Erythropoietic protoporphyria
Mario Lecha1, Hervé Puy, Jean-Charles Deybach
1Department of Dermatology, Hospital Clinic, University of Barcelona, Barcelona, Spain. 4908mlc@comb.es
Orphanet Journal of Rare Diseases
|September 12, 2009
Summary
Erythropoietic protoporphyria (EPP) is an inherited disorder causing painful photosensitivity and potential liver failure due to protoporphyrin accumulation. Management focuses on light avoidance and monitoring liver health to prevent severe complications.
Area of Science:
- Biochemistry
- Genetics
- Dermatology
Background:
- Erythropoietic protoporphyria (EPP) is an inherited metabolic disorder characterized by protoporphyrin accumulation.
- This leads to photosensitivity, liver disease, and gallstones.
- EPP affects approximately 1 in 75,000 to 200,000 individuals worldwide.
Purpose of the Study:
- To describe the clinical manifestations, pathophysiology, diagnosis, and management of EPP.
- To highlight the genetic basis of EPP, including mutations in FECH and ALAS2 genes.
- To emphasize the importance of monitoring and managing liver complications.
Main Methods:
- Diagnosis involves measuring elevated protoporphyrin levels in plasma and erythrocytes.
- Genetic analysis identifies mutations in the FECH and ALAS2 genes.
- Clinical evaluation includes assessing photosensitivity, liver function, and family history.
Main Results:
- EPP typically manifests in infancy with painful skin reactions to sunlight.
- Patients are at risk for cholelithiasis and progressive liver disease, potentially leading to acute liver failure.
- Most cases result from ferrochelatase deficiency (FECH gene), with a smaller percentage caused by ALAS2 mutations.
Conclusions:
- EPP is a lifelong condition requiring careful management of photosensitivity and liver disease.
- Regular hepatic monitoring is crucial for early detection and prevention of liver failure.
- Liver and bone marrow transplantation may be necessary for severe cases.
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