Pellagra is clinically manifested by the 4 D' s: photosensitive dermatitis, diarrhea, dementia, and death. The full tetrad of symptoms is usually not well developed in infants and children. This vitamin deficiency responds to treatment with nicotinic acid.  See the image below.
Pellagra is observed in malnourished individuals and as a complication of isoniazid therapy; however, the diagnosis is often overlooked or delayed, occasionally with life-threatening consequences. Isoniazid-induced pellagra may occur despite pyridoxine supplementation.
Pellagra first was recognized in the United States in 1902, and it became an epidemic in the American South.  Poverty and corn consumption were the most frequently observed risk factors. The public became pellagraphobic, and patients were shunned and ostracized. Hungarian born Dr Joseph Goldberger of the United States Public Health Service eventually solved the problem. He was able to prevent and induce pellagra by using dietary modification. 
Pellagra is defined by the systemic disease resulting from niacin deficiency, and it is characterized by diarrhea, dermatitis, dementia, and death, which usually appear in this order. GI tract symptoms always precede dermatitis, or, according to Rille, "Pellagra begins in the stomach". 
Gasper Casal first described pellagra in 1762 in Oviedo, Asturias. Casal noted the malady among poor peasants of Asturias and termed it mal de la rose because all affected patients had the typical reddish and glossy rash on the dorsum of the hands and feet. Skin lesions on the neck are designated as the Casal necklace. Casal had observed that patients with pellagra were all poor, subsisted mainly on maize, and rarely ate fresh meat. Before Casal, the skin changes were termed Hiob disease; stigmata of Saint Francis of Assisi; or, in Italy, scorbuto alpino. François Thiery published the first description of pellagra in 1755. Francesco Frapolli called the disease vulgo pelagrain and first used the term pellagra in 1771.
In Italian vernacular, pellagra means "skin that is rough" and refers to the thickened, rough skin of persons with pellagra. In Italian, pelle means skin, and agra means sour. Pellagra remained endemic among maize-eating peasants of southern Europe for almost 2 centuries before it was recognized in the United States. In 1914, scientists suggested that pellagra was caused by a deficiency of some nutrient in the diet and that the disorder appeared to be related to black tongue (a condition analogous to pellagra) in dogs. In 1937, Conrad Elvehjem discovered that nicotinic acid cured black tongue. 
In the United States, pellagra was first reported in 1902. In Europe, the highest incidence was in the Mediterranean area. The first cases were reported in France in 1818, in Egypt in 1847, in England in 1866, and in Bulgaria in 1907. Over the following 2 decades, pellagra occurred in epidemic proportions in the American South. Poverty and the consumption of corn were the most frequently observed risk factors. The medical community implicated the consumption of spoiled maize as the cause of pellagra, which occurred among those who were less affluent; this suggestion caused economic repercussions for agriculturists.
Goldberger eventually solved the secret of the malady, which was a faulty diet. Goldberger was able to prevent and induce pellagra with dietary modifications, a landmark event in the annals of medicine, nutrition, and epidemiology. The reference range for serum nicotinic acid levels is 740-790 g; this level is decreased in patients with pellagra.
HIV infection induces a pellagralike state; plasma tryptophan levels are decreased in patients with HIV infection. High-dose nicotinamide treatment may successfully reverse this HIV-induced metabolic abnormality. Niacin is proposed to be a secondary preventive factor of AIDS in patients with HIV infection. [5, 6, 7]
Pellagra is the late stage of severe niacin deficiency. Niacin, or vitamin B-3, is a water-soluble vitamin. In 1926, Goldberger reported that nicotinamide was a preventive factor of pellagra.
Pellagra can be divided into primary and secondary forms. Primary pellagra results from inadequate nicotinic acid (ie, niacin) and/or tryptophan in the diet (long-term parenteral nutrition without appropriate niacin substitution; anorexia nervosa; a self-imposed restriction diet in adult atopics with sensitizations to multiple foodstuffs). Niacin is a pyridine carboxylic acid that is converted into an amide in the body.
Niacin is required for adequate cellular function and metabolism as an essential component in coenzyme I (oxidized form of nicotinamide adenine dinucleotide [NAD]) and coenzyme II (reduced form of nicotinamide adenine dinucleotide phosphate [NADP]), which either donate or accept hydrogen ions in vital oxidation-reduction reactions. These compounds are important coenzymes for glycolysis, protein and amino acid metabolism, pyruvate metabolism, pentose biosynthesis, high-energy phosphate bond generation, glycerol metabolism, and fatty acid metabolism.
Nicotinamide has an in vitro down-regulatory effect on proinflammatory cytokines interleukin (IL)–1beta, IL-6, IL-8, IL-12, and tumor necrosis factor-alpha in a dose-dependent manner. Furthermore, it induces activation of tumor necrosis factor cachectin–induced macrophages and inhibits the expression of intercellular adhesion molecule 1 and major histocompatibility complex II. . Nicotinamide is a potent phosphodiesterase inhibitor and suppresses neutrophil chemotaxis, mast cell histamine release, and antigen-induced lymphocyte transformation. It is able to scavenge oxygen radicals and to inhibit nitric oxide synthase mRNA induction in activated macrophages. Nicotinamide increases biosynthesis of ceramides, which, upon degradation, produce sphingosine. This inhibits protein kinase C and decreases basal cell proliferation.
This immunomodulatory and anti-inflammatory effect of nicotinamide in vitro may have great potential for the treatment of human inflammatory diseases by inhibition of neutrophil chemotaxis and secretion of inflammatory cytokines, suppression of lymphocyte transformation, and inhibition of mast cell histamine release and blockade of histamine receptors. Beneficial effects of topically applied nicotinamide in aging skin, such as improvement in barrier functions in atopic dry skin and decreased appearance of signs of facial photoaging (eg, skin texture changes and hyperpigmentation), have been noted. Nicotinic acid can be formed from dietary tryptophan. Maize contains appreciable amounts of niacin, but this niacin is present in a bound form. Treating corn used for dietary staples (eg, tortillas) with lime results in the release of bound niacin.
Because cellular functions in multiple organs and tissues are affected by niacin deficiency, the clinical expressions of pellagra are diverse. Pathologic changes in the skin include vascular dilatation, proliferation of the endothelial lining, perivascular lymphocytic infiltration, hyperkeratinization, and subsequent atrophy of the epidermis. Mucosal inflammation and atrophy involve most of the GI tract. Evidence of glossitis and atrophy of the papillae of the tongue are characteristic findings, along with gastritis and subsequent gastric mucosal atrophy. Acute inflammation of the small intestine and colon are also commonly noted. Pathologic changes in the nervous system can be found in the brain, spinal cord, and peripheral nerves. Findings include patchy demyelinization and degeneration of the affected parts of the nervous system.
Secondary pellagra occurs when adequate quantities of niacin are present in the diet, but other diseases or conditions interfere with niacin absorption and/or processing. Examples of these conditions include prolonged diarrhea; chronic alcoholism; chronic dialysis treatment; chronic colitis, particularly ulcerative colitis or regional enteritis; cirrhosis of the liver; tuberculosis of the GI tract; malignant carcinoid tumor; and Hartnup syndrome. Alcoholism can be considered a risk factor for pellagra, which can, as well, be considered an alcoholism indicator.  Clinical manifestations of pellagra are a less sensitive indicator than biochemical niacin deficiency in carcinoid patients with carcinoid syndrome. Occasionally, an abortive form called pellagroid (eg, erythema pellagroids, pseudopellagra) is present. Hartnup syndrome is an inborn error of tryptophan metabolism.
In addition, the use of isoniazid is known to cause the symptoms of pellagra, as does the long-term administration of 5-fluorouracil. Isoniazid biochemically competes with niacin. Pellagra was also noted as a cutaneous adverse reaction after consumption of Kombucha tea.
Pellagra can develop in atopic dermatitis patients following elimination diets.  It is important to consider that there is some crossover of the clinical and histological features with pellagra and necrolytic migratory erythema.
The current incidence of pellagra in the United States is unknown. Epidemics of pellagra no longer occur. Sporadic cases of pellagra can be seen among patients with long-term alcoholism, food faddists, individuals dependent on illegal drugs, and patients with malabsorption states. [10, 11, 12]
Although the exact incidence of pellagra in other countries is not known, pellagra occurs mainly in developing nations in which corn and corn products are the major food sources, if the corn is not specially treated. Pellagra also occurs in ethnic populations whose diets are deficient in niacin and/or tryptophan. [13, 14]
No racial predilection is reported.
No sex predilection is described. The only risk factor for pellagra is dietary deprivation of niacin.
Pellagra is typically a disease that occurs in adults. Pellagra may develop in adolescents and young children if they are exposed to a pellagragenic diet. Pellagra rarely occurs in infants. Historically, dermatitis associated with kwashiorkor was mistaken for infantile pellagra. 
If pellagra is diagnosed and treated appropriately, the prognosis for recovery is excellent. Untreated pellagra results in death from multiorgan failure. The morbidity of pellagra is related to its effects on the organ systems involved.
Dermatitis tends to be pruritic, often with a painful burning sensation during the acute phase, although patients may be asymptomatic. The skin eventually becomes hypopigmented, and some patients consider this disfiguring.
Systemic effects of the disease include malaise, apathy, weakness, and lassitude. GI tract involvement leads to a malabsorptive state and a subsequent failure to thrive.
Neurologic manifestations include anxiety, depression, delusions, hallucinations, and stupor.
What would you like to print?