Bilateral hearing loss as the initial presentation of reversible Wernicke's encephalopathy with splenial lesion.

Background: Wernicke's encephalopathy (WE) is an acute neurological syndrome resulting from thiamine (vitamin B1) deficiency. It has been recognized increasingly in non-alcoholic patients, such as in the condition of malnutrition. Recent literature has shed light on uncommon symptoms and neuroimaging findings.

Case Report: We reported a case of a 44-year-old male who initially presented with bilateral hearing loss, and exhibited abnormality in the splenium of the corpus callosum on magnetic resonance imaging (MRI) diffusion-weighted imaging sequence. On the following day the patient developed new symptoms, including unstable walking, double vision and hallucination. The subsequent brain MRI demonstrated lesions involving periaqueductal grey matter and bilateral medial thalamus, indicating the diagnosis of WE. Empirical treatment with intravenous thiamine resulted in complete clinical and radiological resolution.

Conclusion: To the best of our knowledge, the current case is the first report of WE in literature with uncommon but reversible manifestations. This case warns us to maintain a heightened level of suspicion for WE in malnourished patients with neurological deficits, despite the possibility of atypical presentations encompassing bilateral hearing disturbances and unusual neuroradiological results. Early diagnosis and timely administration of thiamine in WE are likely to lead to a favorable outcome and full recovery.