The Pediatric Gastroenterology Unit of what was known as the Children’s Service at Massachusetts General Hospital was established in 1972. The unit’s first director, Allan Walker, MD, trained in Pediatrics and Immunology at the University of Minnesota Hospitals under Robert Good, MD. Since no pediatric gastroenterology (GI) training programs existed in 1969, Dr. Walker left pediatrics for three years to train as an adult GI fellow with Dr. Kurt Isselbacher on the Medical Service at Mass General.

Once established, the nascent Pediatric GI Unit received substantial impetus by aligning itself with the well-established and nationally recognized GI Unit of the Medical Services at Mass General. Pediatric GI fellows could take rotations in medical GI, attend and participate in weekly GI Grand Rounds and journal clubs as well as the weekly research conference. Since Pediatric GI had no NIH training grant at its beginning, Dr. Isselbacher graciously allowed the Pediatric GI fellows to be funded on his training grant during their two year period of research fellowship.

This close working relationship with Adult GI has continued to be a major strength of the Pediatric GI program at Mass General for Children and has led to many collaborations in both basic and clinical research over the years, most recently with the support of Dr. Daniel Podolsky, who followed Dr. Isselbacher as Chief of the GI Unit at Mass General and Dr. Ramnik Xavier, who has followed Dr. Podolsky. Since GI subspecialty patients frequently require ongoing care beyond the cut off period of 21 years for pediatrics, it is helpful to have transitional care by both pediatric and medical gastroenterologists until the patient adjusts to a new situation. This is done seamlessly and provides outstanding continuity of patient care at Mass General.

Over the next 10 years after its inception, the pediatric unit flourished. Pediatricians in training became aware of the potential of gastroenterology as a subspecialty and Pediatric Department chairmen recognized the expanding field required more expertise than that provided by the General Academic Pediatrician. In addition, specialized procedures (liver biopsy, endoscopy, pH probes, etc.) became part of the practice of gastroenterology and could only be done by specially trained pediatric gastroenterologists. With the recognition that many gastrointestinal and hepatic conditions occurred in the pediatric age period and were more complex than conditions encountered in adult GI medicine, many pediatricians, interested in the pathophysiology of disease, were attracted to choose pediatric gastroenterology as a subspecialty.

Accordingly, the Pediatric GI Unit at Mass General, because of the reputation of gastroenterology at the hospital and because of the emphasis on a physician/scientist approach to the subspecialty, attracted outstanding applicants wishing to enter the field as academic subspecialists.

Beginning in 1972, two pediatricians from various training programs in the United States and elsewhere were accepted into the program. These trainees entered a three-year training program consisting of one year of clinical rotations in Pediatric Gastroenterology followed by two years of laboratory research in an established laboratory of investigation that could enhance the fellows’ research expertise in related areas of interest. From the beginning, the overall theme of research under Dr. Walker’s supervision was developmental mucosal immunology, work that continues to this day.

In 1981, with the departure of Richard Grand, MD, from Children’s Hospital to direct Pediatric GI at Tufts New England Medical Center/Floating Children’s Hospital, Dr. Walker was asked by Mary Ellen Avery, MD, Chairman of Pediatrics at Children’s Hospital, and Donald Medearis, MD, Chairman of the Children’s Service at Mass General, to establish a Combined Program in Pediatric Gastroenterology at the two pediatric services at Harvard.

From 1981 until 2001, a Combined Program in Pediatric Gastroenterology existed. In this program, four to five fellows per year were accepted for a three-year period of clinical and research training.

In 1990, the first Pediatric Gastroenterology subspecialty board examination was held to certify pediatric gastroenterologists as boarded subspecialists. This required three years of clinical and research training, which included a continuity clinic to follow patients during the two research years. A committee of faculty (within and outside of Pediatric GI) was established to monitor the progress of the fellows during their research experience.

During the early 1990’s, Harvard established a Clinical Effectiveness Program as a partnership between its hospitals and the Harvard School of Public Health to train fellows of various subspecialties in clinical research. This program occurred in parallel within the two years of fellowship by clinically-oriented fellows and could result, if the fellow so desired and took subsequent classes, in a Masters of Science Degree from the Harvard School of Public Health. This program expanded the options for GI fellows and in some cases junior faculty to do either bench or clinical research as part of their fellowship.

The years of combined fellowship in Pediatric GI at Harvard allowed for an expanded faculty development. Ronald Kleinman, MD, one of Dr. Walker’s earliest fellows, became the Division Chief of the program at Mass General. A major renovation of the joint endoscopy suite allowed for expanded procedural options in both pediatric and adult gastroenterology. In addition, an active Liver Transplant Service was added, which broadened the Pediatric GI referral base. Mass General combined with the Brigham and Women’s Hospital to form Partner’s Health Care, which increased the referral base for pediatric patients, thus expanding the Pediatric GI services.

In 2001, Dr. Walker stepped down from his role as Chief of the Combined Program in Pediatric Gastroenterology to return to Mass General to expand the research facilities. He obtained 15,000 square feet of research space and expanded the Pediatric GI capacity to include eight Principal Investigators, 15 research fellows, (including two Pediatric GI fellows doing basic research) and several graduate students in Building 149 and Building 114 in the Charlestown Navy Yard (an expanded off campus research facility for Mass General).

From its inception as a Pediatric Unit to the establishment of a combined program and then two separate programs again in Pediatric GI (occurring in 2005), more than 100 Pediatric GI fellows have been trained in the Mass General program. Many of these fellows have established their own program in Pediatric Gastroenterology at medical schools throughout the United States, the UK, Europe, Australia and Asia. Almost 50 percent of trainees are still actively involved in clinical or basic research and more than 80 percent practice at academic centers.