ACID MALTASE DEFICIENCY: INFANT & EARLY CHILDHOOD ONSET

H & E stain

Vacuoles in many muscle fibers Some muscle fibers are enlarged Cytoplasm is replaced by clear or purple storage material Other muscle fibers have moderate-sized clear vacuoles

Gomori trichrome stain	Gomori trichrome stain

NADH-stained membranes are displaced by storage material
NADH stain	NADH stain

PAS-stained muscle fibers Diffusely increased staining in fibers	ATPase stained muscle fibers Remaining intact fibers are mostly type 2
PAS stain	ATPase pH 9.4 stain

Acid phosphatase-stained muscle fibers Increased staining of muscle fiber cytoplasm. Few acid phosphatase positive granules (Right)
Acid phosphatase stain	Acid phosphatase stain

Earlier stage: Most glycogen storage is in membrane bound structures

Later stage: More glycogen storage is cytoplasmic