Association between Thyroid Function and Respiratory Distress Syndrome in Preterm Infants.

Thyroid hormones are known to influence the production and secretion of pulmonary surfactant. The objective of this study was to explore the relationship between respiratory distress syndrome (RDS) and thyroid hormones. This was a retrospective study of preterm infants at 24−33 weeks gestational age from April 2017 to February 2019. T3, free T4 (fT4), and thyroid-stimulating hormone (TSH) were measured 1, 3, and 6 weeks after birth. Multivariate logistic regression analyses were performed to determine the relationship between RDS and TSH. A total of 146 infants were enrolled. Of these, 60 had RDS, 72 had no RDS, and 14 were excluded. T3 and TSH were lower in the RDS groups (p < 0.05) on the day of birth. Multivariate logistic regression analysis indicated that lower serum TSH levels immediately after birth were associated with a higher incidence of RDS (OR, 0.89; 95% CI, 0.81−0.97). The TSH level was associated with the incidence of RDS. This suggests that suppression of the hypothalamus−pituitary axis function contributes to RDS, which is the result of surfactant deficiency.

Comparison of neonatal reference intervals for 23 biochemical analytes in the cord blood-A single center study in South Korea.

Choi SJ, Lee S, Lee B, Jang JY, Cho J, Uh Y. Comparison of neonatal reference intervals for 23 biochemical analytes in the cord blood-A single center study in South Korea. Turk J Pediatr 2019; 61: 337-344. Reference intervals for laboratory tests are important in the diagnosis and treatment of disease. However, due to difficulty in recruiting sufficient numbers of reference subjects, studies regarding reference intervals for biochemical analytes in neonates is lacking. The aim of this study was to compare and validate the reference intervals for 23 biochemical analytes in the cord blood of neonates. From August to December 2017, 79 consecutive neonates born at the Wonju Severance Christian Hospital (Wonju, Korea) with C-reactive protein concentration less than 0.05 mg/dL were included in this study. All of 23 biochemical analytes were measured by the cobas 8000 c702 (Roche Diagnostics, Switzerland). Mean ± 2 standard deviations (SD) were calculated if the values were normally distributed, and median and the range of 2.5-97.5 percentile were described when the values were not normally distributed. We compared the neonatal reference intervals for 23 biochemical analytes. Alkaline phosphatase and gamma glutamyl transferase showed significant differences according to sex, and direct bilirubin revealed significant differences depending on the delivery mode. These compared reference intervals of 23 biochemical analytes will be useful for clinical decision-making in the management of neonates.

Interstitial pneumonia pattern on day 7 chest radiograph predicts bronchopulmonary dysplasia in preterm infants.

BACKGROUND: Early identification of infants at higher risk of developing bronchopulmonary dysplasia (BPD) may enable a targeted approach to reduce BPD. We aimed to evaluate the hypothesis that the interstitial pneumonia pattern on the day 7 chest radiograph predicts BPD or death before 36 weeks postmenstrual age (PMA). METHODS: A retrospective cohort study was performed on 336 preterm infants (birth weight < 1500 g and gestational age < 32 postmenstrual weeks) who were admitted to a single tertiary academic center between January 2008 and December 2014. Day 7 chest radiographs were independently reviewed by two pediatric radiologists who were unaware of the clinical information regarding each individual infant. RESULTS: Data from 304 infants who survived more than 7 days after birth were collected. The interstitial pneumonia pattern on the day 7 chest radiograph was independently associated with BPD or death before 36 weeks PMA (odds ratio [OR] 4.0, 95% confidence interval [CI] 1.1-14.4). The interstitial pneumonia pattern on the day 7 chest radiograph predicted BPD or death with a specificity of 98%. Histologic chorioamnionitis was a preceding factor that was independently associated with the interstitial pneumonia pattern on the day 7 chest radiograph (OR 3.7, 95% CI 1.3-10.3). CONCLUSIONS: The interstitial pneumonia pattern on the day 7 chest radiograph has a high specificity for predicting BPD or death and can be utilized to select high-risk preterm infants who will benefit from potentially preventive interventions against BPD.

RNA-Seq for Gene Expression Profiling of Human Necrotizing Enterocolitis: a Pilot Study.

Necrotizing enterocolitis (NEC) characterized by inflammatory intestinal necrosis is a major cause of mortality and morbidity in newborns. Deep RNA sequencing (RNA-Seq) has recently emerged as a powerful technology enabling better quantification of gene expression than microarrays with a lower background signal. A total of 10 transcriptomes from 5 pairs of NEC lesions and adjacent normal tissues obtained from preterm infants with NEC were analyzed. As a result, a total of 65 genes (57 down-regulated and 8 up-regulated) revealed significantly different expression levels in the NEC lesion compared to the adjacent normal region, based on a significance at fold change ≥ 1.5 and P ≤ 0.05. The most significant gene, DPF3 (P < 0.001), has recently been reported to have differential expressions in colon segments. Our gene ontology analysis between NEC lesion and adjacent normal tissues showed that down-regulated genes were included in nervous system development with the most significance (P = 9.3 × 10⁻7; P(corr) = 0.0003). In further pathway analysis using Pathway Express based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, genes involved in thyroid cancer and axon guidance were predicted to be associated with different expression (P(corr) = 0.008 and 0.020, respectively). Although further replications using a larger sample size and functional evaluations are needed, our results suggest that altered gene expression and the genes' involved functional pathways and categories may provide insight into NEC development and aid in future research.