Newborn Screening for Spinal Muscular Atrophy: A 2.5-Year Experience in Hyogo Prefecture, Japan.

Newborn screening (NBS) for spinal muscular atrophy (SMA) is necessary, as favorable outcomes can be achieved by treatment with disease-modifying drugs in early infancy. Although SMA-NBS has been initiated in Japan, its clinical results have not been fully reported. We report the findings of the initial 2.5 years of a pilot SMA-NBS of approximately 16,000 infants conducted from February 2021 in Hyogo Prefecture, Japan. Clinical data of 17 infants who tested positive were retrospectively obtained from the NBS follow-up centers participating in this multicenter cohort observational study. Genetic testing revealed 14 false positives, and three infants were diagnosed with SMA. Case 1 had two copies of survival motor neuron (SMN) 2 and showed SMA-related symptoms at diagnosis. Case 2 was asymptomatic, with two copies of SMN2. Asymptomatic case 3 had four copies of SMN2 exon 7, including the SMN1/2 hybrid gene. Cases 1 and 2 were treated within 1 month and case 3 at 8 months. All the patients showed improved motor function scores and did not require respiratory support. The identification of infants with SMA via NBS and early treatment improved their motor and respiratory outcomes. Thus, implementation of SMA-NBS at a nationwide scale should be considered.

The Occurrence of Early-Onset Neonatal Streptococcus pneumoniae Infection as a Result of Intrapartum Infection.

Early-onset neonatal infection caused by Streptococcus pneumoniae occurs rarely but has a high mortality rate. Due to the low detection rate of S. pneumoniae in maternal vaginal cultures, administering prophylactic antibiotics for S. pneumoniae to mothers before delivery is challenging. Herein, we present the case of a male newborn who was born at 38 weeks of gestation. The vaginal cultures of his mother before delivery did not reveal the presence of group B streptococcus (GBS) and S. pneumoniae. The newborn experienced respiratory distress six hours after birth and was diagnosed with congenital pneumonia. He was successfully treated with an artificial ventilator and antibiotics. The nasal cavity, external ear canal, and transtracheal tube sputum cultures of the neonate and the vaginal cultures of his mother were positive for S. pneumoniae serotype 3. This case indicates the occurrence of congenital S. pneumoniae infection as a result of intrapartum infection and highlights the necessity to consider S. pneumoniae as a causative agent of early-onset neonatal infection.

Evaluation index for asymmetric ventricular size on brain magnetic resonance images in very low birth weight infants.

OBJECTIVE: Asymmetric ventriculomegaly is often evident on brain magnetic resonance imaging (MRI) in very low birth weight infants (VLBWI) and is interpreted as white matter injury. However, no evaluation index for asymmetric left-right and anterior-posterior ventricular sizes has been established. METHODS: In this retrospective multicenter cohort study, brain T2-weighted MRI was performed at term-equivalent ages in 294 VLBWI born between 2009 and 2011. The value of a lateral ventricular index (LVI) to evaluate asymmetric ventricular size, as well as the relationship between the LVI value and walking at a corrected age of 18 months was investigated. At the level of the foramen of Monro in a horizontal slice, asymmetry between the left and right sides and between the anterior and posterior horns was identified by the corrected width and was detected by a low concordance rate and κ statistic value. An LVI representing the sum of the widths of the four horns of the lateral ventricle corrected for cerebral diameter was devised. RESULTS: Asymmetric left-right and anterior-posterior ventricular sizes were confirmed. The LVI value was significantly higher in the non-walking VLBWI group (n = 39) than in the walking VLBWI group (n = 255; 18.2 vs. 15.8, p = 0.02). An LVI cut-off value of 21.5 was associated with non-walking. Multivariate analysis revealed that an LVI value >21.5 was an independent predictor of walking disability at the corrected age of 18 months (odds ratio 2.56, p = 0.008). CONCLUSIONS: The LVI value calculated via MRI may predict walking disability at a corrected age of 18 months in VLBWI.

Prophylactic indomethacin in extremely premature infants between 23 and 24 weeks gestation.

BACKGROUND: In extremely premature infants, the presence of a left-to-right shunt through a patent ductus arteriosus (PDA) increases the risks of pulmonary hemorrhage, intraventricular hemorrhage, necrotizing enterocolitis, renal failure, and chronic lung disease. Conservative management induces spontaneous ductus closure in <20% of extremely premature infants (infants born at <25 weeks of gestation). The aim of the present study was to determine the efficacy and safety of prophylactic indomethacin (INDO) administration for PDA closure in extremely premature infants born between 23 and 24 weeks of gestation. METHODS: A historical case-control study of 30 infants born between 23 and 24 weeks of gestation was carried out. In the prophylactic INDO group, a 12 h-long, 0.01 mg/kg per h dose of INDO was administered within 6 h of life. During the historical control period, only infants with symptomatic PDA were treated with INDO for 1 h. The incidence of symptomatic PDA, mortality and early neonatal morbidity was compared between the two groups on Fisher's exact test and Mann-Whitney rank-sum test. RESULTS: None of the infants in the prophylactic INDO group had symptomatic PDA, while 11 of the 15 infants in the control group showed symptomatic PDA (P < 0.001). There were no significant differences between the mortality rates and the early neonatal morbidities in the two groups. CONCLUSIONS: Prophylactic INDO administration to extremely premature infants born between 23 and 24 weeks of gestation decreased the incidence of symptomatic PDA without increasing the incidence of adverse effects.