[Pellagra: a clinical, histopathological, and epidemiological study of 7 cases]

In the developed world, pellagra is a rare condition that is restricted to a small number of at-risk groups. It mainly affects alcoholic patients and those with dietary deficiencies, with intestinal malabsorption, or in treatment with certain drugs. The aim of this study was to analyze the clinical, histopathological, and epidemiological characteristics of patients diagnosed with pellagra in our hospital and to compare the results with the findings traditionally described for this disease.

We undertook a retrospective study of patients with clinical or pathological evidence of pellagra who were seen in our hospital between 1998 and 2009.

Seven patients met the inclusion criteria. All were men and the most common predisposing factors were alcoholism and dietary deficiency. All exhibited photosensitivity mainly affecting the forearms and the upper surface of the feet, where the lesions were more severe. The most consistent histopathological findings were the presence of dilated blood vessels with extravasation and little or no inflammatory infiltrate. Various changes were observed in the epidermis, including those suggestive of mild pellagra, such as epidermal pallor and some degree of ballooning of the keratinocytes. Other abnormalities such as epidermal necrosis and hyperkeratosis were also observed. In most patients, pellagra was not initially suspected. Additional noncutaneous findings were observed in almost all cases.

Pellagra should be ruled out in patients with lesions on sun-exposed areas. Predisposing factors for pellagra should be assessed along with the social situation of patients and the presence of digestive or neurological abnormalities.