2G- Inborn Errors of Metabolism Flashcards
What is the most common monogenic disorder of carbohydrate metabolism?
classical galactosemia
What enzyme is defective in classical galactosemia?
galactose-1-phosphate uridyl transferase
What are some clinical manifestations of classical galactosemia?
failure to thrive, hepatic insufficiency cataracts and developmental delay.
Scenario: patient presents with accumulations of urea precursors such as ammonium and glutamine. It’s also noted that this is an X-linked disorder. What enzyme is defective?
ornithine transcarbamylase (OTC deficiency)
Van Gierke’s disease is a defective storage disorder of what substance?
glycogen
What enzyme is defective in Van Gierke’s disease?
G6 phosphatase
Case scenario: baby presents with poor feeding, failure to thrive, hepatic and renal insufficiency and death. It is noted that the baby cannot metabolize fructose properly. What enzyme is defective?
fructose 1,6-bisphophate aldolase
What is characteristics about Mucopolysaccharidoses (MPS disorders)?
Caused by a reduced ability to degrade one or more glycosaminoglycans (GAGs)
What are some clinical features of Mucopolysaccharidoses (MPS disorders)?
chronic and progressive multisystem deterioration, which causes hearing, vision, joint and cardiovascular dysfunction
What enzyme is defective in Phenylketonuria (PKU)
Mutation of phenylalanine hydroxylase (PAH)
What is defective to cause Gaucher disease?
acid β-glucosidase
What are the clinical characteristics of Gaucher disease?
visceromegaly, multiorgan failure, and debilitating skeletal disease.
What is defective in I-cell disease?
recognition marker of mannose-6-phoshate causing partially degraded oligosaccharides, lipids and glycosaminoglycans
What are the clinical manifestations in I-cell diesase?
coarse facial features, skeletal abnormities, corneal opacities, mental retardation and early death
What is defective in cystinuria disease?
Caused by abnormal cystine transport between cells and the extracellular environment cause cystinuria