Influence of creatinine levels on survival in patients with veno-occlusive disease treated with defibrotide

Background/Aims@#Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is one of the most fatal complications of hematopoietic cell transplantation (HCT), and defibrotide is the only curative drug. We conducted this study to confirm the survival rate of VOD/SOS patients diagnosed in Korea and assess the efficacy of defibrotide. @*Methods@#Patients diagnosed with VOD/SOS after allogenic HCT between 2003 and 2020 were enrolled. We investigated day +100 survival rates and associated risk factors in patients who satisfied the modified Seattle criteria within 50 days of HCT. @*Results@#A total of 110 patients satisfied the modified Seattle criteria, of which 65.5% satisfied the Baltimore criteria. Thirty-seven patients were treated with defibrotide. The day +100 survival rate of the 110 patients was 65.3%. The survival rates in patients who did not meet the Baltimore criteria and in those who did were 86.8% and 53.7%, respectively (p = 0.001). The day +100 survival rate of patients treated with defibrotide was 50.5%. Among the patients receiving defibrotide, those whose creatinine levels were more than 1.2 times the baseline had a significantly lower survival rate at 26.7% (p = 0.014). On multivariate regression analysis, the hazard ratio of satisfaction of the Baltimore criteria was 4.54 (95% confidence interval [CI], 1.69 to 12.21; p = 0.003). In patients treated with defibrotide, the hazard ratio was 8.70 (95% CI, 2.26 to 33.45; p = 0.002), when creatinine was more than 1.2 times the baseline on administration. @*Conclusions@#The day +100 survival rate was significantly lower when the Baltimore criteria were satisfied, and when there was an increase in creatinine at the time of defibrotide administration.

Clinical Characteristics and Treatment Outcomes of Childhood Acute Promyelocytic Leukemia in Korea: A Nationwide Multicenter Retrospective Study by Korean Pediatric Oncology Study Group / Journal of the Korean Cancer Association, 대한암학회지

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.

Comparative Analysis of Course Satisfaction and Student Assessment Results in Redesigned Problem-Based Learning / 의학교육논단

The purpose of this study was to redesign a problem-based learning (PBL) curriculum and compare the differences between the previous and redesigned PBL based on the results of course satisfaction and student assessments. The PBL was redesigned using curriculum design guidelines (including revisions of curriculum objectives, learning components, learning environments, and assessment methods) that were developed based on previous studies and evaluation results. A comparative study was employed using course satisfaction surveys from the previous and redesigned curricula, and a total of 45 students participated. We also compared student assessment results from concept mapping, learning issue reports, modified essay questions, and reflection journals. We identified four key findings. First, we explored the possibility that the redesigned PBL could be implemented by student facilitators without professors as tutors. Second, the redesigned PBL fostered group dynamics that facilitated developing communication skills and collaborative learning through small-group discussions. Third, the new learning elements added in the redesigned PBL made a meaningful contribution to enhancing students’ clinical reasoning based on hypothetico-deductive reasoning. Fourth, concept maps in redesigned PBL contained more complex and various nodes and connections, and the levels of the nodes were more appropriate. The implications of this study can provide meaningful preliminary information for redesigning PBL curricula for medical students to develop their essential competencies through PBL.

RUNX1 Germline Mutation in a Patient with Chronic Thrombocytopenia / 임상소아혈액종양

One of the pathophysiologic mechanism of inherited thrombocytopenia is a defect in transcription factors that regulate the expression of multiple genes required for megakaryopoiesis. Runt-related transcription factor 1 (RUNX1) binds to its heterodimeric partner, core binding factor beta (CBFβ), and forms a core binding factor that regulates the expression of various target genes. The association between RUNX1 germline mutations and familial platelet disorder with associated myeloid malignancy was first reported in 1999. Although this disease has various phenotypes and penetration, the most common symptom is a bleeding tendency due to thrombocytopenia and platelet dysfunction. Myelodysplastic syndromes or acute myeloid leukemia may also develop in 35-40% of cases. We identified a heterozygous mutation in the RUNX1 gene using diagnostic exome sequencing in an adolescent with chronic thrombocytopenia.The patient will be followed continuously for hematologic malignancies that may develop in the future. This case illustrates the importance of diagnosing inherited thrombocytopenia to provide adequate follow-up for hematologic malignancies and reduce unnecessary treatment.

Epidemiological Study of Hereditary Hemolytic Anemia in the Korean Pediatric Population during 1997–2016: a Nationwide Retrospective Cohort Study

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.

A Multicenter Study on von Willebrand Disease Realities in Yeungnam Region / 임상소아혈액종양

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.

First case report of latent tuberculosis reactivation complicating treatment with nilotinib in chronic myeloid leukemia

No abstract available.

Current use of safety restraint systems and front seats in Korean children based on the 2008–2015 Korea National Health and Nutrition Examination Survey / 소아과

PURPOSE: The use of proper safety restraint systems by children is vital for the reduction of traffic accident-related injury and death. This study evaluated the rates of use of safety restraint systems and front seats by Korean children. METHODS: Based on data from the National Health and Nutrition Examination Survey from 2008 to 2015, I investigated the frequencies of safety restraint systems and front seat use by children under six and 12 years of age, respectively. RESULTS: The percentage of respondents who said they always use safety restraint systems increased from 17.7% in 2008 to 45.0% in 2015. The rate of children who did not use the front seats at all was 47.3 % in 2008 compared to 33.4% in 2015. Multivariate logistic regression analysis showed a decrease in safety-restraint-system use as age increased (odds ratio, 0.63; 95% confidence interval [CI], 0.51–0.77). The use rate of front-passenger seat belts by the mother is significantly correlated with the safety-restraint- system use rate by children (odds ratio, 2.14; 95% CI, 1.12–4.06). CONCLUSION: Although the rate of safety-restraint-system use for children is increasing annually, it remains low. Additionally, the use rate of front passenger seats for children is high. To reduce the rates of injury and death of children from traffic accidents, it is necessary to educate on the appropriate use of safety restraint systems according to age and body size and to develop stronger regulations.

Comparison of Hemoglobin Correction Effects According to Storage Period and Other Factors in the Transfusion of Packed Red Blood Cells in Neonatal Intensive Care Unit Patients

PURPOSE: Preterm infants frequently require red blood cell (RBC) transfusions in neonatal intensive care units (NICU). Storage RBCs undergo many changes during storage periods. We aimed to compare the hemoglobin (Hb) correction effect according to the period of RBC storage and investigate the factors influencing Hb correction. METHODS: This retrospective study reviewed the medical records of 289 patients who received RBC transfusion more than once in the NICU of Kosin University Gospel Hospital between February 2006 and March 2016. The subjects were classified into two storage groups: short-term (≤7 days, n=88) and long-term (>7 days, n=201), according to the period of RBC storage. We checked Hb levels by complete blood cell count tests conducted within 2 days before and 5 to 9 days after the first transfusion. We compared the Hb difference between the two groups and analyzed the factors influencing Hb correction. RESULTS: Excluding the use of an invasive ventilator, there was no significant difference between the two groups in terms of clinical characteristics. There was no significant difference in the Hb correction effect between the two groups (P=0.537). Birth weight greater than 1,500 g, higher weight at transfusion, and larger volume of transfusion were significant prognostic factors affecting greater changes in Hb. In addition, surgery experience, higher Hb level at transfusion, and additional blood tests were found to be significantly associated with less changes in Hb. CONCLUSION: The RBC storage period did not affect the Hb correction effect. The Hb correction effect may be diminished in infants with lower birth weight and lower weight at transfusion under unstable clinical conditions.

A Case of Transient Myeloproliferative Disorder Associated with Clonal Trisomy 21 in a Chromosomally Normal Newborn / 임상소아혈액종양

Transient myeloproliferative disorder (TMD) is similar to congenital leukemia, with leukocytosis, increased peripheral blast cells, and hepatomegaly in the neonatal period. Although TMD occurs only in patients with Down syndrome and trisomy 21 mosaicism, there have been reports of congenital leukemia with trisomy 21 limited to hematopoietic cells showing spontaneous resolution. We identified trisomy 21 in the leukemic cells in a patient with congenital leukemia. As there was no other gene abnormality, we stopped chemotherapy, and the disease resolved spontaneously. We reviewed the cases of clonal trisomy 21 TMD and found that their clinical features were similar to those of TDM associated with Down syndrome. In conclusion, in a phenotypically normal patient with suspected congenital leukemia, it is necessary to confirm the presence of 21 trisomy. If the neonate has only trisomy 21 without other gene abnormalities, intensive chemotherapy may not be required.

A Case of Sickle Cell Anemia with a Lack of High Frequency Red Blood Cell Antigen / 대한수혈학회지

Patients with sickle cell anemia are chronically transfused. Therefore, it is important to prevent the alloimmunization of RBC antigens. The authors identified a high frequency antigen-negative blood group in patients with sickle cell anemia. As the number of foreigners residing in Korea is increasing, it is necessary to know what to consider when transfusing blood to sickle cell anemia patients. Patients with sickle cell anemia should be informed of the exact blood group type using extended RBC typing to confirm the ABO, Rh, Kell, and Duffy blood types at diagnosis or before the first blood transfusion. Extended matched blood transfusion can reduce the risk of alloimmunization of RBC antigens.

Antibiotic resistance of Staphylococcus aureus colonized in children with staphylococcal scalded skin syndrome / 고신대학교의과대학학술지

OBJECTIVES: Systemic antibiotic therapy with semisynthetic penicillinase-resistant penicillin or vancomycin and clindamycin are recommended for the treatment of staphylococcal scalded skin syndrome (SSSS). This study assessed the rate of antibiotic resistance of Staphylococcus aureus isolated from the anterior nares or skin of children diagnosed with SSSS. METHODS: A retrospective review of the medical records of 25 patients with SSSS between July 2010 and October 2014 was conducted. The clinical characteristics of patients were collected and the antibiotic susceptibility of S. aureus were analyzed using automated systems. RESULTS: The median age of the patients was 22 months (range: 2–95). Ninety-two percent of patients were less than 5 years of age. Nasal swab samples of all patients and skin swab samples of 17 patients were cultured to isolate S. aureus. Twenty-one (84%) of 25 patients were colonized with methicillin-resistant S. aureus (MRSA). The results of swab samples of the other four patients were no growth or isolation of bacteria other than S. aureus. Among 20 strains isolated from the anterior nares, 1 strain (5%) was methicillin-susceptible S. aureus. All 15 strains isolated from the skin were MRSA. All 21 strains isolated from anterior nares or skin were found to be resistant to clindamycin upon evaluation using automated systems. CONCLUSIONS: The rates of methicillin and clindamycin resistance in S. aureus colonized in children with SSSS were very high. Further studies evaluating proper antibiotic regimens and the effectiveness of systemic antibiotic therapy are needed.

Childhood Venous Thromboembolism in Yeungnam Region in Korea: Multicenter Study / 임상소아혈액종양

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.

PHACE Syndrome with Large Facial Segmental Hemangioma and Cerebellar Hypoplasia / 임상소아혈액종양

Infantile hemangiomas are the most common benign tumors in infants. Facial segmental hemangiomas are often accompanied by other anomalies, and pre-treatment evaluation is needed. PHACE syndrome is associated with Posterior fossa anomalies, Hemangiomas, Arterial anomalies, Cardiac anomalies, and Eye anomalies (PHACE). PHACE syndrome is diagnosed in about 30% of patients with facial segmental hemangiomas. In PHACE syndrome, facial hemangioma usually requires initial treatment; propranolol use is increasing as a first-line treatment despite the risk of stroke. We report a case of PHACE syndrome in a patient with large facial hemangiomas, left cerebellar hypoplasia, and an absent A1 segment of the anterior cerebral artery. After 1 year of treatment with oral propranolol, facial hemangiomas improved and normal development was observed until 24 months of age. Evaluation of PHACE syndrome is important in patients with large facial segmental hemangiomas, and propranolol can be considered a first-line therapy for hemangioma.

PHACE Syndrome with Large Facial Segmental Hemangioma and Cerebellar Hypoplasia / 임상소아혈액종양

Infantile hemangiomas are the most common benign tumors in infants. Facial segmental hemangiomas are often accompanied by other anomalies, and pre-treatment evaluation is needed. PHACE syndrome is associated with Posterior fossa anomalies, Hemangiomas, Arterial anomalies, Cardiac anomalies, and Eye anomalies (PHACE). PHACE syndrome is diagnosed in about 30% of patients with facial segmental hemangiomas. In PHACE syndrome, facial hemangioma usually requires initial treatment; propranolol use is increasing as a first-line treatment despite the risk of stroke. We report a case of PHACE syndrome in a patient with large facial hemangiomas, left cerebellar hypoplasia, and an absent A1 segment of the anterior cerebral artery. After 1 year of treatment with oral propranolol, facial hemangiomas improved and normal development was observed until 24 months of age. Evaluation of PHACE syndrome is important in patients with large facial segmental hemangiomas, and propranolol can be considered a first-line therapy for hemangioma.

Massive Fetomaternal Hemorrhage Diagnosed with High-performance Liquid Chromatography / 임상소아혈액종양

Massive fetomaternal hemorrhage (FMH) is a major cause of unexplained fetal death and neonatal anemia. FMH can be diagnosed using the Kleihauer-Betke test or flow cytometry by identifying the presence of fetal red cells in the maternal blood. However, timely diagnosis is a challenge because many hospitals lack the equipment needed to perform such tests. The authors experienced a case of FMH diagnosed via high-performance liquid chromatography (HPLC) which is generally used in measuring glycated hemoglobin (HbA1c) in a patient with unexplained neonatal anemia. A girl aged 2 days was transferred to our hospital for showing pallor and a hemoglobin level of 5.0 g/dL. HPLC revealed 3% fetal hemoglobin (HbF) in the maternal blood. HPLC is a quick test for quantifying HbF that is readily available in many hospitals and could serve as a promising alternative for diagnosing FMH.

Influenza A Outbreak in a Neonatal Intensive Care Unit During the 2011-2012 Influenza Season in Korea

PURPOSE: An outbreak of influenza virus is uncommon in neonatal intensive care unit (NICU). The clinical presentation of influenza virus infection in neonates is diverse. This study was aimed to report an outbreak of influenza A in a NICU and to investigate the clinical characteristics of influenza virus infection in neonates especially preterm infants during the 2011-2012 influenza season in Korea. METHODS: We reviewed the medical records of 29 patients who were evaluated by respiratory virus multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) at NICU of Kosin University Gospel Hospital during the 2011-2012 seasonal influenza outbreak in Korea. RESULTS: Eleven patients (37.9%) were influenza A virus RT-PCR positive during the survey periods. They were all preterm infants and three of them had no symptoms. Eight patients had symptoms and it was fever (18%, 2/11), respiratory difficulty (72.7%, 8/11) without symptoms of upper respiratory infection, and gastrointestinal symptoms (27.3%, 3/11). The median duration of symptom was 5 days. There were differences of duration of admission at the test of respiratory RT-PCR, Clinical Risk Index for Babies (CRIB) score, use of mechanical ventilation, and use of dexamethasone before infection between influenza A virus RT-PCR positive and negative group. All 11 patients with influenza A were discharged without any complications. CONCLUSIONS: The symptoms of influenza A virus infection in the preterm infants is nonspecific. Influenza A virus should be considered as a possible cause of infection in NICU during the influenza season in the community.

Massive Fetomaternal Hemorrhage Diagnosed with High-performance Liquid Chromatography / 임상소아혈액종양

Massive fetomaternal hemorrhage (FMH) is a major cause of unexplained fetal death and neonatal anemia. FMH can be diagnosed using the Kleihauer-Betke test or flow cytometry by identifying the presence of fetal red cells in the maternal blood. However, timely diagnosis is a challenge because many hospitals lack the equipment needed to perform such tests. The authors experienced a case of FMH diagnosed via high-performance liquid chromatography (HPLC) which is generally used in measuring glycated hemoglobin (HbA1c) in a patient with unexplained neonatal anemia. A girl aged 2 days was transferred to our hospital for showing pallor and a hemoglobin level of 5.0 g/dL. HPLC revealed 3% fetal hemoglobin (HbF) in the maternal blood. HPLC is a quick test for quantifying HbF that is readily available in many hospitals and could serve as a promising alternative for diagnosing FMH.

Treatment Outcomes and Prognostic Factors in Children with Non-Hodgkin Lymphoma at a Single Institution / 임상소아혈액종양

BACKGROUND: Treatment outcomes of children with non-Hodgkin lymphoma (NHL) have dramatically improved in recent years. However, there are few studies on the outcomes of pediatric NHL in Korea.METHODS: We retrospectively analyzed the outcomes of 34 children diagnosed with NHL and treated at Kosin University Gospel Hospital from Jan. 1987 to Dec. 2009, according to age, lactate dehydrogenase (LDH) level, histology, stage and involved site.RESULTS: The mean age of the subjects was 9.0 years. The abdomen and head/neck regions were the most common primary sites. On histologic classification, Burkitt lymphoma was the most common, followed by lymphoblastic lymphoma, diffuse large B-cell lymphoma, anaplastic large cell lymphoma, and unclassifiable, with respective incidences of 35.3%, 23.5%, 17.6%, 17.6%, and 5.9%. Various combination chemotherapies according to the diagnosis with mean treatment duration of 14.9 months showed 5 year event free survival (EFS) and 5 year overall survival (OS) rate of 67.7+/-8.0% and 79.3+/-7.0%, respectively. Nine out of the 34 patients relapsed, and the 5 year OS rates for those who relapsed vs. 25 patients without relapse were 44.4+/-16.6%, vs. 92.0+/-5.4%, respectively (P<0.01). Although 5 year EFS rate varied according to stage, 5 year OS rate were not different according to age, sex, LDH, stage, histology, or treatment period.CONCLUSION: The outcome of children with NHL treated in our setting was comparable to those of other large centers in Korea. No factor other than stage, including LDH, histologic subtype showed significant prognostic value.

Childhood acute lymphoblastic leukemia with hyperleukocytosis at presentation

BACKGROUND: Hyperleukocytosis caused by acute lymphoblastic leukemia (ALL) is associated with early morbidity and mortality due to hyperviscosity arising from the excessive number of leukocytes.This study was designed to assess the incidence of hyperleukocytosis, survival outcomes, and adverse features among pediatric ALL patients with hyperleukocytosis. METHODS: Between January 2001 and December 2010, 104 children with previously untreated ALL were enrolled at the Pusan National University Hospital. All of them were initially stratified based on the National Cancer Institute (NCI) risk; 48 (46.2%) were diagnosed with high-risk ALL. The medical charts of these patients were retrospectively reviewed. RESULTS: Twenty (19.2%) of the 104 children with ALL had initial leukocyte counts of >100x10(9)/L, and 11 patients had a leukocyte count of >200x10(9)/L. Male gender, T-cell phenotype, and massive splenomegaly were positively associated with hyperleukocytosis. Common early complications during induction therapy included renal dysfunction, and central nervous system hemorrhage. The complete remission (CR) rate for the pediatric ALL patients with hyperleukocytosis (94.1%) was similar to the overall CR rate (95.6%). The estimated 3-year event free survival (EFS) and overall survival of ALL children with hyperleukocytosis were 75.0% and 81.2%, respectively. However, patients with initial leukocyte counts >200x10(9)/L had a lower EFS than those with initial leukocyte counts 100-200x109/L (63.6% vs. 100%; P=0.046). CONCLUSION: The outcome of pediatric ALL cases with an initial leukocyte count >200x10(9)/L was very poor, probably due to early toxicity-related death during induction therapy.