In the original article by Pestronk et al, all 11 patients had a skin rash, muscle weakness, perifascicular atrophy with mitochondrial changes in muscle fibers, and capillary damage with Ulex lectin staining.12 In 7 patients, C5b-9 complement deposition in a focal, punctate, capillary-like pattern in the endomysium was observed within areas of perifascicular atrophy. This evidence concerns the gene C5 and exanthem.