Spectrum of Neuromuscular Disorders With HyperCKemia From a Tertiary Care Pediatric Neuromuscular Center

Elevated creatine kinase is a useful screening test in the diagnostic workup of patients with neuromuscular disorders. We did a retrospective study of children with hyperCKemia (>175 IU/L) who were followed in the neuromuscular program of a tertiary care pediatric center from 2005 to 2016. Patients with hyperCKemia were divided into 2 groups: myopathic and nonmyopathic. Within the myopathic group, there were 3 arbitrary subgroups based on creatine kinase values: A (creatine kinase >10 times normal), B (creatine kinase 5-10 times normal), and C (creatine kinase 1-5 times normal). The 3 major categories of myopathies across all the subgroups were muscular dystrophies (commonest) followed by metabolic myopathies and inflammatory myopathies. Among the nonmyopathic causes of hyperCKemia, spinal muscular atrophy was the commonest. Muscular dystrophies should be considered in children with hyperCKemia, muscle weakness, or calf hypertrophy, and metabolic myopathies to be considered in children with recurrent rhabdomyolysis.