Extrapontine myelinolysis (EPM) is an uncommon disorder in children, with few pediatric cases reported to date. We report the first case of an infant with EPM without central pontine myelinolysis (CPM) presenting with severe hypernatremia. On admission, the infant had impaired consciousness, mild dehydration, and severe hypernatremia (190 mmol/L). The following day, the patient developed abnormal involuntary movements. Brain magnetic resonance imaging (MRI) confirmed EPM without CPM. He recovered without sequelae, and clinical examinations were within normal limits approximately 6 months after discharge. Brain MRI at 1 year after onset showed complete disappearance of the previous EPM regions. To the best of our knowledge, this represents the youngest patient with EPM without CPM presenting with severe hypernatremia. Given that treatment for osmotic demyelination syndrome (ODS) is yet to be established, preventing the development of ODS is crucial.

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.

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.

Neonatal mitochondrial disease is occasionally observed in patients with intraventricular cysts in the brain. Atypical morphology is rarely seen in these cysts. Here, we report a case of neonatal lethal mitochondrial disease with IBA57 gene mutation. We have, for the first time, described a subependymal pseudocyst (SEPC) with a fluctuating membrane. Our findings suggest that SEPCs with fluctuating membranes can be a potential diagnostic indicator of neonatal mitochondrial disease.

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.