1. Case Study 86 Leonidas Arvanitis, MD

2. Question 1:
A 2-month-old male presents with severe hypotonia and weakness, cardiac and respiratory failure
He also has a large tongue and feeding difficulties
Describe the histologic findings on the H&E stains
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3. Answer 1:
Marked vacuolation of type 1 and type 2 myofibers

4. Question 2:
Based on the most likely diagnosis what would a PAS stain show?
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5. Answer 2:
The vacuoles are strongly PAS positive

6. Question 3:
Which other histochemical will strongly highlight the vacuoles?

7. Answer 3:
Acid phosphatase
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8. Question 4:
What is your diagnosis?

9. Answer 5:
Pompe's disease

10. Question 6:
Which enzyme is deficient in Pompe’s disease?

11. Answer 6:
Acid maltase
a lysosomal enzyme which is responsible for hydrolyzing maltose, linear oligosaccharides and the outer chains of glycogen to glucose

12. Question 7:
How many clinical subtypes of Pompe’s disease exist?

13. Answer 7:
Severe infantile form
Juvenile-onset form
Adult-onset form

14. Question 8:
What other organs can be affected?

15. Answer 8:
Can involve heart, liver, kidney and CNS

16. Question 9:
What would electron microscopy show?

17. Answer 9:
Vacuolated myofibers with cytoplasmic glycogen accumulation and disruption of myofibrils