Common nutritional deficiency with unusual site of presentation

Abstract

Abstract Background Pellagra is a nutritional disorder due to deficiency of vitamin B3 (niacin) which is characterized by dermatitis, dementia, diarrhea, and death. The most common site of dermatitis in pellagra is the Casal necklace; however, in this case, the presentation of dermatitis is in unusual sites. Therefore, mucocutaneous signs play a major role in diagnosing the condition. The clinical features of pellagra begin with gastrointestinal symptoms followed by neurological symptoms which are subtle and non-specific. But if misdiagnosed and untreated, it can progress to death from multiorgan failure. Case presentation A 46-year-old Indian farmer, chronic alcoholic of 20 years duration, presented to the hospital with the complaints of darkening and thickening of the skin over the left upper chest and shoulder, epigastric region, left arm and forearm, and right arm and forearm for a period of 4 months with mild cognitive decline. His blood parameters revealed moderate anemia with microcytic hypochromic blood picture and decreased MCV, MCH, and MCHC values. A diagnosis of pellagra was built clinically after exclusion of other causes and has been treated with nicotinamide and had drastic improvement on follow-up. Conclusion The unusual site of pellagra presentation is rare; however, the uncommon presentation of a common disease is always to be considered for diagnosing the disease at the early stage. The neuropsychiatric symptoms of the pellagra in a known case of chronic alcoholic are not well defined, and if untreated, it may progress to stupor and coma and ultimately death. Hence, appropriate diagnosis and earlier management helps in the prevention of various life-threatening complications of any disease.