500: DIAGNOSIS OF WERNICKE ENCEPHALOPATHY IN A PATIENT WITH UNDERLYING PSYCHIATRIC ILLNESS

Abstract

Introduction: Wernicke’s encephalopathy (WE) is an acute neuropsychiatric syndrome caused by thiamine deficiency. Common causes include alcohol use, bariatric surgery, and hemodialysis. Description: Our case involves a 65-year-old female who initially presented with seizure-like activity. Subsequent presentations over months included dysphagia, behavioral changes, and confusion. Initial workup with EEG, CT head, MRI brain, CT soft tissue neck, and endoscopy was unremarkable. Further history revealed that after her mother’s death four months prior, she began to self-isolate and reduce oral intake. Patient was evaluated by psychiatry and was diagnosed with conversion disorder. The clinical course was complicated by worsening neurological symptoms and respiratory distress requiring mechanical ventilation. Repeat MRI brain showed increased T2 FLAIR signal in the periaqueductal gray matter and along the dorsomedial thalamus consistent with WE. Patient was started on thiamine and showed symptomatic improvement. Discussion: WE is a triad of oculomotor dysfunction, ataxia, and confusion. In an observational study by Chamorro et al, 92.7% of cases were due to excessive alcohol intake, 47.1% due to malnutrition, and 5.9% due to psychiatric illness. The diagnosis of WE is primarily clinical, yet the classic triad is reported in only 10% of cases. The most consistent characteristic is a change in mental status. Caine et al developed the clinical diagnostic criteria, which include dietary deficiencies, oculomotor abnormalities, cerebellar dysfunction, and altered mentation or mild memory impairment. A case series based on this criteria found that clinical features of WE vary between alcohol and non–alcohol-related etiologies. The classic triad was more common in alcoholics than in non-alcoholics. One of the main challenges is the rate of underdiagnosis, which can be due to a lack of clinical suspicion or atypical presentation. Hence, MRI is a useful test to support the diagnosis of WE with a sensitivity of 53% and specificity of 93%. MRI may demonstrate lesions with increased symmetrical signal intensity in the periaqueductal region, medullary bodies, medial thalami, and the tectum of the midbrain. Diagnosis of WE should be considered in patients with psychiatric illnesses and atypical neurologic presentation.