The spectrum of biliary stone disease

Abstract

B iliary stone disease is a common problem in the United States and in most Western societies. It has been estimated from epidemiologic studies, both autopsy studies and clinical investigations, that gallstones are present in approximately 15 to 20 percent of adults; an incidence that begins in childhood and seems to progress steadily with age [I-3]. Gallstones are rare in children, begin to be identified in adolescence, have a marked increase in incidence between ages 35 and 55 years, and continue to show a gradual increase after 55 years of age. Estimates based on autopsy studies indicate that approximately 50 percent of elderly persons will have cholelithiasis by age 75. The incidence of gallstones is greater in females than in males and in patients who have had multiple pregnancies, and is slightly increased in obese patients. Studies of the natural history of gallstone disease indicate that from 40 to 60 percent of all persons with gallstones are asymptomatic [1,4,5]. In fact, it is probable that asymptomatic cholelithiasis may be the precursor of symptomatic cholecystitis in most patients. Some patients do, however, develop symptoms before gallstones can be identified; this occurs in approximately 5 percent of patients. In addition, some patients develop acute inflammatory biliary disease (acute acalculous cholecystitis) without gallstones. This syndrome most often occurs in elderly patients, in patients critically ill from another illness, or after major cardiovascular surgery or trauma. Of those patients who develop symptomatic cholecystitis, approximately 20 percent will present with acute cholecystitis, approximately 10 percent will have complicated cholecystitis (jaundice, cholangitis, or pancreatitis), and 60 to 70 percent will have symptoms of chronic cholecystitis. Of this latter group, up to 20 percent may have mild symptoms which are difficult to interpret. At the time of cholecystectomy, approximately 15 to 20 percent of patients studied carefully by routine intraoperative cholangiography or by intraoperative ultrasonography will be found to have common bile duct stones [a. This incidence again varies, depending on the age of the patient, the cause of the stones, and the diligence with which the surgeon looks for bile duct stones. Most of the stones found in the bile duct at the time of cholecystectomy will be similar to those found in the gallbladder, but in approximately 10 percent of patients the stones are dissimilar. In 1 to 2 percent of patients undergoing cholecystectomy, primary bile duct stones may be found without evidence of stones in the gallbladder. In these patients, the primary bile duct stones are usually due to stasis and