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Lipid myopathy: ETFDH mutations

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Capillaries Degradative Lipid storage Mitochondria Muscle fibers Ultrastructure   Lipid   Mitochondria

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ETFDH Lipid Myopathy: Patterns

Sudan black stain

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H&E stain

Muscle fibers
  Sizes: Varied, Bimodal
  Contain: Vacuoles, Multiple

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VvG stain

Congo Red stain

NADH stain

Sudan black stain

ATPase pH 4.3 stain

ATPase pH 9.4 stain

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ETFDH Lipid Myopathy: Muscle Fiber Pathology

H&E stain

Lipid Storage in Muscle fibers
Lipid Droplets: Large size, varied among muscle fibers

H&E stain

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Gomori trichrome stain

Lipid Storage in Muscle fibers
Lipid Droplets: Large size, varied among muscle fibers

Gomori trichrome stain

Gomori trichrome stain

Gomori trichrome stain

Storage in Muscle fibers
Other storage material may stain red

Gomori trichrome stain

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VvG stain

Lipid Storage in Muscle fibers
Lipid Droplets: Large size, varied among muscle fibers; Some replace entire fibers

VvG stain

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Sudan stain

Lipid Storage in Muscle fibers
Lipid Droplets: Large size, varied among muscle fibers

Sudan stain

Sudan stain

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ATPase pH 4.3 stain

Lipid Storage in Muscle fibers
Lipid Droplets: More & Larger in Type I (Dark) muscle fibers

ATPase pH 4.3 stain

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From: R Schmidt

Lipid droplets
  Many in scattered muscle fiber cytoplasm
  Sarcomeres: Organization is disordered

From: R Schmidt

Lipid droplets
  Many in muscle fiber cytoplasm (Arrow)
  Sarcomeres: Organization is disordered

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From: R Schmidt

Lipid droplets
  In muscle fiber cytoplasm (Arrow): Amid proliferated & closely neighboring mitochondria
  Sarcomeres: Scattered; Organization is disordered

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From: R Schmidt

Lipid droplets & Lipopigment (Arrow)
  In muscle fiber cytoplasm

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ETFDH Lipid Myopathy: Mitochondrial Pathology

Cytochrome oxidase (COX) stain

Cytochrome oxidase (COX) staining
  May be increased or reduced in muscle fibers

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Cytochrome oxidase stain

Cytochrome oxidase (COX) staining
  Increased in some muscle fibers

Cytochrome oxidase stain

SDH stain

ETFDH Mitochondria
  Large & Abundant
  Lipid Droplets: Pink staining
  Proliferation in some muscle fibers & capillaries

SDH stain

SDH stain

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ETFDH Mitochondria
  Varied degress of proliferation among sarcomeres & lipid droplets in different muscle fibers

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ETFDH Mitochondria
  Varied degress of proliferation among sarcomeres in different muscle fibers

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ETFDH Mitochondria
  Increased numbers
  Scattered among sarcomeres (Above) or clustered under sarcolemma(Below)

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ETFDH Lipid Myopathy: Degradation Pathology

Acid phosphatase stain

Lysosomal Pathology
  Muscle fiber cytoplasm & Some small endomysial cells: Stain for Acid phosphatase

Acid phosphatase stain

Acid phosphatase stain

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ETFDH: Autophagic Pathology

LC3 stain

LC3 aggregates in muscle fibers

LC3 stain

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ETFDH Lipid Myopathy: Capillary Proliferation & Pathology

VvG stain

Endomysial Capillaries: Increased numbers & Large

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Alkaline phosphatase stain

Endomysial Capillaries: Alkaline Phosphatase staining Increased

Alkaline phosphatase stain

Endomysial Capillaries: Alkaline Phosphatase staining Increased

Alkaline phosphatase stain

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Endomysial Capillaries: Increased numbers & Large

UEAI stain

UEAI stain

Endomysial Capillaries: Greatly increased numbers & Large size

UEAI stain

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Sudan stain

Lipid storage in Vessels
  Intermediate-sized & Endomysial capillaries (Arrows)

Sudan stain

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Endomysial Capillaries
  Mitochondrial Proliferation (Dark staining; Arrow)
  There is also mitochondrial proliferation in some muscle fibers

SDH stain

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Return to: Pathology index

3/22/2021