Porphyrias Flashcards
What are the main groups of porphyrias?
Phototoxic skin
Blistering and fragility skin
Acute attack
Severe congenital
Erythropoietic protoporphyria falls into which group?
Phototoxic skin
What are the commoner skin porphyria features?
Blistering
Fragility
Acute phototoxicity
What is the commonest skin porphyria?
Porphyria cutanea tarda
Porphyria cutanea tarda is caused by a deficiency in which enzyme?
Uroporphyrinogen decarboxylase
What are some of the typical presentations of PCT?
Blistering Fragility Hyperpigmentation Hypertrichosis Solar urticaria
How is a PCT investigated?
Woods lamp
What are some underlying causes of a PCT?
Alcohol
Viral hepatitis
Oestrogens
Haemochromatosis
What are the aims of managing a PCT?
Relieving the skin disease
Treating the underlying disease
An erythropoietic protoporphyria is causes by a deficiency in what enzyme?
Ferrochelatase
Who tends to be affected by erythropoietic protoporphyrias?
Children
What is the main symptom of erythropoietic protoporphyrias?
Phototoxicity
How are EPPs investigated?
By measuring quantitative RBC porphyrins
How is EPP managed?
Genetic counselling
6 month LFTs and RBC porphyrins
Visible light photoprotection measures
How can an acute intermittent porphyria present?
Acute abdomen
Guillain-Barre syndrome
Psychoses
