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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.
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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.