What is the basic anatomy and physiology of the gastrointestinal (GI) tract (important in understanding intestinal failure and intestinal transplant)?

The gastrointestinal tract begins at the mouth where mechanical digestion begins. Saliva in the mouth functions to moisten and lubricate food before swallowing, as well as to partially digest food particles. Food moves from the mouth, down the esophagus, and into the stomach. In the stomach, glands secrete hydrochloric acid, which helps to digest food and destroy bacteria that enters the body with the food. Other than water, little nutrient absorption occurs in the stomach. The digested particulate matter, known as chyme, moves from the stomach into the first portion of the small intestine known as the duodenum. It is in the small intestine where most of the digestion and absorption of food occurs. Special enzymes breakdown carbohydrates, fat, and proteins into smaller components that the intestinal cells can absorb and use throughout the body for nutrients. The pancreas and liver also secrete substances into the small intestine to aid in the digestion of substances. Food then passes through the entirety of the small intestine, through the duodenum, the jejunum, and the ileum. Next, food enters the colon, which serves two leading roles: acts as a storage chamber for undigested material and functions to reabsorb water. When initiated, contractions of the rectum and relaxation of the anal sphincter cause defecation, and stool is deposited. Digestion and absorption rely on many components of proper contractions, enzymes, and cell function. If any of these functions are impaired, then the process may not proceed as planned, as seen in patients with intestinal failure.

What intestinal disorders may result in intestinal failure and the need for an intestinal or multivisceral transplant in adults?

Intestinal Failure (IF) can develop when a person's small intestine does not provide the necessary long-term nutrition needed to sustain a normal life. This leads to the need for additional long-term nutrition to be delivered through large veins in the body. This is called "Parenteral Nutrition" or "PN." Causes of Intestinal Failure that Can Lead to Failed PN and Intestinal Transplant Motility Disorders:

• Chronic Intestinal Pseudo-Obstruction (CIPO), Global Dysmotility, Gastroparesis

At what point might an intestinal or multivisceral transplant be recommended?

If an individual's small bowel has permanently failed, also known as intestinal failure, he or she may require an intestinal transplant. Intestinal failure is when the intestine is not able to digest and absorb enough nutrients to support growth and daily function. Individuals with intestinal failure require the use of parenteral nutrition, or PN, which is the delivery of nutrients through the large veins in his or her body. Intestinal failure alone is not an indicator for intestinal transplant; instead, an individual must also have a complication from total parenteral nutrition (PN), as noted below. It is usually from the long-term use of PN in which these issues occur. Please note: Every case is reviewed on an individualized basis. While PN failure is the Centers for Medicare and Medicaid standard, your team may be able to appeal your case with insurance to receive transplant even if you have not failed PN. Do not be discouraged, and know your team will work with you to determine the best treatment options.

What are the contraindications to intestinal transplant?

The contraindications will ultimately be determined by your transplant team, but in most cases the following will exclude you from receiving an intestinal transplant:

• Cardiopulmonary deficiency
• Aggressive malignancy: Your transplant center may consider your cancer aggressive if it forms, grows, or spreads quickly or is unresponsive to conventional cancer treatments, such as chemotherapy and radiation.
• Some forms of autoimmune disease with poor prognosis as deemed by the transplant center.
• Acquired Immunodeficiency Syndrome (AIDS).
• Existence of life-threatening intra-abdominal infections or sepsis.
• Inadequate social or financial support.

What are the Centers for Medicare and Medicaid guidelines for intestinal transplant?

These indications are often the result of long-term TPN use because of intestinal failure caused by an underlying disease, as noted below.

What are the 3 main types of intestinal and multivisceral transplant?

1. Isolated Intestinal Transplant: This is a transplant in which only the small intestine (jejunum and ileum) is transplanted. 2. Modified Multivisceral Transplant: This is a transplant in which the stomach, pancreas, duodenum, and small intestine (jejunum and ileum) are transplanted. In some cases, the colon may be included. 3. Multivisceral Transplant: This is a transplant in which the stomach, pancreas, duodenum, small intestine (jejunum and ileum), and liver are transplanted. In some cases, the colon may be included. Please note: Multivisceral transplants can also include other organs, such as a kidney, if indicated. Please see below for a visual and more information.

Helpful Download from Transplant Unwrapped

Sign-Up or Log-In to Access: 1. The Digestive System: A brief overview of the important parts of the digestive tract.

Digestive Disease Organizations

Digestive Disease Organizations: Find a listing of numerous specific digestive disease organizations and websites to learn more about the individual causes of intestinal failure and short bowel syndrome.

Transplant Unwrapped: Learn From Others

Learn From Others: Read stories, watch interviews, and listen to audio from numerous members of the intestinal community on a variety of topics. Useful for This Section: Learn from Others- Webinars- Overview of Intestinal and Multivisceral Transplantation presented by Dr. Jafri.

Transplant Unwrapped: Support Programs

Support Programs: Visit the Transplant Unwrapped Support Programs page to get your questions answered, speak with others in similar situations, and feel well-supported during your medical journey.

Page References

References here.