Ei Mon Swe

Consultant Pediatrician, Childrens Hospital, Naypyitaw, Myanmar

Abstract Title:

A Rare Case of Pediatric Acute Myeloid Leukemia (AML) with Complex Hyperdiploid Karyotype and Early Relapse: A Case Report

Biography:

Dr. Ei Mon Swe is a Consultant Pediatrician currently practicing at the Children’s Hospital in Naypyitaw, Myanmar. She obtained her MSc degree in 2016 and achieved her MRCPCH (Membership of the Royal College of Pediatrics and Child Health) in 2024. Her current professional focus is on improving the outcomes for critically ill pediatric patients, particularly those with complex hematological malignancies, and she is committed to advocating for enhanced diagnostic and therapeutic resources in her region.

Research Interests:

Introduction: Pediatric Acute Myeloid Leukemia (AML) with complex hyperdiploid karyotype (50 or more chromosomes) is a rare subtype, occurring in only about 6% of childhood AML cases. These cytogenetic abnormalities are frequently associated with poor prognosis, early relapse, and limited therapeutic options. Case Summary: An 18-month-old girl with no prior medical history presented with one month of prolonged fever, pallor, and a febrile convulsion. Initial labs showed leukocytosis (WBC 27.7 × 10³/µL), anemia (Hb 6.8 g/dL), thrombocytopenia (platelets 56 × 10³/µL), and peripheral blasts (32%). Bone marrow flow cytometry showed 12% blasts with a myeloid phenotype, positive for CD34, CD7, CD117, HLA-DR, CD13, and MPO. Karyotyping revealed a complex hyperdiploid result: 51,XX,add(7)(p22),+8,+11,+14,+21,+22(12)/46,XX(8).

Treatment & Outcomes: The patient achieved a morphological complete remission (CR) with 3% blasts after two cycles of cytarabine and daunorubicin (induction). However, an early relapse occurred one month after completing three cycles of high-dose cytarabine (HIDAC) consolidation. She poorly tolerated the subsequent salvage regimen (PET), requiring multiple transfusions and intensive supportive care. The course was complicated by recurrent febrile neutropenia, infections (including right-sided lower motor neuron facial palsy due to otitis media and mastoiditis), protein-energy malnutrition (PEM), hypokalemia, and transfusion-dependent cytopenias. Discussion: Complex hyperdiploidy with structural abnormalities, such as add(7)(p22), is associated with chemoresistance and poor outcomes. Salvage treatment options are limited in low-resource settings where stem cell transplantation and novel agents (e.g., venetoclax, monoclonal antibodies) are unavailable. This case highlights the challenges of managing relapsed high-risk AML in developing countries, emphasizing the importance of infection control, nutritional support, multidisciplinary care, and transparent communication with families.

Conclusion & Key Learnings: The presence of a complex hyperdiploid karyotype represents a high-risk biology with likely chemoresistance, leading to early relapse. This case underscores the critical need for a multidisciplinary approach and clear, family-centered communication when managing high-risk, relapsed pediatric AML in resource-limited settings. Early recognition, risk stratification, and access to advanced therapies are critical for improving outcomes.