Pellagra | |
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The skin features of pellagra including peeling, redness, scaling, and thickening of sun-exposed areas. | |
Specialty | Dermatology |
Symptoms | Inflammation of the skin, diarrhea, dementia, sores in the mouth[1] |
Types | Primary, secondary[1] |
Causes | Not enough niacin[2] |
Diagnostic method | Based on symptoms[3] |
Differential diagnosis | Kwashiorkor, pemphigus, photodermatitis, porphyria[3] |
Prevention | Consuming Niacin |
Treatment | Niacin or nicotinamide supplementation.[1] |
Prognosis | Good (with treatment), death in ~ 5 years (without treatment)[3] |
Frequency | Rare (developed world), relatively common (developing world)[3] |
Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B3).[2] Symptoms include inflamed skin, diarrhea, dementia, and sores in the mouth.[1] Areas of the skin exposed to friction and radiation are typically affected first.[1] Over time affected skin may become darker, stiffen, peel, or bleed.[1][3]
There are two main types of pellagra, primary and secondary.[1] Primary pellagra is due to a diet that does not contain enough niacin and tryptophan.[1] Secondary pellagra is due to a poor ability to use the niacin within the diet.[1] This can occur as a result of alcoholism, long-term diarrhea, carcinoid syndrome, Hartnup disease, and a number of medications such as isoniazid.[1] Diagnosis is typically based on symptoms and may be assisted by urine testing.[3]
Treatment is with either niacin or nicotinamide supplementation.[1] Improvements typically begin within a couple of days.[1] General improvements in diet are also frequently recommended.[3] Decreasing sun exposure via sunscreen and proper clothing is important while the skin heals.[1] Without treatment death may occur.[3] The disease occurs most commonly in the developing world, often as a disease of poverty associated with malnutrition, specifically sub-Saharan Africa.[3]