Pellagra Post–Roux-en-Y Gastric Bypass Surgery

BACKGROUND/OBJECTIVE: Micronutrient deficiencies such as pellagra are rarely seen after bariatric surgery and can be challenging to diagnose and manage. Alcohol use can precipitate nutritional deficiencies. CASE REPORT: A 51-year-old woman with a history of Roux-en-Y gastric bypass surgery who later developed an alcohol-use disorder after her diagnosis of breast cancer. She experienced a subacute decline in her physical and cognitive function along with a rash after radiation treatment for breast cancer, lower extremity pain and weakness, anemia, and diarrhea with severe hypokalemia. Workup showed undetectable niacin levels. She initially did not respond to an oral niacin replacement, necessitating intramuscular injections. Alcohol cessation and parenteral B complex replacement led to the resolution of her symptoms and biochemical derangements. DISCUSSION: Bariatric surgery with concomitant alcohol use can precipitate niacin deficiency–induced liver dysfunction. In the correct clinical setting, screening for alcohol use and checking niacin levels may help avoid extensive testing and can help make the correct diagnosis. Parenteral replacement may be necessary in this setting. CONCLUSION: Niacin deficiency needs to be considered in patients with bariatric surgery with a history of alcoholism in the correct clinical setting.