Pellagrous encephalopathy presenting as alcohol withdrawal delirium: a case series and literature review.

BACKGROUND: Alcohol withdrawal delirium (AWD) is associated with significant morbidity and mortality. Pellagra (niacin deficiency) can be a cause of delirium during alcohol withdrawal that may often be overlooked.

OBJECTIVES: We present a three-patient case series of pellagrous encephalopathy (delirium due to pellagra) presenting as AWD.

METHODS: We provide a brief review of pellagra's history, data on pellagra's epidemiology, and discuss pellagra's various manifestations, particularly as related to alcohol withdrawal. We conclude by providing a review of existing guidelines on the management of alcohol withdrawal, highlighting that they do not include pellagrous encephalopathy in the differential diagnosis for AWD.

RESULTS: Though pellagra has been historically described as the triad of dementia, dermatitis, and diarrhea, it seldom presents with all three findings. The neurocognitive disturbance associated with pellagra is better characterized by delirium rather than dementia, and pellagra may present as an isolated delirium without any other aspects of the triad.

DISCUSSION: Although endemic pellagra is virtually eradicated in Western countries, it continues to present as pellagrous encephalopathy in patients with risk factors for malnutrition such as chronic alcohol intake, homelessness, or AIDS. It may often be mistaken for AWD. Whenever pellagra is suspected, treatment with oral nicotinamide (100 mg three times daily for 3-4 weeks) prior to laboratory confirmation is recommended as an inexpensive, safe, and potentially life-saving intervention.