A Japanese male with a novel ANO5 mutation with minimal muscle weakness and muscle pain till his late fifties

Neuromuscul Disord. 2017 May;27(5):477-480. doi: 10.1016/j.nmd.2017.01.012. Epub 2017 Jan 18.

Abstract

Limb girdle muscular dystrophy type 2L (LGMD2L) is an adult-onset slowly progressive muscular dystrophy associated with anoctamin 5 (ANO5) gene mutation, mainly reported from Northern and Central Europe. We report the case of a Japanese male patient with a novel homozygous mutation of c.2394dup, p.Arg799Thrfs in ANO5 gene, the second patient in the Asian population. He had had marked elevation of creatine kinase (CK) level for more than 10 years with minimal muscular symptoms consisting of muscle stiffness and occasional cramps, preceding the onset of proximal limb weakness. Calf hypertrophy and selective fatty replacement of the adductor magnus and gastrocnemius muscles were prominent clinical and muscle imaging features. This case suggests that LGMD2L may affect a broader population than has been previously thought, physicians should consider the possibility of ANO5 mutation even in patients showing elevated CK level with no apparent muscle weakness but muscle stiffness or cramps.

Keywords: Anoctamin 5; Calf hypertrophy; HyperCKemia; Limb girdle muscular dystrophy type 2L; Non-European population.

Publication types

  • Case Reports

MeSH terms

  • Age of Onset
  • Anoctamins / genetics*
  • Asian People / genetics
  • Homozygote
  • Humans
  • Japan
  • Male
  • Middle Aged
  • Muscle Weakness / diagnostic imaging
  • Muscle Weakness / genetics*
  • Muscle Weakness / pathology
  • Muscle Weakness / physiopathology
  • Muscle, Skeletal / pathology
  • Muscular Dystrophies, Limb-Girdle / diagnostic imaging
  • Muscular Dystrophies, Limb-Girdle / genetics*
  • Muscular Dystrophies, Limb-Girdle / pathology
  • Muscular Dystrophies, Limb-Girdle / physiopathology
  • Mutation*
  • Myalgia / diagnostic imaging
  • Myalgia / genetics*
  • Myalgia / pathology
  • Myalgia / physiopathology

Substances

  • ANO5 protein, human
  • Anoctamins