Figure 1

Pathological characteristics of sporadic inclusion body myositis (s-IBM). A-C: Case 1, atrophic muscle fibers were angular, irregular, and round, with muscle fiber hypertrophy, HE staining, ×100 (A); Fimbriated cavity and inclusion bodies (blue arrows), HE staining, ×200 (B); Sand-like particles (inclusion bodies) (blue arrows), HE staining, ×400 (C). D ~ F: Case 2, round Fimbriated cavities in the atrophic muscle fibers, with sand-like inclusion bodies in which (blue arrows), HE staining, ×400 (D); Red particles of inclusion bodies in fimbriated cavities (yellow arrows), Gomori staining, ×400 (E); Nonnecrotic muscle fibers infiltrated by monocytes (blue arrows), HE staining, ×200 (F). G ~ H: Case 3, Focal inflammatory infiltration (green arrows) and fimbriated cavities showed in several muscle fibers (blue arrows), HE staining, ×100 (G); Round fimbriated cavities in atrophic muscle fibers, with gross particles of inclusion bodies in which (blue arrows), HE staining, ×400 (H).