Stinging or burning of the skin may result within
1 hour of sun exposure. This is followed by edema and erythema. Solar
urticaria, petechiae, vesicles, purpura, and crustification may develop and
last for several days. Late skin changes include thickening of the skin with
a waxy appearance, shallow pits, and linear creases on the face
(particularly cheeks and nose). Artificial lights, particularly operating
room lamps, may cause photosensitivity. Cholelithiasis is fairly common (in
approximately 30% of patients) and may present at an unusually early age.
Hepatic cholestasis is rare (1-4% of patients) but often has a severe
course. Rarely, hemolytic or mild hypochromic anemia is present, and mild
(nonhemolytic) anemia has been described in up to 25% of cases.
Polyneuropathy and quadriparesis may occur. Excessive protoporphyrin is
excreted in bile, and hence in feces, but not in urine because
protoporphyrin is only poorly water-soluble. It may be deposited in the
liver, resulting in progressive and even fatal liver damage. Management
includes avoidance of exposure to sunlight (ensure that the chosen sunscreen
also protects in the 400-nm range, as common commercial sunscreens often
only effectively block light with a wavelength of approximately 300 nm)
and/or skin protection by parenteral administration of beta-carotene. Liver
disease may be ameliorated by treatment with cholestyramine (to prevent
enterohepatic recirculation of protoporphyrin), activated charcoal, and bile
salts.