Childhood-onset autosomal-dominant limb-girdle muscular dystrophy with cardiac conduction block

Abstract

We report childhood‐onset autosomal‐dominant limb‐girdle muscular dystrophy (LGMD) in a Chinese family with complete atrioventricular conduction block in the adult members. Six patients, including 5 men and 1 woman with an age of onset from 3 to 7 years, were affected. The grandfather had exercise intolerance since childhood and complete heart block with pace‐maker placement at age 52. Three siblings had proximal muscle weakness and/or wasting since age 5 and heart block in their 40s. Two grandsons at the ages 7 and 3 showed exercise intolerance, and proximal muscle weakness and wasting. Sinus bradycardia was present in the elder grandson. Muscle enzymes were elevated in 3, particularly in childhood. Muscle biopsies from the proband showed myopathic changes with fatty degeneration, whorled fibers, and rimmed vacuoles. In adult patients, muscle magnetic resonance imaging scans disclosed atrophic changes and fatty degeneration in the gluteal, quadriceps, adductors, hamstrings, gastrocnemius, and soleus muscles, while in child probands the early atrophic changes were seen in the gluteal and hamstrings muscles. We conclude that this distinct family is characterized by childhood‐onset autosomal‐dominant LGMD with heart block and that prevention of sudden death in these patients is important. © 1997 John Wiley & Sons, Inc. Muscle Nerve, 20, 286–292, 1997.

Familial Skeletal Myopathy with Atrioventricular Block.

“…The other patient had atrial paralysis requiring permanent pacing. Fang et al reported familial cases of childhood-onset autosomal-dominant LGMD in a Chinese family with complete AVconduction block in the adults (22). Muscle biopsies from the proband showed myopathic changes with fatty degeneration, whorled fibers and rimmed vacuoles.…”

Autosomal dominant Late-onset Quadriceps Myopathy: Three Patients of a Taiwanese Kindred

“…LGMD 1B and 1C can present with autosomal dominant quadriceps weakness; however, their age of onset is much earlier than those of ADQM (31)(32)(33). Further, joint contractures, cardiac involvement, and mutation in lamin A/C gene, frequently seen in LGMD 1B, were absent in ADQM patients and serum CK levels tend to be very high in LGMD 1C, but are almost normal in ADQM.…”