Hyper-CK-emia as the sole manifestation of myotonic dystrophy type 2.
A 49-year-old man had an 8-year history of persistent, isolated elevation of serum creatine kinase (hyper-CK-emia) without muscle symptoms, and no electromyographic evidence of myotonia; his muscle biopsy showed features reminiscent of myotonic dystrophy (DM), with morphometric findings consistent with those described in DM type 2 (DM2). Genetic studies excluded mutations in the DM type 1 (DM1) gene, but revealed a CCTG repeat expansion in the ZNF9 gene, which is associated with DM2. Our data suggest that in asymptomatic patients with persistent hyper-CK-emia, DM2 should be considered in the differential diagnosis.
Merlini
Luciano
L
Neuromuscular Unit, Istituti Ortopedici Rizzoli, Bologna, Italy.
Sabatelli
Patrizia
P
Columbaro
Marta
M
Bonifazi
Emanuela
E
Pisani
Valerio
V
Massa
Roberto
R
Novelli
Giuseppe
G
D001706:Biopsy; D003402:Creatine Kinase / Q000097:blood*; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000201:enzymology* / Q000473:pathology; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology; D009154:Mutation / Q000235:genetics; D009223:Myotonic Dystrophy / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology; D016601:RNA-Binding Proteins / Q000235:genetics; D018911:Trinucleotide Repeats / Q000235:genetics; D015854:Up-Regulation / Q000235:genetics
C433227:CNBP protein, human; D016601:RNA-Binding Proteins; D003402:Creatine Kinase