"Rimmed vacuole myopathy" sparing the quadriceps. A unique disorder in Iranian Jews.

Nine cases from 4 different Iranian-Jewish families presented with generalized muscular weakness. Quadriceps muscle was the only leg muscle which retained its normal power and function even in advanced cases. Biopsies from severely involved muscles revealed a typical "rimmed vacuole myopathy" while the quadriceps and deltoid showed minimal changes. CK levels were normal or moderately elevated and the EMG pattern suggested an underlining neurogenic disorder. The possible neurogenic character of this autosomal recessive disorder is discussed with relevance to the rimmed vacuoles.