Purpose: Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods: From January 2001 to December 2015, data of pediatric patients (0–18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results: Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range 0-225.5) and median follow-up duration was 88.5 months (range 0-211.6). Overall, 32 patients died, of whom 17, 11, 1, and 3 died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea.

Purpose: Acute promyelocytic leukemia (APL) is a rare disease in children and there are some different characteristics between children and adult. We aimed to evaluate incidence, clinical characteristics and treatment outcomes of pediatric APL in Korea. Materials and Methods: Seventy-nine pediatric APL patients diagnosed from January 2009 to December 2016 in 16 tertiary medical centers in Korea were reviewed retrospectively. Results: Of 801 acute myeloid leukemia children, 79 (9.9%) were diagnosed with APL. The median age at diagnosis was 10.6 years (range, 1.3 to 18.0). Male and female ratio was 1:0.93. Thirty patients (38.0%) had white blood cell (WBC) count greater than 10×109/L at diagnosis. All patients received induction therapy consisting of all-trans retinoic acid and chemotherapy. Five patients (6.6%) died during induction chemotherapy and 66 patients (86.8%) achieved complete remission (CR) after induction chemotherapy. The causes of death were three intracranial hemorrhage, one cerebral infarction, and one sepsis. Five patients (7.1%) suffered a relapse during or after maintenance chemotherapy. The estimated 4-year event-free survival and overall survival (OS) rates were 82.1%±4.4%, 89.7%±5.1%, respectively. The 4-year OS was significantly higher in patients with initial WBC < 10×109/L than in those with initial WBC ≥ 10×109/L (p=0.020). Conclusion This study showed that the CR rates and survival outcomes in Korean pediatric APL patients were relatively good. The initial WBC count was the most important prognostic factor and most causes of death were related to serious bleeding in the early stage of treatment.

Background: Hereditary hemolytic anemia (HHA) is a rare disease characterized by premature red blood cell (RBC) destruction due to intrinsic RBC defects. The RBC Disorder Working Party of the Korean Society of Hematology established and updated the standard operating procedure for making an accurate diagnosis of HHA since 2007. The aim of this study was to investigate a nationwide epidemiology of Korean HHA. Methods: We collected the data of a newly diagnosed pediatric HHA cohort (2007–2016) and compared this cohort's characteristics with those of a previously surveyed pediatric HHA cohort (1997–2006) in Korea. Each participant's information was retrospectively collected by a questionnaire survey. Results: A total of 369 children with HHA from 38 hospitals distributed in 16 of 17 districts of Korea were investigated. RBC membranopathies, hemoglobinopathies, RBC enzymopathies, and unknown etiologies accounted for 263 (71.3%), 59 (16.0%), 23 (6.2%), and 24 (6.5%) of the cases, respectively. Compared to the cohort from the previous decade, the proportions of hemoglobinopathies and RBC enzymopathies significantly increased (P < 0.001 and P = 0.008, respectively). Twenty-three of the 59 hemoglobinopathy patients had immigrant mothers, mostly from South-East Asia. Conclusion In Korea, thalassemia traits have increased over the past 10 years, reflecting both increased awareness of this disease and increased international marriages. The enhanced recognition of RBC enzymopathies is due to advances in diagnostic technique; however, 6.5% of HHA patients still do not have a clear diagnosis. It is necessary to improve accessibility of diagnosing HHA.

Background: Hodgkin's lymphoma (HL) constitutes 10%–20% of all malignant lymphomas and has a high cure rate (5-year survival, around 90%). Recently, interest has increased concerning preventing secondary complications (secondary cancer, endocrine disorders) in long-term survivors. We aimed to study the epidemiologic features and therapeutic outcomes of HL in children, adolescents, and young adults in Korea. Methods: We performed a multicenter, retrospective study of 224 patients aged < 25 years diagnosed with HL at 22 participating institutes in Korea from January 2007 to August 2016. Results: A higher percentage of males was diagnosed at a younger age. Nodular sclerosis histopathological HL subtype was most common, followed by mixed cellularity subtype.Eighty-one (36.2%), 101 (45.1%), and 42 (18.8%) patients were classified into low, intermediate, and high-risk groups, respectively. Doxorubicin, bleomycin, vinblastine, dacarbazine was the most common protocol (n = 102, 45.5%). Event-free survival rate was 86.0% ± 2.4%, while five-year overall survival (OS) rate was 96.1% ± 1.4%: 98.7% ± 1.3%, 97.7% ± 1.6%, and 86.5% ± 5.6% in the low, intermediate, and high-risk groups, respectively (P = 0.021). Five-year OS was worse in patients with B-symptoms, stage IV disease, highrisk, splenic involvement, extra-nodal lymphoma, and elevated lactate dehydrogenase level.In multivariate analysis, B-symptoms and extra-nodal involvement were prognostic factors for poor OS. Late complications of endocrine disorders and secondary malignancy were observed in 17 and 6 patients, respectively. Conclusion This is the first study on the epidemiology and treatment outcomes of HL in children, adolescents, and young adults in Korea. Future prospective studies are indicated to develop therapies that minimize treatment toxicity while maximizing cure rates in children, adolescents, and young adults with HL.

PURPOSE: Despite the increasing use of continuous renal replacement therapy (CRRT) in the neonatal intensive care unit (NICU), few studies have investigated its use in preterm infants. This study evaluated the prognosis of preterm infants after CRRT and identified risk factors of mortality after CRRT. MATERIALS AND METHODS: A retrospective review was performed in 33 preterm infants who underwent CRRT at the NICU of Samsung Medical Center between 2008 and 2017. Data of the demographic characteristics, predisposing morbidity, cardiopulmonary function, and CRRT were collected and compared between surviving and non-surviving preterm infants treated with CRRT. Univariable and multivariable analyses were performed to identify factors affecting mortality. RESULTS: Compared with the survivors, the non-survivors showed younger gestational age (29.3 vs. 33.6 weeks), lower birth weight (1359 vs. 2174 g), and lower Apgar scores at 1 minute (4.4 vs. 6.6) and 5 minutes (6.5 vs. 8.6). At the initiation of CRRT, the non-survivors showed a higher incidence of inotropic use (93% vs. 40%, p=0.017) and fluid overload (16.8% vs. 4.0%, p=0.031). Multivariable analysis revealed that fluid overload >10% at CRRT initiation was the primary determinant of mortality after CRRT in premature infants, with an adjusted odds ratio of 14.6 and a 95% confidence interval of 1.10–211.29. CONCLUSION: Our data suggest that the degree of immaturity, cardiopulmonary instability, and fluid overload affect the prognosis of preterm infants after CRRT. Preventing fluid overload and earlier initiation of CRRT may improve treatment outcomes.
Birth Weight ; Gestational Age ; Humans ; Incidence ; Infant, Newborn ; Infant, Premature ; Intensive Care, Neonatal ; Mortality ; Odds Ratio ; Prognosis ; Renal Replacement Therapy ; Retrospective Studies ; Risk Factors ; Survivors

BACKGROUND: von Willebrand disease (VWD) is one of the most common inherited bleeding disorders. However, the number of patients who register to the Korea Hemophilia Foundation (KHF) is much lower than the expected prevalence rate and only few hospitals perform tests for diagnosis autonomously. Thus, we surveyed practical realities of VWD in Yeungnam region. METHODS: Patients with VWD (N=267) who were diagnosed at eleven university hospitals from March 1995 to March 2018 were enrolled in this study. We evaluated the medical records from each hospital retrospectively. RESULTS: Two hundred and twenty-eight children and 39 adults met the diagnostic criteria for VWD. Seventy-eight (57.4%) patients had the blood type O. Fifty-eight patients were definite type 1 (21.7%), 151 were possible type 1 (56.6%), and the others were type 2. Abnormal laboratory findings were the most common factor for the diagnosis in children. VWF mutations were detected in 17 patients. Patients with a family history showed age of diagnosis of 9 y, which is higher than in those with no family history (6 yr), and also showed a higher rate of significant bleeding (32.1% vs. 14.2%). VWF:RCo and VWF:Ag tests were performed in-hospital at only 1 of 11 hospitals. Twelve of 267 patients were enrolled at the KHF (4.5%). CONCLUSION: A high rate of out-sourcing studies may result in inaccurate diagnosis. The registration rate to the KHF is still lower than the prevalence rate. A comprehensive nationwide registration system is necessary in order to identify the actual prevalence rate and promote the diagnosis of VWD in Korea.
Adult ; Child ; Diagnosis ; Hemophilia A ; Hemorrhage ; Hospitals, University ; Humans ; Korea ; Medical Records ; Prevalence ; Retrospective Studies ; von Willebrand Diseases

BACKGROUND: Venous thromboembolism (VTE) is rare in pediatric patients compared to adults, but it's incidence is gradually increasing. The purpose of this study was to analyze the incidence, risk factors, and prognosis of pediatric patients with VTE in Korea. METHODS: Between January 2000 and July 2017, 249,312 medical records of the patients older than 1 year who were hospitalized in the department of pediatrics of 10 university hospitals in Yeungnam region were retrospectively reviewed. RESULTS: The overall incidence of VTE was 4.9 per 10,000 admissions. Of the total 123 patients, 80 (65.0%) were male and the median age was 10.8 years (range, 1.0–23.5 years). Magnetic resonance imaging was performed most frequently to confirm the diagnosis of VTE (43.1%). Thrombosis occurred in the cerebral vessels (46.3%), lower extremities (23.8%), pulmonary (19.5%), abdomen (9.8%), and upper extremities (4.1%). One hundred and six patients had underlying causes such as cancer (27.6%), infection (26.8%), intravenous catheter insertion (17.9%), and surgery (14.6%). Protein C was evaluated in 39 patients (31.7%), protein S in 40 (32.5%), antithrombin (AT) III in 52 (42.3%), and homocysteine in 21 (17.1%). Among them, one patient with a family history of AT III deficiency had SERPINC gene mutation. Seventy-seven patients (62.6%) started anticoagulation treatment. Most (52.0%) were treated for more than 90 days. CONCLUSION: Healthcare providers must be aware of the potential for VTE development in childhood. In the near future, a nationwide survey should be investigated to determine the incidence rate and the trends in VTE among Korean children.
Abdomen ; Adult ; Catheters ; Child ; Diagnosis ; Epidemiology ; Health Personnel ; Homocysteine ; Hospitals, University ; Humans ; Incidence ; Korea* ; Lower Extremity ; Magnetic Resonance Imaging ; Male ; Medical Records ; Pediatrics ; Prognosis ; Protein C ; Protein S ; Retrospective Studies ; Risk Factors ; Thrombosis ; Upper Extremity ; Venous Thromboembolism*

BACKGROUND: From May to July 2015, the Republic of Korea experienced the largest outbreak of Middle East respiratory syndrome (MERS) outside the Arabian Peninsula. A total of 186 patients, including 36 deaths, had been diagnosed with MERS-coronavirus (MERS-CoV) infection as of September 30th, 2015. MATERIALS AND METHODS: We obtained information of patients who were confirmed to have MERS-CoV infection. MERS-CoV infection was diagnosed using real-time reverse-transcriptase polymerase chain reaction assay. RESULTS: The median age of the patients was 55 years (range, 16 to 86). A total of 55.4% of the patients had one or more coexisting medical conditions. The most common symptom was fever (95.2%). At admission, leukopenia (42.6%), thrombocytopenia (46.6%), and elevation of aspartate aminotransferase (42.7%) were observed. Pneumonia was detected in 68.3% of patients at admission and developed in 80.8% during the disease course. Antiviral agents were used for 74.7% of patients. Mechanical ventilation, extracorporeal membrane oxygenation, and convalescent serum were employed for 24.5%, 7.1%, and 3.8% of patients, respectively. Older age, presence of coexisting medical conditions including diabetes or chronic lung disease, presence of dyspnea, hypotension, and leukocytosis at admission, and the use of mechanical ventilation were revealed to be independent predictors of death. CONCLUSION: The clinical features of MERS-CoV infection in the Republic of Korea were similar to those of previous outbreaks in the Middle East. However, the overall mortality rate (20.4%) was lower than that in previous reports. Enhanced surveillance and active management of patients during the outbreak may have resulted in improved outcomes.
Antiviral Agents ; Aspartate Aminotransferases ; Coronavirus Infections* ; Disease Outbreaks ; Dyspnea ; Extracorporeal Membrane Oxygenation ; Fever ; Humans ; Hypotension ; Leukocytosis ; Leukopenia ; Lung Diseases ; Middle East Respiratory Syndrome Coronavirus ; Middle East* ; Mortality ; Pneumonia ; Polymerase Chain Reaction ; Republic of Korea* ; Respiration, Artificial ; Thrombocytopenia

PURPOSE: Initial orthostatic hypotension is typically associated with active standing and normal autonomic function. Some adolescents in the present study displayed initial orthostatic hypotension during passive tilting, and we hypothesized that this condition was due to abnormal autonomic function. METHODS: The present study compared autonomic functioning in two groups of adolescents: patients with a diagnosis of initial orthostatic hypotension according to the tilt table test and patients with typical symptoms of initial orthostatic hypotension but normal tilt table test results. RESULTS: Significantly higher total composite autonomic severity scores and considerably higher adrenergic index were noted in the tilt table tested group. CONCLUSION: Initial orthostatic hypotension is possibly associated with autonomic dysfunction, especially abnormal vasoconstrictive ability, in individuals diagnosed with a tilt table test. Clinicians should take note of autonomic function when performing diagnoses of initial orthostatic hypotension using the tilt table test.
Adolescent ; Humans ; Hypotension, Orthostatic ; Tilt-Table Test