Crossmatch testing or crossmatching are the terms often used in connection with a kidney transplant. Still, many people wonder what is it and what is the importance of the crossmatch test for kidney transplant. This article will attempt to shed some light on this issue.
What Is Crossmatch Testing?
By blood tests and crossmatch testing (or crossmatching) we understand the comparison of blood and tissue samples acquired from both donor and recipient of a kidney transplant in order to ensure the graft survival and avoid especially the instant graft rejections and graft rejections happening within the first year after the renal transplantation.
Crossmatch test for renal transplant has come a long way from rather primitive technique of HLA tissue typing to a multi-level crossmatch testing available nowadays in clinics conducting the kidney transplant surgeries. However, the HLA tissue typing is still the first step of the whole crossmatching process. HLA stands for Human Leukocyte Antigens, which play a crucial role when it comes to kidney graft survival. There are three basic types of HLA with different variants. If HLA types of donor and recipient in kidney transplant are the same or partially the same, the operation is more likely to end with success. However, the serum crossmatch brings a definite result, since it shows whether recipient has antibodies which will attack the kidney transplant.
The Importance of Crossmatch Testing for Kidney Transplant
Despite the astonishing developments in the field of medicine, kidney transplant is still likely to fail if crossmatching shows that the donor and recipient are incompatible. HLA tissue typing insinuate the possibility of successful kidney transplant. The incompatibility in HLA may be overcome if there is no antibody reaction in the serum crossmatch. However, serum crossmatch indicating a serious conflict leads to renal transplant not being conducted since even strongest medicines suppressing the defensive reaction may not be of any help.
Therefore, even in the era of new generations of immunosuppressing medicines, doctors will always conduct a crossmatch test for kidney transplant. They do not want to risk a situation where soon after the renal transplant they will be met with acute graft rejection which leads to health- and life-threatening medical conditions.
Blood Tests and Crossmatch Test for Kidney Transplant – the Procedure
Both donor and recipient are currently checked on three levels in order to ensure that renal transplant will succeed. These levels are:
- Blood Test – a simple blood test estimates the compatibility on the level of blood groups. As we know, there are four main blood groups: 0, A, B, AB, with various compatibilities. If the blood test results are promising, doctors may pass to the second level of preparations for kidney transplant.
- Tissue Typing – tissue typing is used to establish the similarity between HLA in donor and recipient blood. If there is a significant degree of similarity, the risk of aggressive reaction in the serum crossmatching decreases.
- Serum Crossmatching – serum crossmatching is what we understand as an actual crossmatch test for kidney transplant. In it, doctors check if there are any antibodies ready to attack the donor tissue. If serum crossmatching leads to the reaction, doctors start looking for another donor of renal transplant and the whole process will start anew.
Crossmatching between the Family Members – Is It Necessary?
Unfortunately, being a family does not mean that your cross match test for renal transplant will be automatically negative (which means no reaction and the possibility of kidney transplant). HLA and antibodies are partially inherited from both parents so their children may have many different combinations of HLA and antibodies. For this reason, even between twins, doctors will conduct a serum crossmatch.