# Gastric Bypass Presenting as Mixed Beriberi and Wernicke Encephalopathy

## TL;DR

A patient with a history of gastric bypass surgery developed severe thiamine deficiency presenting with neurological and cardiovascular symptoms, highlighting the need for early suspicion and treatment.

## Contribution

This case emphasizes the diagnostic challenge and importance of considering thiamine deficiency in post-bariatric surgery patients with atypical symptoms.

## Key findings

- The patient presented with mixed symptoms of beriberi and Wernicke encephalopathy due to severe thiamine deficiency.
- Empiric IV thiamine administration was initiated based on clinical suspicion before diagnostic confirmation.
- The case underscores the need for high clinical suspicion of vitamin deficiencies in post-gastric bypass patients.

## Abstract

Thiamine deficiency can lead to a spectrum of neurologic and cardiovascular manifestations, most notably beriberi and Wernicke encephalopathy. This condition is further separated into wet (cardiovascular manifestations) and dry (neurological manifestations) beriberi. Beriberi is often caused by a prolonged mild to moderate thiamine deficiency. In contrast, Wernicke encephalopathy occurs due to a severe, short-term thiamine deficiency that can present as the classic triad of mental status changes, ocular abnormalities, and gait ataxia. Since both conditions are due to the same cause of thiamine deficiency, they can coexist, but this often makes diagnosis more difficult, especially when findings are more subtle. We describe a 46-year-old female with a history of Roux-en-Y gastric bypass surgery who was admitted for non-infectious colitis and subsequently new-onset right lower extremity weakness and numbness, altered mental status, hypotension, and tachycardia. Empiric IV thiamine was initiated based on clinical suspicion despite an otherwise reassuring workup. She was later confirmed to have severe thiamine deficiency. This case highlights the importance of having high suspicion for vitamin deficiencies despite nonclassical symptoms.