Weighing the Options for Incompatible Living Donor Pairs

by Steven Katznelson, M.D., medical director, Kidney & Pancreas Transplant Program, and Laura Miyashita

Not long ago, individuals awaiting a kidney transplant who had an incompatible living donor would have to wait idly until a deceased donor kidney became available. Now, with new research and technology, incompatible living donors and recipients have more possibilities. "From immunoadsorption to plasmapheresis to kidney paired donation, there are more options than ever," says Steven Katznelson, M.D., medical director of California Pacific's Kidney & Pancreas Transplant Program. The question is how do donor and recipient pairs determine the best, most worthwhile option?

"Individuals often evaluate their options after blood tests show ABO type incompatibility or positive crossmatch testing," says Katznelson. A positive crossmatch indicates rapid rejection could occur and that a transplant is risky. In comparison, negative crossmatch results are desirable, as they indicate the "foreign" donor tissue lacks antibodies that could damage a donor kidney following transplant.

New Techniques for Incompatibility

There has been some success using new techniques when a positive crossmatch or ABO incompatible transplant (ABOIT) occur, says Katznelson. These include:

• Immunoadsorption - A technique that helps remove potentially harmful blood group antibodies prior to transplant. Immunoadsorption, in combination with new anti-rejection medication combinations, has allowed for successful kidney transplantation in some studies, mostly reported in Japan.


• Desensitization - A process that removes antibodies or makes them less harmful, thus increasing the chance of a successful transplant. Desensitization may be an option for living donor pairs with incompatibility due to a positive crossmatch.

Typically, desensitization uses one or two technologies: plasmapharesis or intravenous immune globulin (IVIG). Plasmapharesis removes harmful antibodies using a method similar to dialysis. IVIG is a medication infused before and often after transplant to make antibodies less harmful. Other new medications have also been used with some success.

ABO Compatibility

Recipient	Donor
A	O, A
B	O, B
AB	O, A, B, AB
O	O

"While ABOIT and desensitization have reasonable track records, they are both associated with significant concerns," says Katznelson. "In both cases the harmful antibodies could return weeks, months or years after treatment, causing late rejection of the transplant."

KPD Offers Excellent Success

An increasingly common option for incompatible pairs is kidney paired donation (KPD). This type of transplant enables donor-recipient pairs to "swap" kidneys so that each recipient ultimately gets a compatible living donor kidney. "Kidney paired donation has yielded greater long-term success rates than either ABOIT or desensitization," explains Katznelson. Additionally, because most patients receiving KPD transplants need no additional therapies (unlike ABOIT and desensitization), the process is both easier and less expensive for the recipient.

"Our Kidney Team stresses the importance of finding an 'antibody-free' solution for incompatible donor-recipient pairs," says Katznelson. Accordingly, California Pacific has a comprehensive kidney paired donation program and software that helps identify compatible donor-recipient pairs. Katznelson adds, "Only if we do not find a match using KPD do we look to other options."

article published in Fall / Winter 2011Kidney Review newsletter