Matching?

[CA_Coast]

Hello. My cousin is so very generously giving me a kidney due to my PKD She has been approved as a donor for me, but I read in other posts comments about 3/6 or 4/6 matches. Can someone clarify what this means? Thank you.

[Sparkles614]

Hi CA_Coast, What others are referring to when they are discussing 3/6 or 4/6 has to do with the number of antigens matched. In a nutshell, antigens have to do with how well the donor and recipient are biologically compatible to help prevent rejection of the transplanted organ. So in the scenario of 3/6 the the 6 represents that total number of antigens. The 3 shows the number of antigens that are compatible between the two individuals. The best match is 6/6 and is extremely rare. My first transplant was a 2/6 and I had 10 great years. Oftentimes, doctors don’t like to share this information because there are many things taken into consideration when finding a match. The last thing they want is for the patient to dwell on I “only had a 2/6, so it probably won’t last that long.” There is a lot of good information on the internet to help you understand the process better. Hopefully, the information I’ve shared gives you an idea where to begin. Best wishes to you on your transplant journey.

[drlew]

Hello CA coast! I have a lot of experience as a physician with living donation and the fact that you are receiving a kidney from a living donor is great. The degree of matching doesn't affect longevity or risk of rejection unless you get a 6/6 match (which is the best). Sparkles614 is correct. All of our tissues have markers/antigens on them called HLA antigens. You get half from you mom and half from dad. These antigens distinguish you from someone else and yes they will cause an immune response (like like a virus or bacteria) if your immune system is not suppressed. HLA antigens are divided up by Mendelian genetics, so you will share half with mom and half with dad. If you have brothers and sisters, there is a 25% chance a sibling will be no match (0/6) a 25% chance he/she will be a perfect match (6/6) and 50% chance he/she will be half match (3/6). Predictions from relatives further out are harder, but the main thing is that you have a living donor which is wonderful. Matching comes into consideration for people that already have a lot of antibodies against other peoples antigens (like being vaccinated). These antibodies develop after blood transfusions and pregnancies.

[CA_Coast]

Thank you both. I thought that was what it referred to, but I’m pretty sure it was mentioned at my last evaluation that my cousin was 0/6. Wish it was better but will hope for the best.

[Gardner-NY in reply to CA_Coast]

Hi CA_Coast, my husband and his older brother both have genetic PKD from their mom. His older brother got his kidney from his wife and it worked well for 17 years, so she is not blood related and things worked well for him. My husband received a deceased donation 8 months ago and so far the filtering of blood is working well, but we are still working on his very low "iron stores"/no energy for 6 months. So your receiving a live donation is a great thing! I am happy for you.

[drlew]

CA-coast let me reassure you the biggest difference in longevity is living donor vs deceased donor. I've been a kidney surgeon specializing in living donation for years. It's wonderful you have a living donor - you'll do well.

[DexterLab]

I had a living donor transplant 5 months ago. They had a new matching technique. As I understand it, the white blood cells are extracted from my blood sample then mixed in with his blood sample. If mayhem ensues, then we are not a match. Otherwise, we are a enough of a match for the antirejection drugs to handle. So far, so good!

[CA_Coast in reply to DexterLab]

Congratulations! I think that is the “crossmatch” they do initially and again just before the transplant.

[DexterLab]

That test was done twice, like you said. Never heard a x/6 number for our match. They did run some HLA titers a month ago and all is good. I have done super, so far.

[ArsenalFan]

My donor was my wife and she was a 2/6. Six years in and the kidney is wonderful.

[CA_Coast in reply to ArsenalFan]

Good to hear.

[FrankF]

In 1971, my second transplant was a 1/6 cadaver match. With just prednisone and Imuran, it lasted for 18 years. I'm sure if I had the current drugs it would have lasted a lot longer. You will do well. I currently have a 6/6 from my sister and in Jan of 2020 it will be 30 years.

[CA_Coast in reply to FrankF]

Congratulations on your first and upcoming one. And thank you for the reassurance. I know they wouldn’t go forward if they didn’t think it would work.