Chronic myeloid leukaemia in a child with mucopolysaccharidosis type VI: diagnostic and management challenges.

A child presented with progressive abdominal swelling, pallor and longstanding skeletal and facial abnormalities. Examination revealed hepatosplenomegaly, coarse facies, joint stiffness and cardiac murmurs. Investigations showed hyperleucocytosis with BCR-ABL1 positivity confirming chronic myeloid leukaemia, while radiological and echocardiographic findings supported a clinical diagnosis of mucopolysaccharidosis type VI (MPS VI). The coexistence of these two rare disorders created diagnostic and management challenges, particularly as urinary glycosaminoglycan testing was inconclusive and enzyme assays were unavailable. The patient was stabilised with hydroxyurea and subsequently commenced on imatinib, achieving haematological remission, while supportive measures addressed the multisystem complications of MPS VI. This case highlights the need for vigilance in recognising malignancy in children with rare genetic disorders, the limitations of confirmatory testing in low-resource settings and the importance of multidisciplinary, individualised care when treatments for one condition may complicate the other.