IBM3: Adult; MYH2

H&E stain
Fiber sizes: Marked variation; Hypertrophy & Atrophy
Internal nuclei: Many fibers
Small fibers: Rounded; Some large pyknotic nuclear clumps
Large fibers: Partial fusion

H&E stain

H&E stain
Muscle fiber pathology
Internal nuclei
Partial fusion
Pyknotic nuclear clumps

Congo red stain

Congo red stain
Vacuoles: Contain basophilic granular debris

Congo red stain

Congo red stain
Nuclei: Large; Internal

ATPase pH 9.4 stain
Type 2 fiber predominance: Many fibers are 2C

ATPase pH 4.3 stain

NADH stain
Internal architecture: Some small fibers are dark; Large fibers are irregular
Return to Neuromuscular
Return to MYH2