Incidental Detection of Acute Leukemia During Genetic Evaluation of Neurodevelopmental Disorder in a Pediatric Clinic: A Case Report.

A previously healthy 5-year-old boy presented to pediatric neurology for evaluation of recurrent migraine headaches with associated anxiety. Neurologic imaging was unremarkable, but clinical features consistent with autism spectrum disorder were noted. As part of standard-of-care ASD evaluation, SNP chromosomal microarray (CMA) on peripheral blood revealed a hypodiploid genome (∼35 chromosomes), suspicious for leukemia. Prompt notification led to repeat blood testing showing ∼30% circulating blasts. A diagnosis of acute leukemia was made, and constitutional CMA on buccal DNA showed a normal diploid male karyotype. This case illustrates the potential for ASD genetic testing to yield critical, incidental systemic findings and underscores the importance of rapid follow-up and interdisciplinary care.