After the great success of the fIrst issue of the series, the International Yearbook of Nephrology 1989, we were encouraged to proceed in our editorial venture to update nephrologists yearly, on all rapidly-changing areas of nephrology. Thus we have chosen new topics and appointed experts in the fIeld, asking them to give an objective review of the topic, up-dating the readers on the world-wide literature and providing them with a complete, accurate and up-to-date list of important, recent references. We have decided to maintain the successful format of the International Yearbook of...