Non-Down syndrome pediatric acute megakaryoblastic leukemia (AMKL) may be classified according to the presence of recurrent genetic abnormalities with prognostic relevance. In this case study, we report on a girl with AMKL, 32 months old at the time of diagnosis, in whom we confirmed the presence of the cryptic, poor prognosis NUP98::KDM5A fusion. The patient achieved complete remission (CR) with the first course of chemotherapy, underwent haploidentical family donor hematopoietic stem cell transplantation (HSCT) without event, but relapsed 5 months after HSCT. Through this case report, we emphasize the good initial response to chemotherapy, and the early relapse despite undergoing HSCT in first CR. We review the limited literature on NUP98::KDM5A (+) pediatric AML, and underscore the need for further study to improve the outcome of patients with this rare AML subtype.

Essential thrombocytosis (ET) is a rare myeloproliferative disease in children, and there are few standard man‑ agement guidelines. We herein report a case series of 10 pediatric patients with ET diagnosed at our institution over a period of 13 years. All patients fulfilled the World Health Organization diagnostic criteria for ET, and none harbored the canonical ET mutations JAK2 V617F, CALR, or MPL. Overall, 7 of the 10 patients received treatment for ET, and during follow-up, 3 of these 7 patients discontinued cytoreductive therapy. No patient experienced hemorrhagic or thrombotic complications. Our case series emphasizes that the genetic features of pediatric ET may differ signifi‑ cantly from those of adult ET, and that treatment cessation is a possibility for some patients.

Non-Down syndrome pediatric acute megakaryoblastic leukemia (AMKL) may be classified according to the presence of recurrent genetic abnormalities with prognostic relevance. In this case study, we report on a girl with AMKL, 32 months old at the time of diagnosis, in whom we confirmed the presence of the cryptic, poor prognosis NUP98::KDM5A fusion. The patient achieved complete remission (CR) with the first course of chemotherapy, underwent haploidentical family donor hematopoietic stem cell transplantation (HSCT) without event, but relapsed 5 months after HSCT. Through this case report, we emphasize the good initial response to chemotherapy, and the early relapse despite undergoing HSCT in first CR. We review the limited literature on NUP98::KDM5A (+) pediatric AML, and underscore the need for further study to improve the outcome of patients with this rare AML subtype.

Essential thrombocytosis (ET) is a rare myeloproliferative disease in children, and there are few standard man‑ agement guidelines. We herein report a case series of 10 pediatric patients with ET diagnosed at our institution over a period of 13 years. All patients fulfilled the World Health Organization diagnostic criteria for ET, and none harbored the canonical ET mutations JAK2 V617F, CALR, or MPL. Overall, 7 of the 10 patients received treatment for ET, and during follow-up, 3 of these 7 patients discontinued cytoreductive therapy. No patient experienced hemorrhagic or thrombotic complications. Our case series emphasizes that the genetic features of pediatric ET may differ signifi‑ cantly from those of adult ET, and that treatment cessation is a possibility for some patients.

Non-Down syndrome pediatric acute megakaryoblastic leukemia (AMKL) may be classified according to the presence of recurrent genetic abnormalities with prognostic relevance. In this case study, we report on a girl with AMKL, 32 months old at the time of diagnosis, in whom we confirmed the presence of the cryptic, poor prognosis NUP98::KDM5A fusion. The patient achieved complete remission (CR) with the first course of chemotherapy, underwent haploidentical family donor hematopoietic stem cell transplantation (HSCT) without event, but relapsed 5 months after HSCT. Through this case report, we emphasize the good initial response to chemotherapy, and the early relapse despite undergoing HSCT in first CR. We review the limited literature on NUP98::KDM5A (+) pediatric AML, and underscore the need for further study to improve the outcome of patients with this rare AML subtype.

Essential thrombocytosis (ET) is a rare myeloproliferative disease in children, and there are few standard man‑ agement guidelines. We herein report a case series of 10 pediatric patients with ET diagnosed at our institution over a period of 13 years. All patients fulfilled the World Health Organization diagnostic criteria for ET, and none harbored the canonical ET mutations JAK2 V617F, CALR, or MPL. Overall, 7 of the 10 patients received treatment for ET, and during follow-up, 3 of these 7 patients discontinued cytoreductive therapy. No patient experienced hemorrhagic or thrombotic complications. Our case series emphasizes that the genetic features of pediatric ET may differ signifi‑ cantly from those of adult ET, and that treatment cessation is a possibility for some patients.

Non-Down syndrome pediatric acute megakaryoblastic leukemia (AMKL) may be classified according to the presence of recurrent genetic abnormalities with prognostic relevance. In this case study, we report on a girl with AMKL, 32 months old at the time of diagnosis, in whom we confirmed the presence of the cryptic, poor prognosis NUP98::KDM5A fusion. The patient achieved complete remission (CR) with the first course of chemotherapy, underwent haploidentical family donor hematopoietic stem cell transplantation (HSCT) without event, but relapsed 5 months after HSCT. Through this case report, we emphasize the good initial response to chemotherapy, and the early relapse despite undergoing HSCT in first CR. We review the limited literature on NUP98::KDM5A (+) pediatric AML, and underscore the need for further study to improve the outcome of patients with this rare AML subtype.

Purpose: Glycated hemoglobin (HbA1c) as a glycemic index may have limited value in pediatric patients with acute leukemia as they often present with anemia and/or pancytopenia. To address this issue, we evaluated the usefulness of glycated albumin (GA) as a glycemic monitoring index in pediatric patients with acute leukemia. Methods: Medical records of 25 patients with type 2 diabetes mellitus (T2DM), 63 patients with acute leukemia, and 115 healthy children from Seoul St. Mary's Hospital, The Catholic University of Korea, were retrospectively investigated for serum GA, HbA1c, and fasting blood glucose (FBG) levels, along with demographic data. Results: GA, HbA1c, and FBG levels did not differ between the control and acute leukemia groups. In the T2DM group, positive correlations were observed among GA, HbA1c, and FBG (P<0.01). Although GA level was not associated with the HbA1c level in the control group, GA and HbA1c levels showed a positive correlation in the acute leukemia group (P=0.045). Regression analysis revealed GA and HbA1c levels to be positively correlated in the acute leukemia and T2DM groups even after adjusting for age, sex, and body mass index z-score (P=0.007, P<0.01). Conclusion GA may be a useful complementary parameter to HbA1c for glycemic monitoring in pediatric patients with acute leukemia, similar to its use in patients with T2DM.

Tyrosine kinase (TK) inhibitors are most common used to treat chronic myeloid leukemia (CML). Several studies describe a range of adverse effects of TK inhibitors on the kidney in adult patients, including nephrotic syndrome. However, there are only a few pediatric case reports on TK inhibitor-associated nephrotic syndrome. We report a case of nephrotic syndrome associated with dasatinib, a type of TK inhibitor, in a child who suffered from both the underlying idiopathic nephrotic syndrome and CML. A 14-year-old Korean boy was diagnosed with steroid dependent nephrotic syndrome at 4 years old and CML at 11 years old. He developed a relapse of nephrotic syndrome after treatment with TK inhibitors, especially dasatinib, which he used for four months. Despite receiving steroid pulse therapy due to his underlying steroid dependent nephrotic syndrome, his proteinuria did not respond. He discontinued dasatinib medication due to the possibility to dasatinib induced nephrotic syndrome.After one week, his nephrotic syndrome improved. The case is important because if a CML patient that has been on a TK inhibitor develops a newly onset nephrotic range proteinuria, TK inhibitor-induced nephrotic syndrome should be included in the differential diagnosis.

Purpose: This study aimed to investigate the clinical factors associated with bone mineral density (BMD) among children and adolescents with osteoporosis secondary to treatment for underlying clinical conditions. Methods: We retrospectively reviewed the medical records of patients aged 10–18 years and evaluated them for lumbar spine BMD (LSBMD) after treatment for underlying diseases, including hemato-oncologic, rheumatologic system, and inflammator y bowel diseases. LSBMD measured by dual-energy x-ray absorptiometry (DXA) performed from March 2019 to March 2021 was evaluated. We analyzed 117 patients who underwent initial DXA after treatment for underlying diseases. Results: Subjects in this study had multiple underlying diseases: hemato-oncologic (78.6%), rheumatologic (11.1%), and inflammatory bowel diseases (10.3%). There was no significant association between the z-score and bone metabolic markers (P>0.05). However, higher cumulative glucocorticoid (GC) dose significantly reduced LSBMD z-score (P=0.029). Moreover, the association between cumulative dose of GC and initial z-score of LSBMD was significant in logarithmic regression analysis (P=0.003, R2=0.149). GC accumulation was a significant risk factor for vertebral fracture when the initial BMD was evaluated after treatment (P=0.043). Bone metabolic markers did not significantly influence the risk of vertebral fracture. Conclusion Initial bone mass density of the lumbar spine evaluated after long-term GC use for underlying diseases is a predictor of further vertebral fractures.