KorsakowSyndrom

Korsakoff syndrome (Korsakow-Syndrom in German) is a chronic neuropsychiatric disorder characterized by severe anterograde amnesia and confabulation, often following an episode of Wernicke encephalopathy. It is linked to long-standing thiamine (vitamin B1) deficiency in the context of alcohol use or malnutrition, which damages memory-related brain structures.

It is part of the Wernicke–Korsakoff syndrome spectrum. The core brain regions affected include the mammillary bodies and the dorsomedial thalamic nuclei, with secondary involvement of frontal circuits. Chronic alcohol use, poor nutrition, gastrointestinal diseases, HIV, and post-bariatric surgery can increase risk.

Symptoms include inability to form new memories (anterograde amnesia) with partial retrograde amnesia; confabulation and memory gaps; relatively preserved language, social skills, and procedural memory in early stages; disorientation; apathy; and difficulties in learning new information despite intact attention.

Diagnosis is based on clinical history, neuropsychological testing showing impaired new learning with preserved remote memory initially, and exclusion of other causes. Imaging may show mammillary body atrophy or thalamic changes; thiamine deficiency labs supportive but not diagnostic on their own.

Treatment and prognosis: urgent thiamine replacement during suspected Wernicke event, followed by ongoing supplementation; alcohol cessation and nutritional rehabilitation; cognitive rehabilitation and support for daily living. Prognosis varies; many patients retain severe anterograde amnesia; some gradual improvement can occur, but substantial deficits often persist.