Local control and toxicity outcomes following consolidative radiation therapy in patients with high-risk neuroblastoma: a 20-year experience at a single center.

BACKGROUND: Intensive multimodal treatment can improve survival in patients with high-risk neuroblastoma, and consolidative radiation therapy has contributed to local control. We examined the clinical outcomes of patients who underwent consolidative radiation therapy at our institution. METHODS: We retrospectively reviewed the records of patients with high-risk neuroblastoma who underwent consolidative radiation therapy from March 2001 to March 2021 at Asan Medical Center. Patients underwent multimodal treatment including high-dose chemotherapy, surgery, stem cell transplantation, and maintenance therapy. Radiation (median, 21.0 Gy; range, 14-36) was administered to the primary site and surrounding lymph nodes. RESULTS: This study included 37 patients, and the median age at diagnosis was 2.8 years (range, 1.3-10.0). Four patients exhibited local failure, and 5-year free-from locoregional failure rate was 88.7%, with a median followup period of 5.7 years. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 59.1% and 83.6%, respectively. Univariate analysis revealed that patients with neuron-specific enolase levels > 100 ng/mL had significantly worse DFS and OS (P = 0.036, 0.048), and patients with no residual disease before radiation therapy showed superior OS (P = 0.029). Furthermore, patients with 11q deletion or 17q gain exhibited poor DFS and OS, respectively (P = 0.021, 0.011). Six patients experienced grade 1 acute toxicity. Late toxicity was confirmed in children with long-term survival, predominantly hypothyroidism and hypogonadism, typically < grade 3, possibly attributed to combination treatment. Four patients experienced late toxicity ≥ grade 3 with chronic kidney disease, growth hormone abnormality, ileus, premature epiphyseal closure, and secondary tumor, and recovered by hospitalization or surgical treatment. CONCLUSIONS: In patients with high-risk neuroblastoma, consolidative radiotherapy to the primary tumor site resulted in excellent local control and a tolerable safety profile.

High-dose chemotherapy followed by autologous stem cell transplantation in pediatric patients with relapsed osteosarcoma.

BACKGROUND: Patients with relapsed osteosarcoma have poor treatment outcomes. High-dose chemotherapy with autologous stem cell transplantation (HDCT/ASCT) has been used in several high-risk malignant solid tumors; however, few studies have evaluated their role in treating osteosarcoma. We evaluated the effectiveness of HDCT/ASCT in relapsed pediatric osteosarcoma cases. PROCEDURE: We retrospectively reviewed the medical records of 40 patients diagnosed with and treated for relapsed osteosarcoma at Asan Medical Center and Samsung Medical Center from January 1996 to July 2019. RESULTS: The median age of this cohort was 13.4 years (range: 6.1-18.2). The cohort's 5-year overall survival (OS) was 51.0% ± 0.1% during a median follow-up period of 67.5 months. Twenty-five patients (62.5%) achieved complete remission (CR) with salvage treatment, and the 5-year OS was 82.4% ± 0.1%, whereas none of the remaining 15 patients who did not achieve CR survived (p < .0001). Of the 25 CR cases, 15 underwent subsequent HDCT/ASCT. We compared the effect of HDCT/ASCT among patients who achieved CR. There were no significant differences in the 5-year OS outcomes between patients who did and did not receive HDCT/ASCT (83.9% ± 0.1%, 13/15 vs. 80.0% ± 0.1%, 8/10, respectively; p = .923). CONCLUSION: To our knowledge, we report the first comparative cohort study that proved HDCT/ASCT does not significantly improve survival outcomes in relapsed osteosarcoma. Achievement of CR remains the most crucial factor for good survival outcomes.

Comorbidity Differences by Trajectory Groups as a Reference for Identifying Patients at Risk for Late Mortality in Childhood Cancer Survivors: Longitudinal National Cohort Study.

BACKGROUND: Childhood cancer has a high long-term morbidity and mortality rate. Five years after the initial cancer diagnosis, approximately two-thirds of childhood cancer survivors experience at least one late complication, with one-quarter experiencing severe, life-threatening complications. Chronic health conditions can impact survivors' life planning and daily activities, reducing their health-related quality of life. Comprehensive and longitudinal data are required for investigations of national claims data. OBJECTIVE: This study aimed to address clinical and health policy interventions and improved survival rates. A comprehensive categorization of the long-term morbidities associated with childhood cancer survivorship is required. We analyzed the trajectory groups associated with long-term mortality among childhood cancer survivors. METHODS: We collected data from a nationwide claims database of the entire Korean population. Between 2003 and 2007, patients diagnosed with and treated for cancer before the age of 20 years were included. With 8119 patients who survived >10 years, 3 trajectory groups were classified according to yearly changes in the number of diagnoses (the lowest in group 1 and the highest in group 3). RESULTS: The patterns of most comorbidities and survival rates differed significantly between the trajectory groups. Group 3 had a higher rate of mental and behavioral disorders, neoplasms, and blood organ diseases than the other two groups. Furthermore, there was a difference in the number of diagnoses by trajectory groups over the entire decade, and the disparity increased as the survival period increased. If a patient received more than four diagnoses, especially after the fourth year, the patient was likely to be assigned to group 3, which had the worst prognosis. Group 1 had the highest overall survival rate, and group 3 had the lowest (P<.001). Group 3 had the highest hazard ratio of 4.37 (95% CI 2.57-7.42; P<.001) in a multivariate analysis of late mortality. CONCLUSIONS: Our findings show that the pattern of comorbidities differed significantly among trajectory groups for late death, which could help physicians identify childhood cancer survivors at risk for late mortality. Patients with neoplasms, blood organ diseases, or mental and behavioral disorders should be identified as having an increased risk of late mortality. Furthermore, vigilance and prompt action are essential to mitigate the potential consequences of a child cancer survivor receiving four or more diagnoses within a year.

Epidemiologic and Clinical Outcomes of Pediatric Renal Tumors in Korea: A Retrospective Analysis of The Korean Pediatric Hematology and Oncology Group (KPHOG) Data.

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.

Favorable outcomes with durable chimerism after hematopoietic cell transplantation using busulfan and fludarabine-based reduced-intensity conditioning for pediatric patients with hemophagocytic lymphohistiocytosis.

Background: The incorporation of a reduced-intensity conditioning (RIC) regimen in hematopoietic cell transplantation (HCT) for patients with hemophagocytic lymphohistiocytosis (HLH) has decreased early mortality but is associated with a high rate of mixed chimerism and graft failure. Here, we present a successful single-center experience using busulfan and a fludarabine-based RIC regimen for the treatment of HLH. Methods: The medical records of pediatric patients with HLH who underwent HCT using a busulfan/ fludarabine-based RIC regimen between January 2008 and December 2017 were reviewed retrospectively. Results: Nine patients received HCT with a busulfan/fludarabine-based RIC regimen. Three patients had primary HLH, and the other six patients had secondary HLH with multiple reactivations. All three patients with primary HLH had UNC13D mutations. All patients achieved neutrophil and platelet engraftment at a median of 11 days (range, 10‒21) and 19 days (range, 13‒32), and all eight evaluable patients had sustained complete donor chimerism at the last follow-up. Two patients (22%) experienced grade 2 acute graft-versus- host disease (GVHD). Two patients (22%) developed chronic GVHD, and one died from chronic GVHD. One patient (11%) experienced reactivation 4 months after HCT from a syngeneic donor and died of the disease. The 8-year overall survival and event-free survival rates were 78%. No early treatment-related mortality within 100 days after HCT was observed. Conclusion: Our experience suggests that a busulfan/fludarabine-based RIC regimen is a viable option for pediatric patients with HLH who require HCT.

Recent improvement in survival outcomes and reappraisal of prognostic factors in hepatoblastoma.

BACKGROUND: Prognostic factors in hepatoblastoma need to be reevaluated considering the advances in treatment modalities. The study aimed to evaluate current outcomes of hepatoblastoma and reappraise the association of prognostic factors, including pre-treatment extent of tumor (PRETEXT) stage with annotation factors and Children's Hepatic tumors International Collaboration-Hepatoblastoma Stratification (CHIC-HS) system, with survival outcomes. METHODS: We evaluated 103 consecutive patients with hepatoblastoma retrospectively according to the treatment period based on the introduction of a liver transplantation program. RESULTS: The 5-year overall survival (OS), event-free survival (EFS), and transplant-free survival rates were 80.2%, 74.2%, and 61.8%, respectively. EFS and OS were improved significantly from 58.6% to 81.6% (P = 0.024) and from 58.6% to 90.8% (P < 0.001), respectively, in the late period (N = 74) compared with the early period (N = 29). The PRETEXT stage was significant or marginally significant for EFS and OS in the early period but not in the late period. The P, F, R, and C factors were significant for OS and EFS in the early period. However, in the late period, only the P factor was significant for OS, and the F and M factors were significant for EFS. The CHIC-HS system was significant or marginally significant for EFS in both the early and late periods; however, it was significant for OS only in the early period. CONCLUSION: Survival rates were significantly improved in children with hepatoblastoma, especially in those with advanced PRETEXT stages with positive annotation factors and in a high-risk CHIC-HS group. Prognostic factors had different clinical implications with evolved treatment modalities.

Erratum: Correction of Affiliations in the Article "Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study".

This corrects the article on p. e393 in vol. 35, PMID: 33258329.

Genetic Alterations Detected by Targeted Next-generation Sequencing and Their Clinical Implications in Neuroblastoma.

BACKGROUND/AIM: This study was conducted to evaluate the clinical usefulness of panel next-generation sequencing (NGS) and to investigate the spectrum of genetic alterations and their clinical implications in neuroblastoma. PATIENTS AND METHODS: Formalin-fixed, paraffin-embedded archival samples from 41 cases of neuroblastoma were used for targeted sequencing. RESULTS: A total of 145 somatic mutations were identified, including 51 synonymous, 86 missense, 3 nonsense, 2 frameshift deletion, 2 splice-site, and 1 in-frame deletion mutations. The most frequently mutated gene was ALK (9 missense mutations). The common copy number variations (CNVs) were amplification at 2p24.2 and deletion at 11q22.3 and 1p36.21. ALK mutations were more frequent in patients with stage 4 or 4S (0% vs. 33.3%, p=0.017). Among 27 patients with high-risk disease, the 5-year overall survival was inferior in patients with ALK mutations to those without (25.0% vs. 67.0%, p=0.009). CONCLUSION: Genetic analysis using targeted NGS was feasible and helpful in detecting point mutations and CNVs in neuroblastoma. Targeted NGS could predict prognosis and be used to find molecular target-based therapies for neuroblastoma.

Clinical Characteristics and Treatment Outcomes in Children, Adolescents, and Young-adults with Hodgkin's Lymphoma: a KPHOG Lymphoma Working-party, Multicenter, Retrospective Study.

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, high-risk, 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.

Differences in perspectives of pediatricians on advance care planning: a cross-sectional survey.

BACKGROUND: The increase in the number of pediatric patients with complex health conditions necessitates the application of advance care planning for children. Earlier, withdrawal of life-sustaining treatment was taboo in the medical society in South Korea due to the history of such practice being punishable by law, and physicians tended to pursue aggressive treatment. With changes in public opinion on end-of-life care, the Korean government enacted a new law that protect human dignity by respecting patients' self-determination and facilitating advance care planning. However, little is known about current state of advance care planning for pediatric patients. The study aimed to assess perceptions regarding advance care planning among South Korean pediatricians and clarify any differences in perception among pediatric subspecialties. METHODS: This study was an observational cross-sectional survey that used a web-based self-report questionnaire. Participants comprised of pediatricians currently caring for children with life-limiting conditions in 2018. RESULTS: Of the 96 respondents, 89 were included in the analysis. In a hypothetical patient scenario, more hemato-oncologists and intensivists than neonatologists and neurologists preferred to provide comfort care than aggressive treatment. While 72.2% of hemato-oncologists reported that they usually or always discuss advance care plans with parents during treatment, more than half of other pediatricians reported that they seldom do so. Furthermore, 65% of respondents said that they never discuss advance care planning with adolescent patients. Moreover, there were no notable differences among subspecialties. The most prevalent answers to factors impeding advance care planning were lack of systemic support after performing advance care planning (82.0%) and uncertain legal responsibilities (70.8%). CONCLUSIONS: The pediatricians differed in their experiences and attitudes toward advance care planning based on their subspecialty. Consequently, institutional support and education should be provided to physicians so that they can include children and families in discussions on prognosis.

Improved outcomes of allogeneic hematopoietic stem cell transplantation including haploidentical transplantation for childhood myelodysplastic syndrome.

This retrospective study aimed to investigate the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) for childhood myelodysplastic syndrome (MDS). Thirty-six patients (low-grade MDS, 24; advanced MDS, 12) received HSCT at the Asan Medical Center over two decades (early period, 1997-2007; recent period, 2008-2017). The transplantation outcomes were analyzed according to disease status, conditioning regimen, various donor types, and period of HSCT. During a median follow-up of 5.6 (range, 1.4-21.1) years, the probability of overall survival (OS) and failure-free survival was 77% and 69%, respectively. The cumulative incidence of transplantation-related mortality (TRM) was 12%. Significantly reduced TRM and improved OS were observed in patients who received HSCT during the recent period vs. the early period (TRM, 4% vs. 30%, P = 0.021; OS, 87% vs. 50%, P = 0.006). Comparable outcomes were observed for HSCT from haploidentical family donors vs. HLA-identical donors (TRM, 10% vs. 14%, P= 0.837; OS, 86% vs. 79%, P = 0.625). This study identified the improved outcomes of allogeneic HSCT for childhood MDS over time, in addition, the feasible outcomes of haploidentical HSCT suggested its use as an attractive alternative in the future procedures.

Development and Application of Advance Care Planning Workbooks to Facilitate Communication with Children and Adolescent Patients: A Pilot Test.

Purpose: This study presents the process of designing workbooks for advance care planning appropriate for the Korean cultural setting and describes actual case studies. Methods: This study focused on single inductive case studies of the utilization of an advance care planning workbook and recruited individual participants. Results: The workbook for adolescents contained six sessions and the workbook for children contained seven sessions. The workbook sessions led to four major discoveries 1) considering the Korean cultural context, discussions on life and death must be held indirectly; 2) the role of the counselor as a supporter is crucial for the workbook to be effective; 3) the workbook must be accessible regardless of the seriousness of the illness; and 4) patients must be able to make their own choice between the workbook versions for children and adolescents. Six facilitating factors improved engagement 1) the role of the counselor as a supporter; 2) building trust with the patient; 3) affirming freedom of expression on topics the patient wished to avoid talking about; 4) having discussions on what private information to keep secret and to whom the information can be disclosed; 5) discovering and regularly discussing relevant topics; and 6) regular communication and information-sharing with the patient's medical service providers. Conclusion: It is necessary to build on actual case studies regarding workbooks for children and adolescents in order to expand the usage of these workbooks to all relevant medical institutions in Korea.

Expression of Immune Checkpoint Receptors on T-Cells and Their Ligands on Leukemia Blasts in Childhood Acute Leukemia.

BACKGROUND: Possible correlations between the expression of immune checkpoint molecules and prognosis in childhood acute leukemia were investigated. MATERIALS AND METHODS: The expression of programmed-death 1 (PD1), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and B- and T-lymphocyte attenuator (BTLA) was determined by flow cytometry on peripheral αß+ and γδ+ T-cells from patients with newly diagnosed acute lymphoblastic leukemia (ALL) (n=9) or acute myeloid leukemia (AML) (n=12), and from healthy volunteers (n=7). The expression of programmed-death ligand 1 (PD-L1), B7-1, B7-2, human leukocyte antigen-ABC (HLA-ABC), and herpesvirus-entry mediator (HVEM) ligands was determined on leukemia blasts. RESULTS: PD1 expression on αß+ and γδ+ T-cells was significantly higher in patients with ALL than in those with AML (p=0.0019 and 0.0239, respectively). CTLA-4 expression was moderately higher on αß+ and γδ+ T-cells in ALL (p=0.077 and 0.077, respectively), whereas HLA-ABC expression was significantly higher in AML blast cells (p=0.0182). The expression of CTLA-4 on γδ+ T-cells and the B7-2 ligand on blasts was higher in patients with high-risk ALL (p=0.02 and 0.02, respectively). In AML, PD1 expression on αß+ T-cells was higher in the intermediate-risk group (p=0.05), whereas HVEM expression was significantly higher in the low-risk group (p=0.02). Expression of CTLA-4 on γδ+ T-cells and PD-L1 on blasts were both associated with poor relapse-free survival outcomes in ALL (p=0.049). CONCLUSION: The higher expression of immune checkpoint molecules, in particular, CTLA-4 and PD-L1 are associated with a poorer prognosis in ALL, suggesting that selective use of the immune checkpoint blockade might improve the clinical outcomes in patients with ALL.

Comparable Outcome with a Faster Engraftment of Optimized Haploidentical Hematopoietic Stem Cell Transplantation Compared with Transplantations from Other Donor Types in Pediatric Acquired Aplastic Anemia.

Haploidentical family donors have been used as an alternative source in hematopoietic cell transplantation for patients with severe aplastic anemia. We evaluated and compared the outcomes of transplantation in pediatric acquired severe aplastic anemia based on donor type. Sixty-seven patients who underwent transplantation between 1998 and 2017 were included. Fourteen patients received grafts from matched sibling donors, 21 from suitable unrelated donors, and 32 from haploidentical family donors. Ex vivo CD3+ or αß+ T cell-depleted grafts were used for haploidentical transplantation. Sixty-five patients (97.0%) achieved neutrophil engraftment at a median of 11 days. Haploidentical transplantation resulted in significantly faster neutrophil engraftment at a median of 10 days, compared with 14 days in cases of matched sibling donors and 12 days in cases of unrelated donor recipients. Nine patients experienced graft failure, and 5 of 7 who underwent a second transplantation are alive. There was no difference in the incidence of acute or chronic graft-versus-host disease based on donor type. The 5-year overall survival and failure-free survival rates were 93.8% ± 3.0% and 83.3% ± 4.6%, respectively, and there was no significant survival difference based on donor type. The survival outcomes of haploidentical transplantation in patients were comparable with those of matched sibling or unrelated donor transplantation. Optimized haploidentical transplantation using selective T cell depletion and conditioning regimens including low-dose total body irradiation for enhancing engraftment may be a realistic therapeutic option for pediatric patients with severe aplastic anemia.

Recent change in congenital syphilis in Korea: Retrospective 10 year study.

BACKGROUND: This study was conducted to evaluate recent clinical and anthropologic features of neonates with reactive serology for syphilis and their mothers from three institutions in Korea over an 11-year-period. METHOD: The medical records of 20 neonates with reactive serology for syphilis and their mothers at three centers (Kyung Hee University Hospital, Kyung Hee University Hospital at Gangdong, and Korea Electric Power Corporation Hospital) seen between January 2000 and December 2010 were reviewed retrospectively. RESULTS: Among 20 mothers, 16 (80%) were native Korean and four (20%) were foreign-born immigrants. Two mothers (10%) were unmarried. The annual distribution of cases was three (15%) in 2000, one each (5%) in 2005 and 2006, respectively, two each (10%) in 2007 and 2008, respectively, six (30%) in 2009, and five (25%) in 2010. Just over half (55%) occurred across 2009 and 2010. All neonates, by definition, were diagnosed with presumptive congenital syphilis (CS). Among the neonates, four had positive cerebrospinal fluid venereal disease research laboratory test, and three exhibited symptoms and signs. CONCLUSIONS: In three centers in Seoul, Korea, the observed number of CS cases was higher in 2009 and 2010 than in previous years. This finding is consistent with a trend toward increasing prevalence of international marriage and suggests that more meticulous screening of CS is needed.

Cognitive function in childhood epilepsy: importance of attention deficit hyperactivity disorder.

BACKGROUND AND PURPOSE: To determine how cognitive function is related to epilepsy classification and comorbid attention deficit hyperactivity disorder (ADHD) in children with newly diagnosed epilepsy of genetic or unknown etiology. METHODS: The medical records of children aged 6-16 years with newly diagnosed epilepsy of genetic or unknown etiology were reviewed retrospectively. The Korean Education Development Institute-Wechsler Intelligence Scale for Children and the Comprehensive Attention Test were used to evaluate intelligence and attention/executive function, respectively. RESULTS: The data of a total of 149 children, 103 with focal seizures and 46 with generalized seizures, were reviewed. The prevalence of ADHD was 49.2% (59 out of 120 examined patients), and ADHD patients exhibited significantly worse auditory selective attention, flanker test results, and spatial working memory. Patients with generalized seizures exhibited significantly worse auditory selective and sustained attention than patients with focal seizures. In patients with generalized seizures, sustained attention, flanker test findings, and spatial working memory were found to be affected by ADHD, and auditory selective and sustained attention were significantly worse in patients with benign childhood epilepsy with centrotemporal spikes and ADHD than in their counterparts without ADHD. CONCLUSIONS: Cognitive processes are affected by seizure type and comorbid ADHD. Proper characterization of these neuropsychiatric impairments may allow earlier intervention during the disease course.

Effect of paracetamol use on the modification of the development of asthma by reactive oxygen species genes.

BACKGROUND: Recent studies have identified an increase in the prevalence of asthma associated with paracetamol use. OBJECTIVE: To identify the relationship among asthma, biomarkers, genes, and paracetamol use in preschool children. METHODS: We undertook a population-based, cross-sectional survey of 933 preschool children. Asthma status was classified according to medical history and asthmatic symptoms. History of paracetamol use in infancy was recorded. Impulse oscillometry, blood tests for eosinophils and total IgE, and genotyping of NAT2, Nrf2, and GSTP1 polymorphisms by TaqMan assay were conducted. RESULT: Paracetamol use in infancy was associated with an increased risk of treatment for asthma within the previous 12 months. Paracetamol use together with a family history of asthma increased the risk of asthma diagnosis ever, current asthma, and treatment for asthma within the previous 12 months. Gene polymorphisms in NAT2 (rs4271002), Nrf2 (rd6726395), and GSTP1 (rd1695) increased the risk of treatment for asthma within the last 12 months. Eosinophils were significantly elevated in the group with paracetamol use and a family history of asthma; however, the serum total IgE level and IOS did not show any significant difference. CONCLUSION: Paracetamol use in infancy was significantly associated with increased risk of asthma. The association is more significant in genetically susceptible children, related to antioxidant genes, and the effect may be mediated by eosinophilic inflammation.