Diagnostic Accuracy of Biomarkers for Early-onset Neonatal Bacterial Infections: Evaluation of Serum Procalcitonin Reference Curves

• Main Authors: Hidetoshi Go, Nobuhiko Nagano, Daichi Katayama, Takuya Akimoto, Takayuki Imaizumi, Ryoji Aoki, Midori Hijikata, Ayako Seimiya, Ryota Kato, Aya Okahashi, Ichiro Morioka
• Format: Article
• Language: English
• Published: MDPI AG 2020-10-01
• Series: Diagnostics
• Subjects: C-reactive protein; immunoglobulin M; sensitivity; sepsis; specificity; white blood cell
• Online Access: https://www.mdpi.com/2075-4418/10/10/839
• ISSN: 2075-4418

<b> </b>To date, no clinical studies have compared the accuracy of serum procalcitonin (PCT) reference curves.<b> </b>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.