Editorial: Seminars on liver disease: an introduction.

Hacki in the present issue of Yale Journal of Biology and Medicine is the first of a series of Seminars on Liver Disease which are to appear in successive issues of the Yale Journal. These papers by prominent investigators in the field of liver disease will have been presented at a series of seminars under the sponsorship of the Training Program in Liver Disease at the West Haven Veterans Administration Hospital during the months preceding publication. These seminars, which vary widely in subject material, are bound together by the common thread of interest in hepatology. Although the subjects may appear unrelated to each other, the liver is common and central to each. The liver is an organ with an almost infinite number of functions. Disorders of the liver result in disturbances of these diverse duties. The hepatologist or the physician sophisticated in the field of liver disease must not only be familiar with the clinical manifestations of cirrhosis, of hepatitis and of other common hepatic diseases , but he must be something of a biochemist, a virologist, a pharmacologist, and a pathologist. He might well have a sideline as a gastroenterologist, a radiolo-gist, or an endocrinologist. And a little nuclear knowledge never hurt neither. He must be able to understand and treat complications of liver disease which metastas-ize to a variety of other medical subspecialties. These areas include neurology (portal-systemic encephalopathy), gastroenterology (hemorrhage from esophageal varices, peptic ulcer), nephrology (the hepatorenal syndrome), endocrinology (diabetes, gynecomastia, testicular atrophy), infectious disease (viral hepatitis, spontaneous bacterial peritonitis), hematology (hypersplenism, hemochromatosis, impaired coagulation), oncology (primary and secondary tumors), immunology (chronic active hepatitis, drug-induced liver injury), and a number of others. The list of related disorders and clinical ramifications is almost endless. The complications , such as the hemosiderosis which follows portacaval anastomosis, are a separate medical world in itself. In addition, abnormalities of portal blood flow and the compensatory vascular changes of cirrhosis require an understanding of vascular physiology and catheter-ization techniques. The primary role of the liver in the metabolism of exogenous and endogenous substances, and the effects of enzyme induction on drug activation and detoxification demand knowledge about the biochemical processes of the liver. Recent appreciation of the micellar structure of cholesterol with bile acids, and its implications in the pathogenesis and therapy of cholelithiasis push hepatologists 145