Muscle MRI findings in patients with an apparently exclusive cardiac phenotype due to a novel LMNA gene mutation.
The case of a family in which several members displayed conduction defects inherited as a dominant trait is reported. The proband was a young woman with a 1st degree atrio-ventricular block and high serum creatine kinase. Several members of the family featured cardiologic symptoms. All adult family members were clinically evaluated and blood tests including serum creatine-kinase levels, standard and Holter ECG, echocardiogram and muscle MRI were performed. LMNA gene analysis was carried out and a novel missense mutation consisting in substitution of exon 4 c.799 T/C, p.Tyr267His was revealed. The mutation was present in seven family members, five of whom displayed cardiac defects alone with no involvement of the skeletal muscle. In all mutated individuals muscle MRI featured a pattern of skeletal muscle involvement similar to that observed in autosomal dominant Emery Dreifuss muscular dystrophy, suggesting that even patients bearing a LMNA gene mutation associated to an apparently selective cardiac phenotype may present subclinical skeletal muscle involvement.
Carboni
Nicola
N
Neuromuscular Unit, Dipartimento di Scienze Cardiovascolari e Neurologiche, University of Cagliari, Cagliari, Italy. nikola.carboni@tiscali.it
Mura
Marco
M
Marrosu
Giovanni
G
Cocco
Eleonora
E
Ahmad
Mohammad
M
Solla
Elisabetta
E
Mateddu
Anna
A
Maioli
Maria Antonietta
MA
Marini
Stefano
S
Nissardi
Vincenzo
V
Frau
Jessica
J
Mallarini
Giorgio
G
Mercuro
Giuseppe
G
Marrosu
Maria Giovanna
MG
D000328:Adult; D003402:Creatine Kinase / Q000097:blood; D004252:DNA Mutational Analysis; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D005192:Family Health; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000150:complications / Q000235:genetics* / Q000473:pathology*; D006801:Humans; D034904:Lamin Type A / Q000235:genetics*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D018482:Muscle, Skeletal / Q000473:pathology; D020389:Muscular Dystrophy, Emery-Dreifuss / Q000150:complications / Q000235:genetics; D009154:Mutation; D009206:Myocardium / Q000473:pathology*; D010641:Phenotype
D034904:Lamin Type A; D003402:Creatine Kinase