Procalcitonin-Based Antibiotic Use for Neonatal Early-Onset Bacterial Infections: Pre- and Post-Intervention Clinical Study.

We previously reported the 95th percentile cutoff value of the serum procalcitonin (PCT) reference curve for diagnosing early-onset bacterial infection. We aimed to verify the effectivity of these novel diagnostic criteria by comparing antibiotic use and incidence of early-onset bacterial infection between pre- and post-introduction periods. We included newborns admitted to our neonatal intensive care unit who underwent blood tests within 72 h after birth between 2018 and 2022. The neonates were divided into the pre-intervention (admitted before the introduction, n = 737) or post-intervention (admitted after the introduction, n = 686) group. The days of antibiotics therapy (DOT) per 1000 patient days up to 6 days after birth, percentage of antibiotic use, and incidence of early-onset bacterial infection were compared between the groups. The post-intervention group had significantly lower DOT per 1000 patient days (82.0 days vs. 211.3 days, p < 0.01) and percentage of newborns receiving antibiotics compared with the pre-intervention group (79 (12%) vs. 280 (38%), respectively, p < 0.01). The incidence of early-onset bacterial infections did not differ between the groups (2% each, p = 0.99). In conclusion, our diagnostic criteria using the 95th percentile cutoff value of the serum PCT reference curve for early-onset bacterial infection were proven safe and effective, promoting appropriate use of antibiotics.

Association of umbilical cord insulin-like growth factor 1 levels with severe retinopathy in extremely preterm infants.

BACKGROUND: The association between umbilical cord blood insulin-like growth factor 1 (IGF-1) levels and retinopathy of prematurity (ROP) remains unclear. This study aimed to investigate whether umbilical cord blood IGF-1 levels can predict the development of severe ROP in extremely preterm infants. METHODS: This hospital-based retrospective cohort study included infants born at <37 weeks gestational age (GA) between 2019 and 2021 and then classified them into the two GA groups: extremely preterm, <28 weeks and preterm infants, 28-36 weeks. Extremely preterm infants were further subclassified into two groups according to the laser treatment as follows: the severe ROP (ROP-Tx) and ROP (No ROP-Tx) groups. Median umbilical cord blood IGF-1 values were compared between the groups. Perinatal risk factors were identified by univariate and multivariate analyses. Finally, umbilical cord IGF-1 cut-off values requiring ROP treatment with laser were determined by receiver operating characteristic (ROC) curve analyses. RESULTS: A total of 205 infants were enrolled, with 32 being extremely preterm (ROP-Tx: n = 11; No ROP-Tx: n = 21) and 173 being preterm. IGF-1 levels were significantly lower in extremely preterm (13.5 ng/mL) than preterm infants (36 ng/mL, p < 0.001). In extremely preterm infants, IGF-1 levels were significantly lower in the ROP-Tx group than the No ROP-Tx group (10 vs. 19 ng/mL, respectively, p = 0.024). Only GA, umbilical cord blood IGF-1 levels, birth head circumference, and birth chest circumference were identified as risk factors by univariate analysis (p < 0.05). Multivariate analysis showed that only umbilical cord blood IGF-1 was an independent risk factor (odds ratio: 1.26, p = 0.021). ROC curves revealed an IGF-1 cut-off value of 14 ng/mL. CONCLUSION: The need of laser treatment for ROP was found to be associated with low umbilical cord blood IGF-1 levels in extremely preterm infants. Umbilical cord blood IGF-1 can be used as a biomarker for the risk of developing severe ROP.

Correction: Go et al. Diagnostic Accuracy of Biomarkers for Early-Onset Neonatal Bacterial Infections: Evaluation of Serum Procalcitonin Reference Curves. Diagnostics 2020, 10, 839.

In the original publication [...].

A prospective cohort study of newborns born to mothers with serum Toxoplasma gondii immunoglobulin M positivity during pregnancy.

INTRODUCTION: The aims were to investigate the clinical characteristics of Toxoplasma gondii (T. gondii) immunoglobulin (Ig) M-positive mothers and to clarify the incidences of serum T. gondii IgM or blood T. gondii DNA positivity in newborns born to the mothers and the actual congenital T. gondii infection. METHODS: Mothers with T. gondii IgM positivity and newborns born to the mothers from 2013 to 2020 were prospectively investigated. Serum T. gondii IgG and IgM were measured by enzyme-linked immunosorbent assay. Blood T. gondii DNA was detected by semi-nested polymerase chain reaction. Congenital T. gondii infection was diagnosed based on clinical characteristic manifestations with serum T. gondii IgG positivity at any age or T. gondii IgG positivity after 12 months of age. RESULTS: Among 71 T. gondii IgM-positive mothers, including one with triplets, 41% had low T. gondii IgG avidity index and 73% received maternal therapy. Among 73 newborns who were examined for serum T. gondii IgG and IgM at birth, none had clinical manifestations, and one (1.4%) had T. gondii IgM positivity. Among 32 newborns who were examined for blood T. gondii DNA at birth, two (6.3%) were positive. All patients with serum T. gondii IgM or blood T. gondii DNA positivity showed T. gondii IgG negativity within 12 months of age. CONCLUSIONS: A few newborns born to T. gondii IgM-positive mothers were suspected of having congenital T. gondii infection based on serum T. gondii IgM or blood T. gondii DNA testing at birth. However, none developed congenital T. gondii infection.

Clinical Evaluation of a Novel Urine Collection Kit Using Filter Paper in Neonates: An Observational Study.

Urine bags are commonly used to collect urine samples from neonates. However, the sample can be contaminated by stool, or detachment of the bag due to body movement can lead to failure of the collection. A qualitative urine collection kit containing ten filter papers of 3.2 mm diameter was developed and clinically verified among 138 neonates. During a single diaper change (approximately 3 h), the rate of urine collection was calculated. Urine collection was considered to be successful if any filter paper in the urine collection sheet turned from blue to white. Of the 127 neonates who passed urine, 122 had a change in the filter paper. The urine collection rate was 96%, with changes in all 10 filter papers observed in 98 neonates (80%). Urine collection rate was not influenced by sex (p = 1.00), age at collection (p = 0.72), preterm birth (p = 1.00), low birth weight (p = 0.92), or fecal contamination (p = 1.00). The incidence of dermatitis was not higher than in the group in which urine bags were used (urine collection kit: 2/68 [3%]; urine bag: 5/68 [7%]; p = 0.44). Novel urine collection kits using filter paper can collect samples from neonates safely and with a high probability of success.

Successful Treatment of Hyperbilirubinemia by Monitoring Serum Unbound Bilirubin in an Extremely Preterm Infant with Bacterial Infection.

BACKGROUND: Bacterial infections and some antibiotics show displacer effects on bilirubin-albumin binding and increase unbound bilirubin (UB) but not total bilirubin (TB) in serum. METHODS: A case study was conducted to show a successful treatment of hyperbilirubinemia by monitoring UB. RESULTS: In an extremely preterm infant with bloodstream bacterial infection caused by methicillin-resistant coagulase-negative staphylococci, 2 days after high-dose ampicillin and regular-dose amikacin were initiated, UB markedly increased, but TB did not. After vancomycin was substituted, UB decreased immediately with phototherapy and intravenous albumin infusion. CONCLUSIONS: When using antibiotics, the clinicians should be mindful regarding the displacer effect on bilirubin-albumin binding.

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

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.

Clinical characteristics of congenital toxoplasmosis with poor outcome in Japan: A nationwide survey and literature review.

The clinical characteristics of congenital toxoplasmosis cases with poor outcomes in Japan were analyzed. Ten cases were selected, identified from a nationwide survey by the Japan Society for Neonatal Health and Development and a literature review. Based on outcomes, two fatal cases showed generalized symptoms at birth; four cases with neurological sequelae showed the three main congenital toxoplasmosis manifestations (chorioretinitis, intracranial calcification, hydrocephalus); four cases with ophthalmological sequelae showed only one or two of the three main manifestations. Eight cases with poor outcomes were not prenatally diagnosed with congenital toxoplasma infection or suspected maternal toxoplasma infection. The outcome of congenital toxoplasmosis might differ depending on the symptomology.

Heart-rate evaluation using fetal ultrasonic Doppler during neonatal resuscitation.

BACKGROUND: The objective of the present study was to verify the speed and accuracy of fetal ultrasonic Doppler (fetal Doppler) in measuring heart rate of newborns at rest, including preterm, low-birthweight infants, and its efficacy during neonatal resuscitation, including cases of neonatal asphyxia. METHODS: A three-lead electrocardiogram and fetal Doppler were used to measure resting heart rates in 100 newborns, including 48 preterm, low-birthweight infants, at 0 to 72 h after birth. Times to display heart rate were compared between electrocardiogram and fetal Doppler by the Bland-Altman analysis and Wilcoxon signed-rank test. The time required for the fetal Doppler to measure heart rate during neonatal resuscitation was also assessed. RESULTS: In 100 newborns, the mean error of the resting heart rate in 1,293 measurement points was 0.07 beats/min. To display the heart rate, the fetal Doppler required a median time of 5 s, and electrocardiogram required a median time of 10 s (P < 0.001). During neonatal resuscitation, the heart rate was measured within 10 s in 18 of 21 cases (86%) and displayed with a median time of 5 s; this was measured in all neonatal asphyxia cases (9/9, 100%). CONCLUSIONS: Fetal Doppler can measure heart rate in newborns accurately and rapidly and is useful for evaluating heart rate not only at rest but also during neonatal resuscitation, especially in asphyxia.