Korean J Pediatr.  2012 Sep;55(9):350-353. 10.3345/kjp.2012.55.9.350.

A case of Becker muscular dystrophy with early manifestation of cardiomyopathy

• Doo KH
• Ryu HW
• Kim SS
• Lim BC
• Hwang H
• Kim KJ
• Hwang YS
• Chae JH

• KMID: 2284394
• DOI: http://doi.org/10.3345/kjp.2012.55.9.350

Abstract

An 18-year-old boy was admitted with chest discomfort, nausea, and dyspnea at rest. At the age of 3 years, he underwent muscle biopsy and dystrophin gene analysis owing to an enlarged calf muscle and elevated serum kinase level (6,378 U/L) without overt weakness; based on the results, Becker muscular dystrophy (BMD) was diagnosed. The dystrophin gene showed deletion of exons 45 to 49. He remained ambulant and could step upstairs without significant difficulties. A chest roentgenogram showed cardiomegaly (cardiothoracic ratio, 54%), and his electrocardiogram (ECG) showed abnormal ST-T wave, biatrial enlargement, and left ventricular hypertrophy. The 2-dimensional and M-mode ECGs showed a severely dilated left ventricular cavity with diffuse hypokinesis. The systolic indices were reduced, including fractional shortening (9%) and ejection fraction (19%). Despite receiving intensive medical treatment, he died from congestive heart failure 5 months after the initial cardiac symptoms. We report a case of BMD with early-onset dilated cardiomyopathy associated with deletion of exons 45 to 49. Early cardiomyopathy can occur in BMD patients with certain genotypes; therefore, careful follow-up is required even in patients with mild phenotypes of BMD.

Keyword

Becker muscular dystrophy; Early onset cardiomyopathy; Genotype

MeSH Terms

Adolescent
Biopsy
Cardiomegaly
Cardiomyopathies
Cardiomyopathy, Dilated
Dyspnea
Dystrophin
Electrocardiography
Exons
Genotype
Heart Failure
Humans
Hypertrophy, Left Ventricular
Muscles
Muscular Dystrophy, Duchenne
Nausea
Phenotype
Phosphotransferases
Thorax
Dystrophin
Phosphotransferases