If untreated,<unk>  can kill within four or five years. Treatment is with nicotinamide, which has the same vitamin function as niacin and a similar chemical structure, but has lower toxicity. The frequency and amount of nicotinamide administered depends on the degree to which the condition has progressed.
Pellagra
Pemphigus
Koilonychia
Kwashiorkor
Melanonychia
Porphyria
Crepitus
Photodermatitis