Paired Donation versus Desensitization

Two of the most common reasons that patients cannot receive a kidney from a willing living donor are 1) blood group incompatibility and 2) immunity to the donor's tissues (termed "crossmatch incompatibility") 

Donor/recipient incompatibility can be overcome by one of two approaches:   1) paired donation and 2) recipient desensitization / immunomodulation. The only other alternative for recipients with incompatible donors is to receive a deceased donor kidney. The advantages of living donor transplants over deceased donor transplants are described on the Living Kidney Donation page.

Recipient desensitization involves treating the recipient with medications that reduce the immunity to HLA antigens (see Why Donors and Recipient Don't Match for an explanation of what HLA antigens are).  If a recipient has immunity to the donor's ABO blood type or the donor's HLA antigens, some treatments may signficantly reduce this immunity.  Several different types of treatment have been shown to be effective for desensitization, however, some patients cannot be desensitized by any approach. 

Most desensitization treatments usually include stronger immune suppressive therapy than usual to prevent rejection. An important disadvantage of desensitization is that it may be associated with increased risk of rejection, and also carries a higher risk of acute rejection.  In addition, acute rejection episodes in patients who have been desensitized are usually more severe and require stronger antirejection treatments.  In addition, desensitization approaches can be associated with lower survival rates for the transplant, and in some cases, lower patient survival rates.

Some desensitization approaches require a few to several months, whereas others may be substantially shorter. Waiting times for paired donations are not known, but may be a few to several months. The table below summarizes the pros and cons of these two approaches.