title: Grandpa and I have dystrophinopathy?: approach to asymptomatic hyperCKemia.
abstract: This report describes three males from a single kinship, ages 7, 8, and 67 years with clinically asymptomatic dystrophinopathy. The index case was an 8-year-old male evaluated for asymptomatic but persistently elevated serum creatine kinase levels. Muscle biopsy demonstrated a mild myopathy, without necrotic fibers. Immunostaining for dystrophin revealed a slight reduction in sarcolemmal reactivity for the amino terminus of dystrophin. Dystrophin gene analysis revealed a deletion of exon 45 to exon 51. Genetic analysis identified two other affected males (age 7 years and 67 years), as well as four female carriers in the same family. The 7-year-old male had mildly increased creatine kinase levels with normal muscle strength. The 67-year-old grandfather had normal neuromuscular examination and serum creatine kinase levels. Asymptomatic dystrophinopathy in late adulthood is exceptionally rare, and highlights the importance of consideration of dystrophin mutation analysis in patients with hyperCKemia, even in the absence of muscle weakness.
authors.affiliation: Division Neurology, Department of Paediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Canada.
authors.forename: Montri
authors.initials: M
authors.lastname: Saengpattrachai
authors.forename: Peter N
authors.initials: PN
authors.lastname: Ray
authors.forename: Cynthia E
authors.initials: CE
authors.lastname: Hawkins
authors.forename: Alan
authors.initials: A
authors.lastname: Berzen
authors.forename: Brenda L
authors.initials: BL
authors.lastname: Banwell
mesh_terms: D000368:Aged; D002648:Child; D003402:Creatine Kinase / Q000097:blood*; D016189:Dystrophin / Q000235:genetics*; D005091:Exons / Q000235:genetics*; D006801:Humans; D008297:Male; D010375:Pedigree
chemical_list: C484258:DMD protein, human; D016189:Dystrophin; D003402:Creatine Kinase