A Late Onset of Wernicke-Korsakoff Encephalopathy After Biliopancreatic Diversion: a Case Report

Wernicke-Korsakoff encephalopathy (WKE) is a neurologic disease due to a severe thiamine deficiency. This vitamin, an essential cofactor for cellular metabolism, is not produced by the human organism, so its total supply comes from diet, being absorbed from the duodenum. Wernicke described its acute onset in 1881; its classic form is characterized by the triad of ataxia, abnormal mental state, and ocular abnormalities (especially nystagmus). Although it is most commonly associated with chronic alcohol misuse (90% of all cases in USA), other medical conditions resulting in inadequate thiamine intake, such as gastrointestinal disease (vomiting, diarrhea), hyperemesis gravidarum, hemodialysis, sepsis, GI cancer, Crohn’s disease, psychiatric disorders, HIV infection, and malnutrition can determinate the onset of the disease. Another well-established cause of WKE is bariatric surgery. However, in most bariatric surgery-related cases, there were no specific neurological symptoms and no definitive neuroimaging markers were established. Moreover, a recent review upon the most common bariatric procedures showed that the large majority of cases develop in a range of onset between 4 and 12 weeks post-surgery (12 days up to 18 months). No significant difference in the time of onset in the different surgical procedures was observed. Roux-en-Y gastric bypass was the most related procedure (52%), followed by sleeve gastrectomy (21%); biliopancreatic diversion was associated with a small percentage of cases of WKE (3%). Biliopancreatic diversion is a single surgical procedure combining a sleeve gastrectomy and gut bypass, connecting the reduced stomach (about the 20% of the former organ) and the second tract of duodenum with the last part of the small intestine, with the aim to reduce calorie and nutrient absorption. Precipitating factors were persistent vomiting, diarrhea, rapid weight loss, anorexia, minimal food intake or glucose-containing intravenous feeding, alcohol misuse, and noncompliance with vitamin supplements.