An uncommon case with coexistence of Down syndrome and Duchenne muscular dystrophy

Down syndrome and Duchenne muscular dystrophy are not uncommon hereditary diseases in children. This case report presents a five-year-old male child with Down syndrome who exhibited elevated transaminase levels, hypotonia, proximal muscle weakness, and motor developmental delay. Genetic analysis confirmed a hemizygous duplication in exons 8-18 of the DMD gene, establishing the diagnosis of Duchenne muscular dystrophy. This rare coexistence highlights the importance of evaluating additional genetic disorders, particularly muscular dystrophies, in Down syndrome patients presenting with muscle weakness or elevated transaminase levels. Early diagnosis and a multidisciplinary approach are of critical importance.