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Coombs

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dr.roh
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Topics: 159
Posts: 361

10/01/07 - 01:43 PM

Whats the difference between Indirect & direct coombs test??

Doc750
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Topics: 52
Posts: 634

10/01/07 - 02:05 PM

direct is on the blood

indirect is for the antibody

not really sure though ...

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sukhs
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Topics: 19
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10/01/07 - 02:26 PM

Direct coombs test helps in diagnosing AIHA..it test the presence of antigen directly on the surface of the RBCs.

Indirect coombs test is done for the diagnosis of the Rh incompatibilty..this tests the prescence of antigen in the plasma...

Am i correct?

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dr.roh
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Topics: 159
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10/01/07 - 04:44 PM

ok guys I am not sure....so correct me if i am wrong

**Direct coombs test...the antibodies attach to RBC's-----than it lysis the RBC's......You have hemolysis

---so direct coombs test...is positive in any disease with hemolysis????

**Indirect coombs test.....the antibodies to antigens (on RBC) is circulating in the system....Hence seen in Rh incompatibility.......So is it also seen in ABO incompatibility?????????

me007
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Topics: 72
Posts: 799

10/01/07 - 05:35 PM

dr.roh wrote:
ok guys I am not sure....so correct me if i am wrong

**Direct coombs test...the antibodies attach to RBC's-----than it lysis the RBC's......You have hemolysis

---so direct coombs test...is positive in any disease with hemolysis????

**Indirect coombs test.....the antibodies to antigens (on RBC) is circulating in the system....Hence seen in Rh incompatibility.......So is it also seen in ABO incompatibility?????????

direct Coombs positive in autoimmune (or drug-induced immune) hemolytic anemia,
IgG couts RBCs, splenic/liver macrophages phagocytose them - extravascular hemolysis

indirect Coombs - detects antibodies in the serum, used in blood transfusion screening (ABO and Rh) and prenatal screening (detect IgG antibodies in women's serum)

dr.roh
Forum Guru

Topics: 159
Posts: 361

10/01/07 - 09:13 PM

me007....thanx so much smiling face

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