Scrotal Abscess Following Emergency Laparotomy in a Preterm Infant / 계명의대학술지

We report one rare case of scrotal abscess following an emergency laparotomy in a preterm infant. A male infant was born by cesarean section due to twin pregnancy at 34 weeks of gestation. He underwent emergency laparotomy for pneumoperitoneum caused by a gastric perforation. At 10 days after the surgery, he presented with bilateral scrotal swelling and ill-defined infiltrating lesions in both testicles. Ultrasound confirmed both patent processus vaginalis. Scrotal incision revealed a yellow mass attaching to both testicles, which was finally diagnosed as abscesses. This case highlights the importance of considering scrotal abscess as a potential complication following intestinal perforation and postoperative intraperitoneal infections in newborn infants.

Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996–2020

Background@#The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI). @*Methods@#A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed. @*Results@#A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (rs = −0.430, P = 0.036), H. influenzae (rs = −0.922, P 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

Erratum: Addition of a Co-Author: Etiology of Invasive Bacterial Infections in Immunocompetent Children in Korea (2006–2010): a Retrospective Multicenter Study

The authors regret that one co-author (Kyung-Hyo Kim) was missing in the article.

Clinical features and prognostic factors of early-onset sepsis: a 7.5-year experience in one neonatal intensive care unit / 소아과

PURPOSE: In this study, we investigated the clinical features and prognostic factors of early-onset sepsis (EOS) in neonatal intensive care unit (NICU) patients. METHODS: A retrospective analysis was conducted on medical records from January 2010 to June 2017 (7.5 years) of a university hospital NICU. RESULTS: There were 45 cases of EOS (1.2%) in 3,862 infants. The most common pathogen responsible for EOS was group B Streptococcus (GBS), implicated in 10 cases (22.2%), followed by Escherichia coli, implicated in 9 cases (20%). The frequency of gram-positive sepsis was higher in term than in preterm infants, whereas the rate of gram-negative infection was higher in preterm than in term infants (P < 0.05). The overall mortality was 37.8% (17 of 45), and 47% of deaths occurred within the first 3 days of infection. There were significant differences in terms of gestational age (26.8 weeks vs. 35.1 weeks) and birth weight (957 g vs. 2,520 g) between the death and survival groups. After adjustments based on the difference in gestational age and birth weight between the 2 groups, gram-negative pathogens (odds ratio [OR], 42; 95% confidence interval [CI], 1.4–1,281.8) and some clinical findings, such as neutropenia (OR, 46; 95% CI, 1.3–1,628.7) and decreased activity (OR, 34; 95% CI, 1.8–633.4), were found to be associated with fatality. CONCLUSION: The common pathogens found to be responsible for EOS in NICU patients are GBS and E. coli. Gram-negative bacterial infections, decreased activity in the early phase of infection, and neutropenia were associated with poor outcomes.

Lung Ultrasonography Score as a Respiratory Parameter of Respiratory Distress Syndrome in Very Preterm Infants: A Single Center Experience

PURPOSE: Comparison between lung ultrasound (LUS) score and indices of respiratory severity in very preterm infants born at 28 to 31 weeks' gestation. METHODS: We retrospectively reviewed medical records of 32 very preterm infants born at 28 to 31 weeks' gestation at Keimyung University Dongsan Medical Center. Before surfactant administration, bedside LUS in the neonatal intensive care unit was recorded within the first hour of life. Partial pressure of capillary oxygen to fraction of inspired oxygen ratio (PcO2)/FiO2, alveolar-arterial gradient (A-aO2), modified oxygenation index (OI), and arterial to alveolar ratio were calculated. Correlation between LUS score and indices of respiratory severity were analyzed between the intubation and nasal continuous positive airway pressure (NCPAP) groups depending on the presence or absence of endotracheal intubation. RESULTS: Mean LUS scores, A-aO2, and modified OI in the intubation group were significantly higher than those in the NCPAP group. Conversely, PcO2/FiO2 and arterial to alveolar ratios in the intubation group were significantly lower than those in the NCPAP group. LUS score was found to be significantly correlated with A-aO2 (r=0.448, P>0.05) and modified OI (r=0.453, P>0.05), but not with PcO2/FiO2 ratio (r=−0.205, P0.05). CONCLUSION: The LUS score is well correlated with indices of respiratory severity in very preterm infants born at 28 to 31 weeks' gestation. Further investigation is needed to use LUS as an alternative tool in infants with respiratory distress.

Etiology of Invasive Bacterial Infections in Immunocompetent Children in Korea (2006–2010): a Retrospective Multicenter Study

BACKGROUND: Invasive bacterial infections in apparently immunocompetent children were retrospectively analyzed to figure causative bacterial organisms in Korea. METHODS: A total of 947 cases from 25 university hospitals were identified from 2006 to 2010 as a continuance of a previous 10-year period study from 1996 to 2005. RESULTS: Escherichia coli (41.3%), Streptococcus agalactiae (27.7%), and Staphylococcus aureus (27.1%) were the most common pathogens in infants < 3 months of age. S. agalactiae was the most prevalent cause of meningitis and pneumonia and E. coli was the major cause of bacteremia without localizing signs in this group. In children 3 to 59 months of age, Streptococcus pneumoniae (54.2%), S. aureus (20.5%), and Salmonella spp. (14.4%) were the most common pathogens. S. pneumoniae was the leading cause of pneumonia (86.0%), meningitis (65.0%), and bacteremia without localizing signs (49.0%) in this group. In children ≥ 5 years of age, S. aureus (62.8%) was the predominant pathogen, followed by Salmonella species (12.4%) and S. pneumoniae (11.5%). Salmonella species (43.0%) was the most common cause of bacteremia without localizing signs in this group. The relative proportion of S. aureus increased significantly over the 15-year period (1996–2010) in children ≥ 3 months of age (P < 0.001), while that of Haemophilus influenzae decreased significantly in both < 3 months of age group (P = 0.036) and ≥ 3 months of age groups (P < 0.001). CONCLUSION: S. agalactiae, E. coli, S. pneumoniae, and S. aureus are common etiologic agents of invasive bacterial infections in Korean children.

Amino Acid-Based Formula in Premature Infants with Feeding Intolerance: Comparison of Fecal Calprotectin Level / 대한소아소화기영양학회지

PURPOSE: We investigated fecal calprotectin (FC) levels in preterm infants with and without feeding intolerance (FI), and compared the FC levels according to the type of feeding. METHODS: The medical records of 67 premature infants were reviewed retrospectively. The fully enteral-fed infants were classified into two groups; the FI group (29 infants) and the control group (31 infants). Seven infants with necrotizing enterocolitis, sepsis, and perinatal asphyxia were excluded. If breast milk (BM) or preterm formula (PF) could not be tolerated by infants with FI, amino acid-based formula (AAF) was tried temporarily. Once FI improved, AAF was discontinued, and BM or PF was resumed. We investigated the FC levels according to the type of feeding. RESULTS: Significant differences were found in gestational age, birth weight, age when full enteral feeding was achieved, and hospital stay between the FI and control group (p 0.05). CONCLUSION: The FC levels in AAF-fed infants with FI showed significantly lower than those in the BM- or PF-fed infants with FI. The mitigation of gut inflammation through the decrease of FC levels in AAF-fed infants with FI could be presumed.

Safety and Immunogenicity of an Egg-Cultivated Quadrivalent Inactivated Split-virion Influenza Vaccine (GC3110A) in Healthy Korean Children: a Randomized, Double-blinded, Active-controlled Phase III Study

BACKGROUND: The frequency with which the 2 B lineages have been found to cocirculate in a season has been on the rise, which has spurred the need for a quadrivalent influenza vaccine (QIV) to protect against both B lineages. The World Health Organization (WHO) recommended that QIV include both B lineages beginning in the 2013–2014 flu season. This study was conducted to evaluate the immunogenicity and safety of an egg-cultivated QIV in healthy Korean children and adolescents aged ≥ 6 months to < 19 years. METHODS: A total of 528 subjects were randomized 4:1 to receive either a QIV (GC3110A) or a trivalent influenza vaccine. Hemagglutination inhibition antibody responses were assessed 28 days after the last dose. Safety was also evaluated. RESULTS: The proportion of subjects in the GC3110A group who achieved seroconversion was confirmed to exceed 40% across all age groups. The proportion of subjects aged ≥ 6 months to < 3 years in the GC3110A group who achieved seroprotection failed to meet the Ministry of Food and Drug Safety (MFDS) standard of 70%. Potential causes may include the small number of subjects, as well as the small dosage. However, results pertaining to the other age groups satisfied the MFDS standard. The safety profile was also comparable to that of the control. CONCLUSION: The new quadrivalent split influenza vaccine may offer broader protection to children and adolescents aged ≥ 3 years to < 19 years of age against both influenza B lineages than the existing trivalent influenza vaccines (Registered at the ClinicalTrials.gov NCT02541253).

Neuroprotective effects of erythropoietin against hypoxic injury via modulation of the mitogen-activated protein kinase pathway and apoptosis / 소아과

PURPOSE: Hypoxic-ischemic encephalopathy is a significant cause of neonatal morbidity and mortality. Erythropoietin (EPO) is emerging as a therapeutic candidate for neuroprotection. Therefore, this study was designed to determine the neuroprotective role of recombinant human EPO (rHuEPO) and the possible mechanisms by which mitogen-activated protein kinase (MAPK) signaling pathway including extracellular signal-regulated kinase (ERK1/2), JNK, and p38 MAPK is modulated in cultured cortical neuronal cells and astrocytes. METHODS: Primary neuronal cells and astrocytes were prepared from cortices of ICR mouse embryos and divided into the normoxic, hypoxia (H), and hypoxia-pretreated with EPO (H+EPO) groups. The phosphorylation of MAPK pathway was quantified using western blot, and the apoptosis was assessed by caspase-3 measurement and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. RESULTS: All MAPK pathway signals were activated by hypoxia in the neuronal cells and astrocytes (P<0.05). In the neuronal cells, phosphorylation of ERK-1/-2 and apoptosis were significantly decreased in the H+EPO group at 15 hours after hypoxia (P<0.05). In the astrocytes, phosphorylation of ERK-1/-2, p38 MAPK, and apoptosis was reduced in the H+EPO group at 15 hours after hypoxia (P<0.05). CONCLUSION: Pretreatment with rHuEPO exerts neuroprotective effects against hypoxic injury reducing apoptosis by caspase-dependent mechanisms. Pathologic, persistent ERK activation after hypoxic injury may be attenuateed by pretreatment with EPO supporting that EPO may regulate apoptosis by affecting ERK pathways.

Lung Ultrasonography for the Diagnosis of Respiratory Distress Syndrome in Late Preterm Infants: Changing Incidence – A Single Center Experience

PURPOSE: Ultrasonography is non-ionizing, easy to operate, and performed at bedside in neonatal intensive care unit (NICU). We investigated the incidence of respiratory distress syndrome (RDS) with or without using lung ultrasound (LUS) in late preterm infants with postnatal respiratory difficulties. METHODS: We retrospectively reviewed medical records of 494 late preterm infants born at 34–36 weeks' gestation at Keimyung University Dongsan Medical Center. Fifty infants with postnatal respiratory difficulties were admitted to the NICU between May 2015 to October 2015 (period I), and forty-one were between November 2015 to February 2016 (period II). The diagnosis of RDS was based on chest radiography in period I. LUS was additionally performed at bedside in period II. All infants with RDS were received exogenous surfactant therapy. RESULTS: The overall incidence of RDS with surfactant replacement therapy was decreased in period II period II (9.4%, 20/212) compared to period I (14.5%, 41/282) (P=0.088). In terms of infants with postnatal respiratory difficulties, the incidence of RDS in period II (48.8%, 20/41) was significantly lower than that in period I (82.0%, 41/50) (P=0.001). There are no difference in the rate of reintubation, repeated doses of surfactant, oxygen demand at 48 hours after birth, air leak syndrome, pulmonary hemorrhage, persistent pulmonary hypertension of newborn, and mortality (P> 0.05). CONCLUSION: We could decrease the incidence of RDS with surfactant replacement therapy by using LUS in late preterm infants with postnatal respiratory difficulties. Further prospective studies are needed to apply LUS clinically to diagnose RDS.

Early Changes in the Serotype Distribution of Invasive Pneumococcal Isolates from Children after the Introduction of Extended-valent Pneumococcal Conjugate Vaccines in Korea, 2011-2013

This study was performed to measure early changes in the serotype distribution of pneumococci isolated from children with invasive disease during the 3-year period following the introduction of 10- and 13-valent pneumococcal conjugate vaccines (PCVs) in Korea. From January 2011 to December 2013 at 25 hospitals located throughout Korea, pneumococci were isolated among children who had invasive pneumococcal disease (IPD). Serotypes were determined using the Quellung reaction, and the change in serotype distribution was analyzed. Seventy-five cases of IPD were included. Eighty percent of patients were aged 3-59 months, and 32% had a comorbidity that increased the risk of pneumococcal infection. The most common serotypes were 19A (32.0%), 10A (8.0%), and 15C (6.7%). The PCV7 serotypes (4, 6B, 9V, 14, 18C, 19F, 23F, and 6A) accounted for 14.7% of the total isolates and the PCV13 minus PCV7 types (1, 3, 5, 7F and 19A) accounted for 32.0% of the total isolates. Serotype 19A was the only serotype in the PCV13 minus PCV7 group. The proportion of serotype 19A showed decreasing tendency from 37.5% in 2011 to 22.2% in 2013 (P = 0.309), while the proportion of non-PCV13 types showed increasing tendency from 45.8% in 2011 to 72.2% in 2013 (P = 0.108). Shortly after the introduction of extended-valent PCVs in Korea, serotype 19A continued to be the most common serotype causing IPD in children. Subsequently, the proportion of 19A decreased, and non-vaccine serotypes emerged as an important cause of IPD. The impact of extended-valent vaccines must be continuously monitored.

Insulin and glucagon levels of umbilical cord blood in appropriate for gestational age - preterm infants with or without postnatal hypoglycemia

PURPOSE: To determine whether serum insulin and glucagon levels of umbilical cord blood correlate with subsequent postnatal hypoglycemia in appropriate for gestational age (AGA) - preterm infants at different gestational ages (GAs). METHODS: The serum insulin and glucagon levels of umbilical cord blood were measured using magnetic bead based multiplex immunoassay in 69 AGA - premature infants, stratified according to GA: GA 23-30 weeks, early preterm (EP, n=31); GA 31-34 weeks, late preterm (LP, n=38). Postnatal hypoglycemia was defined as a capillary glucose level <40 mg/dL within the first 60 minutes of life, regardless of GA. RESULTS: The capillary glucose concentration in EP infants (65.5±21.2 mg/dL) was significantly higher than that of LP infants (55.9±17.3 mg/dL) (P=0.043). The serum glucagon level in EP infants (44.3±28.7 pg/mL) was significantly higher than that in LP infants (28.1±13.6 pg/mL) (P=0.006). There was not a significant difference in serum insulin level between EP and LP infants (372.7±254.2 pg/mL vs. 372.4±209.1 pg/mL, P=0.996). There was a significant difference in the serum glucagon level between infants with and without hypoglycemia (27.7±8.9 mg/dL vs. 36.8±24.6 mg/dL, P=0.036), but not in the serum insulin level (451.9±256.9 pg/mL vs. 357.4±222.2 pg/mL, P=0.211). Postnatal glucose concentration within the first 60 minutes of life had a significant positive correlation with serum glucagon levels (r=0.256, P=0.034), but not with serum insulin levels (r=-0.020, P=0.867). CONCLUSION: Lower glucagon levels of cord blood were seen in premature infants with higher GA, which might contribute to the occurrence of postnatal hypoglycemia.

Insulin and glucagon levels of umbilical cord blood in appropriate for gestational age - preterm infants with or without postnatal hypoglycemia

PURPOSE: To determine whether serum insulin and glucagon levels of umbilical cord blood correlate with subsequent postnatal hypoglycemia in appropriate for gestational age (AGA) - preterm infants at different gestational ages (GAs). METHODS: The serum insulin and glucagon levels of umbilical cord blood were measured using magnetic bead based multiplex immunoassay in 69 AGA - premature infants, stratified according to GA: GA 23-30 weeks, early preterm (EP, n=31); GA 31-34 weeks, late preterm (LP, n=38). Postnatal hypoglycemia was defined as a capillary glucose level <40 mg/dL within the first 60 minutes of life, regardless of GA. RESULTS: The capillary glucose concentration in EP infants (65.5±21.2 mg/dL) was significantly higher than that of LP infants (55.9±17.3 mg/dL) (P=0.043). The serum glucagon level in EP infants (44.3±28.7 pg/mL) was significantly higher than that in LP infants (28.1±13.6 pg/mL) (P=0.006). There was not a significant difference in serum insulin level between EP and LP infants (372.7±254.2 pg/mL vs. 372.4±209.1 pg/mL, P=0.996). There was a significant difference in the serum glucagon level between infants with and without hypoglycemia (27.7±8.9 mg/dL vs. 36.8±24.6 mg/dL, P=0.036), but not in the serum insulin level (451.9±256.9 pg/mL vs. 357.4±222.2 pg/mL, P=0.211). Postnatal glucose concentration within the first 60 minutes of life had a significant positive correlation with serum glucagon levels (r=0.256, P=0.034), but not with serum insulin levels (r=-0.020, P=0.867). CONCLUSION: Lower glucagon levels of cord blood were seen in premature infants with higher GA, which might contribute to the occurrence of postnatal hypoglycemia.

Temporary Transcutaneous Pacing in a Low Birth Weight Preterm Neonate with Congenital Complete Atrioventricular Block: A Case Report

Congenital complete atrioventricular (AV) block is a rare neonatal disease. It is a passively acquired immune-mediated injury of the conduction system, triggered by transplacental passage of maternal anti-SSA/Ro and anti-SSB/La antibodies. Management of premature infants with symptomatic complete AV block is challenging. If medical treatment with a β-adrenergic agonist and inotropic drugs is not effective, early cardiac pacing should be considered. Here we report a case of congenital complete AV block in a low birth weight, preterm neonate, who was successfully treated with temporary transcutaneous pacing immediately after birth. Temporary transcutaneous pacing may be an option for the emergent management of a low birth weight preterm neonate with congenital complete AV block prior to permanent pacemaker implantation.

Pulmonary Outcomes of Early Extubation in Extremely Premature Infants (Gestational Age: 25-26 Weeks) with Synchronized Nasal Intermittent Positive-Pressure Ventilation

PURPOSE: To investigate the pulmonary outcomes of early extubation (within the first 24 hours of life) with synchronized nasal intermittent positive pressure ventilation (NIPPV) in extremely premature infants born at 25-26 weeks' gestation. METHODS: Medical records of extremely premature infants (gestational age: 25-26 weeks) born and admitted to the Keimyung University Dongsan Medical Center between January 2015 and December 2015 (n=42) were reviewed retrospectively. The early extubation group included infants who were extubated within the first 24 hours of life and was compared with a control group that included infants who remained ventilated beyond the first 24 hours of life. Extubation failure was defined as the need for reintubation within 72 hours after extubation. RESULTS: Of the 35 enrolled infants, 22 (62.9%) were extubated within the first 24 hours of life. No significant differences in perinatal factors were observed between the early extubation and control groups. Between the two groups, the incidence rates of extubation failure (18.2% [4/22] vs. 7.7% [1/13], P=0.39), reintubation (50.0% [11/ 22] vs. 46.2% [6/13], P=0.84), mortality (18.2% [4/22] vs. 15.4% [2/13], P=0.83), and the combined rates of clinical bronchopulmonary dysplasia (BPD) or death (40.9% [9/22] vs. 38.5% [5/13], P=0.89) did not significantly differ. CONCLUSION: Early extubation (within the first 24 hours of life) with synchronized NIPPV is safe and effective in the extremely premature infants born at 25-26 weeks' gestation, and does not indicate increased risks of extubation failure and other morbidities.

Clinical Findings According to Feeding Diets in Very Low Birth Weight Infants: Human Breast Milk versus Bovine Milk-Based Formula

PURPOSE: We aimed to compare the clinical findings, including morbidity, duration of parenteral nutrition, and length of hospital stay between very low birth weight infants (VLBWIs) fed bovine milk-based formula (BOV) and VLBWIs fed human breast milk (HBM) in a neonatal intensive care unit (NICU). METHODS: VLBWIs admitted to the NICU of Dongsan Medical Center, Keimyung University, were enrolled. Infants born from March to August 2014 (n=28) were fed BOV (the BOV group), and those born from September to December 2014 (n=18) were fed HBM (the HBM group). Pasteurized (heating at 62.5degrees C for 30 minutes) donor human milk was used if the mother's own milk was not available because of insufficient breast milk production. RESULTS: The gestational age (28.0+/-1.7 weeks vs. 27.8+/-1.4 weeks) and birth weight (1,055+/-265 g vs. 1,175+/-187 g), of the infants in the BOV and HBM, groups were similar. In addition, perinatal characteristics were similar between the groups. The duration of parenteral nutrition (36.4 days vs. 24.1 days, P=0.038), length of hospital stay (74.3 days vs.61.1 days, P=0.037), and incidence of nosocomial sepsis (53.6% vs. 22.2%, P=0.035), significantly differed between the BOV and HBM groups. Furthermore, the frequency of feeding intolerance was higher in the BOV group than in the HBM group, but this difference was not significant. Perinatal cytomegalovirus infection was not detected in any of the infants fed pasteurized donor human milk. CONCLUSION: Human-breast-milk-based diet for VLBWIs significantly reduces the incidence of nosocomial sepsis, duration of parenteral nutrition, and length of hospital stay.

Respiratory Syncytial Virus Related Readmission in Preterm Infants Less than 34 weeks' Gestation Following Discharge from a Neonatal Intensive Care Unit in Korea

This study was done to evaluate respiratory syncytial virus (RSV) related readmission (RRR) and risk factors of RRR in preterm infants 1 yr after discharge from the NICU, were enrolled. The average GA and birth weight of the infants was 30(+5) +/- 2(+5) weeks and 1,502 +/- 474 g, respectively. The RRR rate of enrolled infants was 8.4% (96/1,140), and RSV accounted for 58.2% of respiratory readmissions of infants who had laboratory tests confirming etiological viruses. Living with elder siblings (odd ratio [OR], 2.68; 95% confidence interval [CI], 1.68-4.28; P < 0.001), and bronchopulmonary dysplasia (BPD) (OR, 2.95; 95% CI, 1.44-6.04; P = 0.003, BPD vs. none) increased the risk of RRR. Palivizumab prophylaxis (OR, 0.06; 95% CI, 0.03-0.13; P < 0.001) decreased the risk of RRR. The risk of RRR of infants of 32-33 weeks' gestation was lower than that of infants < 26 weeks' gestation (OR, 0.11; 95% CI, 0.02-0.53; P = 0.006). This was a nationwide study that evaluated the rate and associated risk factors of RRR in Korean preterm infants. Preterm infants with BPD or living with siblings should be supervised, and administration of palivizumab to prevent RRR should be considered.

Early-onset Pericardial Effusion after Peripherally Inserted Central Venous Catheterization in a Preterm Infant / 대한주산의학회잡지

Peripherally inserted central venous catheters (PICC) are commonly used to provide long term intravascular access for parenteral nutrition and medications in preterm infants, but rarely life-threatening complications associated with malposition of catheter tip such as pericardial effusion may be developed. We report a preterm case of early-onset pericardial effusion related to PICC of which the distal part is angulated and located in the right atrium of heart.

The Effect of Combination Treatment of Melatonin and Hypothermia on Hypoxic-Ischemic Brain Injury in Neonatal Rats

PURPOSE: Melatonin is a naturally occurring hormone produced by the pineal gland. Melatonin has many pharmacological effects in different tissues or organs. Melatonin is especially known to have antioxidant and neuroprotective effects. Hypothermia is a therapeutic tool against hypoxia-ischemia (HI) of the brain. This study examines the effect of combined therapy using melatonin and hypothermia in neonatal rats with HI. METHODS: Seven-day old rats were subjected to HI and randomized into four groups : vehicle, melatonin alone, vehicle and hypothermia, and melatonin and hypothermia. Melatonin (30 mg/kg) was intraperitoneally administered in two doses: immediately following HI, and 24 h later. Hypothermia consisted of whole-body cooling (3 hours, 27degrees C). Sham-treated animals not subjected to HI were also studied. P10, P14, and P35 rats were sacrificed for experiments. RESULTS: Vehicle-treated P10 rats increased in brain infarction compared to controls in TTC staining study. And also, P35 rats decreased in brain volume of injured hemisphere in H&E stain. Melatonin or hypothermia alone did not show any protective effect against HI. However, a combination of melatonin and hypothermia effectively reduced the brain injury. In addition, the results of in situ zymography, TUNEL assay and immunofluorescence studies showed that neuroprotective effects were achieved only with combined therapy. CONCLUSION: Melatonin may contribute to synergistic effects to neuroprotection of hypothermia on brain damage after HI.

The Readmission of Preterm Infants of 30-33 Weeks Gestational Age within 1 Year Following Discharge from Neonatal Intensive Care Unit in Korea

PURPOSE: This study was conducted to evaluate the readmission rate of preterm infants of 30-33 weeks gestational age (GA) within 1 year following discharge from the neonatal intensive care unit (NICU). METHODS: This research was a part of the Retrospective Study to Evaluate Rehospitalization & Health Care Utilization after NICU Discharge in Preterm Infants (< or =33 weeks) II (RHANPI II) project conducted by the Committee on Data Collection and Statistical Analysis of the Korean Society of Neonatology. Enrolled infants (n=1,257) of 46 hospitals from April to September 2012, were retrospectively studied. RESULTS: The average GA and birth weight of the study population was 32(+2)+/-1(+1) weeks and 1,785+/-386 g, respectively. The cumulative readmission rate during the 360 days following discharge from the NICU was 27.3%. The cumulative readmission rate according to GA was 36.4%, 30.1%, 25.9% and 22.7% for infants born at 30, 31, 32 and 33 weeks GA, respectively. The corresponding respiratory readmission rate was 16.3%; this was 59.8% of total readmissions. There was no significant difference in the respiratory readmission rate according to GA group (log-rank test for trend, P-value=0.0558). Of the infants who were readmitted with respiratory problems, 57.0% (n=53/93) tested positive for respiratory syncytial virus (RSV). CONCLUSION: The cumulative readmission rate during the 360 days following discharge from the NICU was 27.3%. Respiratory problems were the most common cause of readmission, and RSV was the most common virus associated with respiratory readmission. Additionally, there was no difference in the rate of respiratory readmission according to GA group.