What is a Gastroenterologist?

A gastroenterologist is a medical professional who specializes in the treatment of diseases and conditions affecting the digestive system. Gastroenterology is a subspecialty of internal medicine (What is a Gastroenterologist?).

The work of a gastroenterologist goes beyond just the stomach. The digestive system is comprised of the stomach, esophagus, small and large intestines and a series of organs and ducts called the biliary system (the gall bladder, pancreas, liver, and bile ducts). Gastroenterologists are also concerned with the digestion and motility of food, or how food is broken down in the digestive tract and how it moves through (What is a Gastroenterologist?). Gastroenterologists must be able to not only correctly identify ailments of these organs and systems, but treat and care for them as well.

Due to the wide variety of conditions and diseases that gastroenterologists treat, the patients that these specialists treat vary greatly as well. Gastroenterologists see everyone from children (pediatric gastroenterologists) to elderly patients and treat conditions as mild as heartburn to more severe issues such as Crohn’s Disease and hepatitis. Gastroenterologists may provide their services in an office environment, in a hospital, or may visit patients in other medical environments. (What is a Gastroenterologist?).

Gastroenterologists may choose to focus their career further with a subspecialty in hepatology. Hepatology is the field of medicine concerned specifically with the “liver, pancreas and biliary tree” (Gastroenterology.) Gastroenterologists may also choose to focus their careers specifically on research.

Selected History of Gastroenterology

The inner workings of the human body have been studied and theorized about since the early Egyptians and Greeks. Papyrus scrolls dating back to the 10th century B.C. document a court physician by the name of Irynakhty serving Pharaoh Merykare. Irynakhty “conducted experiments by feeding subjects a variety of diets and observing the effects it had on moods, behavior and health.” (Ardis, 2015). Irynakhty appears to be the first to explore gastroenterology specifically.

For centuries, it was believed that blood was produced exclusively in the liver, a theory that was part of the Hippocratic theory of medicine called Humorism (Humorism). It was the Greek physician, writer and philosopher Galen of Pergamum who specifically identified the four humors and their purposes, claiming “the liver and veins were responsible for nutrition and growth” (Galen of Pergamum). This was the prevailing theory until the 19th century, when advances in medicine and science by many had by and large disproved the theory (Humorism).

Advances specific to gastroenterology began in the 19th century. In 1806 Philipp Bozzini (1773 -1809) made a huge contribution with the invention of his Lichtleiter. The Lichtleiter was a small light conductor that allowed visibility into the body of a live patient, overcoming the obstacles of endoscopy at the time: light, optics and handling (Figdor, 2004). Adolf Kussmaul is credited with attempting the first gastroscopy in 1868, though unsuccessful due to the fact that the stomach is not straight and it was not possible at the time to get a light into the stomach without cutting it open (Sivak, 2006). The first flexible gastroscope was invented in 1911 by Georg Wolf (1873 – 1938) in Germany (Endoscopy). The gastroscope would evolve into the endoscope, a staple of gastroenterologists, several times again over the course of the next 75 years between advances in technologies and techniques (Sivak, 2006).

Walter Alvarez performed the first electrogastrograph in 1921 by attaching electrodes to the stomach of a “little woman” and studying the myoelectrical behavior of the stomach. He theorized that the gastric activity in the stomach was due to myoelectric behavior, therefore gastric disturbances could have a myoelectric cause, which could be diagnosed (van der Schee, 1984).

In 1932 Dr. Burrill Bernard Crohn, Dr. Gordon David Oppenheimer, and Dr. Leon Ginzburg presented a paper to the American Gastroenterological Association on a new disease they believed they had identified, which they had termed regional ileitis. The disease had some similarities to bowel tumors and strictures, however many symptoms differed. This disease, much to the chagrin of Dr. Crohn, would quickly come to be known a Crohn’s disease (de Campos, Kotze, 2013).

The American Society for Gastroenterological Endoscopy was formed in 1941. Today it has of 15,000 medical professionals as members and its mission statement is “to be the leader in advancing patient care and digestive health by promoting excellence and innovation in endoscopy” (About ASGE).

In 1970 and 1971, after noticing many non-member attendees at ASGE conferences, Mirna L. Schirmer, RN, reached out to gastroenterologists asking for the names of nurses assisting in their procedures. Through correspondence these nurses exchanged ideas and experience in the profession of gastroenterological nursing and surgical assisting. At the 1973 ASGE conference, the nurses were provided a space to convene, at which 90 people attended and a name was given to their organization. The Society for Gastrointestinal Assistants was founded, and their first annual meeting was held in 1974. In 1989, the name of the society was changed to The Society for Gastrointestinal Nurses and Associated to better reflect those involved in the society (About SGNA).

In 2005 J. Robin Warren and Barry J. Marshall won the Nobel Prize in Physiology or Medicine “for their discovery of the bacterium Helicobacter pylori and its role in gastritis and peptic ulcer disease” (Nobel Media AB 2014, The Nobel Prize in Physiology or Medicine 2005).

How to Become a Gastroenterologist (How to Become a Gastroenterologist)

As with all medical specialties, a specialization in gastroenterology begins with a four-year undergraduate degree from an accredited institution with a focus in biology, anatomy or chemistry. Many schools offer a “pre-med” program with a curriculum that has been selected specifically for those who wish to pursue an advanced degree in medicine.

Students must also take the Medical College Admission Test (MCATs). Required scores are dependent on the school at which one is applying and the test is usually taken during a students’ junior year of undergraduate study.

The four-year undergraduate degree is followed by a three-year or four-year medical degree from an accredited institution.  This degree program is comprised of both classroom education as well as clinical rotation, where a student will gain hands-on experience interfacing with patients, diagnosing conditions, and gaining exposure to a variety of specialties. The medical school training may or may not include an internship.

Once medical school is complete graduates must pass their Board Examinations to demonstrate knowledge of the concepts, principles and skills required to practice in the medical profession. Board examinations are administered by the National Board of Medical Examiners and passage of the exams is required to practice medicine.

Upon passage of the board examinations, a graduate may become a resident at a medical facility. Those interested in pursuing a specialty in gastroenterology would select a residency focusing on internal medicine to gain in depth knowledge how the human body works to prepare them for further training. Residencies last anywhere from two to three years and may include classroom training as well as practical and clinical exposure.

For gastroenterologists, residency is followed by a fellowship. This three-year fellowship will give the doctor specific training in gastroenterologic and hepatic medicine and allow them to focus their training. The fellowship will include at least 18 months of hands-on patient interaction.

At the end of the fellowship the doctor will take another round of board examinations to demonstrate their abilities and knowledge in the specialty of gastroenterology. These exams are administered by the American Board of Internal Medicine. Note that gastroenterologists must first become certified in internal medicine before they may pursue a certification in gastroenterology. Once certified, doctors may begin practicing.

In the pursuit of their careers, gastroenterologists are required to continue their education, keeping their licenses and certifications current. They may also elect, and are encouraged, to join professional organizations to share knowledge and network with others..

Diseases and Conditions Gastroenterologists Treat

As mentioned before, gastroenterologists treat a multitude of diseases and conditions. For example, patients might seek the aid of a gastroenterologist for the treatment of heartburn, unexplained weight loss, hemorrhoids, hernias, upset stomach, and ulcers. Gastroenterologists would also be called to diagnose gall bladder disease, cancers of the stomach, esophagus, or intestines, treat bleeding in the stomach or a digestive tract organs, address malabsorption conditions such as lactose intolerance or celiac disease, and treat diverticular disorders such as Crohn’s disease or irritable bowel syndrome (IBS) (What is Gastroenterology).

Hepatologists, as stated earlier, are specialists within gastroenterology who focus on the liver, gall bladder, pancreas, and biliary tree. They may be able to treat or diagnose the above issues but are generally focused on treating diseases and conditions such as hepatitis (A, B, and C), fatty liver disease, cirrhosis, liver cancer, genetic liver diseases, enzyme defects in children, pancreatitis, liver transplantation, and infections (Robertson, 2014).

Schools for Gastroenterology (Gastroenterology Medical Schools)

There are a number of schools in the United States and Puerto Rico that offer a focus in gastroenterology. Below is an alphabetical list of 21 schools with this offering. Note, this article offers no ranking or other ordering of these schools other than an alphabetical listing.

Charles R. Drew University of Medicine and Science, Charles R. Drew University – Los Angeles, California

Johns Hopkins School of Medicine – Baltimore, Maryland

Maryland School of Medicine, University of Maryland – Baltimore, Maryland

Oklahoma College of Medicine, University of Oklahoma Health Sciences Center – Oklahoma City, Oklahoma

Penn State Hershey College of Medicine, Pennsylvania State University Hershey – Hummelstown, Pennsylvania

Rutgers New Jersey Medical School – Newark, New Jersey

San Juan Bautista School of Medicine – Caguas, Puerto Rico

Stony Brook School of Medicine, State University New York Stony Brook – Stony Brook, New York

Tufts University School of Medicine – Boston, Massachusetts

UMASS School of Medicine, University of Massachusetts Worchester – Worchester, Massachusetts

Uniformed Services University of the Health Sciences – Bethesda, Maryland

University of California San Diego School of Medicine – La Jolla, California

University of Cincinnati Academic Health Center – Cincinnati, Ohio

University of North Carolina School of Medicine – Chapel Hill, North Carolina

University of Texas Southwestern Medical School – Dallas, Texas

University of Wisconsin School of Medicine – Madison, Wisconsin

Vermont College of Medicine, University of Vermont & St. Agric College – Burlington, Vermont

Wake Forest University School of Medicine, Wake Forest University – Winston-Salem, North Carolina

Warren Alpert Medical School, Brown University – Providence, Rhode Island

Washington University School of Medicine – Saint Louis, Missouri

Wayne State School of Medicine, Wayne State University – Detroit Michigan

Gastroenterology Statistics

  • As of 2015, there are approximately 14,126 gastroenterologists in the United States: 13,014 in patient practice, 190 in teaching positions, 293 in research, and 629 in other focuses. The total number of practitioners is up 9.9% since 2010 (Association of American Medical Colleges).
  • In 2009 – 2010, 51 million people in the United States visited a medical facility for a digestive system condition as the primary diagnosis. This included primary care physician’s offices, hospital outpatient centers, and emergency rooms (Centers for Disease Control and Prevention (a)).
  • As of 2015 there were 14.8 million people in the United States living with ulcers (Centers for Disease Control and Prevention (a)).
  • In 2014, 38,170 people in the United Stated died from cirrhosis or chronic liver disease (Centers for Disease Control and Prevention (b)).
  • The United States will need a 10% increase in gastroenterologists by 2020 due to the increasing need for cancer screenings (HEALTHeCAREERS Network 2014 Gastroenterology Employment Fact Sheet).
  • An estimated 50,310 people died of colorectal cancer in the United States in 2014 – 26,270 men and 24,040 women (Siegel, DeSantis, Jemal, 2014)

Focuses and Advancements in Gastroenterology in Today’s Medicine

Gastroenterology is playing an ever increasingly important role in a variety of medical fields. Myriad diseases once thought to afflict only certain parts of the body are now seeing symptoms displayed in parts of the gastrointestinal tract and are requiring the assistance of gastroenterologists in diagnosis and treatment.

It is now becoming much more apparent that mitochondrial disorders (MIDs) affect the gastrointestinal tract far more frequently than previously thought (Finsterer, Frank, 2016). Symptoms such as vomiting, constipation, pancreatitis, hepatopathy (any disease of the liver), or dysphagia (difficulty swallowing) are just some of the conditions that should be considered when considering a diagnosis of MID (Finsterer, Frank, 2016). This conclusion, gaining traction in 2016, seeks to demonstrate that MID diagnoses are far more complex and interconnected and conditions need to be reviewed globally.

Irritable bowel syndrome with diarrhea has become a hot button issue in recent years. The symptoms and effects of this disease are not only physical, but social and psychological, so it’s no wonder there’s a large market for companies to try to cash in on trying to ease and treat the symptoms of this GI disease.  There are, however, many doctors who do, in fact, want to help patients who suffer from this condition.

In 2015, the FDA approved two new drugs to treat IBS-D, rifaximin (known commercially as Xifaxan) and eluxadoline (known commercially as Viberzi) (United States Food & Drug Administration, 2015). These drugs added to the availability of treatments for IBS-D sufferers, where previously the only available pharmaceutical treatment was alsetron (known commercially as Lotronex) and was only available for women who had more severe symptoms (Lucak, Chang, Halper, Harris, 2016). The addition of these two symptoms has widened the availability of treatment for all patients who suffer from this condition.

Biliary tract cancer (BCT) is a rare form of cancer that affects roughly 8,000 people in the United States each year (American Cancer Society). With survival rates as low as 15-30% early detection for this cancer is one of the most important steps to beating it. Recent advancements in “genomic profiling and bioinformatics” have led to the development of treatments that attempt “targeted therapies and immunotherapies” aimed at treating this disease (Lee, Ross, 2017).

On April 16, 2016, the FDA approved the first blood-based colon cancer screening test, Epigenomics’ Epi proColon. This is the first screening method available for colorectal cancer (CRC) that does not involve a fecal immunochemical test (FIT) or colonoscopy. It is a simple blood screening available at a healthcare provider (Vaidya, 2016).

In 2016, the FDA approved Ocaliva (obeticholic acid), an oral therapy used for the treatment of primary biliary cholangitis (United States Food & Drug Administration, 2016). This treatment benefits up to half of the 40% of patients who did not find success with ursodeoxycholic acid (Ali, Lindor, 2016). While admittedly not the perfect solution, the addition of this option widens the availability of relief significantly to sufferers of this condition.

Exciting gastroenterological news out of Korea in 2016: the development of the first artificial liver was announced. The liver was based on a pig’s liver, and can be used for human transplantation. The need for human liver is high in Korea, as liver cancer is the leading cause of death among Korean’s in their 40’s and 50’s (Korean Bizwire).

Societies and Networking Communities for Gastroenterologists and Gastroenterological Medical Professionals

Gastroenterologists and related medical professionals are encouraged to join professional communities to share knowledge and to aid in their continued education. These groups often offer conferences and seminars, publish journals, and provide member lists for the edification of their members. Most groups boast memberships from around the world. Many doctors seek memberships in multiple organizations.

American College of Gastroenterology was founded in 1932. It has a current membership of over 13,750 medical professionals in 86 countries. It’s flagship publication is the clinical journal The American Journal of Gastroenterology and the ACG moved to its new headquarters in Bethesda, Maryland in February 2015 (American College of Gastroenterology).

American Gastroenterological Association was founded in 1897 and has a current membership of over 16,000 members from around the world in a variety of fields of medicine and science. This organization publishes 3 monthly journals: Gastroenterology, Clinical Gastroenterology and Hepatology, and Cellular and Molecular Gastroenterology and Hepatology. The AGA’s annual conference is Digestive Disease Week, held every May, and is “the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy, and gastrointestinal surgery” (American Gastroenterological Association).

As mentioned earlier, American Society for Gastrointestinal Endoscopy was founded in 1941 and today has over 15,000 members around the world. This group is focused more specifically in the specialty of endoscopy, which is extremely important to the field of gastroenterology. ASGE offers and promotes a number of publications to its members through its website, and offers many calendar events around the country (About ASGE).

The Society for Gastroenterology Nurses and Associated boasts over 8,000 members today and publishes Gastroenterology Nursing. This organization offers a certification program for nurses, with its first round of over 650 nurses being certified in gastroenterology nursing in 1986. The SGNA also organizes the annual GI Nurses and Associates Week to celebrate those working in the field (About SGNA).

The Canadian Association of Gastroenterology was founded in 1962 and currently has over 1,100 members comprised of gastroenterologists, scientists, pediatricians and surgeons. Much of this organizations aim is to raise funds for research and education, with their leading program being the Industry Research Program, in partnership with the Canadian Institutes of Health Research (CIHR). This group offers continuing education opportunities for practicing medical professionals as well as training opportunities for students, and hosts its own Canadian Digestive Diseases Week (similar to that of the AGA) (Canadian Association of Gastroenterology).

The Gastroenterological Research Group was formed in 1955 by a group of doctors not satisfied by the opportunities and resources available for gastroenterological research. This organization sponsors conferences, offers grants and awards for research, supports up-and-coming researchers, promotes the education of young researchers (both MDs and PhDs), and recruits for new professionals in the field or research gastroenterology. The official journal of the GRG is Digestive Diseases and Sciences (Gastroenterology Research Group).

Gastroenterology in the Future

Gastroenterology is as in demand now as any other specialty, and its need is only going to grow. With the population living longer and longer, the need for medical professionals who not only can treat the ailments of the digestive system but can cure and prevent these diseases is profound. Patient care, research, collaboration and innovation are going to be at the forefront of this specialty moving ahead.


About ASGE (n.d.). American Society for Gastroenterological Endoscopy. Retrieved from https://www.asge.org/home/about-asge

About SGNA (n.d.). Society for Gastrointestinal Nurses and Associated. Retrieved from https://www.sgna.org/About/About-SGNA

Ali, A.H., Lindor, K.D. (2016. August 9). Obeticholic acid for the treatment of primary biliary cholangitis. [Abstract]. PubMed.Gov. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/27468093#

American Cancer Society. (2016, January 1). What are the key statistics about bile duct cancer? Retrieved from https://www.cancer.org/cancer/bile-duct-cancer/about/key-statistics.html

American College of Gastroenterology. (2017). Media. Retrieved from http://gi.org/media/

American Gastroenterological Association. (2017). About AGA. Retrieved from http://www.gastro.org/about

Ardis, A. (2015, October 20). A History of Gastroenterology. Retrieved from http://ezinearticles.com/?A-History-of-Gastroenterology&id=9203717

Association of American Medical Colleges. (2015, December). 2016 Physician Specialty Data Report. Retrieved fromhttps://www.aamc.org/data/workforce/reports/457712/2016-specialty-databook.html

Canadian Association of Gastroenterology. (2016). What is the CAG? Retrieved from https://www.cag-acg.org/about/what-is-the-cag

Center for Disease Control and Prevention (a). (2017, March 31). Digestive Diseases. Retrieved from https://www.cdc.gov/nchs/fastats/digestive-diseases.htm

Center for Disease Control and Prevention (b). (2016, October 6). Chronic Liver Disease and Cirrhosis. Retrieved from https://www.cdc.gov/nchs/fastats/liver-disease.htm

de Campos, F.G., Kotze, P.G. (2013). Burrill Bernard Crohn (1884 – 1983): The Man Behind the Disease. Brazilian archives of digestive surgery. 2013; 26(3). pp 253 – 255. Retrieved from https://www.researchgate.net/publication/260130906_Burrill_Bernard_Crohn_1884-1983_the_man_behind_the_disease

Endoscopy. (2017, May 25). In Wikipedia. Retrieved May 30, 2017 from https://en.wikipedia.org/wiki/Endoscopy

Figdor, P. (2004) [excerpt]. A few words of introduction on the celebration marking the return of Bozzini’s light conductor to Vienna. In: The Development of Endoscopy in the 19th Century, Vol 3., Tuttlingen, 2004. Retrieved from http://history.uroweb.org/history-of-urology/diagnosis/looking-into-the-body/bozzini-and-the-lichtleiter/

Finsterer, J., Frank, M. (2016, October 5). Gastrointestinal manifestations of mitochondrial disorders: a systematic review. Sage Journals, Vol 10, Iss 1, 2017. Retrieved from http://journals.sagepub.com/doi/full/10.1177/1756283X16666806

Galen of Pergamum. (2017, March 10). In Encyclopædia Britannica. Retrieved May 30, 2017 from https://www.britannica.com/biography/Galen-of-Pergamum

Gastroenterology (n.d.) In Wikipedia. Retrieved May 28, 2017 from https://en.wikipedia.org/wiki/Gastroenterology

Gastroenterology Medical Schools (n.d.) Retrieved on May 28, 2017 from http://medical-schools.startclass.com/d/b/Gastroenterology

Gastroenterology Research Group. (n.d.) The GRG Mission. Retrieved from http://gastrodev.org/grg/

HEALTHeCAREERS Network 2014 Gastroenterology Employment Fact Sheet. (2014, May 2). American Gastroenterological Association. Retrieved from https://www.healthecareers.com/aga/article/healthecareers-network-2014-gastroenterology-employment-fact-sheet/174799?type=email&source=aga-eDigest-06-14

 How to Become a Gastroenterologist. (n.d.). Retrieved from http://study.com/articles/How_to_Become_a_Gastroenterologist_Education_and_Career_Roadmap.html

Humorism. (2017, May 24). In Wikipedia. Retrieved May 30, 2017 from https://en.wikipedia.org/wiki/Humorism

Korean Bizwire (2016, December 27). Scientists Develop Artificial Liver for Human Transplant. Retrieved from http://koreabizwire.com/scientists-develop-artificial-liver-for-human-transplant/72950

Lee, H., Ross, J. (2017, March 28). The potential role of comprehensive genomic profiling to guide targeted therapy for patients with biliary cancer. Sage Journal, Vol 10, Iss 6, 2017. Retrieved from http://journals.sagepub.com/doi/full/10.1177/1756283X17698090

Lucak, S., Chang, L., Halpert, A., Harris, L. (2016, August 28). Current and emergent pharmacologic treatments for irritable bowel syndrome with diarrhea: evidence-based treatment in practice. Sage Journals, Vol 10, Iss 2, 2017. Retrieved from http://journals.sagepub.com/doi/full/10.1177/1756283X16663396

Nobel Media AB 2014. The Nobel Prize for Physiology or Medicine 2005. Nobelprize.org. Retrieved from https://www.nobelprize.org/nobel_prizes/medicine/laureates/2005/

Robertson, S. (2014, November 19). What is Hepatology? Retrieved from http://www.news-medical.net/health/What-is-Hepatology.aspx

Siegel, R., DeSantis, C., Jemal, A. (2014, March 17). Colorectal Cancer Statistics, 2014. CA: A Cancer Journal for Clinicians, Vol 64, Iss 2, Mar/Apr 2014, pp 104 – 117. Retrieved from http://onlinelibrary.wiley.com/doi/10.3322/caac.21220/full

Sivak, M.V. (2006, August). Gastrointestinal endoscopy: past and future. Gut. 2006; 55(8). pp 1061 – 1064. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856274/

United States Food & Drug Administration. (2015, May 27). FDA approves two therapies to treat IBS-D. [Press Release]. Retrieved from https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm448328.htm

United States Food & Drug Administration. (2016, May 31). FDA approves Ocaliva for rare, chronic liver disease. [Press Release]. Retrieved from https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm503964.htm

Vaidya, A. (2016, April 16). FDA approves 1st CRC screening blood test: 4 notes. Becker’s GI & Endoscopy. Retrieved from http://www.beckersasc.com/gastroenterology-and-endoscopy/fda-approves-1st-crc-screening-blood-test-4-notes.html

van der Schee, E.J. (1984). Electrogastrography: Signal Analytical Aspects and Interpretation. Retrieved from https://books.google.com/books/about/Electrogastrography.html?id=iKqCGwAACAAJ

What is a Gastroenterologist? (2008, February 29). Retrieved from http://www.healthcommunities.com/general-gi-symptoms/what-is-a-gastroenterologist.shtml

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