Pellagra: a non-communicable disease of poverty.

Pellagra is a disease of poverty that is treatable but easily overlooked. The disease is caused by a deficiency of niacin and is clinically characterized by the triad of dermatitis, diarrhoea and dementia. We describe two cases of pellagra in a Malawian district hospital and discuss the pathogenesis, clinical manifestations and treatment of the disease.