Background: Achieving a definitive genetic diagnosis of unexplained multiple congenital anomalies (MCAs) in neonatal intensive care units (NICUs) infants is challenging because of the limited diagnostic capabilities of conventional genetic tests. Although the implementation of whole genome sequencing (WGS) has commenced for diagnosing MCAs, due to constraints in resources and faculty, many NICUs continue to utilize chromosomal microarray (CMA) and/or karyotyping as the initial diagnostic approach. We aimed to evaluate the diagnostic efficacy of WGS in infants with MCAs who have received negative results from karyotyping and/or CMA. Methods: In this prospective study, we enrolled 80 infants with MCAs who were admitted to a NICU at a single center and had received negative results from CMA and/or karyotyping.The phenotypic characteristics were classified according to the International Classification of Diseases and the Human Phenotype Ontology. We assessed the diagnostic yield of trioWGS in infants with normal chromosomal result and explored the process of diagnosing by analyzing both phenotype and genotype. Also, we compared the phenotype and clinical outcomes between the groups diagnosed with WGS and the undiagnosed group. Results: The diagnostic yield of WGS was 26% (21/80), of which 76% were novel variants.There was a higher diagnostic yield in cases of craniofacial abnormalities, including those of the eye and ear, and a lower diagnostic yield in cases of gastrointestinal and genitourinary abnormalities. In addition, higher rates of rehabilitation therapy and gastrostomy were observed in WGS-diagnosed infants than in undiagnosed infants. Conclusion This prospective cohort study assessed the usefulness of trio-WGS following chromosomal analysis for diagnosing MCAs in the NICU and revealed improvements in the diagnostic yield and clinical utility of WGS.

Purpose: Hypothermia upon admission to the neonatal intensive care unit (NICU) contributes significantly to various neonatal complications, particularly in preterm infants. This study aimed to assess the impact of quality improvement (QI) interventions, including using plastic bags and head caps, and adjusting delivery room temperatures, on improving the admission body temperature and reducing hypothermia in infants born at less than 32 weeks or weighing 1,500 g. Methods: This study retrospectively analyzed the medical records of infants born at less than 32 weeks or weighing 1,500 g who admitted to the NICU at Samsung Medical Center from January 2022 to February 2024. The QI program that was initiated in April 2023 focused on managing admission temperatures using plastic bags and head caps, and maintaining delivery room temperatures at ≥25 °C. The admission temperature and short-term outcomes pre- and post-QI were compared. Results: In a study of 270 patients, implementing QI initiatives significantly raised the admission temperature from 36.2±0.5 to 36.4±0.4 °C (p<0.01), particularly impacting infants weighing ≥1,000 g, in whom mild hypothermia occurrences dropped from 76.3% to 43.9% (p<0.01). This improvement in temperature management significantly decreased both mild and severe hypothermia rates post-QI. Additionally, implementing all three initiatives was more effective than when two or fewer initiatives were implemented. Conclusion Simple and cost-effective QI interventions can increase admission temperatures and decrease hypothermia in neonates. Further research is essential to explore the long-term outcomes and develop effective hypothermia management strategies in neonatal care.

Purpose: To investigate the risk factors associated with hypospadias in very low birth weight (VLBW) infants (VLBWIs). Methods: We retrospectively analyzed 729 infants born at ≥24 weeks of gestational age and weighing <1,500 g from January 2012 to December 2022. We assessed the prevalence of hypospadias by birth weight percentiles and also compared the demographics and placental histopathology of the infants with hypospadias (n=52) and those without hypospadias (n=677). Results: Of the 729 patients analysed, hypospadias was recorded in 26 (20.3%), 14 (26.9%), and 12 (2.5%) infants in the <3rd, ≥3rd–<10th, and ≥10th–<90th percentiles, respectively. Of all of the patients with hypospadias, 50% had birth weights <3rd percentile (p<0.001). The hypospadias group demonstrated a longer mean gestational age (30.1 weeks vs. 27.9 weeks, p<0.001), lower incidence of maternal pregnancy-induced hypertension (48.1% vs. 17.3%, p<0.001), lower incidence of premature rupture of membrane (11.5% vs. 27.1%, p=0.013), lower acute chorioamniotic maternal response (9.1% vs. 35.2%, p<0.001), and higher maternal underperfusion (95.5% vs. 71.9%, p<0.001). Conclusion The frequency of hypospadias was found to be the highest among VBLWIs <3rd percentile, who were severely small for their gestational age (SGA). Additionally, the incidence increased with a decreasing birth weight. Physical examination is necessary at birth for VLBWIs classified as SGA. Moreover, the data on the incidence of hypospadias among VLBWIs in neonatal intensive care units can assist in tracking counseling from the prenatal to the postnatal period for patients born <3rd percentile.

Background: Despite the popularity of the NeoBase 2 Non-derivatized MSMS assay (PerkinElmer, Turku, Finland), there are no reports of its comprehensive evaluation, including the ability to distinguish transient tyrosinemia of the newborn (TTN) from tyrosinemia type 1 (TYR 1) using succinylacetone (SUAC). No newborn screening (NBS) cutoffs for preterm neonates in the Korean population have been suggested. We evaluated the NeoBase 2 assay and identified analytes requiring different cutoffs in preterm neonates. Methods: Residual NBS dried blood spot samples and proficiency testing (PT) materials of the Newborn Screening Quality Assurance Program and the Korean Association of External Quality Assessment Service were used. Precision, accuracy, limit of detection (LOD), lower limit of quantification (LLOQ), linearity, recovery, carryover, and performance of SUAC were evaluated. Cutoffs were determined, and analytes requiring different cutoffs in preterm neonates were investigated. Results: Mean CVs for within-run and between-day precision were within 15%. Accuracy analysis indicated high agreement with in-house derivatized assay results and results of other PT participants. All analytes demonstrated acceptable LOD, LLOQ, and linearity. Recoveries were acceptable, except for SUAC. Carryover was negligible. Cutoffs were established for all analytes; Tyr, adenosine, and C20:0-lysophosphatidylcholine required different cutoffs in preterm neonates. Differential diagnosis of TYR 1 and TTN was successful with simultaneous Tyr and SUAC measurement. Conclusions The NeoBase 2 assay demonstrated satisfactory performance. The additional analytes provide a wider diagnostic coverage, and the simultaneous measurement of Tyr and SUAC is efficient in excluding TYR 1. The new cutoffs for preterm neonates may decrease false-positive rates, without compromising diagnostic sensitivity.

Background: Although the overall quality of high-risk neonatal care has improved recently, there is still concern about a difference in the quality of care when comparing off-hour births and regular-hour births. Moreover, there are no data in Korea regarding the impact of time of birth on mortality and morbidities in preterm infants. Methods: A total of 3,220 infants weighing < 1,000 g and born at 23–34 weeks in 2013–2017 were analyzed based on the Korean Neonatal Network data. Mortality and major morbidities were analyzed using logistic regression according to time of birth during off-hours (nighttime, weekend, and holiday) and regular hours. The institutes were sub-grouped into hospital group I and hospital group II based on the neonatal intensive care unit (NICU) care level defined by the mortality rates of < 50% and ≥ 50%, respectively, in infants born at 23–24 weeks' gestation. Results: The number of births during regular hours and off-hours was similar. In the total population and hospital group I, off-hour births were not associated with increased neonatal mortality and morbidities. However, in hospital group II, increased early mortality was found in the off-hour births when compared to regular-hour births. Conclusion Efforts to improve the overall quality of NICU are required to lower the early mortality rate in off-hour births. Also, other sensitive indexes for the evaluation of quality of NICU care should be further studied.

Background: Although the overall quality of high-risk neonatal care has improved recently, there is still concern about a difference in the quality of care when comparing off-hour births and regular-hour births. Moreover, there are no data in Korea regarding the impact of time of birth on mortality and morbidities in preterm infants. Methods: A total of 3,220 infants weighing < 1,000 g and born at 23–34 weeks in 2013–2017 were analyzed based on the Korean Neonatal Network data. Mortality and major morbidities were analyzed using logistic regression according to time of birth during off-hours (nighttime, weekend, and holiday) and regular hours. The institutes were sub-grouped into hospital group I and hospital group II based on the neonatal intensive care unit (NICU) care level defined by the mortality rates of < 50% and ≥ 50%, respectively, in infants born at 23–24 weeks' gestation. Results: The number of births during regular hours and off-hours was similar. In the total population and hospital group I, off-hour births were not associated with increased neonatal mortality and morbidities. However, in hospital group II, increased early mortality was found in the off-hour births when compared to regular-hour births. Conclusion Efforts to improve the overall quality of NICU are required to lower the early mortality rate in off-hour births. Also, other sensitive indexes for the evaluation of quality of NICU care should be further studied.

Purpose: Minute T1 colorectal cancer (CRC) lesions (≤5 mm) are rare; however, little is known about their characteristics and aggressiveness. In this study, we evaluated the characteristics of minute T1 CRC in relevance to pathology and treatment. Methods: This retrospective study included 849 patients with T1 CRC endoscopically or surgically treated between January 2001 and December 2016. The patients were stratified into 4 groups according to tumor size; minute group (≤5 mm), small group (6–10 mm), medium group (11–20 mm), and large group (≥21 mm). Clinicopathological variables were evaluated with respect to tumor size. Results: The incidence of the minute T1 CRC was 2.4% (20 of 849). Minute T1 CRC was significantly associated with flat type (minute, 25%; small, 12.6%; medium, 8.8%; large, 12.6%; P = 0.016), right-sided cancer (30%, 15.4%, 15.4%, 15.1%, P = 0.002) and the absence of background adenoma (BGA) (50%, 40.7%, 32.8%, 18.1%, P < 0.001). In patients who underwent surgery, lymph node metastasis (LNM) was significantly higher in the minute group (36.4%, 15.9%, 15.7%, 9.2%, P = 0.029). Conclusion Minute T1 CRC is significantly associated with flat type, right-sided cancers, as well as with the absence of BGA and LNM. These results suggested the minute T1 CRC lesions are often aggressive and are likely to be missed during colonoscopy.

Purpose: Although many studies have evaluated the association between intestinal microorganisms and the risk of colorectal cancer (CRC), only a few studies have investigated the changes in microorganisms following curative treatment for CRC. The current study analyzed changes in intestinal microbiota following curative surgery in CRC patients. Methods: Stool samples were collected before and 6 months after surgery, from 11 patients with clinical stage III CRC, who underwent curative surgery between May 2017 and June 2017. Next, 16S rRNA gene sequencing was performed. Operational taxonomic units (OTUs) and alpha diversity were evaluated using the Shannon index. The bacterial compositions of the stools were analyzed according to taxonomic rank at genus and phylum levels. Results: OTUs and alpha diversity were significantly decreased following surgery (P < 0.001 and P = 0.019, respectively). The compositions of several bacterial taxa changed after surgery. At genus level, proportions of pathogens such as Campylobacter, Fusobacterium, Haemophilus, Porphyromonas, and Prevotella, decreased after surgery (adjusted P < 0.05). At phylum level, the proportion of Fusobacteria decreased after surgery (adjusted P < 0.001). Conclusion Significant changes in intestinal microbial communities were noted following curative resection of CRC patients. Especially, decreases in pathogenic bacterial populations, such as Fusobacterium and Prevotella, which are known to be associated with CRC development, were detected even though OTUs and alpha diversity were decreased following curative resection. To determine and validate the clinical significance of these findings, large scale, prospective studies that include cancer prognoses are required.

The paper by Huh et al. [1] was printed with an error the name and affiliation of author.