Myopathy With Anti Signal Recognition Particle Antibody

ABSTRACT

Myopathies associated with anti-signal-recognition particle (SRP) antibodies usually present with severe muscle weakness and exhibit necrotizing myopathy with little inflammation pathologically. Here we report a case of a 61-year-old man who presented with subacute progressive proximal muscle weakness, dysarthria, and dysphagia. Although polymyositis was expected clinically, muscle biopsy revealed myopathic changes with degenerating fibers without definite inflammation. Further laboratory study revealed that the patient was positive for anti-SRP antibodies.