Correspondence

Sir-[Margaret Rayman]'s review1 on the importance of dietary selenium underlines the possible inverse correlation between low selenium status and the risk of cardiovascular disease, especially the cardiomyopathy associated with selenium deficiency in China (Keshan disease), where crops are raised on soils that are poor in this essential trace nutrient. Another clinical selenium deficiency arises in patients maintained on total parenteral nutrition (TPN) because of long-term management with nutritive fluid that is inadequate in selenium. Fleming and co-workers2 reported a man aged 24 years with chronic idiopathic intestinal pseudo-- obstruction who had been maintained on ITN for 6 consecutive years. Similarly, Johnson and colleagues3 described the case of a man aged 43 years who had been receiving TPN for 4 years after undergoing several gastrointestinal operations. These two patients died of a cardiomyopathy, which at necropsy bore a striking resemblance to the specific myocardial damage seen in Keshan disease.2,3 Extremely low concentrations of selenium (15-34% of normal) and selenium-dependent glutathione peroxidase activity (