Byong Sop Lee

University of Ulsan, Ulsan, Ulsan, South Korea

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Publications (48)62.62 Total impact

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    Byong Sop Lee · Wi Hwan Moon · Eun Ae Park
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    ABSTRACT: Real-time data reporting in clinical research networks can provide network members through interim analyses of the registered data, which can facilitate further studies and quality improvement activities. The aim of this report was to describe the building process of the data display system (DDS) of the Korean Neonatal Network (KNN) and its basic structure. After member verification at the KNN member's site, users can choose a variable of interest that is listed in the in-hospital data statistics (for 90 variables) or in the follow-up data statistics (for 54 variables). The statistical results of the outcome variables are displayed on the HyperText Markup Language 5-based chart graphs and tables. Participating hospitals can compare their performance to those of KNN as a whole and identify the trends over time. Ranking of each participating hospital is also displayed in terms of key outcome variables such as mortality and major neonatal morbidities with the names of other centers blinded. The most powerful function of the DDS is the ability to perform 'conditional filtering' which allows users to exclusively review the records of interest. Further collaboration is needed to upgrade the DDS to a more sophisticated analytical system and to provide a more user-friendly interface.
    Preview · Article · Nov 2015 · Journal of Korean medical science
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    Preview · Article · Sep 2015 · Annals of Laboratory Medicine
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    ABSTRACT: This study aimed to evaluate the validity of the ages and stages questionnaire in Korean (ASQ 1st edition, Korean Questionnaires, Seoul Community Rehabilitation Center, 2000) for premature infants. The study population consisted of 90 premature infants born between January 1, 2005, and December 31, 2011, who were tested using the ASQ (Korean) and Bayley Scales of Infant Development (BSID) (II) at a corrected age of 18-24 months. The validity of the ASQ (Korean) using cut-off values set at < -2 SD was examined by comparing it to the BSID (II) components, namely, the mental developmental index (MDI) or psychomotor developmental index (PDI), which were both set at < 85. The calculation of the sensitivities, specificities, positive predictive values, and negative predictive values of the ASQ (Korean) components revealed that they detected infants with neurodevelopmental delay with low sensitivity and positive predictive values, however, the communication domain showed moderate correlations with MDI. The failure in more than one domain of the ASQ (Korean) was significantly correlated with the failure in MDI. The ASQ (Korean) showed low validity for screening neurodevelopmentally delayed premature infants. Graphical Abstract
    Full-text · Article · Apr 2015 · Journal of Korean medical science
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    ABSTRACT: Hypernatremic dehydration is an important cause of intracranial hemorrhage. A possible association of intraventricular hemorrhage (IVH) with hypernatremia and/or high sodium intake has been suggested in preterm infants. To investigate the associations of early fluid and sodium intake or serum sodium concentrations with severe intraventricular hemorrhage (IVH) in extremely low birth weight (ELBW) infants, we reviewed the medical records of 169 inborn ELBW infants. Daily fluid and sodium intake, urine output, weight loss and serum sodium concentration during the first 4 days of life were obtained. Patients were divided into the severe IVH (grade 3/4) and the control (no or grade 1/2 IVH) group. The maximum serum sodium concentration and the incidence of hypernatremia did not differ between the two groups. Related to the fluid balance and sodium intake, the risk for severe IVH was strongly associated with total fluid and sodium intake during the initial four days of life. With respect to the fluids other than transfusion, severe IVH can be discriminated only by sodium intake but not by fluid intake. Large randomized controlled trials are required to clarify the causal relationship between the early sodium intake and severe IVH in ELBW infants. Graphical Abstract
    Full-text · Article · Mar 2015 · Journal of Korean Medical Science
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    Byong Sop Lee
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    ABSTRACT: Relative to a fetus of the same gestational age, very low birth weight (VLBW) infants are more likely to be underfed and to undergo growth restriction during their early hospital stay. The current trend towards "early and aggressive" nutritional strategies in VLBW infants aims to overcome the early nutritional deficiency and thereby boost postnatal catch-up growth, simultaneously improving long-term neurodevelopmental outcomes. Although the minimum starting amino acid (AA) dose to prevent negative nitrogen balance is well established, the upper limit and the rate of increase of early AA doses are controversial. Most randomized controlled trials show that early and high-dose (target, 3.5 to 4.9 g/kg/day) AA regimens, with or without high nonprotein calories, do not improve long-term growth and neurodevelopment. High-dose AA supplementation may lead to early metabolic disturbances and excessive or disproportionate plasma AA levels, particularly in infants of very low gestational age. Further large studies are needed to clarify the optimal strategy for early administration of parenteral AA doses in VLBW infants.
    Preview · Article · Mar 2015 · Korean Journal of Pediatrics
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    ABSTRACT: Abstract Objective: To observe central venous pressure (CVP) and to address the association with hemodynamic and renal parameters in very low birth weight infants (VLBWI) during the early neonatal period. Methods: CVP levels were prospectively measured every 4 h in VLBWI with an umbilical venous catheter for at least the initial 5 d of life. The association of CVP with mean blood pressure, serum B-type natriuretic peptide, serum creatinine, fluid intake, and urine output were analyzed. Results: In 25 infants, the mean daily CVP (mCVP) value of 3.5 ± 2.2 mmHg did not change between day 1 and day 7 after birth. There were no significant correlations between mCVP and mean blood pressure, serum BNP, serum creatinine, fluid intake, and urine output over the total study period. However, the mCVP was significantly correlated with urine output and serum creatinine 96-144 h after birth. Conclusions: After the transitional period, mCVP values were associated with renal function parameters in VLBWI.
    No preview · Article · Jan 2015 · Journal of Maternal-Fetal and Neonatal Medicine
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    ABSTRACT: To determine whether serum uric acid levels in the first 7 days of life can predict development of severe intraventricular hemorrhage (IVH) among very low birth weight (VLBW) infants.
    Preview · Article · Jan 2015
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    ABSTRACT: To investigate the relationship between placental pathology and neurodevelopmental outcomes among extremely low birth weight (ELBW) infants.
    Preview · Article · Jan 2015
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    Byong Sop Lee
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    ABSTRACT: An abnormal plasma glucose concentration is one of the most commonly encountered metabolic problems in the intensive care of premature infants. Compared with term infants, glycogen reserves are lower in the preterm neonatal liver. Despite this, preterm infants are at a greater risk of hyperglycemia than term infants are, which is owing to comparable production rate of endogenous glucose and impaired ability to reduce glucose production rate in response to hyperglycemia. Debate continues about the normal plasma glucose concentrations and the guideline for glucose control in premature infants. Some randomized controlled trials in very low birth weight infants demonstrated little clinical benefit of tight glycemic control with early insulin therapy and higher calorie intake in terms of mortality, morbidities and growth parameters. Compared with term infants, preterm infants have limited endocrine and metabolic adaptation to hypoglycemia. In any case, hypoglycemia in premature infants should not be considered a physiologic condition. The operational criteria for intervention of hypoglycemia should be different from that in term infants. Continuous non-invasive glucose monitoring is a promising tool considering the principle of minimal handling of extremely premature infants. However, the clinical implication of abnormal glucose concentrations, previously undetected on intermittent measurements, is unclear.
    Preview · Article · Jan 2015
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    ABSTRACT: Background: It remains unclear whether the benefit of postnatal corticosteroid as a respiratory rescue therapy outweighs the potential harm of neurodevelopmental impairment (NDI) in very-low-birth-weight infants at risk of bronchopulmonary dysplasia (BPD). Methods: We reviewed the charts of very-low-birth-weight infants with oxygen dependency for 28 days or more and who survived until 18-22 months' corrected age. Patients were divided into the delayed (≥21 days after birth) dexamethasone therapy (DDT, n=71) and the control (n=60) groups. NDI was defined by the presence of cerebral palsy, Bayley Mental or Psychomotor Developmental Index less than 70, deafness, or blindness. Results: The DDT group was more premature and had worse respiratory morbidities before (ventilator-dependent at 21 days, 69% vs. 17%) and after the DDT (moderate/severe BPD, 41% vs. 15%) than the control group. The risk of NDI did not differ between the DDT and the control groups in the entire cohort (odds ratio and 95% confidence interval, 1.309 [0.530-3.237]) or in the propensity-score-matched cohort (n=62; odds ratio and 95% confidence interval, 1.344 [0.455-3.976]). However, in the subgroup of infants exposed to DDT, the cumulative dexamethasone dose greater than 5.0 mg/kg was significantly associated with NDI. Conclusion: Among the very-low-birth-weight infants with BPD, there was no definitely harmful effect of DDT on the neurodevelopmental outcome in the short term. However, considering the potential harm of high cumulative doses of dexamethasone on the developing brain, further studies are needed to determine the optimal dosage of DDT to be administered for the prevention of BPD.
    No preview · Article · Dec 2014 · Pediatrics & Neonatology
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    ABSTRACT: Objective To report our experiences in the prenatal diagnosis of atrial isomerism and postnatal outcomes. Methods A total of 80 fetuses prenatally diagnosed with atrial isomerism were retrospectively analyzed between 1999 and 2011 at a single institution. Results Of 43 fetuses with prenatally diagnosed right atrial isomerism (RAI), 40 cases were analyzed. The diagnostic accuracy was 93%. The main intracardiac anomalies in RAI were atrioventricular septal defect (AVSD), abnormal pulmonary venous connection, bilateral superior vena cava (BSVC), and pulmonary atresia. Among 28 live births, three infants were lost to follow up, and the overall survival rate was 60%. Of 37 fetuses with prenatally diagnosed left atrial isomerism (LAI), 35 were evaluated. The diagnostic accuracy was 97%. The main intracardiac anomalies in LAI were ventricular septal defect, BSVC, AVSD, double outlet right ventricle, and bradyarrhythmia. Among seven patients with bradyarrhythmia, only one showed a complete atrioventricular block. All fetuses had an interrupted inferior vena cava with azygous continuation. The overall survival rate was 90%. Conclusion Our study confirms the previous findings of fetal atrial isomerism. We also demonstrates a much lower prevalence of AVSD and complete heart block in LAI and a better survival rate in RAI. Although the postnatal outcomes for RAI were worse than those for LAI, successful postnatal surgery with active management improved the survival rate.
    Full-text · Article · May 2014
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    ABSTRACT: Continuous renal replacement therapy (CRRT) has become an essential modality for the care of critically ill pediatric patients who require renal support. However, experience with CRRT in the neonatal population is not common in Korea. In this study, we aimed to investigate the clinical features, outcomes, and complications of CRRT in neonates in a single neonatal intensive care unit (NICU).
    Preview · Article · Jan 2014
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    ABSTRACT: Advances in neonatal intensive care have improved the chances for survival of extremely low birth weight (ELBW) infants. However, ELBW infants are at high risk of meningitis and resulting neurologic complications. The most common organisms associated with neonatal bacterial meningitis include Listeria monocytogenes, Escherichia coli, and Group B Streptococcus. Bacillus cereus (B. cereus), an organism commonly found in soil, vegetation, and daily products, can sometimes cause meningitis owing to preformed toxins. We report a rare case of meningoencephalitis caused by B. cereus that resulted in a detrimental neurological outcome in an ELBW infant.
    Preview · Article · Jan 2014
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    ABSTRACT: Introduction: To report our experience in fetuses prenatally diagnosed with common arterial trunk (CAT) and to evaluate the postnatal outcomes. Material and methods: This was a retrospective study conducted at Asan Medical Center, Seoul, Korea, between 2003 and 2012. Maternal medical and fetal echocardiographic records regarding fetuses were prenatally diagnosed with CAT were reviewed. Postnatal outcomes of survivors were also assessed during the mean follow-up of 36 months. Results: Of the 17 fetuses that were prenatally diagnosed with CAT and had a final diagnosis by postnatal echocardiography or autopsy, 12 were confirmed to have CAT and 5 were incorrectly diagnosed with CAT. Of the latter, 3 had pulmonary atresia and 2 had aortic atresia. The diagnostic accuracy was 71%. The median gestational age at prenatal diagnosis of confirmed CAT was 24.4 weeks (range 21.1-34.3). The truncal valve was prenatally thickened in 8 fetuses. All but 1 of the 12 confirmed CAT cases had associated heart and/or extracardiac anomalies. Of the 8 liveborn cases of postnatally confirmed CAT, 2 died before or after surgery respectively. The remaining 6 remained alive after successful corrective surgery. Conclusion: Prenatal diagnosis of CAT can be difficult in some cases and other diseases should be excluded before diagnosing CAT. Isolated CAT can be repaired by postnatal corrective surgery with a good outcome.
    No preview · Article · Sep 2013 · Fetal Diagnosis and Therapy
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    ABSTRACT: The aims of this study were to investigate whether early arterial blood gas analysis (ABGA) could define the severity of disease in infants with congenital diaphragmatic hernia (CDH). We conducted a retrospective study over a 21-yr period of infants diagnosed with CDH. Outcomes were defined as death before discharge, and extracorporeal membrane oxygenation requirements (ECMO) or death. A total 114 infants were included in this study. We investigated whether simplified prediction formula [PO2-PCO2] values at 0, 4, 8, and 12 hr after birth were associated with mortality, and ECMO or death. The area under curve (AUC) of receiver operating characteristic curve was used to determine the optimum ABGA values for predicting outcomes. The value of [PO2-PCO2] at birth was the best predictor of mortality (AUC 0.803, P < 0.001) and at 4 hr after birth was the most reliable predictor of ECMO or death (AUC 0.777, P < 0.001). The value of [PO2-PCO2] from ABGA early period after birth can reliably predict outcomes in infants with CDH.
    Full-text · Article · Jun 2013 · Journal of Korean medical science
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    ABSTRACT: Ebstein's anomaly is frequently detected before birth, with prenatal detection accounting for the majority of cases in the current population. This study aimed to identify the outcome variables among these infants. The medical records of 59 patients with neonatal Ebstein's anomaly managed at the Asan Medical Center between January, 2001 and June, 2012 were investigated retrospectively. In 46 cases, the diagnosis was made prenatally. Surgical/interventional procedures were performed for 27 of the analyzed patients. Biventricular repair was successful for 12 patients but not for 9 patients with pulmonary atresia. The median follow-up period was 1.96 years (range 0.0-10.4 years). The overall mortality rate was 23.7 % (14/59). Of the 14 deaths, 5 occurred within several hours after birth. The 1- and 5-year survival rates were 78.6 and 76.3 %, respectively. Univariate analysis identified several variables related to the time to death: fetal distress (p = 0.002), prematurity (p = 0.036), low birth weight (p = 0.003), diameter of the atrial septal defect (p = 0.022), and pulmonary stenosis/atresia (p = 0.001). Neither the Carpentier classification (p = 0.175) nor the Celermajer index (p = 0.958) was a significant variable. According to the multivariate analysis, fetal distress (p = 0.004) and pulmonary atresia/stenosis (p < 0.001) were significant determinants of outcome. In conclusion, fetal distress and pulmonary atresia/stenosis are significant predictors of mortality in the current population of patients with neonatal Ebstein's anomaly. A close cooperation of associated clinicians is required for an improvement in outcome. To establish a better surgical strategy for patients with Ebstein's anomaly and pulmonary atresia, studies of larger populations are required.
    No preview · Article · Mar 2013 · Pediatric Cardiology
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    ABSTRACT: Non-immune hydrops fetalis is the most severe presenting feature of lysosomal storage disorders. However, it is difficult to identify the underlying condition because the different lysosomal storage diseases share many clinical features. A neonate with hydrops fetalis is described here. A lysosomal storage disorder was first suspected when the placental biopsy showed the presence of macrophages containing numerous cytoplasmic vacuoles. Subsequent comprehensive diagnostic processes and biochemical and molecular genetics characterization revealed a rare genetic cause, namely sialidosis type 2. Liquid chromatography-mass spectrometry revealed increased amounts of bound sialic acid in the urine. Pathogenic NEU1 mutations were detected. This is the first case with sialidosis type 2 ever known in the Korean population, exhibiting its most severe manifestation.
    No preview · Article · Feb 2013 · Brain & development
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    ABSTRACT: Abstract Background: Thyroid dysfunction is very common and is associated with neurodevelopmental impairments in preterm infants. Objectives: This study was conducted to determine the incidence and natural course of various thyroid dysfunctions and their impacts on neurodevelopmental outcomes among premature infants. Methods: A total of 177 infants were enrolled who were born at <34 weeks or whose birth weight was <1500 g and who underwent repeat thyroid function tests. We analyzed how various thyroid dysfunctions affected neurodevelopmental outcomes at 18 months of corrected age. Results: Thyroid dysfunction was noted in 88 infants. Hypothyroxinemia was observed in 23 infants, and their thyroid function was influenced by variable clinical factors. Free T4 levels were all normalized without thyroxine medication, and neurodevelopmental outcomes were not affected. In contrast, hyperthyrotropinemia was not associated with other clinical factors. Among 58 subjects who had hyperthyrotropinemia, only 31 infants showed normal thyroid-stimulating hormone (TSH) levels at follow-up tests. The remaining 27 infants had persistently high TSH levels, which significantly and poorly influenced the neurodevelopmental outcomes. Conclusions: Thyroid dysfunction is common among preterm infants. With the exception of persistent hyperthyrotropinemia, it generally does not affect neurodevelopmental outcomes. However, the beneficial effects of thyroid hormone therapy in patients with persistent hyperthyrotropinemia merits further study.
    Full-text · Article · Feb 2013 · Journal of pediatric endocrinology & metabolism: JPEM
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    ABSTRACT: To assess the clinical features, hearing loss and neurodevelopmental outcomes of infants with congenital cytomegalovirus (CMV) infection and to discover significant brain magnetic resonance imaging (MRI) findings that predict poor neurodevelopmental outcomes.
    Full-text · Article · Jan 2013
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    Byong Sop Lee
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    ABSTRACT: Continuous renal replacement therapy (CRRT) is one of the hemofiltration-based dialysis modalities used in the management of the high risk neonates with acute renal failure, multi-organ dysfunction and inborn errors of metabolism. While there are different types of CRRT (hemodialysis, hemofiltration or both) used in critically ill patients, there is no consensus on the best type or target ultrafiltration dose of CRRT. In the neonates with hyperammonemia secondary to inborn errors of metabolism, CRRT is more efficient in lowering the plasma ammonia concentration than peritoneal dialysis, although no studies have clearly demonstrated the benefits in decreasing the mortality or the long-term neurodevelopmental morbidities. In neonatal care, the role of CRRT as a primary renal replacement therapy is limited by the difficulties in vascular access, bleeding complications and the lack of neonate-specific hemofiltration devices. Currently, neonatal CRRT in Korea is available only in a few large centers, mostly located in Seoul. The nationwide support for the establishment of the patient referral system and the securing of the personnel who are highly experienced in neonatal CRRT may contribute to improving the quality of neonatal care in Korea.
    Preview · Article · Jan 2013

Publication Stats

294 Citations
62.62 Total Impact Points

Institutions

  • 2009-2015
    • University of Ulsan
      • • Department of Pediatrics
      • • College of Medicine
      Ulsan, Ulsan, South Korea
  • 2010-2014
    • Asan Medical Center
      • • Department of Pediatrics
      • • Children's Hospital
      Sŏul, Seoul, South Korea
  • 2007-2012
    • Ulsan University Hospital
      Urusan, Ulsan, South Korea
  • 2002-2007
    • Seoul National University Hospital
      Sŏul, Seoul, South Korea
  • 2001
    • Seoul National University
      • Department of Pediatrics
      Sŏul, Seoul, South Korea