Figure 3.

Histological and histochemical (a, b and c) findings in m. gastrocnemius biopsy of a patient carrying a p.Cys30071Arg TTN mutation (family B). Prominent structural changes with variation of fiber size and areas of fibrofatty tissue replacement; the majority of fibers harbor collections of cytoplasmic bodies along with large diffuse polymorphic accumulations of material (a). Some fibers contain rimmed vacuoles (arrows in b). Fiber regions occupied by the cytoplasmic bodies are devoid of oxidative activity (c). Resin semithin section shows typical cytoplasmic bodies (d). Stains: a: modified trichrome; b: H&E; c: NADH; d: semithin section stained with toluidine blue.