Incompatible Living Donor Transplant
Ideally, to be eligible for transplantation, kidney donors and recipients should have compatible blood and tissue types. Too often, however, willing live donors do not meet these medical criteria. While it remains preferable (safer, easier, and less expensive) to receive a kidney from someone who is fully immunologically compatible, recipients can be successfully transplanted from a donor with mismatched antibodies.
When antibodies are present, the blood of the recipient and donor react to each other, much like an allergic reaction. In the past, this reaction has caused the recipient's body to reject the donor organ. Today, we can successfully transplant from an incompatible donor if the recipient's blood is first "cleaned" of antibodies through a process known as plasmaphereis.
First, the amount of antibodies present must be quantified. This level helps to determine the number of treatments required. Next, the recipient's blood is separated into cells and plasma (liquid). The plasma is removed and replaced with a commercially available plasma substitute. Removing the plasma removes the antibodies. In essence, plasmapheresis is similar to dialysis; it removes antibodies just as dialysis removes waste products.
Depending on the level of antibodies present, plasmapheresis may be performed anywhere from 2-10 times. Most patients receive the treatment every other day, for up to three times a week. Once the quantity of antibodies drops to a low enough level, the recipient can undergo the transplant.
The transplant surgery for incompatible donors is essentially the same as for compatible live donors. Donor organs are obtained through a laparoscopic nephrectomy. The surgeon then places the donor kidney on one side of the recipient's front lower abdomen, using an 4-10 inch incision. The novel placement of the kidneys—versus its natural position at the back of the body—allows the surgeon to more easily connect the kidney to the bladder. To ensure an adequate blood supply, the surgeon also attaches the kidney to an artery and vein that lead to the legs. In most cases, the patient's own kidneys are not removed, thereby avoiding unnecessary additional surgery.
The transplant operation typically lasts from 2½-5 hours. Post-operative care will vary, however, from a compatible live donor procedure, as additional plasmapheresis is required.