A Carrier of Duchenne Muscular Dystrophy in an 8-month-old Girl

A Carrier of Duchenne Muscular Dystrophy in an 8-month-old GirlDuchenne muscular dystrophy (DMD) is the most common and severe form of childhood muscular dystrophy.Females are affected in rare cases because of its' Xlinked, recessive inheritance.A small number of female DMD carriers have muscle weakness to some extent.A healthy 8-month-old girl was brought to our tertiary center because of the elevated serum liver enzyme (aspartate aminotransferase (AST): 986 IU/mL, alanine aminotransferase (ALT): 1,126 IU/mL), that was first noted 1 month ago when she was hospitalized for an acute respiratory infection.Follow-up her serum liver enzyme, AST and ALT level remained increased to 613 and 1,049 IU/mL, respectively without serologic evidence of viral hepatitis.Serum creatinine kinase (CK) level was highly elevated to 5,245 U/L.She showed normal development.Pseudohypertrophy of bilateral calf muscle was not observed, and Gowers' sign was not seen because of her young age.Electromyography and cardiac echocardiography showed no abnormal findings.A multiplex ligation-dependent probe amplification confirmed the heterozygote deletion mutation of DMD gene in exon 10-17.The result of karyotyping was normal 46,XX.She was diagnosed as an asymptomatic DMD carrier.Female carriers are usually asymptomatic but may have an elevated serum CK and/ or mild calf hypertrophy.A girl with persistent elevated liver enzyme and CK level should be evaluated for the neuromuscular disease including DMD, despite her normal motor activity.