RESUMO
BACKGROUND: Cancer patients submitted to gastrointestinal surgery are at risk of thiamine deficiency (TD) and Wernicke's encephalopathy (WE). Although permanent neurological damage and death could be prevented by a timely replacement therapy, they often remain undiagnosed and untreated. We hypothesized that WE remains unrecognized because most cases may manifest several months after hospital discharge. METHODS: WE frequency was investigated in a sample of cancer patients who underwent gastrointestinal surgery, by using the diagnostic criteria proposed to improve diagnosis among alcoholics. Patients were evaluated at discharge through the examination of medical records and 6 months after by telephonic interview. RESULTS: Forty-five patients were selected. Signs of WE resulted in 4.4% at discharge. At 6 months, 21 patients were interviewed. Among them, 90.4% had signs of WE. The number of affected patients was significantly higher 6 months after discharge than at discharge (90.4 vs 9.5%, p < 0.0001). CONCLUSIONS: Further studies with larger samples are needed to establish the prevalence of TD and related WE in cancer patients after gastrointestinal surgery. This study suggests that the problem is understated. Even in absence of symptoms of TD, the use of prophylactic thiamine supplementation should be taken in consideration, as consequences of misdiagnosis can be severe.