Frydman et al. (1995) described a 7-month-old boy with gross motor delay and failure to thrive who presented with rhabdomyolysis following an acute asthmatic episode. During hospitalization, the ECG changed from normal sinus rhythm to a type I Wolff-Parkinson-White pattern. Duchenne muscular dystrophy (DMD; 310200) was suspected based on elevated creatine kinase serum levels, muscle biopsy, and family history. The diagnosis was confirmed by molecular analyses which documented a deletion in the dystrophin gene (300377) in the propositus, and in an affected male cousin of his mother. 'Idiopathic' hyperCKemia was found in the propositus, his father, and 5 of his relatives. Frydman et al. (1995) suggested that the unusually early and severe manifestations of DMD in this patient may be related to the coincidental inheritance of a maternal DMD gene and of a paternal gene causing hyperCKemia.

Reference
OMIM: Elevated serum creatine phosphokinase