Lect 15 - Inborn errors of metabolism Flashcards
what are the general outcomes of inborn errors of metabolism?
Accumulation of a toxin
Energy deficiency
Deficient production of essential metabolite / structural component
what accumulates in patients with urea cycle defects?
Ammonia
what is Porphyrin?
a molecule that is required in the pathway to produce haem?
what is raised in acute porphyria
PBG
what is raised in Photosensitive
porphyria
PROTOPORPHRIN
where do fats get metabolised?
in mitochondria
what do fats get broken down into?
acetyl CoA and then ketones.
what is to androgen insensitivity syndrome caused by?
Defective receptors
what are the symptoms of androgen insensitivity syndrome?
healthy female phenotype: normal breast development absent pubic hair. possible ambiguous genitalia
YET GENETIC MALE
how does androgen insensitivity syndrome present?
primary amenorrhoea, infertility
what causes the variations in presentation of patients with inborn errors of metabolism
Variability of other aspects / components of metabolism
Environment
how are IEM diagnosed
Pre-symptomatic screening
Investigation of symptomatic individuals
what Investigations of symptomatic individuals can be done?
test body fluids for abnormal metabolites
measure enzyme activities
histochemical / immunochemical staining
DNA analysis
what does the Leeds basic urine metabolic screen test for?
Spot tests Organic acids Amino acids Sugar Chromatography Oligosaccharides/Sialic Acids Mucopolysaccharides
What GCSE level science experiment can be used to find excess of particular amino acids in a sample?
Amino acid TLC
(Chromatography)
This is done with a more sophisticated automated machine, but principle is the same.