Disseminated MRSA and Myelokathexis Preceding AML with t(8;21) and ASXL1 Mutation

Area of Science:

• Hematology
• Pediatric Oncology
• Molecular Genetics

Background:

• Pediatric acute myeloid leukemia (AML) is a diverse cancer where molecular genetics significantly impact prognosis.
• While t(8;21) AML is typically considered favorable, concurrent mutations like ASXL1 can lead to poorer outcomes.
• Prolonged cytopenias and recurrent infections can precede overt AML diagnosis, posing diagnostic challenges.

Purpose of the Study:

• To report a complex case of pediatric AML with an unusual presentation.
• To illustrate the diagnostic difficulties in identifying AML preceded by cytopenia and infection.
• To emphasize the prognostic significance of ASXL1 mutations in t(8;21) AML and guide treatment decisions.

Main Methods:

• Case report of a 13-year-old boy with recurrent fever, pancytopenia, and disseminated infections.
• Initial investigations included immunological evaluation and bone marrow examination showing myelokathexis.
• Subsequent relapse led to diagnosis of AML with t(8;21), monosomy Y, del(9q), and ASXL1 mutation confirmed by bone marrow biopsy and peripheral smear analysis.

Main Results:

• The patient initially presented with symptoms mimicking immune dysfunction (myelokathexis) but was ultimately diagnosed with AML.
• The confirmed AML harbored both the favorable t(8;21) translocation and the high-risk ASXL1 mutation.
• The patient achieved remission with chemotherapy, but hematopoietic stem cell transplantation (HSCT) was recommended due to high-risk molecular features.

Conclusions:

• Unexplained cytopenia and infection in children warrant vigilant monitoring and comprehensive genomic profiling.
• The ASXL1 mutation in this case conferred high-risk biology, underscoring the need for HSCT in first remission for such patients.
• Integrating molecular risk factors is crucial for developing individualized treatment strategies in pediatric AML.