The Korean Journal of Internal Medicine is an international medical journal published in English by the Korean Association of Internal Medicine. The Journal publishes peer-reviewed original articles, reviews, and editorials on all aspects of medicine, including clinical investigations and basic research. Both human and experimental animal studies are welcome, as are new findings on the epidemiology, pathogenesis, diagnosis, and treatment of diseases. Case reports will be published only in exceptional circumstances, when they illustrate a rare occurrence of clinical importance. Letters to the editor are encouraged for specific comments on published articles and general viewpoints.