Thursday, September 23, 2010

7.14 Transplant of Kidney

Physician's Notebooks 7  - Homepage - See Homepage

14. Kidney Transplant - Update 17 Feb. 2018
Match of Donor and Recipient: By ‘compatible’ is meant donor kidney that will be transplanted and will have good chance of functioning for life without being destroyed by immune rejection.
   The potential donor's and recipient's ABO and Rh blood types must be compatible. In each person, the 2 important blood antigen systems (ABO & Rh) each separately are attached to the surface of each red blood cell (RBC). In the ABO system, you are blood type A, B, AB or O. In the Rh system you are Rh+ positive or Rh- negative. (There are many subtype Rh antigens but, practically, for compatibility testing the division is Rh+ or Rh-)
Combining ABO & Rh type, here are compatibility types:

Recipient     Compatible Donors (in order of preference)
     O+          O+, O-
     O-          O-, O+
     A+          A+, O+, A-, O-
     A-          A-, O- A+, O+
     B+         B+, O+, B-, O-
     B-          B-, O-, B+, O+
    AB+        AB+, O+, A+, AB-, O-, A-
    AB-        AB-, O-, A-, AB+, O+, A+
The Rh match is less important than ABO. An ABO incompatibility of potential donor is an absolute contra to kidney transplant.
   The next important match for recipient to his donor is for individual tissue MHC classes I & II) HLA (Human Lymphocyte Antigens). There are a large number of such antigens and their individual mixes are what makes a person unique as tissue donor, and the closer the compatibility between donor and recipient, the less the chance of rejection of transplant. Family relationship is important. Identical twin is completely compatible; next comes other siblings; after that parent and first cousin.
   Differences in individual tissue (HLA) antigens are not absolutely incompatible. Transplant centers in U.S. follow a policy of mandatory sharing of 6-antigen matches for a non related kidney before accepting it as donor kidney. Today, with anti-immune medication, a non-related donor and recipient may be a successful match for transplant. This is important, because of the shortage of donor kidneys. It has allowed use of non-related cadaver (corpse) kidney and from non-related living donor.
   Pre-transplant cross-match is done before kidney transplant is undertaken. Technician incubates leucocytes (White Blood Cells) from potential donor with serum from potential recipient and with serum complement. If serum from recipient destroys the WBC of potential donor, the test is reported positive and surgeon will cancel planned transplant because immediate rejection is certain. Positive cross-match is the result of previous immunization against particular tissue antigen in proposed donor kidney. This may occur due to blood transfusion, pregnancy, or previous kidney or other organ transplant.
   The transplantation surgery must be done according to exact timing so that the donor kidney can be fresh. This is important in donor kidney survival in recipient. Post operative, expect corticosteroids and other immune system inhibitor drugs unless you are receiving a kidney from your identical twin. The dose of anti-immune medicines is maximum in the first months and gradually is tapered off but usually necessary for life. Many side effects are possible but they pale when considered against the side effect of no transplant and your kidney terminally failing.

Considerations of a donor: A donor should realize that in donating a kidney, the donor ups risk of shortening life or of unpleasant bad health such as hypertension, coronary artery disease, or years in renal failure. Kidney function cells are not replaceable and their numbers decrease with wear and tear of aging.
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7.15 Prostate Cancer & Other

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