Korsakoff Syndrome in a Late Adolescent with Wernicke Encephalopathy: A Case Report.

Introduction: Wernicke encephalopathy (WE) is a neurological emergency characterized by acute encephalopathy, oculomotor dysfunction, and ataxia, and may progress to Korsakoff syndrome - a disorder characterized by irreversible global episodic amnesia. Although classically linked to alcohol misuse, WE also arises in medical and psychiatric conditions associated with nutritional deficiency. Case Presentation: We report an 18-year-old male with schizophrenia, non-adherent to antipsychotic treatment, who was admitted with disorganization, catatonia, and dehydration. After several days of minimal nutrition (including dextrose-containing fluids), oral lorazepam, and intramuscular olanzapine, he developed acute WE with worsening catatonia. Intravenous thiamine and continued lorazepam rapidly improved his level of consciousness. Laboratory testing revealed undetectable thiamine, and MRI findings were consistent with WE. Despite oral multivitamin supplementation, catatonia improved only after escalation to intravenous lorazepam and electroconvulsive therapy. As catatonia improved, symptomatology of schizophrenia emerged and improved significantly with paliperidone therapy. As schizophrenia symptoms improved, complete anterograde and partial retrograde amnesia, apathy, and anosognosia emerged, consistent with Korsakoff syndrome. He continued to meet diagnostic criteria at 3-year follow-up. Conclusion: This complex case demonstrates the importance of maintaining a suspicion of thiamine deficiency in patients with a history of nutritional depletion of greater or equal to 2 weeks. Prompt initiation and continuation of thiamine therapy while investigating and treating concurrent diagnoses can reduce the risk of WE and Korsakoff syndrome.