Kim JK, et al. J Korean Med Sci. 2016 Mar;31(3):423-429. http://dx.doi.org/10.3346/jkms.2016.31.3.423

To investigate the trends in the incidence and associated factors of late-onset sepsis (LOS) associated with improved survival in extremely preterm infants. Medical records of 364 infants who were born at 23–26 weeks’ gestation from 2000 to 2005 (period I, n = 124) and from 2006 to 2011 (period II, n = 240) were retrospectively reviewed. The infants were stratified into subgroups of 23–24 and 25–26 weeks’ gestation within each period, and survival, LOS rate, and clinical characteristics were analyzed. Multivariate logistic regression analyses were completed to identify the clinical factors associated with LOS. The survival rate of 75.8% during period I significantly improved to 85.4% during period II, especially in infants at 23–24 weeks’ gestation (55.1% vs. 78.1%, respectively). The LOS rate of 33.1% during period I significantly reduced to 15.8% during period II, especially in infants at 25–26 weeks’ gestation (32.0% vs. 8.9%, respectively). The LOS rate per 1000 hospital days of 4.0 during period I significantly reduced to 1.8 during period II. Candida presence reduced from 21.3% during period I to 4.7% during period II. In multivariate analyses, during period I, prolonged intubation, especially in infants at 25–26 weeks’ gestation, and necrotizing enterocolitis, especially in infants at 23–24 weeks’ gestation, were significantly associated with LOS. Improved survival of infants at 23–24 weeks’ gestation was associated with a simultaneous reduction of LOS incidence in infants at 25–26 weeks’ gestation. Less-invasive assisted ventilation may be one of the details of improved perinatal and neonatal care that has contributed to lowering risk of infection or death among periviable infants.

The effects of improved survival of EPT infants on morbidity among survivors remain largely controversial. This retrospective cohort study of the Korean Neonatal Network data investigated whether the mortality rate of 23–24 weeks’ gestation was associated with survival without major morbidities in periviable 25–26 weeks’ gestation infants. The 2,083 eligible infants with 23–26 weeks’ gestation were grouped based on institutional mortality rate (group 1 and 2 ≤50% and >50% mortality rate, respectively, for 23–24 weeks’ gestation) and were further divided into 23–24 and 25–26 weeks’ gestation subgroups. The mortality rate of 23–24 weeks’ gestation infants was significantly lower in group 1 (32.7%) than in group 2 (69.9%). The survival without major morbidities rate for 25–26 weeks’ gestation infants was significantly higher in group 1 (31.2%) than in group 2 (18.5%). Antenatal steroid use and Apgar score at 5 min in group 1 were associated with decreased mortality and survival without major morbidities in 23–24 and 25–26 weeks’ gestation infants, respectively. In the multivariate analyses, decreased mortality rates in 23–24 weeks’ gestation infants were associated with higher survival without major morbidities rates in 25–26 weeks’ gestation infants due to decreased bronchopulmonary dysplasia, periventricular leukomalacia, and late-onset sepsis. Evidence-based perinatal and neonatal practices, including antenatal steroid use and better delivery room care contributing to decreased mortality in periviable 23–24 weeks’ gestation infants, were associated with lower morbidity and higher survival without major morbidities in more mature 25–26 weeks’ gestation infants.

Preterm birth prediction is essential for improving neonatal outcomes. While many machine learning techniques have been applied to predict preterm birth using health records, inflammatory markers, and vaginal microbiome data, the role of prenatal oral microbiome remains unclear. This study aimed to compare oral microbiome compositions between a preterm and a full-term birth group, identify oral microbiome associated with preterm birth, and develop a preterm birth prediction model using machine learning of oral microbiome compositions. Participants included singleton pregnant women admitted to Jeonbuk National University Hospital between 2019 and 2021. Subjects were divided into a preterm and a full-term birth group based on pregnancy outcomes. Oral microbiome samples were collected using mouthwash within 24 h before delivery and 16S ribosomal RNA sequencing was performed to analyze taxonomy. Differentially abundant taxa were identified using DESeq2. A random forest classifier was applied to predict preterm birth based on the oral microbiome. A total of 59 women participated in this study, with 30 in the preterm birth group and 29 in the full-term birth group. There was no significant difference in maternal clinical characteristics between the preterm and the full-birth group. Twenty-five differentially abundant taxa were identified, including 22 full-term birth-enriched taxa and 3 preterm birth-enriched taxa. The random forest classifier achieved high balanced accuracies (0.765 ± 0.071) using the 9 most important taxa. Our study identified 25 differentially abundant taxa that could differentiate preterm and full-term birth groups. A preterm birth prediction model was developed using machine learning of oral microbiome compositions in mouthwash samples. Findings of this study suggest the potential of using oral microbiome for predicting preterm birth. Further multi-center and larger studies are required to validate our results before clinical applications.

Charcot–Marie–Tooth disease (CMT) is typically an autosomal dominant, inherited neuropathy, although there is a rare male X-linked CMT. Such patients show central nervous system (CNS) involvement in addition to peripheral neuropathy. Recently, we encountered a patient who presented with acute disseminated encephalomyelitis (ADEM)-like symptoms, but was later diagnosed as having X-linked CMT (CMTX) due to a mutation. A previously healthy 11-year-old boy was admitted for a sudden transient weakness of his left side extremities. The patient was diagnosed with left side hemiparesis. Brain magnetic resonance imaging (MRI) showed ADEM-like demyelinating lesions on both centrum semiovale. A diagnosis of probable ADEM was made, and the patient soon recovered. After 4 months, a second MRI showed complete resolution of the brain lesions. However, the symptoms recurred 2 years later. A third MRI revealed white matter abnormalities, and a physical examination demonstrated pes cavus deformities and peripheral muscle wasting of both lower extremities. On the basis of the brain MRI lesions and physical findings, we suspected CMTX. Genotyping confirmed a mutation in the GJB1 gene. When the symptoms recurred 2 years later, dysarthria and demyelinating MRI lesions were present. We could not identify any triggering factors. Differential diagnosis of recurrent ADEM-like lesions in the cerebral white matter and peripheral neuropathy should include the possibility of CMTX disease.