HDV (also known as the delta agent) is the causative virus of hepatitis D and is associated with both acute and chronic hepatitis. It is one of the most severe forms of chronic viral hepatitis. HDV is classified as a satellite virus, because it requires the presence of hepatitis B surface antigen (HBsAg) for its life cycle (see Chapter 79 ). Epidemiology HDV infection occurs worldwide.…
Acknowledgment The authors acknowledge the contributions of Drs. Heiner Wedemeyer, Jacqueline G. O’Leary, and Gary L. Davis to this chapter in previous editions of the book. More than 71 million people worldwide are chronically infected with HCV. , In the USA, conservative estimates suggest that more than 1.9 million people live with HCV. Unfortunately, HCV successfully evades the host immune response in 50% to 90% of…
Acknowledgment Drs. Jennifer T. Wells and Robert Perrillo contributed to this chapter in previous editions of the book. An estimated 260 million persons in the world today are chronically infected with HBV. The majority of these individuals will not experience complications, but 15% to 40% will have serious sequelae such as cirrhosis or HCC, and many will die prematurely. , It is estimated that chronic HBV…
Hepatitis A is the most common form of acute viral hepatitis worldwide. It is a self-limited infection caused by a non cytopathic, nonenveloped, single-stranded RNA virus that is transmitted primarily by the fecal-oral route by contaminated food or water and sometimes results in epidemic outbreaks. , HAV was first characterized in 1973, when scientists detected the virus in stools of human volunteers who were infected with…
Metabolic liver diseases may manifest as acute, life-threatening illnesses in the neonatal period or as chronic liver disease in adolescence or adulthood, with progression to liver failure, cirrhosis, or HCC. In a 2015 report of the Scientific Registry of Transplant Recipients, 13% of all liver transplants in the USA were performed because of complications resulting from metabolic liver disease. When the pediatric population alone was analyzed,…
Copper, a component of numerous essential enzymes, is toxic to cells when present in excess. Dietary intake of copper generally exceeds the trace amount required physiologically, and mechanisms to control influx and efflux from cells must maintain an appropriate balance. The 2 main human disorders of copper transport are Menkes disease , an X-linked defect in transport of copper from the intestine that leads to generalized…
Trousseau was the first to describe a case of hemochromatosis in the French pathology literature in 1865. Almost 25 years later, in 1889, von Recklinghausen, thinking that the disease was a blood disorder that caused increased skin pigmentation, introduced the term hemochromatosis (“blood color disease”). In 1935, Sheldon published a monograph describing all 311 cases of the disease that had been reported in the world’s literature…
Cirrhosis, a final pathway for a wide variety of chronic liver diseases ( Box 74.1 ), is a pathologic entity defined as diffuse hepatic fibrosis with the replacement of the normal liver architecture by nodules. The rate of progression of chronic liver disease to cirrhosis may be quite variable, from weeks in patients with complete biliary obstruction to decades in patients with chronic hepatitis C. Cirrhosis…
When appropriately ordered and interpreted, serum liver biochemical tests, the so-called “liver function tests” or “liver chemistries,” can be useful in the evaluation and management of patients with liver disorders. The term liver biochemical tests is preferable to liver function tests because the most commonly used tests—the aminotransferases and alkaline phosphatase—do not measure a known function of the liver. These tests have the potential to identify…
Hepatic parenchymal cells (hepatocytes and cholangiocytes) and nonparenchymal cells (hepatic sinusoidal endothelial cells, stellate cells, Kupffer cells, and pit cells) have distinct functions that are integrated through extensive cross-talk. These cells are highly polarized. The distinctive polarization pattern of hepatocytes is unique among glandular epithelial cells. Maintenance of hepatocyte polarization requires energy-consuming processes and is key to the wide array of liver functions. Hepatocytes are organized…
Embryology The liver develops at 3 to 4 weeks’ gestation as an outgrowing diverticulum of proliferating endodermal cells from the ventral wall of the foregut in response to signals from the adjacent developing heart ( Fig. 71.1 ). In the fourth week, 2 buds can be recognized in the hepatic diverticulum: the cranial bud becomes the liver and the hilar biliary tract, whereas the caudal bud…
Endoscopic therapy and radiologic treatment of biliary disease have evolved in separate but parallel manners. Endoscopic therapy is performed using ERCP and EUS-guided techniques. ERCP is performed primarily by endoscopists trained in a gastroenterology fellowship program, but in some centers it is performed by surgeons. ERCP is one of the most technically demanding endoscopic procedures, and for the successful management of complex cases the learning curve…
Acknowledgment This work was supported by grants from the NIH DK59427 (G.J.G.) and K08CA236874 (S.H.R.). Support was also provided to Dr. Rizvi by a Pilot & Feasibility Award by the Center for Cell Signaling in Gastroenterology (P30DK084567), and an AGA Research Scholar Award. Biliary malignancies comprise the vast majority of biliary neoplasms and are divided into 3 categories: (1) carcinomas of the intra- and extrahepatic bile…
Acknowledgments The authors acknowledge the contributions of Drs. Andrew S. Ross and Kris V. Kowdley to this chapter in previous editions of the book. Sclerosing cholangitis encompasses a spectrum of cholestatic conditions that are characterized by patchy inflammation, fibrosis, and destruction of the intrahepatic and extrahepatic biliary tract. These conditions are typically chronic, progressive disorders in which persistent biliary damage may lead to biliary obstruction, biliary…
Although gallstones and their complications account for most cholecystectomies, a consistent 15% of these operations are performed in patients without gallstones. In these patients, the majority of cholecystectomies are performed as treatment for 1 of 2 distinct clinical syndromes: acalculous biliary pain and acalculous cholecystitis. As shown in Table 67.1 , acalculous biliary pain is generally a disorder of young, predominantly female, ambulatory patients and mimics…
Many options are available for the treatment of patients with symptomatic gallstone disease. Improvements in endoscopic, radiologic, and chemical therapies for gallstones have enhanced the overall management of these patients. Nevertheless, surgery remains the most important therapeutic option. Laparoscopic cholecystectomy is the standard method for the management of patients with biliary pain and complications of gallstone disease, such as acute cholecystitis, gallstone pancreatitis, and choledocholithiasis (see…
Acknowledgment The authors acknowledge the contributions of Drs. Jeffrey D. Browning and Jayaprakash Sreenarasimhaiah to this chapter in previous editions of the book as well as the contributions of colleagues in the gallstone field. This work was supported in part by research grants DK54012, DK73917, DK101793, DK106249, DK114516, and AA025737 (D.Q.-H.W.) from the National Institutes of Health (U.S. Public Health Service). Cholesterol cholelithiasis is one of…
Bile formation is essential for intestinal lipid digestion and absorption, cholesterol homeostasis, and hepatic excretion of lipid-soluble xenobiotics, drug metabolites, and heavy metals. The process of bile formation depends on hepatic synthesis and canalicular secretion of bile acids, the predominant organic anions in bile, and maintenance of hepatic bile formation is essential for normal liver function. Bile acids also undergo an efficient enterohepatic circulation, with most…
Anatomy and Physiology The gallbladder is a distensible pear-shaped reservoir, the function of which is to store bile and deliver it to the duodenum for digestion (see Chapter 62 ). It is located along the undersurface of the liver and composed of 3 regions: the fundus, body, and neck. Gallbladder filling and emptying occur in both the interdigestive and postprandial periods. Emptying of bile into the…
In this chapter, the embryologic and anatomic characteristics of the bile ducts and gallbladder are reviewed, with a focus on information useful for diagnosing and treating biliary tract disease and understanding the anomalies and congenital malformations of these structures. Biliary tract disease in infants and children is considered because many of the disorders that occur early in life are due to abnormal morphogenesis or adversely affect…