Since December 2019, the coronavirus disease 2019 (COVID-19) has been spreading rapidly worldwide. With the increase in the number of infections, the numbers of pregnant women and newborn infants with COVID-19 are also increasing. According to the limited recent studies, COVID-19 appears to be mainly transmitted to newborn infants by the mother's droplets or direct contact with the mother, and no clear evidence supports the vertical transmission from the mother to the newborn infant. To date, the likelihood of severe outcomes in newborn infants born to mothers with confirmed COVID-19 is relatively very low, but the possibility should be considered. The present response guidelines address the management of newborn infants born to mothers with suspected or confirmed COVID-19. The management covers precautions for birth attendants or medical staffs, testing for COVID-19, isolation, neonatal care, breastfeeding, and mother/baby contact. These response guidelines can be revised in accordance with further updates on COVID-19 and should be adapted to each local health-care facility.

Purpose: Periventricular leukomalacia (PVL) is an important morbidity in preterm infants. Its reported prevalence in very low birth weight (VLBW) infants is 3% to 15% in VLBW infants. PVL develop seizure disorder, intellectual disability, visual problem, and cerebral palsy. This study was done to describe the risk factors of PVL in VLBW infants. Methods: Medical records of 172 VLBW infants at Inje University Ilsan Paik Hospital neonatal intensive care unit were reviewed retrospectively from January 2010 to December 2014. Patients were divided into the non-PVL group (n=155) and the PVL group (n=17). The PVL group included both cystic and non-cystic forms. Demographic findings and factors associated with PVL were compared between these groups. Results: The incidence of non-cystic and cystic PVL was 9.8%. The mean gestational age was significantly lower in the PVL group. The mean birth weight was not significantly different between the groups. The incidences of premature rupture of membrane and pregnancy induced hypertension were not significantly different between the two groups. The number of histologic chorioamnionitis was significantly higher in the PVL group (P<0.05). Other conditions such as respiratory distress syndrome, patent ductus arteriosus, early-onset sepsis, and hypotension were not significantly different between the two groups. The incidence of intravascular hemorrhage (IVH) (grade ≥3) was more significant in the PVL group (P<0.05). Multiple logistic regression analysis indicated that histologic chorioamnionitis (odds ratio [OR], 6.3; 95% confidence interval [CI], 1.1 to 36.3) and IVH (grade ≥3) (OR, 16.9; 95% CI, 1.9 to 153.1) were significant risk factors of PVL. Conclusion: Histologic chorioamnionitis and IVH (grade ≥3) increase the risk of PVL in VLBW infants. Strategies to prevent these conditions could attenuate the incidence of PVL.

Purpose: Inhaled nitric oxide (iNO) is a potent selective pulmonary vasodilator and an important treatment for newborn infants with hypoxic respiratory failure due to persistent pulmonary hypertension of the newborn (PPHN). The Ministry of Food and Drug Safety of Korea first approved iNO in 2009 for use as a new drug to treat hypoxic respiratory failure with PPHN. A post-marketing surveillance study (PMSS) was conducted to assess the effectiveness and safety of the iNO treatment. We evaluated the clinical status of the iNO treatment currently available in Korea by using the PMSS data. Methods: We retrospectively reviewed the PMSS data from 22 hospitals in Korea from October 2014 to September 2018. Altogether, 97 infants were enrolled and divided into early response (ER), delayed response (DR), no response (NR), and death groups according to their response to the iNO treatment. Results: The ER group included 52 infants (53.6%); DR group, 33 (34.0%); NR group, seven (7.2%); and death group, five (5.2%). The iNO treatment was initiated within 14 days after birth at a concentration of 20 ppm. The median treatment duration was 91.5 hours (69.0 to 134.3) in all the infants. Of the infants, 43 (44.3%) received the treatment for >96 hours. Fifty-one infants (52.6%) needed >20 ppm of iNO, and 10 (10.5%) needed a maximum of 80 ppm of iNO. None of the infants had hypermethemoglobinemia or an alarm report of NO₂. Conclusion: Korean neonatologists reported that a large proportion of the infants with PPHN showed improvement in oxygenation after treatment with the approved iNO. These infants received relatively longer durations and higher concentrations of the iNO treatment than the current recommendations, without any side and adverse effect.

Purpose: To identify the recent status of the neonatologist and their workload in neonatal intensive care unit (NICU) in Korea. Methods: On October 2018, a survey was conducted on the statistics of the workforce including the census of certified neonatologists, NICU beds, nursing staffing ratings, bed occupancy rate, annual admission of very low birth weight infant (VLBWI), infant acuity score of nursing, and the proportion of out-born patients. The level of neonatal care was self-rated. Results: A total of 68 centers responded to the survey. An average number of certified neonatologists and the number of NICU beds per center was 1.9 (range, 0 to 5) and 23.1 (range, 0 to 30), respectively. Thirty-eight percent (n=26) of NICUs were being operated with only one (n=24) or no (n=2) certified neonatologist and only 19% (n=13) of NICUs had ≥3 neonatologists. The average ratio of NICU beds to neonatologists rated 13.4±6.2. The higher the level of neonatal care, the higher the number of tertiary referral hospitals, neonatologists, NICU volume, infant acuity scores of nursing, and annual VLBWI admissions. However, there was no difference in the beds to neonatologist ratio between level 2 (n=9, 9.5±3.1), level 3 (n=44, 14.0± 6.9), and level 4 (n=14, 13.7±4.2). The infant acuity score was proportional to the NICU volumes, but not related to the beds to neonatologist ratio. Conclusion: Compared with the international standards, most Korean NICUs were understaffed in terms of the certified neonatologist and were unable to provide 'continuity of care' for high-risk newborns.

Purpose: To identify factors associated with the clinical response to low-dose dexamethasone therapy (LDDT) in preterm infants for bronchopulmonary dysplasia (BPD). Methods: We used a retrospective medical record review to evaluate preterm infants who were born before 32 weeks of gestation or with a birth weight less than 1,500 g. All infants were admitted to the neonatal intensive care unit at a tertiary academic hospital between January 2010 and June 2019, and received LDDT for BPD. The preterm infants' respiratory severity scores (RSS) were calculated from the first day of LDDT to the day of extubation, or the last day of LDDT. A good response was defined as a decreasing RSS with a slope greater than 0.181. A poor response was defined as a non-decreasing RSS, or a decreasing RSS with a slope less than 0.181 during LDDT. A total dose of 1.1 mg/kg was administered for 10 days for each single course of LDDT. Results: A total of 51 preterm infants were included in the final analysis. Thirty preterm infants (58.8 %) were in the good response group, and 21 preterm infants (41.2%) were in the poor response group. There were no significant differences in gestational age, birth weight, and sex between the good response group and poor response group. Preterm premature rupture of membrane and histologic chorioamnionitis were significantly associated with a poor response to LDDT. Higher RSS on the first day of the LDDT was associated with a good response to LDDT. Conclusion: Antenatal infection and/or inflammation may be associated with an unfavorable response to postnatal LDDT for BPD. Preterm infants with more severe respiratory failure seem to benefit more from LDDT for BPD.

Purpose: Association between hyponatremia and the severity of respiratory symptoms in infants with respiratory syncytial virus (RSV) infection has not yet been studied. This study aimed to compare respiratory symptoms, assessed using the Pediatric Respiratory Score (PRS), in infants with RSV infection, with or without hyponatremia. Methods: RSV-positive patients aged <12 months who were admitted with respiratory symptoms within 7 days of onset at Jeonbuk National University Children's Hospital from January 2016 to December 2019 were retrospectively analyzed. Each patient was categorized into those with or without hyponatremia (serum sodium concentration of <136 mmol/L). Clinical findings included PRS on the day of admission. Results: The mean±standard deviation age of the 125 patients included in the study was 2.7±3.3 months, and, 20 patients (16.0%) showed hyponatremia. Infants with RSV infection and hyponatremia had lower birth weights, longer hospital stays, and higher blood urea nitrogen level. The C-reactive protein level was significantly higher in the hyponatremic infants, who had higher PRSs. The non-hyponatremia group had more normal PRSs than the hyponatremia group, which had more severe PRSs. After adjustment for age at admission, blood urea nitrogen level (OR, 1.218; 95% CI, 1.023 to 1.451; P<0.05), and PRS grade (OR, 2.885; 95% CI, 1.158 to 7.187; P<0.05) were identified as independent risk factors. Conclusion: Hyponatremia was strongly associated with respiratory severity in infants with RSV. Therefore, infants admitted with RSV infection who show higher PRS grade need to be evaluated and treated for hyponatremia.

Here we present a rare case of pulmonary arterial thrombosis associated with a ductus arteriosus aneurysm that caused severe pulmonary stenosis. A 5-day-old newborn was admitted to our hospital for the evaluation of an intracardiac mass-like lesion found after the detection of a cardiac murmur. Echocardiography and heart computed tomography revealed a mass-like lesion measuring 8.1 mm in diameter across the distal main pulmonary artery to the proximal left pulmonary artery resulting in localized severe stenosis of the left pulmonary artery. Left pulmonary artery angioplasty for surgical resection of the thrombus revealed that the mass was adherent to the proximal part of the left pulmonary artery anterior wall and extended to the ductus arteriosus. Histological examination of the mass showed an old thrombus with dystrophic calcification. Five months after surgery, follow-up echocardiography showed that the left pulmonary artery peak pressure gradient had decreased but the proximal left pulmonary artery stenosis remained. Cardiac catheterization and balloon angioplasty successfully relieved the pulmonary stenosis.

Neonatal acute suppurative parotitis is rare. Staphylococcus aureus is the most common pathogen and antibiotic treatment is the first line therapy. Here, we report a case of acute suppurative parotitis caused by Escherichia coli in a 7-day-old male with febrile sensation, parotid swelling, and purulent discharge from the Stensen duct who was treated successfully with intravenous antibiotics. To the best of our knowledge, this is the first case of neonatal suppurative parotitis caused by E. coli in Korea.