Erythropoietic Protoporphyria
Also known as: EPP, Protoporphyria, Erythrohepatic Protoporphyria
Erythropoietic protoporphyria (EPP) is a rare genetic metabolic disorder characterized by abnormal accumulation of protoporphyrin in erythrocytes (red blood cells), plasma, and sometimes the liver. This buildup leads to acute photosensitivity, causing painful, non-blistering skin reactions upon exposure to sunlight or certain artificial lights. In some cases, EPP can result in liver complications, including protoporphyric hepatopathy and liver failure.
Imagine your skin is super sensitive to sunlight. That's like having EPP. When you go in the sun, your skin gets really painful, red, and itchy, but it doesn't usually get blisters. It's because your body has too much of a certain substance called protoporphyrin. You need to be extra careful in the sun and wear protective clothing.
Signs & Symptoms
- Acute photosensitivity (pain, burning, itching upon sun exposure)
- Erythema (redness) and edema (swelling) of the skin
- Burning sensation without blistering
- Chronic skin thickening and scarring (lichenification)
- Gallstones (protoporphyrin stones)
- Liver dysfunction (in some cases)
- Anemia (rare)
Treatment Options
Afamelanotide
HIGHLY EFFECTIVE Approved 2019Beta-Carotene
MODERATELY EFFECTIVECholestyramine
MODERATELY EFFECTIVEHematopoietic Stem Cell Transplantation (HSCT)
EXPERIMENTALLiver Transplantation
HIGHLY EFFECTIVESun Protection (protective clothing, sunscreens)
HIGHLY EFFECTIVEDiagnosis
- Clinical evaluation of symptoms
- Measurement of protoporphyrin levels in red blood cells, plasma, and feces
- Genetic testing for FECH and ALAS2 mutations
- Liver function tests
- Liver biopsy (in cases of suspected liver involvement)
History
Erythropoietic protoporphyria was first described in the 1960s. The genetic basis of EPP, involving mutations in the FECH gene, was identified in the 1990s. The development of afamelanotide has significantly improved the quality of life for many individuals with EPP.
Recent Breakthroughs
FDA Approves Afamelanotide for EPP
The FDA approved afamelanotide (Scenesse) for the treatment of erythropoietic protoporphyria. Afamelanotide is a synthetic melanocortin-1 receptor agonist that increases melanin production, providing photoprotection.