Poor response of anti-SRP-positive idiopathic immune myositis to B-cell depletion

Abstract
Sir, Antibodies to signal recognition particles (SRPs), cytoplasmic proteins involved in the recognition and targeting of signals to the endoplasmic reticulum, were first reported in association with polymyositis (PM) in a 50-year-old woman by Reeves et al. in 1986 [1]. We present our experience of the difficulty in treating two patients with anti-SRP-positive myopathy.