Wernicke’s encephalopathy (WE) is an acute neurological condition caused by thiamine deficiency. The typical presentation is characterized by a triad of oculomotor abnormalities, gait ataxia, and altered mental status, though patients rarely present with all three symptoms. WE is a serious medical condition that is associated with high rates of morbidity and mortality if left untreated. It is most commonly seen in patients with severe alcohol use disorder; however, it has also been found in patients with thiamine deficiency due to other causes of malnutrition such as prolonged starvation, hyperemesis, dialysis, cancer, and geriatric surgery. Despite growing research demonstrating WE in non-alcoholic populations, it is frequently misdiagnosed in patients without an extensive alcohol-use history, particularly when they do not present with the typical clinical triad of symptoms. Thus, more knowledge about non-alcoholic WE is needed to improve diagnostic accuracy.

We present a case of a 26-year-old male with an unremarkable alcohol use history, who was diagnosed with WE following a 6-week period of excessive nausea and vomiting of unclear etiology. He presented to the ED three times prior to his diagnosis, and was treated with intravenous hydration, Zofran, and Pepcid. He presented to the ED for the fourth time with altered mental status and gait ataxia and was diagnosed with WE based on MRI findings. He was admitted and treated with high doses of IV thiamine and folate. His clinical course was tracked over time via outpatient neurology examinations, and his cognitive functioning was assessed with an outpatient neuropsychological evaluation approximately six months post-discharge. Record review, including clinical notes, lab tests, and imaging results supplement his outpatient neuropsychological evaluation performance.

Data from a comprehensive outpatient neuropsychological evaluation approximately six months after WE diagnosis is presented. His cognitive profile was characterized by impaired performance on measures of verbal fluency and memory, including encoding and retention of verbal and visual information (with minimal benefit from cueing). Given these impairments and continued functional declines related to cognitive deficits, he met criteria for a Major Neurocognitive Disorder. These results demonstrate persistent cognitive deficits beyond the acute WE period.

WE is a serious neurological condition that can have lasting cognitive effects if left untreated. This case demonstrates persistent cognitive impairments six months after WE diagnosis in a young patient with an unremarkable alcohol history. These findings highlight the necessity of increased diagnostic efficiency of WE in non-alcoholic patients, as immediate thiamine treatment is essential to the recovery process. Neuropsychological functioning at a longer interval will be useful in further elucidating cognitive prognosis as well as providing quality of life recommendations.