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Gastroenterology: An Introduction 1 1 Gastroenterology: An Introduction GASTROENTEROLOGY Gastroenterology (MeSH heading) is the branch of medicine focused on the digestive system and its disorders. Diseases affecting the gastrointestinal tract, which include the organs from mouth to anus, along the alimentary canal, are the focus of this speciality. Physicians practicing in this field are called gastroenterologists. They have usually completed about eight years of pre-medical and medical education, a year-long internship (if this is not a part of the residency), three years of an internal medicine residency, and two to three years in the gastroenterology fellowship. Some gastroenterology trainees will complete a “fourth-year” (although this is often their seventh year of graduate medical education) in transplant hepatology, advancedendoscopy, inflammatory bowel disease, motility or other topics. Hepatology, or hepatobiliary medicine, encompasses the study of the liver, pancreas, and biliary tree, and is traditionally considered a sub-specialty. Historical Background Extracting from Egyptian papyri, Nunn identified significant knowledge of gastrointestinal diseases among practising physicians 2 Clinical Gastroenterology during the periods of the pharaohs. Irynakhty, of the tenth dynasty, c. 2125 B.C., was a court physician specialising in gastroenterology, sleeping, and proctology. Among ancient Greeks, Hippocrates attributed digestion to concoction. Galen’s concept of the stomach having four faculties was widely accepted up to modernity in the seventeenth century. Fig. Illustration of the stomach, colon and rectum. Eighteenth century: • Italian Lazzaro Spallanzani (1729–99) was one of the early physicians to disregard Galen’s theories, and in 1780 he gave experimental proof on the action of gastric juice on foodstuffs. • German Johann In 1767, von Zimmermann on dysenterywrote an important work. • In 1777, Maximilian Stoll of Vienna described cancer of the gallbladder. Nineteenth century: • Philipp Bozzini In 1805, attempted first to observe inside the living human body using a tube he named Lichtleiter (light-guiding instrument) to examine the urinary tract, the rectum, and the pharynx. This is the earliest description of endoscopy. Gastroenterology: An Introduction 3 • Charles Emile Troisier described enlargement of lymph nodes in abdominal cancer. • William Prout in 1823, discovered that stomach juices contain hydrochloric acid. • William Beaumont in 1833, published Experiments and Observations on the Gastric Juice and the Physiology of Digestion following years of experimenting on test subjectAlexis St. Martin. • In 1868, Adolf Kussmaul, a well-known German physician, developed the gastroscope. He perfected the technique on a sword swallower. • In 1871, at the society of physicians in Vienna, Carl Stoerk demonstrated an esophagoscope made of two telescopic metal tubes, initially devised by Waldenburg in 1870. • In 1876, Karl Wilhelm von Kupffer described the properties of some liver cells now called Kupffer cell. • In 1883, Hugo Kronecker and Samuel James Meltzer studied oesophageal manometry in humans. Twentieth century: • In 1915, Jesse McClendon tested acidity of human stomach in situ. • In 1921-22, Walter Alvarez did the first electrogastrography research. • Rudolph Schindler described various important diseases involving the human digestive system during World War I in his illustrated textbook and is portrayed by some as the “father of gastroscopy”. He and Georg Wolf developed a semiflexible gastroscope in 1932. • In 1932, Burrill Bernard Crohn described Crohn’s disease. • In 1957, Basil Hirschowitz introduced the first prototype of a fibreoptic gastroscope. Twenty-first century: • In 2005, Barry Marshall and Robin Warren of Australia were awarded the Nobel Prize in Physiology or Medicine for their discovery of Helicobacter pylori(1982/1983) and its role in peptic ulcer disease. James Leavitt assisted in their 4 Clinical Gastroenterology research, but the Nobel Prize is not awarded posthumously so he was not included in the award. Understanding the Gastroenterologist A gastroenterologist requires to have a detailed understanding of the normal physiology of all the above mentioned organs as well as motility through the intestines and gastrointestinal tract in order to maintain a healthy digestion, absorption of nutrients, removal of waste and metabolic processes. A gastroenterologist also requires to have a clear understanding of ailments affecting the organs of the gastrointestinal system like: • peptic ulcer disease • gastric cancers • esophageal cancers • achalasia • Barret’s esophagus • colon polyps • colon and bowel cancers • pancreatitis • pancreatic cancers • cholecystitis • biliary tract disease • gallbladder stones and cancer • hepatitis • gastroesophageal reflux • colitis • nutritional problems and malabsorption, • Irritable Bowel Syndrome (IBS) • a host of other disease conditions. Training A Gastroenterologist must first complete a three-year Internal Medicine residency. He or she is then eligible for additional specialized training (fellowship) in Gastroenterology for two to three years. This means a total of 5-6 years of additional specialized Gastroenterology: An Introduction 5 education after medical school. The fellowship is a hands-on intense and rigorous programme that gives the opportunity to the trainee to learn directly from nationally recognized experts and work to get a detailed understanding of gastrointestinal diseases. Initiating from evaluation of patients to caring for them in the office as well as in the hospital is part of the training. Training involves learning endoscopy (upper endoscopy, sigmoidoscopy, and colonoscopy), endoscopic biliary examination (endoscopic retrograde cholangiopancreatography or ERCP), endoscopic mucosal resection or EMR, endoscopic ultrasound (EUS) etc. Along with endoscopy they are also trained in performing advanced endoscopic procedures such as polypectomy, esophageal and intestinal dilation and hemostasis. They are taught how to interpret imaging and pathology results in order to make appropriate recommendations to treat conditions. The fellowship is overseen by national societies like the American Board of Internal Medicine, the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. After completion of the fellowship the gastroenterologists are qualified to take the Gastroenterology board certification test administered by the American Board of Internal Medicine. Once they have successfully completed this examination they are “Board Certified.” Renewal of Certification Gastroenterologists renew their board certification through the American Board of Internal Medicine (ABIM) via the Maintenance of Certification (MOC) program. For this gastroenterologists require to schedule, take and pass the secure ABIM Gastroenterology Maintenance of Certification Examination as well as earn 100 points in Self-Evaluation of Medical Knowledge and Self-Evaluation of Practice Performance. In the latter test they are needed to earn a minimum of 20 points of medical knowledge and 20 points of practice performance. The remaining 60 points 6 Clinical Gastroenterology may be from either medical knowledge, practice performance or both. The ABIM Gastroenterology Maintenance of Certification Examination evaluates the knowledge and clinical judgment in relevant areas of practice. Exam questions are developed by a team of gastroenterologists in practice and in academic medicine. The computer-based examination is offered twice a year – in spring and fall. GI DISEASES At Gastroenterology Consultants we are dedicated to providing each patient with the individualized attention that you deserve. We provide each patient with state-of-the-art treatment methods that will help relieve the ailments and symptoms that you are experiencing. There are many different diseases and conditions that affect the overall health of the digestive system. The gastrointestinal tract is made up of the stomach and intestine and is often used to refer to all entities involved in the digestive tract from the mouth to anus. Ascites This condition is characterized by a buildup of fluid in the abdominal cavity, particularly within the peritoneal cavity that is located within the abdomen and the abdominal organs. A few of the most common signs of Ascites include swelling in the abdomen and the ankles, an increase in weight gain and also shortness of breath. Barrett’s Esophagus This is a precancerous condition that is characterized by the development of squamous cells that line the esophagus. Barrett’s Esophagus is generally the result of frequent manipulation and abuse to the esophageal lining, such as from chronic acid reflux or Gastroesophageal Reflux Disease (GERD). If left untreated, Barrett’s Esophagus could lead to esophageal cancer. Gastroenterology: An Introduction 7 Chronic Hepatitis C Hepatitis C is a blood-borne infection generally caused by a virus. This condition largely affects the liver, and is a very common infection among adults in the United States. Many patients that contract the disease do so through contact with infected blood via drug use, tattoos and sexual contact. Colon Cancer Cancer of the colon develops by the formation of malignant cancer cells within the large intestine. In many situations colon cancer is prompted by the development of polyps, noncancerous abnormalities that appear in the lining of