RESUMEN
ABSTRACT: Wernicke encephalopathy (WE) results from thiamine deficiency. If undiagnosed or inadequately treated, WE evolves into Korsakoff syndrome (KS). We herein report a case of nonalcoholic Wernicke-Korsakoff syndrome (WKS) that resulted from malnutrition due to psychosis in a 42-years-old male patient. Thiamine deficiency was secondary to severe malnourishment due to poisoning delusions and daily life disorganization in a patient with previously unrecognized schizophrenia. Besides the presence of WE's classic triad of signs, brain magnetic resonance imaging showed also typical thalamic lesions. Furthermore, the patient also presented anterograde and retrograde amnesia, executive dysfunction, and confabulations, compatible with KS being already present. Intravenous treatment with thiamine was given for 37 days. Improvement in cognitive functions and brain imaging alterations was evident. Nevertheless, persistent WKS deficits were present. This case highlights the multiplicity of etiologies of WKS, namely, psychiatric, and its debilitating consequences if not promptly recognized and treated.