Prophyrias Flashcards
What is porphyria?
Rare inborn error of the enzymes invlved in the biosynthesis of haem resulting in overproduction of porphyrins
How is AI prophyria passed on?
Autosomal dominant
Presentation of AI porphyria
~30 y/o Women > men Severe poorly localised abdo pain neurologic symptoms Guillian-Barre syndrome Psychoses
What is the most common type of porphyria?
Porphyria cutanea tarda
How to investigate PCT?
Wood lamp
Presentation of PCT
Blisters/fragility Hyperpigmentation Hypertrichosis Solar urticaria Morphoea
Underlying causes of PCT
Alcohol
Viral hepatitis
Oestrogens
Haemachromatosis
What is erthyropeitin?
A hormone produced by the kidneys that increases the production of red blood cells in response to falling oxygen levels
Investigations for erthyropoeitic prophyria
Quantative RBC porphyrins Fluorocytes Transaminases Hb Biliary tract USS
Management of erthyropoetic porphyrias
Visible photoprotection measures
Anti-oxidants
avoid iron
Which enzyme is deficient in erythropoeitic porphyria?
Ferrochelatase
What does Erythropoietic protoporphyria cause a build up of?
Protoporphyrin IX
Presentation of erythropoietic protoporphyria
Presents in early childhood
Discomfort, itch or tingling in sun exposed skin
No clinical signs
Presentation of PCT
Middle aged
Blistering, scarring and milia formation of dorsal hands/forearms
Hypertrochosis
Which enzyme is deficient in PCT?
Uroporphyrinogen decarboxylase
