After Your Islet Transplant
Immediately after transplant you will continue to take some insulin, although usually this is at much lower doses than before transplant. Your insulin requirements will change week to week, and the transplant team will help you to make adjustments, so you will need to monitor your blood glucose and insulin use very carefully.
It is important to remember that the islets will take several weeks to settle into their new home in your liver. We call this process engraftment. During this period we will ask you to keep tour blood glucose levels within quite a tight range so the islets are not overworked. This is similar to when you plant a crop. Not every seed that you put in the ground will grow into a plant. However, if you prepare your soil and feed and water the seeds, you increase your chance for a good harvest.
This is the same with an islet transplant: if you take good care in this initial time period, you have a better chance of good islet function. This includes watching your diet and living a healthy balanced lifestyle.
What about the immune system?
Following discharge you must help with the care of the islets. You will require immunosuppressive drugs for as long as the islets are functioning. If you fail to take the drugs your body will destroy the islets by a process called rejection.
What is rejection?
Rejection is the process when transplanted cells are destroyed by the body's immune system. Normally the immune system is there as a natural defense against bacteria and viruses to prevent infections. Your immune system will identify that your transplanted islet tissue is "foreign" to you and will then activate processes to attack and destroy them.
It is not easy to tell if you are rejecting your new islet tissue. If your islets are rejected they will no longer produce insulin and your blood sugars will run high. Unfortunately, by the time this happens it will probably be too late to reverse the rejection and the damage may be permanent.
It is therefore very important to prevent rejection by maintaining the levels of anti-rejection (immunosuppression) drugs in their target range.
How do we prevent your body from rejecting the islet cells?
We use medications to dampen down the activity of the immune system. We suppress your immune system just enough so that you do not reject your islet tissue, but still leave it active enough to deal with common infections.
These medications are called immunosuppressants. The drugs we use most commonly for maintenance are tacrolimus (Prograf®) and mycophenolate mofetil (CellCept®). Around the time of transplant we use other drugs, including daclizumab (Zenapax®), Thymoglobulin® and Etanercept®. These drugs work together to attack the immune system from several directions to stop it from being activated. Generally you will take two immunosuppressant drugs to prevent rejection. Your nurse coordinator and a transplant physician will explain these medications to you. Other drugs or antibodies may be used to prevent rejection depending on results of future studies.
We must monitor blood levels of your immunosuppressive drugs closely to make sure you do not have too little of these drugs in your system (so that you do not reject your islet tissue) or have too much which could cause side effects. Once you are at a stable level the frequency of your monitoring will be decreased.
How does the immune system work?
In very simple terms, white blood cells function to identify and neutralize foreign cells and particles. Some white blood cells mainly function to identify invading cells and call for reinforcements; these reinforcements are the killer cells which destroy the foreign cells. After any encounter like this, the immune system remembers the identity of these invaders so it can deal with future attacks much more quickly.
This provides us with immunity. As a general example, when you have a flu shot, a live (but weak) influenza (flu) vaccine is injected into the body and the immune system will fight it off and therefore recognize it more quickly in the future. The immune system protects us from viruses, bacteria, fungus and cancer.
How to manage your medications
Common side effects of all immunosuppressant medications
You are not expected to get all the side effects that are listed for each drug. In fact, you may not experience any side effects at all. However, it is important that you know what to expect should they occur and how to manage them. In addition, it is important to note that you may develop some side effects that are not yet recognized. We learn new information with each transplant and from each patient.
General decreased ability to fight infection
Tacrolimus (Prograf®) — Tacrolimus acts directly on white blood cells to reduce their ability to identify foreign cells.
How to take
Sirolimus (Rapamycin®, Rapamune®) — Sirolimus is a relatively new medication that is used to prevent rejection. It has been reported to have anti-tumor activity. It decreases the ability of your body to identify invading cells .
How to take
Daclizumab (Zenapax®) — Daclizumab is a genetically engineered antibody that inactivates the building blocks of the immune system. This protection for your islet tissue lasts approximately four months, decreasing the risk of acute rejection at the most vulnerable time period following the transplant procedure.
How to take
Daclizumab is given intravenously in 50 to 100 ml of normal saline over fifteen to thirty minutes, once before transplant and once four to five days after transplant. This is administered in the Medical Outpatient Unit of the University Hospital. Pulse and blood pressure are taken pre-infusion, post-infusion and fifteen minutes post-infusion.
There are no known side effects directly linked to daclizumab, but there may be side effects due to the administration of a foreign protein including itching, rash, fevers, shortness of breath, back or flank pain or low blood pressure.
Three serious side effects have occurred with patients taking daclizumab - shortness of breath, low oxygen levels in the blood and renal vein thrombosis (clotting) - however, these could also be due to many other underlying factors and therefore are not proven to be caused by Zenapax® itself.
At our centre, most patients have not experienced any major side effects from this drug. However, some have experienced fatigue after the daclizumab infusion.
As we gather new information, and new medications become available, there may be other immunosuppressant medications that will be prescribed to you. Other medications that have been used for some patients include Thymoglobulin® and CellCept® (mycophenolate mofetil).
Anti-thymocyte Globulin (Rabbit) (Thymoglobulin®) Anti-thymocyte Globulin (ATG) is a medication which modifies your immune system, so your body will accept the islet tissue. It is a mixture of antibodies that recognizes key receptors on T-cells (part of the immune system, which are responsible for attacking and rejecting foreign substances within the body) ATG destroys these T-cells and decreases the risk of rejection. The drug remains active in your system for days to weeks following treatment. This medication has been used extensively in kidney, liver, heart, lung, bowel and bone marrow transplantation.
How to take
ATG is given intravenously in the hospital at the time of transplant, as a continuous infusion.
As with any medication, use of ATG can result in serious infusion-related reactions which could be life threatening. You will be given medications prior to infusion to decrease the risk of the infusion-related reaction.
Common side effects associated with ATG include fever and chills. To a lesser extent, people have also experienced diarrhea, headache, aches/pains, nausea, swelling of extremities, shortness of breath, weakness, increased pulse and increased blood pressure.
Mycophenolate Mofetil (CellCept®) —CellCept® is a medication used to prevent your body from rejecting your transplanted islets. It does this by lowering the activity of the immune system.
How to take
Call your doctor right away if you notice any of these side effects:
Infection is a common complication after transplantation. As you have already learned, your suppressed immune system has less ability to fight the organisms in your body that cause infection. Your immune system attacks any organisms that are identified as not belonging in the body. When the immune system is unable to control an organism, infection occurs. We use medications to prevent infection (prophylaxis) and to treat infections (therapy). You will know when you have an infection. When the body is fighting an infection, there is cell damage and there are chemicals released that cause symptoms. These symptoms are signs that your immune system is fighting an organism, so it is important to know what to look for.
Increased temperature (higher than 38.5C), chills and/or shivering, pain, swelling, redness and heat in any area of the body. Feeling very tired, achy or weak. Vomiting or diarrhea. Frequent, painful urination or change in color, amount or odor of your urine. Cold symptoms, green sputum (phlegm). Sores on your lips, mouth or face.
Bacteria, viruses and other organisms are everywhere: on your skin, on surfaces you touch, in the air you breathe and in the food you eat. They also live in our bodies. However, only a small number of organisms cause illness. Organisms can enter your body from an injury to your skin or through body cavities such as your nose or mouth that are exposed to the environment. That is why good hygiene is an important way to prevent infection.
Hand washing is the most effective way of reducing your risk of infection. Avoiding contact with those who are ill is another common sense way to stay healthy. Ensuring your body is healthy by eating a good diet, getting adequate rest, exercising regularly and having regular dental care also help prevent infection.
Even with our best efforts to stay healthy, we still get infections. Sometimes our immune systems need help in keeping infection under control. The following is a description of the types of organisms that cause infection. You will also learn about the most common infections that occur after a transplant. Finally, we will tell you about the drugs that you might need to manage infection.
Organisms that Cause Infection
Epstein-Barr Virus (EBV)
Medications for Preventing and Treating Infection
Co-trimoxazole (Septra®, Bactrim®) Co-trimoxazole is part of the family of medications commonly called "sulfa drugs". It is used to prevent pneumonia from Pneumocystis carinii. You will take the medication for six months after your transplant.
How to take
Pentamidine® — This medication is used as an alternative to co-trimoxazole when it is not suitable (example: allergy). It is used to prevent pneumonia from Pneumocystis carinii.
How to take
Ganciclovir (Cytovene®) — This medication is taken by mouth and is used to prevent CMV and EBV infections from your donor organ. In the event you develop infection, larger doses given intravenously will be used to control the infection. You may not require this medication depending on whether or not you or your donor have been previously exposed to these viruses, and the type of immunosuppressant medication you are taking.
How to take
Your Post Transplant Schedule
The frequency of blood testing will decrease over time as your islet tissue begins to work and your drug levels are stabilized. Eventually, you can have your bloodwork done in a lab closer to your home.
For the first blood work of every month, you will have your lipids tested. You will not be able to eat or drink anything other than water for twelve hours before the test. No alcohol for thirty-six hours before the blood test and no caffeine for 12 hours before the test.
Keep track of your daily blood sugars and bring your records to the appointments.
An example of follow-up studies and time required
Here is an example of the post transplant yearly schedule:
PATIENT POST OP YEARLY TESTING / APPOINTMENTS
ADDITIONAL TESTS / APPOINTMENTS: Please book these yourself.
Fundal Photography, Ophthalmologist (Eye Doctor), Family Physician, Dentist, E.C.G. (Electrocardiogram).
See appendix_b for an example of our current post transplant blood work scheduling. Of course, this is subject to changes as we gather new information and make changes in our program.
For more information contact the Clinical Islet Transplant Program:
Clinical Islet Transplant Program
Copyright 2009 Clinical Islet Transplant Program