Congenital Acute Lymphoblastic Leukaemia with Hyperleukocytosis in a Full-Term Neonate: A Case Report

Background: Congenital leukaemia is a rare neonatal malignancy (<1% of childhood leukaemias) that often presents with nonspecific signs such as hepatosplenomegaly, skin lesions, and cytopenias, making diagnosis challenging. Case Presentation: We report a 25-day-old full-term female with fever, multiple subcutaneous nodules, bruising, petechiae, and hepatosplenomegaly. Labs showed extreme hyperleukocytosis, severe anaemia, thrombocytopenia, elevated LDH, and hyperuricemia. Peripheral smear revealed numerous lymphoblasts. Flow cytometry confirmed B-cell precursor ALL without CNS, testicular, or bone involvement. The patient received supportive care and was subsequently referred for chemotherapy but unfortunately died shortly after transfer. Conclusion: Congenital leukaemia should be considered in neonates with unexplained hepatosplenomegaly, skin lesions, and cytopenias. Early hematologic evaluation and immunophenotyping are essential, though prognosis remains poor.