accuracy for detecting early-onset bacterial infections among preterm infants, whereas a combination of PCT and CRP levels with WBC count and/or immunoglobulin M (IgM) level provided sufficient diagnostic accuracy among term infants
Summary
Diagnosis and treatment of early-onset bacterial infections in neonates are important because they have a high mortality rate and result in serious sequelae [1,2,3]. Count and serum C-reactive protein (CRP), immunoglobulin M (IgM), and procalcitonin (PCT) levels are commonly used as biomarkers for early-onset neonatal bacterial infections in clinical settings worldwide [4,5,6,7]. The CRP level is elevated in the presence of other diseases, such as collagen diseases, malignancies, and asphyxia, other than infectious diseases [8,9]. An elevated IgM level in neonates at birth is a biomarker of Diagnostics 2020, 10, 839; doi:10.3390/diagnostics10100839 www.mdpi.com/journal/diagnostics
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
