Hereditary neuromuscular diseases are a common cause of persistent hyperCKemia. Duchenne and Becker muscular dystrophies (DMD, DMB), linked to mutations in the DMD gene, are the most common in boys. They can also affect girls, but the proportion of carriers of DMD gene abnormalities that are symptomatic (skeletal muscle and / or heart) remains unclear.
A team conducted a study with 14 patients aged 1 to 12 years referred to the pediatric ward of a hospital in Nishinomiya (Japan) for elevation of CKemia for more than a month:
- the CK level was between 740 and 21,944 IU / L,
- 7 patients were symptomatic (muscle weakness, myalgia, motor or language delay),
- none had any abnormalities on the cardiac ultrasound,
- DMD gene analysis revealed abnormalities in 5 symptomatic and 3 asymptomatic girls,
- for patients whose analysis of the DMD gene was negative, the work-up (NGS and sometimes muscle biopsy) found one case of dermatomyositis and another of symptomatic sarcoglycanopathy (LGMDR4), and one case of asymptomatic calpainopathy (LGMDR1).