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(pĕ-lag′ră) [L. pellis, skin + Gr. agra, seizure] The clinical consequences of profound niacin deficiency characterized by cutaneous, gastrointestinal, mucosal, and neurological symptoms.

 INCIDENCE: It is found in regions of the world where malnutrition is endemic.

 CAUSES: This condition is due to inadequate intake or absorption of niacin (nicotinic acid) or its amide (niacinamide, nicotinamide). It is commonly associated with restricted or limited diets in which a single cereal grain, esp. corn, is consumed without adequate consumption of wheat, eggs, beef, poultry, or other foods rich in niacin or tryptophan. The condition is often found in chronic alcoholism.

 SYMPTOMS AND SIGNS: In advanced cases, stomatitis and glossitis, diarrhea, dermatitis, and central nervous system involvement occur. Cutaneous lesions include erythema followed by vesiculation, crusting, and desquamation. The skin may become dry, scaly, and atrophic. The mucous membranes of the mouth, esophagus, and vagina may atrophy; ulcers and cysts may develop. Anemia is common. Nausea, vomiting, and diarrhea occur, the last being characteristic. Involvement of the central nervous system is first manifested by neurasthenia, followed by organic psychosis characterized by disorientation, memory impairment, and confusion. Later, delirium and clouding of consciousness may occur.

 DIAGNOSIS: Pellagra is diagnosed by the presence of its classic signs and symptoms: “dermatitis, diarrhea, and dementia” (the three D’s). There are no definitive laboratory tests for pellagra, but reduced levels of methylnicotinamide and pyridone (two metabolites of niacin) support the clinical diagnosis.

 TREATMENT: The disease is treated by following a diet adequate in all vitamins, minerals, and amino acids supplemented by 500 to 1000 mg of niacinamide given orally three times daily. If there is any doubt about the ability of the intestinal tract to absorb vitamins, the vitamins should be given parenterally.

PATIENT CARE: Maintaining an adequately diversified and fortified diet is the key to personal and population-based elimination of pellagra. In the southern U.S., where pellagra was endemic until the early 20th century, enrichment of flours used in making bread with iron, niacin (nicotinic acid) and thiamine helped eradicate pellagra and other childhood nutritional deficiencies.

 Skin lesions caused by pellagra should be treated with topical emollients. Mouth rinses and washes with soothing ingredients including antihistamines and antacids containing magnesium can be used for the patient’s comfort.


(pĕl′ĕt) [Fr. pelote, a ball] 1. A tiny pill or small ball of medicine or food. 2. A solid that condenses at the bottom of a centrifuged solution. 3. Any small round object, such as a bit of buckshot or a BB, that may enter the body in gunshot injuries.

cotton p. A small rolled cottonball, less than ⅜ in (about 1 cm) in diameter, used for desiccation or topical application of ...

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