ABSTRACT
Complement components have been detected at the vessel walls and dermoepidermal junction of skin of patients with porphyrias. The porphryias will be discussed here in the order of the defective enzymes as they appear in the heme biosynthetic pathway. It should be emphasized that in all patients suspected of having porphyrias, a complete porphyrin profile analysis, including quantitative porphyrin determinations in 24 hr urine, feces, plasma, and erythrocytes should be performed; all of these can be ordered through commercial laboratories. All patients with photosensitive porphyrias should be advised to avoid sunlight; physical sunblocks offer the only complete protection: chemical sunscreens do not completely protect against the action spectrum of porphyrins. Sun protection is essential. A quencher of singlet oxygen, beta-carotene, at oral dosages ranging from 30–90 mg/day in children and 60–180 mg/day in adults is commonly used. Management of hepatic failure is exceedingly difficult; therapeutic modalities that have been tried include cholestyramine, iron, and liver transplantation.
