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Flashcards in Porphyrias Deck (9)
1

What is meant by cutaneous photosensitivity?

Abnormal skin reaction to UV, and sometimes visible, light

2

What is porphyria?

Hereditary disease where there is build up of porphyrins, caused by reduced enzyme activity in the haem pathway
These react with light to produce skin reactions

3

Name the 3 most common porphyrias

Porphoryia cutanea tarda
Erythropoietic protoporphyria
Variegate porphyria

4

How does porphyria cutanea tarda arise?

Reduced activity of uroporphyrinogen decarboxylase causes build up of uroporphyrins that react with light

5

List symptoms of porphyria cutanea tarda

Blistering
Skin fragility
Hyperpigmentation
Hypertrichosis

6

List 4 causes of porphyria cutanea tarda

Alcohol
Viral hepatitis
High oestrogen
Haemachromatosis

7

How does erythropoietic protoporphyria arise?

Reduced activity of ferrochelatase causes build up of protoporphyrins

8

List symptoms of erythropoietic protoporphyria

Swelling/burning
Itching
Pain

9

How does acute intermittent porphyria arise?

Reduced activity of PBG deaminase causes build up of uroporphyrins