FA Lysosomal and Glycogen Storage Diseases Flashcards
What is the inheritance of Glucose-6-phosphatase deficiency
Auto Recessive
What is the likely diagnosis for an 6m old with fasting hypoglycemia, enlarged abdomen, seizures, and increased serum triglycerides?
Von Gierke Disease: Glucose-6-phosphatase def. The enlarged abdomen is from hepatomegaly.
What would serum levels of glucose, lactate, triglycerides, and uric acid be in a patient with Von Gierke Disease? Enzyme def?
Glucose-6-phosphatase. Fasting hypoglycemia, increased lactate, TGs, and uric acid.
Management for Glucose-6-phosphatase deficiency
Frequent oral glucose/cornstarch. Avoid Fructose/Galactose.
What is the inheritance of Lysosomal alpha-1,4-glucosidase deficiency? Other names for this enzyme?
Auto Recessive. Other names for alpha glucosidase are acid maltase and Acid alpha-glucosidase
What are symptoms of Glucose-6-phosphatase deficiency?
Fasting hypoglycemia, hepatomegaly, seizures, increased serum triglycerides, lactate, and uric acid.
What is likely diagnosis for an infant presents with enlarged cardiac silhouette, lethargy, floppy limbs, and poor feeding.
Pompe Disease. Acid alpha-glucosidase Deficiency.
What are classic symptoms of Pompe Disease? Enzyme deficiency?
Cardiomegaly, Hypertrophic cardiomyopathy (Pompe trashes the Pump), exercise intolerance (in older kids), hypotonia in infants (floppy baby), lethary. Presents similar to other glycogen storage disorders but cardiac signs help with ddx.
What are classic biopsy findings of muscle from a kid with pompe disease? What is the deficient enzyme in pompe?
Lysosomal alpha-1,4-glucosidase. Enlarged lysosomes with glycogen build up, appears as clear inclusions filling myocytes.
What enzyme deficiency is associated with Cori Disease? What disease is Cori a milder form of? Inheritance pattern?
Debranching enzyme deficiency, also called alpha-1,6,-glucosidase. Auto Recessive. Milder form of Von Gierke Disease (Glucose-6-phosphatase deficiency)
Is gluconeogenesis intact in Cori Disease? What are levels of lactate?
Yes, normal levels of lactate. Lactate levels increased in Von Gierke Disease.
Most likely lysosomal/glycogen storage disease diagnosis for an 11 y/o female with muscle pain, coffee colored urine, and arrhythmia after playing a soccer game.
McArdle Disease: Skeletal muscle glycogen phosphorylase deficiency (myophosphorylase)
Inheritance pattern for McArdle Disease? Deficient enzyme?
Auto recessive. Skeletal muscle glycogen phosphorylase.
What are typical blood glucose levels of a patient with McArdle Disease?
Usually normal
Are there any options to manage McArdle Disease?
B6=Pyridoxime
What do all Glycogen storage diseases have in common?
Accumulation of Glycogen within cells
Accumulation of what is seen in this cell?
Glucocerebroside d/t lack of Beta-glucosidase (Glucocerebrosidase). Gaucehr cells are “lipid laiden macrophages resembling “crumpled tissue paper””
Looking at this liver sample from a 5m old kid. What are you thinking (besides, “I hate histology and it all looks pink and purpkle)
These are foamy macrophages. “Foam macrophages” is FA’s buzz word for Niemann-Pick disease. these cells also look like the lipid-laiden macrophages in liver from a patient with Gaucher.
Light microscopy and EM have the corresponding findings from an infant with progressive neurodegereration. What disease are these findings associated with? What is accumulating in the cells?
Light microscopy shows neurons with large lipid vacuoles while the EM shows “onion skinning” lysosomes. Findings are consistent with the accumulation of GM2 Ganglioside d/t deficient Hexosaminidase (Tay-Sachs)
