Bowel (intestine) transplantation was first attempted during the 1960s. At that time, patients were dying of starvation after having a large portion of their bowel removed because of disease or trauma. Parenteral (intravenous) feeding was not yet available, and surgeons hoped that the transplanted bowel would function normally, allowing nutrients to be absorbed during digestion. These first intestinal transplant patients died, however, from technical complications including infection and rejection. Successful intestinal transplants were not performed until the mid-1980s when better immunosuppressive (anti-rejection) drugs became available, along with better methods to prevent infections. As a result of these improvements, more than 1000 patients have been able to stop total parenteral nutrition (TPN), resume a normal diet, and enjoy a healthy lifestyle after intestinal transplantation.
An intestine transplant is a last-resort treatment option for patients with intestinal failure who develop life-threatening complications from total parenteral nutrition (TPN). In intestinal failure, the intestines can’t digest food or absorb the fluids, electrolytes and nutrients essential for life. Patients must receive TPN, which provides liquid nutrition through a catheter or needle inserted into a vein in the arm, groin, neck or chest. Long-term TPN can result in complications including bone disorders, catheter-related infections and liver failure. Over time, TPN also can damage veins used to administer the nutrition via the catheter.
The intestine has been more difficult to transplant than other solid organs. Some of the possible reasons include:
• the large number of white cells in the bowel provide a strong stimulus for rejection
• the large number of bacteria in the gut increases the risk of infection after transplantation
Patients who receive intestinal transplants must take immunosuppressive (anti-rejection) drugs to suppress their immune systems and prevent rejection of the transplanted bowel. The drugs, taken for the life of the patient, must be sufficient to prevent rejection but supplied at the lowest possible level to minimize infection and drug toxicity.
Suitability to be considered for Intestinal Transplant:
Patients with poor intestinal function who cannot be maintained on intravenous feedings are potential candidates for transplantation. When most of the bowel has been surgically removed to treat disease, a condition called “short-gut syndrome” may result. Short-gut syndrome is the most common cause of intestinal failure, but there are diseases in which the entire intestine is present but unable to absorb fluids and nutrients.
Diseases leading to intestinal transplantation include:
- Short-gut syndrome caused by volvulus, gastroschisis, trauma, necrotizing enterocolitis, ischemia, or Crohn’s disease
- Poor absorption caused by microvillus inclusion, secretory diarrhea or autoimmune enteritis
- Poor motility caused by pseudo-obstruction, aganlionosis (Hirschprung’s disease) or visceral neuropathy
- Tumors or cancer such as desmoid tumors or familial polyposis (Gardner’s disease)
Many children and adults with diseases of the bowel do well on total parenteral nutrition (TPN) and transplantation may not be indicated for these patients. Transplantation, however, is a potentially life-saving option for patients with intestinal failure who cannot tolerate TPN or who have limited venous access.
Most intestinal grafts come from cadaver donors – people who have donated their organs at death. Occasionally, a portion of the bowel is taken from a living donor – usually a relative such as a parent or sibling.
Improved anti-rejection drugs, refined surgical procedures, better prevention of infection and a greater understanding of immunology have all contributed to successful intestinal transplants. Survival rates are now comparable to, or better than, the results of lung transplantation. Three-fourths of intestinal transplant recipients have stopped total parenteral nutrition (TPN) and resumed a normal diet. Because most of the patients in the international Intestinal Transplant Registry have been followed for a brief period time, it will take several years to obtain reliable data on long-term results.
To become the standard treatment for intestinal failure, transplantation must offer better survival, better quality of life, and lower costs than TPN. Considerable progress has been made towards these goals, but further refinements are needed before bowel transplantation becomes a routine surgical procedure.
The most common complications of intestinal transplant include infection, rejection, intestinal ischemia and leaks from the anastomoses (connection site). Because of the required immunosuppressive (anti-rejection) medications, recipients are at higher risk of infection compared to other surgery patients. There are treatment options for all of the above-mentioned complications, but in some cases may result in loss of the transplanted intestine.