Immunosuppression

Immunosuppression is the name of a group of medications given to reduce the strength of the immune system to prevent rejection of the kidney. These do have side effects both generally by making the immune system weaker as well as specific side effects of individual drugs. We usually give a combination of drugs to give a good effect while minimising the risk of side effects from each individual drug. The exact combination may depend on the tissue typing mismatch between donor and recipient.

Common drugs used

Tacrolimus

Tacrolimus reduces the ability of the immune system to recognise and attack new foreign tissues, including transplants. It is particularly effective for preventing transplant rejection as it works on the part of the immune system that causes rejection but does not interfere so much with existing immunity to bacteria and viruses.

The doses needed vary a lot between people, and even the same person may need different doses at different times. We check the dose is correct by measuring levels of tacrolimus in the bloodstream using a blood test in the ward and clinic. Getting the level right is important as a level that is too low can lead to rejection and a level that is too high can damage the kidney and cause other side effects. This test ideally needs to be taken 12 hours after the last dose, so you need to not take your morning dose of tacrolimus on clinic days until after the blood test has been taken.

We mostly use Prograf, which is a form of tacrolimus taken twice per day, but some patients are converted to once per day versions called Advagraf or Envarsus. It is very important not to switch between different forms of tacrolimus - you should always get the same version; if we need to change the version you are taking, we will monitor your blood levels closely during the changeover period.

Mycophenolate mofetil (MMF) and Myfortic

MMF and Myfortic are similar drugs that work in similar ways to reduce the risk of rejection when used with tacrolimus. MMF is our standard drug but some patients get diarrhoea with it - if that happens we can sometimes reduce the severity of the diarrhoea by reducing the dose or changing to Myfortic.

Both MMF and Myfortic can cause serious defects in unborn babies. It is extremely important not to get pregnant or conceive a baby while on MMF or Myfortic.

Prednisolone

Prednisolone is a steroid, which helps to reduce the risk of rejection when used with tacrolimus and MMF. It is not an anabolic steroid, as infamously abused by some athletes, but a different type of steroid. It can cause side effects such as weight gain, poor sleep and weakening of the bones, as well as making blood sugar levels harder to control in diabetic patients, so we aim to reduce the prednisolone dose as quickly as we can. However, steroids cannot be stopped suddenly so you must make sure you do not run out, and if you get admitted to another hospital it is important you tell them you are on steroids.

Co-trimoxazole

Co-trimoxazole is an antibiotic we will give you for the first six months after the transplant. It is used to prevent a rare but very serious lung infection called Pneumocystis jiroveci pneumonia, also known as Pneumocystis carinii pneumonia (PCP).

Valganciclovir

Valganciclovir is an anti-viral drug given to some patients to prevent infection with a virus called CMV. This is a very common virus and is very mild in people with normal immune systems - in fact most of us have had the infection without noticing. Once infected, the virus never leaves the body and can be passed on with the kidney. Patients who have previously had CMV infection will have antibodies to it, but those who have not had CMV infection will get valganciclovir to stop them catching it from the kidney donor. We also give valganciclovir to some patients who have CMV antibodies but have needed additional immunosuppression.

The dose of valganciclovir depends on your kidney function, and will be adjusted as the kidney recovers.

Basiliximab

Basiliximab (Simulect) is an antibody infusion given just before the transplant, with a second dose four days after the transplant. It is used for most first transplants.

ATG

ATG is a powerful antibody infusion that gets rid of the type of white blood cell that causes rejection. It can cause symptoms similar to having the flu, and there is a higher than normal risk of infections after being treated with it. We use it for a small number patients at high risk of rejection or an even smaller number of patients with severe rejection. We give additional medications before each dose to reduce the side effects.

Less common drugs used

Belatacept

This is given by intravenous injection approximately once per month. We use this only very rarely in patients who cannot have tacrolimus.

Azathioprine

This is a tablet used instead of MMF or Myfortic, and has a similar effect but works in a different way. It was used very commonly in the past, and we still use it occasionally in patients who cannot have MMF or Myfortic. It is also used commonly in patients who had their transplant a long time ago and have been on azathioprine ever since then.

Ciclosporin

Ciclosporin, also called cyclosporine, works in a similar way to tacrolimus. We don't tend to use it for new transplants, but there are many patients still getting follow-up for old transplants who are still taking it. Like tacrolimus, it needs to be monitored using blood tests and it if you are on it, you need to remember not to take the morning dose on clinic days until after the blood test is taken.

Sirolimus

Sirolimus is used very rarely in patients who cannot have tacrolimus or ciclosporin due to kidney damage. It also needs to be monitored with blood tests in the clinic.

Sirolimus can slow wound healing, so if you need an operation while on sirolimus then make sure that your surgeon liaises with the transplant or nephrology service before you have your operation as we will need to change your medication around two weeks before the operation and then change you back to sirolimus several weeks after the operation.