BLOOD TYPES; TRANSFUSION; TISSUEAND ORGAN TRANSPLANTATION

DR. MUHAMMAD UMAIR

TRANSFUSION REACTIONS RESULTINGFROM MISMATCHED BLOOD TYPES

donor blood RBCs are agglutinated.

Why not Recipient’s?Because plasma portion of the

donor blood immediately becomes diluted by all the plasma of the recipient,

Decreasing titer of the infused agglutinins

TRANSFUSION REACTIONS

Antigen- Antibodies Reaction occurs

HEMOLYSIS Hb is released and converted by the phagocytes into bilirubin

Then excreted in the bile by the liver,

Jaundice ( Hyperbilirubinemia ) if liver function is normal,

Jaundice doesn’t appear until more than 400 milliliters of blood is hemolyzed in less than a day.

ACUTE KIDNEY SHUTDOWN AFTER TRANSFUSION REACTIONS.

Three causes:1. Renal vasoconstriction due to

Toxic substances2. Circulatory shock due to loss of

circulating RBCs3. Renal tubular blockage due to

tubular hemoglobin precipitates Management : Artificial kidney

transplant Fate : Death within a week to 12

days,

TRANSPLANTATION OF TISSUES AND ORGANS

Additional complement of antigens on tissue cells So foreign cells transplanted anywhere into the

body of a recipient can produce immune reactions.

GRAFTING TYPES:A. Autografts, from one part of the same animal to

another partB. Isograft, from one identical twin to another,C. Allograft, from one human being to another or from

any animal to another animal of the same species, e.g

D. Xenograft. from a lower animal to a human being or from an animal of one species to one of another species,

ATTEMPTS TO OVERCOME IMMUNEREACTIONS IN TRANSPLANTED TISSUE Tissue Typing—The HLA Complex of

Antigens HLA antigens. Six are present on cell

membranes as well as lymphocyte membranes of every person.

Antigens’ matching Best possible matching Best results in siblings and between

parents and children . transplants between identical twins are

almost never rejected because match in identical twins is exactly same.

THANKS

PREVENTION OF GRAFT REJECTION BY SUPPRESSINGTHE IMMUNE SYSTEM

In the normal person, even with the best possible tissue typing, allografts seldom resist rejection for more than a few days or weeks.

T cells Suppression is required Glucocorticoid hormones Various drugs (azathioprine) that have a toxic effect on the lymphoid system.

Cyclosporine