Soon Ju Lee

Polymorphisms of Human Leukocyte Antigen Genes in Korean Children with Kawasaki Disease

BackgroundKawasaki disease is a leading cause of acquired heart disease in children. The prevalence rate varies in different ethnic groups. Recently, with the clinical application of molecular genetic technology, human leukocyte antigen (HLA) polymorphisms associated with several diseases have been identified by DNA analysis. This study aimed to assess the association of HLA alleles with susceptibility and complications of Kawasaki disease in Korean children.MethodsIn this study, DNA was extracted from 74 children with a diagnosis of Kawasaki disease. The polymorphisms of the HLA-A, -B, -C, and -DRB1 alleles of patients with Kawasaki disease were determined by polymerase chain reaction (PCR)–amplification refractory mutation system (ARMS) and PCR–sequence-specific primer (SSP) analysis. The polymorphisms identified were compared with those of 159 normal healthy control subjects.ResultsThere was a significant increase in the frequencies of the HLA-B35, -B75, and -Cw09 alleles in patients with Kawasaki disease compared with the healthy control group. There was no increase in the frequency of HLA-DRB1 alleles among the Kawasaki disease patients compared with a healthy control group. When the patients with Kawasaki disease were divided into two subgroups, with or without coronary complications, the Kawasaki disease patients with coronary complications showed a significantly increased frequency of the HLA-DRB1*11 allele compared with the healthy control group and increased frequency of HLA-DRB1*09 in a comparison of the subgroups.ConclusionsThis study suggests that polymorphisms in some alleles of B and C in HLA class I genes are associated with Kawasaki disease in Korean children.

The genotype and clinical phenotype of Korean patients with familial hypokalemic periodic paralysis.

Familial hypokalemic periodic paralysis (HOPP) is a rare autosomal-dominant disease characterized by reversible attacks of muscle weakness occurring with episodic hypokalemia. Mutations in the skeletal muscle calcium (CACNA1S) and sodium channel (SCN4A) genes have been reported to be responsible for familial HOPP. Fifty-one HOPP patients from 20 Korean families were studied to determine the relative frequency of the known mutations and to specify the clinical features associated with the identified mutations. DNA analysis identified known mutations in 12 families: 9 (75%) were linked to the CACNA1S gene and 3 (25%) to the SCN4A gene. The Arg528His mutation in the CACNA1S gene was found to be predominant in these 12 families. Additionally, we have detected one novel silent exonic mutation (1950C>T) in the SCN4A gene. As for a SCN4A Arg669His mutation, incomplete penetrance in a woman was observed. Characteristic clinical features were observed both in patients with and without mutations. This study presents comprehensive data on the genotype and phenotype of Korean families with HOPP.

Two Cases of Cerebral Salt Wasting Syndrome Developing after Cranial Vault Remodeling in Craniosynostosis Children

Hyponatremia has been recognized as an important postoperative metabolic complication after central nervous system (CNS) operations in children. If not appropriately treated, the postoperative hyponatremia can cause several types of CNS and circulatory disorders such as cerebral edema, increased intracranial pressure. The postoperative hyponatremia after CNS surgery has been considered as one of the underlying causes of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). In some cases, however, the cerebral salt wasting (CSW) syndrome has been detected. CSW syndrome is far less well-known than SIADH and also different from SIADH in diagnosis and treatment. It causes an increase in urine output and urine sodium after a trauma of CNS and dehydration symptoms. The appropriate treatment of CSW syndrome is opposite the usual treatment of hyponatremia caused by SIADH. The latter is treated with fluid restriction because of the increased level of free water and its dilutional effect causing hyponatremia, whereas the former is treated with fluid and sodium resuscitation because of the unusual loss of high urinary sodium. Early diagnosis and treatment of CSW syndrome after CNS surgery are, therefore, essential. We made a diagnosis of CSW syndrome in two craniosynostosis children manifesting postoperative hyponatremia and supplied them an appropriate amount of water and sodium via intravenous route. The hyponatremia or natricuresis of the children improved and neurologic and circulatory sequelae could be prevented.

Normal Left Ventricular Torsion Mechanics in Healthy Children: Age Related Changes of Torsion Parameters Are Closely Related to Changes in Heart Rate

Background and Objectives This study was aimed at assessing left ventricular torsion (LVtor) mechanics using speckle tracking echocardiography (STE), establishing normal reference values of principal LVtor parameters, and analyzing the age-related changes in normal children. Subjects and Methods Eighty children (aged 3 months to 15 years) with normal cardiac function and rhythm were recruited. LVtor parameters including rotations, twist and untwist, torsion, and their rate indices were measured using STE. Age and heart rate related changes of the parameters were analyzed. Results Speckle tracking echocardiography analyses for LVtor parameters had excellent reliability in 64 of 80 subjects (80%) (intraclass correlation coefficients; 0.93-0.97). Early systolic twist (EST) motions (-8.4--0.1°) were observed in all subjects during an early 20±7% of systolic time intervals. The peak systolic twist and torsion were 17.0±6.5° and 2.9±1.3°/cm, respectively. The peak twist velocity was recorded at 51±13% of systolic time and the peak untwist velocity at 13.8±11.5% of diastolic time intervals. Multivariate analysis showed that heart rate change was an independent predictor of changes in torsion parameters; significantly decreasing LV length-normalized apical and basal rotation, torsion, and twist and untwist rate with increasing age. Isovolumetric recoil rate was independent of change in age and heart rate. Conclusion Left ventricle showed unique torsion mechanics in children with EST, torsion, and untwists. Heart rate was an independent predictor of the change in torsion parameters with aging.

Baseline heart rate variability in children and adolescents with vasovagal syncope.

Purpose This study aimed to evaluate the autonomic imbalance in syncope by comparing the baseline heart rate variability (HRV) between healthy children and those with vasovagal syncope. Methods To characterize the autonomic profile in children experiencing vasovagal syncope, we evaluated the HRV of 23 patients aged 7-18 years and 20 healthy children. These children were divided into preadolescent (<12 years) and adolescent groups. The following time-domain indices were calculated: root mean square of the successive differences (RMSSD); standard deviation of all average R-R intervals (SDNN); and frequency domain indices including high frequency (HF), low frequency (LF), normalized high frequency, normalized low frequency, and low frequency to high frequency ratio (LF/HF). Results HRV values were significantly different between healthy children and those with syncope. Student t test indicated significantly higher SNDD values (60.46 ms vs. 37.42 ms, P=0.003) and RMSSD (57.90 ms vs. 26.92 ms, P=0.000) in the patient group than in the control group. In the patient group, RMSSD (80.41 ms vs. 45.89 ms, P=0.015) and normalized HF (61.18 ms vs. 43.19 ms, P=0.022) were significantly higher in adolescents, whereas normalized LF (38.81 ms vs. 56.76 ms, P=0.022) and LF/HF ratio (0.76 vs. 1.89, P=0.041) were significantly lower in adolescents. In contrast, the control group did not have significant differences in HRV values between adolescents and preadolescents. Conclusion The results of this study indicated that children with syncope had a decreased sympathetic tone and increased vagal tone compared to healthy children. Additionally, more severe autonomic imbalances possibly occur in adolescents than in preadolescents.

Cytogenetic analysis in childhood acute lymphoblastic leukemia: experience at a single institution in Korea

We evaluated major cytogenetic abnormalities associated with childhood acute lymphoblastic leukemia (ALL) through both fluorescent in situ hybridization and conventional chromosomal analysis for 132 ALL patients diagnosed at St Mary’s Hospital in Korea. Chromosome abnormalities have been detected in 92% of patients. Eighteen (14%) patients showed numerical abnormalities only, 50 (38%) patients showed structural abnormalities only, and 53 (40%) patients showed both. The simultaneous trisomies 4, 10 and 17 were observed in 23 (17%) patients. Of the patients with abnormal karyotypes, recurrent structural abnormalities were determined in 103 (78%) cases. t(12;21)(q13;q22) was found in 29 (22%) out of 132 patients, 9p abnormalities in 13 (10%) patients, t(1;19)(q23;p13.3) in 11 (8%) patients, t(9;22)(q34;q11.2) in 11 (8%) patients, and 11q23 abnormalities in 7 (5%) patients. Interestingly, we identified five uncommon translocations such as t(5;12) (q33;p13), t(14;19)(q32;q13.1), t(12;16)(p13;q13), der(1)t(1;12)(p32;p13), and t(5;15)(p15;q11.2). Our study pool is representative of pediatric ALL patients in Korea as it consists of about 20% of patients diagnosed annually in Korea. We believe that the data provided will aid in comparative studies of the treatment outcomes, as well as the type and incidence of chromosomal abnormalities associated with childhood ALL in various Asian nations and Western countries.

Recent incidence of congenital heart disease in neonatal care unit of secondary medical center: a single center study

Purpose With feasibility in the diagnoses of congenital heart disease (CHD) in the antenatal period, we suspect changes have occurred in its incidence. No data have been reported about the current incidence of simple forms of CHD in Korea. We have attempted to assess the recent incidence and characteristics of CHD in the neonatal care unit of a secondary referral medical center. Methods Medical records of 497 neonatal care unit patients who underwent echocardiography in the past 5 years were reviewed. Pre-term infants with patent ductus arteriosus and other transient, minimal lesions were excluded from this study. Results Although the number of inpatients remained stable, the incidence of simple forms of CHD showed a gradual decrease over the 5-year study period; a markedly low incidence of complex forms was seen as well. CHD was observed in 3.7% full-term and 6.8% pre-term infants. CHD was observed in 152 infants weighing >2,500 g (3.5% of corresponding birth weight infants); 65 weighing 1,000 to 2,500 g (9.3%); and 6 weighing <1,000 g (8.0%). The incidence of CHD was higher in the pre-term group and the low birth weight group than in each corresponding subgroup (P<0.001); however, the incidence of complex CHD in full-term neonates was high. The number of patients with extracardiac structural anomalies has also shown a gradual decrease every year for the past 5 years. Conclusion Findings from our study suggest that the recent incidence and disease pattern of CHD might have changed for both complex and simple forms of CHD in Korea.

Usefulness of anterior uveitis as an additional tool for diagnosing incomplete Kawasaki disease

Purpose There are no specific tests for diagnosing Kawasaki disease (KD). Additional diagnostic criteria are needed to prevent the delayed diagnosis of incomplete Kawasaki disease (IKD). This study compared the frequency of coronary artery lesions (CALs) in IKD patients with and without anterior uveitis (AU) and elucidated whether the finding of AU supported the diagnosis of IKD. Methods This study enrolled patients diagnosed with IKD at The Catholic University of Korea, Uijeongbu St. Marys Hospital from January 2010 to December 2014. The patients were divided into 2 groups: group 1 included patients with IKD having AU; and group 2 included patients with IKD without AU. We analyzed the demographic and clinical data (age, gender, duration of fever, and the number of diagnostic criteria), laboratory results, and echocardiographic findings. Results Of 111 patients with IKD, 41 had uveitis (36.98%, group 1) and 70 did not (63.02%, group 2). Patients in group 1 had received a diagnosis and treatment earlier, and had fewer CALs (3 of 41, 1.7%) than those in group 2 (20 of 70, 28.5%) (P=0.008). All 3 patients with CALs in group 1 had coronary dilatation, while patients with CALs in group 2 had CALs ranging from coronary dilatation to giant aneurysm. Conclusion The diagnosis of IKD is challenging but can be supported by the presence of features such as AU. Group 1 had a lower risk of coronary artery disease than group 2. Therefore, the presence of AU is helpful in the early diagnosis and treatment of IKD and can be used as an additional diagnostic tool.

Prediction of nonresponsiveness to medium- dose intravenous immunoglobulin (1 g/kg) treatment: an effective and safe schedule of acute treatment for Kawasaki disease

Purpose Medium-dose (1 g/kg) intravenous immunoglobulin (IVIG) is effective in the majority of patients with Kawasaki disease (KD) but some patients who do not respond to medium-dose IVIG are at high risk for the development of coronary artery lesions (CALs). The purpose of this study was to identify the clinical predictors associated with unresponsiveness to medium-dose IVIG and the development of CALs. Methods A retrospective study was performed in 91 children with KD who were treated with medium-dose IVIG at our institution from January 2004 to December 2013. We classified the patients into responders (group 1; n=68) and nonresponders (group 2; n=23). We compared demographic, laboratory, and echocardiographic data between the 2 groups. Results Multivariate logistic regression analysis identified 6 variables as predictors for resistance to medium-dose IVIG. We generated a predictive scoring system assigning 1 point each for percentage of neutrophils ≥65%, C-reactive protein≥100 mg/L, aspartate aminotransferase≥100 IU/L, and alanine aminotransferase≥100 IU/L, as well as 2 points for less than 5 days of illness, and serum sodium level≤136 mmol/L. Using a cutoff point of ≥4 with this scoring system, we could predict nonresponsiveness to medium-dose IVIG with 74% sensitivity and 71% specificity. Conclusion If a patient has a low-risk score in this system, medium-dose IVIG can be recommended as the initial treatment. Through this process, we can minimize the adverse effects of high-dose IVIG and incidence of CALs.