EPP

Introduction

Erythropoietic protoporphyria is a disease of porphyrin metabolism characterized by abnormally elevated levels of protoporphyrin IX in erythocytes (mature blood cells), feces and plasma (the fluid portion of circulating blood), and by sensitivity to visible light.

This sensitivity manifests itself as a burning sensation in the skin, followed by varying degrees of erythema (redness of the skin due to capillary dialation) and edema (swelling caused by excess fluids). Consequently, patients with the disorder commonly avoid exposure of the skin to strong light. They tend to choose indoor occupations, nocturnal work, or to venture outdoors while heavily clothed to protect the skin.