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Diarrhea,Eczema and Dementia and other Skin Signs of Vitamin-B3 Deficiency Disease Pellagra
Pellagra is common in populations with maize as a staple diet
Role of Vitamin-B3 in Proper Functioning of Our Body and Causes of its Deficiency
Niacin or Vitamin-B3 is obtained from the diet or may be synthesized from protein component Tryptophan in our body.
An average of about 1 mg of niacin is formed from 60 mg of dietary Tryptophan. Many food stuffs, especially cereals contain bound forms of niacin which is not nutritionally available.
It is an essential component of carbohydrate and fat metabolism in our body.
Historically the most important reason for its deficiency has been inadequate dietary intake, chiefly in poor populations surviving on corn-based diets. Corn does contain sufficient quantities of vitamin-B3 to meet our dietary requirements, but much of this exists in the bound form that cannot be digested and absorbed easily.
A traditional practice among the natives of Mexico and Central America to soak corn in alkali prior to cooking was protective against vitamin B3 deficiency. It served to hydrolyze the bound niacin and inactivate the toxins that accumulated in stored grain contaminated with moulds.
The introduction of degermination during the milling of corn inhibited the liberation of bound niacin, reducing its content by 25-40% in corn products and predisposed to the development of pellagra when maize was a major element of the diet.
Others at risk of niacin deficiency include alcoholics, elderly persons, homeless people and the mentally ill.
Intestinal malabsorption due to swelling of intestines (jejuno ileitis), Crohn's disease and gastrectomy operations may also lead to pellagra.
Medicines like isoniazid, commonly used to treat tuberculosis impair vitamin-B3 production in our body, and anti cancer medicines 6-Mercaptopurine and 5-Flourouracil interfere with its formation, leading to its deficiency. Individuals taking sulphonamide antibiotics, anticonvulsant medication and antidepressants are also at risk of vitamin-B3 deficiency.
Kava, an intoxicating beverage made from the root of Piper methysticum in the South Pacific region, may produce pellagra like symptoms.
Carcinoid tumors (a malignancy of argentaffin cells secreting serotonin, histamine and prostaglandins and causing facial flushing and abdominal cramps) produce large quantities of chemical serotonin, depleting Tryptophan, which is a substrate for vitamin-B3 synthesis.
Hartnup's disease, a heriditary disorder is associated with poor absorption of amino acid Tryptophan from the diet leading to vitamin-B3 deficiency.
In the modern world this problem is rarely encountered, other than in chronic alcoholics, people with digestive disorders or severe psychiatric disturbances who live on an unbalanced diet.
Diarrhea - a Common Symptom of Pellagra
Early symptoms of vitamin B3 deficiency include loss of appetite, weakness, irritability, mouth soreness and weight loss.
Diarrhea when present, is associated with stomach ache and results from swelling of the inner lining of intestines, along with achlorhydria or absence of hydrochloric acid secretion from the stomach, glossitis or swelling of the tongue and stomatitis or swelling of the mouth.
When severe, diarrhea can lead to malabsorption due to flattening of the intestinal villi, the finger like projections in the inner lining of intestines that greatly increase its surface area and aid in better absorption of food.
Skin signs of Pellagra
Skin Manifestations of Pellagra
Vitamin-B3 deficiency makes an individual's skin photosensitive.
The skin changes are bilateral, symmetrical and present on sites exposed to sunlight, heat, friction and subject to localized pressure.
It starts as redness and itching with associated burning on front of hands and is associated with slight amount of swelling on hands.
As the disease progresses, redness evolves into blisters that enlarge and then burst open, forming scabs or drying up into dark brown scales or crusts. On the face, these scabs are thicker, larger and associated with pus filled blisters.
In the next stage, the crusts become hard, rough, cracked, blackish and brittle. The skin of fingers thickens and skin markings disappear. Later on, painful deep fissures develop on palms and fingers.
In advanced stages of the disease, the skin of entire torso is affected and covered with scales and brown colored crusts.
Typical Skin Signs of Pellagra
This deficiency disease is associated with sensitivity towards sunlight, so lesions develop mostly on sun exposed surfaces that include the face and neck, front of hands, arms and feet. The typical skin signs suggestive of Pellagra include the following :
- Glove of Pellagra - On the front of hands, the eczema patches extend up on the arms to form a "glove" of pellagra. The patches are symmetrical and clearly demarcated from the normal skin.
- Boot of Pellagra - Eczema develops on the front and back of legs to form a "boot".
- Butterfly eruption on the face - The changes resemble that of a sunburn. On the face, eczema covers the "butterfly area", which includes symmetric distribution on the cheeks, chin, lips, sides of nose and forehead. The appearance is similar to that of lupus erythematosus, but the intensity of disease is less severe. On the forehead, there is a narrow border of normal skin between the eczema and scalp. The skin changes on face are accompanied by lesions on arms and other parts of the body.
- Casal's Necklace - A broad band or collar of eczema develops around the neck in the shape of a necklace or a "cravat". This corresponds to the part of neck most exposed to sunlight.
Healing of skin lesions after starting the treatment occurs in a centrifugal pattern, with the periphery showing active disease, even after the central part of the patches have healed.
Signs and Symptoms of Vitamin-B3 Deficiency
Changes in the digestive tract
Symmetric patches on sun exposed areas
Depression and apathy
Redness on butterfly area of the face
Inability to sleep
Brownish black crusts due to hemorrhages
Disorientation and dementia
Mental Changes Associated with Vitamin-B3 Deficiency
During the initial stages of deficiency, non-specific symptoms like fatigue, inability to sleep, apathy and depression are present. The affected person may become indifferent, avoid social interactions and would not seem to be affected by anything happening around or express concern, excitement, grief or happiness.
As the deficiency progresses, encephalopathy (swelling of brain) and depression of brain functions begins to develop, that leads to confusion, disorientation, restlessness, hallucinations, loss of memory and eventually frank madness or psychosis.
Abnormal sensations and tingling may also accompany altered mentation, and are due to coexisting deficiencies of other vitamins.
Dietary Sources of Niacin
Dietary Sources of Vitamin-B3 and Treatment of Pellagra
In very advanced stages of the disease, the vitamin has to be injected directly into the vein in doses of 50-100 mg once or twice a day.
More commonly, Niacinamide is administered by mouth as 100-300 mg tablets in divided doses.
It can also be given subcutaneously in uncooperative individuals or when severe diarrhea is present.
Multivitamins (including other B-complex vitamins) and a high quality protein diet are essential supportives to treat pellagra.
With proper treatment, the condition of an affected person begins to improve within a day or two.
Recommended Daily Allowance of Vitamin-B3 : 18 mg/day for a mature human adult.
Food sources rich in niacin and/or tryptophan include the following :
- Legumes (peas, beans, lentils)
- Groundnut and other nuts
- Some green veggies
- Tea and coffee.
Milk is a poor source of vitamin-B3, but its proteins are rich in tryptophan which is converted in the body into niacin.
Brewer's yeast is a rich source of Vitamin-B3, which is also present in high concentration in the germ and pericarp or bran of cereal grains.