Caveolin-associated myopathy: three cases with muscle rippling and a literature review / 中华神经科杂志

ABSTRACT

Objective To summarize the clinical , pathological and genetic characteristics of three patients with caveolin-3 associated myopathy and review the literatures .Methods The clinical data of three patients with caveolin-3 associated myopathy were investigated .With informed consent , we performed muscle biopsy and genetic analysis of CAV 3 and PTRF genes.Results All the three patients presented with percussion/pressure-induced rapid contraction , percussion-induced muscle mounding and mechanically induced muscle rippling.Besides, case 1 had weakness and atrophy of hand muscles .Case 2, who manifested with muscle hyperexcitability at onset , developed weakness and atrophy of distal part of lower limbs.Case 3 showed normal muscle strength and tone .All of them had myalgia or tenderness .Muscle biopsy revealed mild myogenic changes in two patients and a muscular dystrophic pattern in one . Immunohistochemical staining of caveolin-3 revealed an even deficiency in case 1 and a mosaic deficiency in cases 2 and 3.Gene analysis revealed a missense mutation ( c.80G>A, p.R27Q) in CAV3 gene of case 1. No mutations were identified in cases 2 and 3.Conclusions There is phenotypic variability in patients with caveolin-associated myopathy , including limb-girdle syndrome , rippling muscle disease , distal myopathy , muscle hypertrophy , idiopathic hyperCKemia and cardiomyopathy .Muscle biopsy and caveolin-3 staining should be performed for the above patients with muscle rippling .