Rh blood group

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. . Rh blood group s MUHAMMAD ASIF ZEB Lecturer MLT (KMU) Master in health and professional in progress) MSc. Hematology B.Sc. MI-T Certificate in health and professtona [CHPE) ertiflcate in health research (CHR).

. . o BACKGROUND INFORM History: In 1939. a mother who had just given b needed a blood transfusion. The ABO bl been discovered almost 40 years importance of giving an ABO-compati was well established. However, althougl transfused with ABO compatible blood from o 1 experienced an adverse reaction to the t Her serum was found to contain antibc her husband's RBCs, even though they During the pregnancy. the mother had antigen on the fetal RBCs that was of pa.

. . Her immune system attacked this ant Of the fetal RBCs resulted in fetal encountered the same paternal antiy blood transfusion from her husband. The antibodies responsible led to the c group. 1.

. . o o o Landsteiner and Wiener: Rh system IDENTIFIED by Landsteiner a Immunized animals to Rhesus macaque Antibody agglutinated 100% of Rhesus a RBCs. Reactivity paralleled reactivity of sera in infant suffering from hemolytic disease..

. . Rh FACT( What does Rh refers to? Rh is the most important blood group transfusion medicine. One of the most complex of all RBC with more than 50 different Rh antigens. The genetics, nomenclature and antig unsettled. There are two genes, RHD and RHCE.

. . RHD: What does the term D-po D-negative refers to? If Protein (D antigen) is present on the cell. the blood will be termed as Depositivc If Protein (D antigen) is absent on the sur the blood will be termed as D-negative. Rh Blood Group Sys present (+) Rh positive Rh.

. . . RHCE: Four additional antigens The RhCE protein encodes the C/c extracellular loop) and the Ele antigen (i loop)..

. . o , PROTEINS WITH UNKNOWN FUNCTIONS: The RhD and RhCE proteins are bot proteins that are integral to the Unlike most cell surface molecules, the glygowsyJateg (they do not contain Olic they are closely associated with a glycoprotein called RhAG. The function of the Rh-RhAG transporting ammonium or carbon protein encodes the D antigen..

. . Rh Blood Group System • Fisher-Race (DCE terminology) — Suggested 3 sets of closely linked allel and e) — Each gene (except d, which is an amo production of an Ag — Inherited from parents in linked fashit.

. . Click to add til There are 8 gene Fisher-Race uses OCE as order the genes os (PE.

. . Rh Blood Group Syste • p. d. C. c. E. and e • is considered an @mgrph (silent alle D antigen. • The phenotype (blood type observed cit given red cells is define by the presence E and e. • C, c, E, e represent actual antibodies..

. . Variation of the Rho (D) Ant • Weak D overview • Some cells require addition of AHG (l agglutination with Anti-D • 3 mechanisms causing weak D express Genetic - inheritance of D genes whi densities of D A" on RBC membran C trans - position effect; the D gene gene, pg., Dce/dCe (C and D Ag arrai 'terjg hindrance weakening D expre I D mosaic - I or more parts Of the D result in production of Anti-D.

. . Determination of Du Statl There are instance when an accurate Rh t) determined through routine testing • I- If the new-bgcn'$cell are coated witY anti-D in utero, very few D Ag sites will with reagent anti-D. • Elution of the sensitizing Ab (removing identifying it as anti-D will verify that th are D positive • 2- Warm autoimmune hemolytic anem against thelpatient's own red cell and are Rh specific..

. . Determination of D Statu • Is essential when test donor blood samg • Blood considered Rh positive if either th positive • If any donor blood sample that types Rh either slide or rapid method must be te: indirect anti-globulin test (IDAT). • If both test results are negative, the don considered negative..

. . Detection of Rh antibodies and Antigens • Immune 'gq Abs (IgG1 and IgG3 most im • React optimally at 370C or with AHG • Order of immunogenicity: • Do not bind complement (RBC destructi xtravascular • Exposure to less than of Rh positiv stimulate Ab production in an Rh negati'.

. . Clinical Siqnificance: o o o The Rh antigens are highly immunogen antibodies should be considered as hemolytic transfusion reactions and HDh D antigen, after A and B, is the most im transfusion practice. Has been reported that 8096> of D neg single unit of D pos blood can be expec anti-D. Rh antibodies rarely, if ever, bir therefore RBC destruction is mediated macrophages in the spleen extravascul.