[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Conditions](https://durgical.com/en/conditions/) › Erythropoietic protoporphyria

[Conditions](https://durgical.com/en/conditions/) · [Metabolism: heme, bilirubin and iron](https://durgical.com/en/conditions/)

# Erythropoietic protoporphyria

An inherited porphyria that causes burning skin pain within minutes of sun exposure, starting in childhood.

Updated 2026-11-01

## Structures involved

Tap one to see what it is and open it in 3D.

- [Skin](https://durgical.com/en/anatomy/skin/)
- [Liver](https://durgical.com/en/anatomy/liver/)
- [Gallbladder](https://durgical.com/en/anatomy/gallbladder/)

## In biochemistry

- [Heme synthesis: Step 1 · ALA synthase (ALAS1 liver, ALAS2 erythroid)](https://durgical.com/en/biochemistry/pathways/heme-synthesis/#paso-1)
- [Heme synthesis: Step 8 · Ferrochelatase](https://durgical.com/en/biochemistry/pathways/heme-synthesis/#paso-8)
- [ALA synthase](https://durgical.com/en/biochemistry/enzymes/ala-synthase/)
- [Ferrochelatase](https://durgical.com/en/biochemistry/enzymes/ferrochelatase/)
- [Protoporphyrin IX](https://durgical.com/en/biochemistry/molecules/protoporphyrin-ix/)

## What it is

A cutaneous porphyria due to low ferrochelatase activity (or, in the X-linked form, excess ALAS2) that piles up free protoporphyrin in red cells, skin and liver.

## Who gets it

It is the most common porphyria in children; symptoms begin in early childhood. It often goes undiagnosed for years because the skin looks almost normal.

## Causes

- One non-functional FECH allele plus a common low-expression variant on the other
- X-linked protoporphyria: gain-of-function ALAS2 mutations

## Risk factors

- Family history
- Strong sun exposure (also through window glass)

## Pathophysiology

Iron-free protoporphyrin IX builds up in red cells and passes into the skin. When it absorbs visible light it generates reactive oxygen that damages dermal vessels: pain and swelling without blisters. It is hydrophobic and leaves through bile, where it can form stones and damage the liver.

## Symptoms and signs

- Burning, stinging and itching of exposed skin minutes after sunlight
- Redness and swelling of the hands and face
- Thickened skin on the knuckles and fine scars on the nose
- Mild microcytic anemia

## Red flags

- Jaundice, dark urine or abdominal pain (protoporphyrin liver damage)
- Burns under operating-room lights

## Diagnosis

**Clinical**
Immediate pain with sunlight since childhood, with few or no visible [skin](https://durgical.com/en/anatomy/skin/) findings.

**Tests**
Markedly raised red-cell protoporphyrin, mostly free (metal-free); normal urine porphyrins; [liver](https://durgical.com/en/anatomy/liver/) tests and ferritin; FECH and ALAS2 testing.

**Imaging**
Abdominal ultrasound to look for gallstones and signs of liver disease.

## Treatment

**Lifestyle**
Protection from visible light: covering clothing, window films and zinc oxide or titanium dioxide sunscreens

**Medical**
Afamelanotide, a melanocyte-stimulating hormone analogue that raises sun tolerance

**Follow-up**
Regular monitoring of liver tests, iron and vitamin D

**Surgical**
Liver transplantation for protoporphyrin liver failure, followed by bone marrow transplantation to prevent recurrence

## Complications

- Gallstones
- Cholestatic liver disease and liver failure (a few cases)
- Vitamin D deficiency

## Test yourself

Think of the answer, then tap the question to see it.

## Which enzyme fails in erythropoietic protoporphyria?

Ferrochelatase, the last step of heme synthesis.

## Why are urine porphyrins normal in protoporphyria?

Protoporphyrin is hydrophobic and is excreted in bile, not urine.

## How does the protoporphyria skin reaction differ from porphyria cutanea tarda?

Protoporphyria causes immediate pain without blisters; porphyria cutanea tarda causes blisters and fragility without immediate pain.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/conditions/erythropoietic-protoporphyria/)

## Related conditions

- [Porphyria cutanea tarda](https://durgical.com/en/conditions/porphyria-cutanea-tarda/)
- [Gallstones (cholelithiasis)](https://durgical.com/en/conditions/gallstones/)

Educational information, not medical advice. For any symptom, see a health professional.

Sources: [Porphyria: MedlinePlus Genetics](https://medlineplus.gov/genetics/condition/porphyria/) (MedlinePlus, US National Library of Medicine, 2026); [FECH gene: MedlinePlus Genetics](https://medlineplus.gov/genetics/gene/fech/) (MedlinePlus, US National Library of Medicine, 2026); [Porphyrins blood test: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/003372.htm) (MedlinePlus, US National Library of Medicine, 2026); [ALAS2 gene: MedlinePlus Genetics](https://medlineplus.gov/genetics/gene/alas2/) (MedlinePlus, US National Library of Medicine, 2026).

[← All conditions](https://durgical.com/en/conditions/)

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/conditions/erythropoietic-protoporphyria/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/conditions/erythropoietic-protoporphyria/