All kinds of viral hepatitis (Chapter 42: The Liver: I. Structure & Function; Infections) are very common throughout the world, although the prevalence of Virus A hepatitis is greatest in developing countries. Chronic Virus B infection is most common in Far East Asia and Africa. Ethyl alcohol abuse is a worldwide problem (see Chapter 12: Disorders Due to Chemical Agents); in the United States, it is estimated that 10% of the population is affected by alcoholism. Liver and pancreatic disease are major complications of alcoholism (Chapters 43: The Liver: II. Toxic & Metabolic Diseases; Neoplasms and 45: The Exocrine Pancreas). Gallstone disease (Chapter 44: The Extrahepatic Biliary System) is common, particularly in middle-aged women.
The endocrine pancreas is discussed in this section rather than in the endocrine section because neoplasms of the islets of Langerhans enter the differential diagnosis of pancreatic tumors (Chapters 45: The Exocrine Pancreas and 46: The Endocrine Pancreas (Islets of Langerhans)). Diabetes mellitus (Chapter 46: The Endocrine Pancreas (Islets of Langerhans)) is a very common disease, affecting an estimated 2% of the population of the United States.