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Mothers who are negative for the Kell 1 antigen develop antibodies after being exposed to red blood cells that are positive for Kell 1.Over half of the cases of hemolytic disease of the newborn owing the anti-Kell antibodies are caused by multiple blood transfusions, with the remainder due to a previous pregnancy with a Kell 1 positive baby.
Up to 30ml of foetal-maternal transfusion may take place with no significant signs or symptoms seen in either mother or foetus. [3] Loss in excess of this may result in significant morbidity and mortality to the fetus. Fetal-maternal haemorrhage is one cause of intrauterine death (IUD).
If a person without a Kidd blood antigen (for example a Jka-Jkb+ patient) receives a Kidd antigen (Jka-antigen for example) in a red blood cell transfusion and forms an alloantibody (anti-Jka); upon subsequent transfusion with Jka-antigen positive red blood cells, the patient may have a delayed hemolytic transfusion reaction as their anti-Jka antibody hemolyzes the transfused Jka-antigen ...
Blood compatibility testing is routinely performed before a blood transfusion.The full compatibility testing process involves ABO and RhD (Rh factor) typing; screening for antibodies against other blood group systems; and crossmatching, which involves testing the recipient's blood plasma against the donor's red blood cells as a final check for incompatibility.
The red blood cells are removed by macrophages from the blood circulation into liver and spleen to be destroyed, which leads to extravascular haemolysis. This process usually mediated by anti-Rh and anti-Kidd antibodies. However, this type of transfusion reaction is less severe when compared to acute haemolytic transfusion reaction. [36]
Intraperitoneal transfusion—blood transfused into fetal abdomen; Intravascular transfusion—blood transfused into fetal umbilical vein—This is the method of choice since the late 1980s, and more effective than intraperitoneal transfusion. A sample of fetal blood can be taken from the umbilical vein prior to the transfusion.
The anti-RhE antibody can be naturally occurring, or arise following immune sensitization after a blood transfusion or pregnancy. The anti-RhE antibody is quite common especially in the Rh genotype CDe/CDe; it usually only causes a mild hemolytic disease, but can cause a severe condition in the newborn.
Valenti hypothesized in 1972 that the procedure he used to obtain fetal tissue could be used to obtain fetal blood, and in 1973, he was able to sample fetal vessels; fetoscopy was used and refined between 1974 and 1983 as a prenatal test to determine fetal status as well as obtain fetal blood and perform transfusions in some cases. [7]