Gastroenterostomy can also cause pellagra. Chronic alcoholism can also cause poor absorption which combines with a diet already low in niacin and tryptophan to produce pellagra. Hartnup disease is a genetic disorder that reduces tryptophan absorption, leading to pellagra. Alterations in protein metabolism may also produce pellagra-like symptoms. An example is carcinoid syndrome, a disease in which neuroendocrine tumors along the GI tract use tryptophan as the source for serotonin production, which limits the available tryptophan for niacin synthesis. In normal patients, only one percent of dietary tryptophan is converted to serotonin; however, in patients with carcinoid syndrome, this value may increase to 70%. Carcinoid syndrome thus may produce niacin deficiency and clinical manifestations of pellagra. Anti-tuberculosis medication tends to bind to vitamin B6 and reduce niacin synthesis, since B6 (pyridoxine) is a required cofactor in the tryptophan-to-niacin reaction. Several therapeutic drugs can provoke pellagra. These include the antibiotics isoniazid, which decreases available B6 by binding to it and making it inactive, so it cannot be used in niacin synthesis, and chloramphenicol; the anti-cancer agent fluorouracil; and the immunosuppressant mercaptopurine. Treatment
If untreated, pellagra 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. Epidemiology
Pellagra can be common in people who obtain most of their food energy from corn, notably rural South America, where maize is a staple food.
Red streaks in the skin along the direction of regional lymph nodes indicate lymphatic involvement. Infection may spread within hours and can cause sepsis and death. Symptoms and signs
Warm skin over site of infection. The person may also have chills and a high fever - between 38 and 40 degrees Celsius - along with moderate throbbing pain and swelling. The red streaks can be clearly outlined and demarcated or just barely visible, particularly in dark-skinned patients. Malaise, tenderness at the site of infection, skin ulcers (a rare symptom of lymphangitis), rapid pulse, and enlarged, swollen, and tender lymph nodes are also seen. Appetite loss has been documented with the presence of inflammation (inflammation-associated anorexia), but it is unclear whether appetite loss seen in patients with lymphangitis leads to weight loss; in cases that develop after lymphedema—which can be upwards of 8.14% of the time—weight gain has actually been documented.If these symptoms are absent, it is suggestive of other underlying disorders such as tuberculosis, lymphoma, or Hodgkin’s disease. A person with lymphangitis should be hospitalized and closely monitored by medical professionals. In very minor cases, regular application of antibiotic creams and cleanliness of the area can accelerate the healing process with no medical professional intervention or consultation required. When the inferior limbs are affected, the redness of the skin runs over the great saphenous vein location and can be confused for thrombophlebitis. Chronic lymphangitis is a cutaneous condition that is the result of recurrent bouts of acute bacterial lymphangitis.