Coombs tests

Coombs tests

laboratory tests that reveal certain antibody-antigen reactions; used in differentiating between various types of hemolytic anemias, for determining minor blood types, and for testing for alloimmune hemolytic disease of the newborn. Called also antiglobulin test.

direct Coombs tests
the test used to detect the presence of cell-bound antibodies that may damage erythrocytes but will not cause visible agglutination. The red cells are washed free of serum and unbound antibody, and antiglobulin (species-specific antiserum directed against antibodies) is added. Agglutination indicates the presence of antibody. Clinically its most important use is in the diagnosis of alloimmune hemolytic anemia of the newborn (Rh disease in humans) and autoimmune hemolytic anemia.
indirect Coombs tests
detects antierythrocyte antibodies in the serum. Test serum is incubated with red blood cells. The cells are then washed and mixed with antiglobulin serum. Agglutination indicates the presence of antibody in test serum. Supernatant from colostrum may be used instead of serum.
References in periodicals archive ?
Minor blood group incompatibilities should be considered in cases of hemolytic disease where Rh and ABO incompatibilities cannot be found and with positive Coombs tests (2, 5).
The minor blood groups of the mother and baby tested to investigate the etiology of hyperbilirubinemia and positive direct Coombs test were as follows: mother: C(+) c(+) E(-) e(+) Kell (-), baby: C(+) c(+) E(+) e(+) Kell(-).
These antibodies can cross the placenta and may lead to a positive indirect Coombs test in the mother.
Coombs test, indirect Coombs test in the mother, and anti-E antibody levels were positive and the diagnosis of hyperbilirubinemia caused by minor blood group incompatibility due to anti-E was confirmed.
8) reported that serious hyperbilirubinemia did not develop in a newborn whose mother had a positive indirect Coombs test in the screening performed in the 15th week of pregnancy and who had positive anti-E after delivery.
In minor blood group incompatibilities, the rate of direct Coombs test positivity is generally 33% (2, 5, 10).
Other test results (liver and renal function, serum folate and vitamin B12 levels, lactic dehydrogenase levels, C-reactive protein, serum protein electrophoresis, direct and indirect Coombs tests, and antinuclear antibody tests) were within normal limits, as were viral serologic test results (HIV, hepatitis B virus, hepatitis C virus, parvovirus B19).
It was learned that the baby had normal female karyotype in the prenatal follow-up, inversion (9) (p11;q13) which did not affect the phenotype was found, direct, indirect Coombs tests and TORCH and parvovirus serologic tests were negative and erythrocyte transfusion was performed by chordocentesis one week before the birth.
3], the blood type of the mother and the baby was found to be 0 Rh (+) and the direct coombs test was found to be negative.