Kidney Transplants
Pancreas Transplants
Islet Transplants
Immunosuppressant Drugs
Because of the advances in technology there are new forms of treatment for people with conditions beyond standard repair. Transplantation is an effective form of treatment for people who have organs that no longer function properly or efficiently. Common transplants for people with diabetes include kidney, pancreas, and even islet cell transplantation.
Kidney Transplant:
The kidneys are organs that filter blood and create the waste products that are excreted in the urine. Diabetes causes large amounts of glucose to be filtered through the kidneys which, over time, is very taxing on them. This can cause them to fail which requires immediate action. Failing to act while the kidneys aren’t functioning causes the system to become septic and eventually leads to death. Dialysis is another option, but it is restrictive to some lifestyles.
There are two types of kidneys that can be transplanted: kidneys from live donors or from cadavers. According to the ADA the survival rate for a person one year after receiving a kidney from a living donor is 97%, and 83% after 5 years. When receiving a kidney from a cadaver the survival rate is 93% after one year and 75% after 5 years. If someone doesn’t treat the problem of end stage renal disease (ESRD) then death is imminent.
Transplant process
There are a number of factors that go into transplants including finding the best match, being put on a waiting list, and risks of drugs necessary to survive afterwards.
Finding a match
There is a protein in the blood called the human leukocyte antigen (HLA) that is located on the surface of white blood cells. There are three types: A, B, and DR. Everyone has two sets of these antigens, one set from each parent. These antigens are tested before a transplant can take place to ensure the closest possible match. This makes is more likely to find a match from a sibling than a stranger. It is also more likely to find a match from someone with the same ethnic background.
Another factor is the fact that there are more people in need of kidney transplants then there are kidneys available. There is a waiting list that shows the types of antigens a person has and matches the first available kidney to the two people waiting the longest on the list. Each person that is a match will receive only one of the two kidneys because the body can function properly with only one healthy kidney. This process can take years so people who are waiting must receive dialysis or some other treatment until a kidney is available.
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Pancreas transplant:
The pancreas is the organ responsible for producing insulin, glucagon, and a number of digestive enzymes. The destruction of the beta cells of the pancreas is the reason for type 1 diabetes. This is the reason it can be beneficial to a person with type 1 diabetes (this surgery is not for people suffering from type 2 diabetes) to receive a pancreas transplant. The transplant can, and usually does, cure the diabetes. Unfortunately, the problem with pancreas transplants is that the person must now take immunosuppressant drugs to prevent the body from attacking the foreign organ. Even more dangerous is the fact that the same autoimmune function that destroyed the original beta cells might be triggered to do the same thing to the new beta cells. The immunosuppressant drugs also make the receiver of the new organ more susceptible to other diseases. For this reason it is said by many people who have received the transplant that it was actually better before they got it.
The transplantation of a pancreas doesn’t have the same success rate as a kidney transplant. According to the ADA 1-2 in 10 people who receive pancreatic transplants die within one year of the operation. About half of the pancreatic transplants given are rejected. For these reasons it is only recommended that this transplant takes place under severe circumstances.
Transplant process
Pancreas transplants often take place at the same time as a kidney transplant because the person will already be on immunosuppressants and they are already prepared for surgery. The pancreatic transplant takes longer and is more complicated. The same HLA matching is done for this surgery to prevent rejection.
The patient’s original pancreas is not removed during the operation. The new pancreas is usually located in the lower abdomen on the right side. It is attached to the blood vessels of the right leg because the leg already receives more than enough blood to maintain its health. There is also an attachment made to the intestines or the bladder to get rid of the waste products produced by the pancreas.
It is also common to have partial pancreas transplants performed. This is done because of a lack of organ donors which leads to a shortage in available functional pancreases. It usually comes from a living relative because they can spare part of their pancreas and still be fully functional. The partial pancreas is able to give a boon to the recipient’s pancreatic function.
Benefits
The benefits of a pancreatic transplant make it a desirable option to those who suffer from severe side effects from diabetes. They no longer need to check blood sugar, give themselves insulin shots, or turn down carbohydrate rich foods. It can also prevent the damage that occurs from diabetes from continuing.
However, there is a large probability of complications after a pancreas-only transplant so it is commonly done with patients who are receiving a kidney transplant. According to the JAMA the survival rate is better for people who are managing their kidneys than for those who receive a pancreas-only transplant.
[back to top] Islet transplant:
Islets are cluster of cells in the pancreas that are responsible for the production of insulin. They are mistakenly destroyed in people with type 1 diabetes which causes the body to produce insufficient amounts of insulin. But until the success of pancreatic transplants is improved it is common for people with type 1 diabetes to opt for islet transplants. The procedure is relatively simple and takes only about an hour.
When this procedure was in its infancy it was common to need multiple pancreases to complete it due to the number of islet necessary to complete a successful transplant. It would take hours to isolate the islets because of the small portion of the pancreas they consist of. Due to the lack of available pancreases for this procedure doctors are looking to animals for their possible availability. They are also looking for genetic engineering and islet expansion and regeneration to lend help to the progress of this procedure.
Transplant process
The preparation phase begins with the pancreas of the donor being injected with special digestive enzymes. Then the pancreas is placed in a chamber with glass beads and shaken to break it down. The pieces that are less than half a millimeter pass through a filter into a solution. A pump pushes the solution through a machine and past a group of heating coils to heat the solution. After about 30 minutes the enzymes have been heated to 37C and they dissolve the tissue around the islets. Then the solution is filtered to eliminate the enzymes and chemicals and it’s cooled to 10C to slow the chemical reaction. The cells are then collected and purified and the healthiest islets are picked and used.
Approximately 1 million islets are needed for a successful transplant into an average person’s pancreas. The surgeon uses ultrasound to run a catheter through the abdomen and into the liver where the cells are injected. Then, over time, the cells attach to blood vessels and begin producing insulin.
Benefits
According to the ADA there are some advantages to the islet cell transplantation over the transplantation of a full pancreas. First of all it is a much easier surgery than a pancreatic transplant. It is also less expensive and has been safer so far. Scientists are also working on methods of protecting the cells from the immune system which would eliminate the need for immunosuppressants.
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Immunosuppressant drugs
When a person receives an organ through a transplant they must take immunosuppressant drugs to prevent their own immune system from attacking the foreign organ. There are three types of immunosuppressant drugs that a person usually takes after a transplant including:
Primary- Cyclosporine, tacrolimus, or sirolimus
A steroid
mycophenolate mofetil, azathioprine, or rapamycin
These drugs are taken to prevent rejection. Rejection is a case where the body recognizes the organ as foreign and attacks it. This is still possible while taking immunosuppressants. Another risk of taking these drugs is the fact that while the immune system is suppressed the body is more susceptible to disease. Because of this it is recommended that while a person is using immunosuppressants they stay away from people who are sick and contagious.
This is an extreme form of treatment for someone with ESRD so it is only done in the most serious cases. A health care professional will assist in deciding if the benefits of the surgery outweigh the risks. The National Kidney Foundation is also a good resource for people considering a kidney transplant.
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