Hello. Thank you for taking the time to learn about kidney transplant with us today.
We hope that this video will answer a question many patients have:
how long until I get a kidney transplant? There are many factors that contribute
to how long you will wait for a kidney. These include whether you have a living
donor, how long you have been on dialysis, your blood type and your antibody levels.
It may sound complicated, but let's break it down together. Kidneys for transplant
can come from two sources. Let's talk about living donors first.
Living donation is when a kidney from a friend or a family member is put into your body.
There are lots of advantages to having a kidney transplant from a living donor.
First, the time you wait for a transplant is much shorter, and you can schedule the
surgery ahead of time. Live donor kidneys tend to last longer and they usually
work better. If you know someone who wants to learn more about being a living
donor for you, have them contact our team directly. Second, another source for
transplant is from a deceased donor. This is when a healthy kidney is donated by
someone who has died. If you don't have a living donor, you will need to join a
waiting list for a deceased donor kidney. There is a wait list for deceased donor
kidneys because there are fewer kidneys available than the number of people who
need transplants. This wait list is managed by an organization that is part
of the Government of Ontario called the Trillium Gift of Life Network, or TGLN.
TGLN makes sure that the waiting list is fair, and uses the system based on
priority and points to decide who should get a kidney first. For most patients the
most important factors that decide your wait time are your blood type, your
antibody levels and your time on dialysis. First let's talk about blood type.
There are four blood types: A, B, AB and O. You inherit your blood type from
your parents. For the purpose of the waiting list, you only get kidneys of the
same blood type as your own. The waiting time is different for different blood types.
Type A and AB patients will wait on average two to five years,
type B six to eight years and type O five to seven years.
Remember that the number of deceased donor kidneys available is much fewer than the number
of people who need transplants, and this is much more so the case for some blood
types compared to others. Let's look at another factor affecting wait time:
your antibody levels. Antibodies are a part of your immune system. Think of them as
little flags that mark any cells that are not your own
as foreign, so that they can be eaten up by your immune system.
If bacteria or viruses enter your body, having antibodies helps you fight against
getting an infection. But what happens when another person's cells enter your system?
You might get exposed to another person's cells due to having blood
transfusions, from being pregnant or from having a previous transplant. When any of
these happen, your body recognizes the foreign human cell by a protein called
human leukocyte antigen, or HLA. Every person's HLA is different. It's part of
what makes you you. Your immune system will make antibodies against the foreign
human HLA. As part of your transplant workup, you will do a blood test called
calculated panel reactive antibodies, or CPRA.
This test measures how many antibodies you have developed against other
people's HLA. It is scored as a percentage: the higher the number the
more antibodies you have against the general population of available kidneys.
If we give you one of the kidneys that you have antibodies against, there's a
very high likelihood that you would reject it immediately and it wouldn't
work for you. Let's look at an example of CPRA.
If your CPRA is 95 per cent, that means out of 100 kidneys available, you have
antibodies against 95 kidneys, but five of them will be a match for you.
Antibody levels do change over time, for example if you get a blood transfusion,
your antibody levels may increase. Once you're approved for transplant, you will
need to recheck your CPRA every three months. Your dialysis unit
will collect your blood and do this test for you. The final factor that determines
your wait time for kidney transplant is the number of days you've been on dialysis.
Like we mentioned before, TGLN uses a point system to organize the waiting list.
This is called allocation points. The higher your allocation points, the
higher you are on the waiting list. Here's how it works:
you get points for the number of days you have been on dialysis: 0.1
points for every 30 days. You also get points based on your CPRA.
We take your CPRA as a number and divide it by 100, and then multiply that by four.
Next, we can add the two sections together, the number of days you've been
on dialysis and the CPRA and you get a total number of allocation points.
Let's look at an example: David recently completed his work up, and was clear for
listing on the provincial kidney transplant waiting list. He started
dialysis two years ago. For every 30 days he spent on dialysis, he accumulates 0.1 points.
This is to make sure that the waiting list is fair for all patients,
for example if you were referred for transplant later, or your workup process
took a little bit longer, you still get credit for all the time you spent on dialysis.
In David's case, he has 2.4 points for the time he's already spent
on dialysis. David also has a CPRA of 75 per cent, which we'll divide by 100 for 0.75,
multiply that by four, and he gets another three points for CPRA.
Remember, a higher CPRA means it is harder to find a matching kidney.
That's why people with higher CPRA get more points so they can have a better
chance of finding a match. So when you put it all together, David has a total of
5.4 points. David is blood type O, so he will join
the wait list for that blood type. As David continues on dialysis, he will
gradually gain allocation points over time and move up on the list until he's
at the top of the list and is offered a matching kidney.
In summary, waiting time for a deceased donor kidney transplant is
determined by your blood type, your antibody levels, or CPRA, and your time on dialysis.
First, remember, certain blood types wait longer than others for a
kidney, depending on how many kidneys are available and how many people need them.
Second, the higher your antibody levels the harder it is to find a matching kidney.
That's why people with higher antibody levels, or higher CPRA, get more
allocation points. Finally, you get allocation points for the number of days
since you started dialysis. If you want to find out more about potential ways
that you might be able to reduce your waiting time, please check out our other
video with the link in the description below. If you have any questions about
what was talked about in this video today, don't hesitate to contact us or
check out our website. Thanks for watching!