Pellagra has been called the disease of the 4 D’s-dermatitis (skin disease), diarrhea, dementia (failure to maintain normal mental state) and death. It is usually slow in its onset. It is characterized by tiredness, listlessness, headache, loss of weight and appetite, general poor health, sleepiness (somnolence) and muscle pains.
The distribution of skin lesions in pellagra is one of the first signs. They are usually found on part of the body exposed to sunlight or mechanical trauma. Lesions due to exposure to sunlight are found around the neck (Casal’s collar or necklace), on the back of hands, forearms, and on the other uncovered parts of the body. Elbows and knees are common pressure points exposed to mechanical trauma.
In the beginning these lesions appear to be like sun-bums-red, swollen and tender, itching and burning. If this condition is not treated, the skin becomes rough, scaly and ulcerated. There is diffused hyperigmentation resulting in darkening of complexion.
Digestive upsets are usual though not always present. Gastrointestinal symptoms are first limited to burning sensation of the epigastrium, gaseous distention and nausea. The tract is aggravated by the presence of intestinal parasites. The mucous membranes of the mouth are usually involved, displaying a scarlet glossitis with a swollen tongue (raw beef appearance) and increased salivation; eating and swallowing are painful.
In acute stages the underside of the tongue is ulcerated. Gastric and pancreatic secretions are diminished. This may be one of the underlying causes for the poor digestion and diarrhea in pellagra. There are profuse watery stools accompanied by blood and mucus. The rectum and anus also get affected. Due to diarrhea there is a deficiency of hydrochloric acid, poor digestion and resultant anaemia.
The central nervous system is affected. In mild cases the symptoms are weakness, tremors, anxiety, depression, irritability, confusion, fear, dizziness and poor memory. In acute cases there is lead pipe rigidity of the extremities, psychoneurosis leading to stupor and mania, delirium and paranoia.
Decreased sensation to touch loss of vibration and position sense may give rise to ataxia (loss of ability of muscular coordination). Finally paralysis occurs causing death.
Treatment and Prevention
The patient should be confined to bed until convalescence is well under way. Any specific vitamin deficiency requires therapy with the vitamins that are lacking. Usually synthetic vitamins are used to correct the deficiency in large doses.
For treatment a well balanced diet is given which contains 100 to 150 gms of high quality protein preferably from meat, milk, eggs, fish, liver, and poultry. Initially a full liquid diet devoid of roughage, avoids irritation of the intestinal mucosa. As the patient improves a general diet high in good protein is given. The diet should also contain good and moderate sources of niacin, such as wheat, millet, rice, fish, beef, mutton, pork, liver, kidney, yeast, groundnuts, meat extracts, pulses, cocoa powder, coffee, dried fruits and cashew nuts. It is also necessary to include other vitamins of B complex group for proper utilization of niacin. Although poor in nicotinic acid, milk is also effective in preventing pellagra because it is rich in tryptophan.
Specific therapy consists of oral administration of niacin amide from 100-300 mg daily in divided doses. The amide is preferable to nicotinic acid as the former does not cause unpleasant flushing and burning sensations that often results from taking nicotinic acid. Consumption of 125 gms of groundnuts per day supplies enough niacin to avoid pellagra. Niacin-fortified bread and maize-meals are also helpful.