An autoagglutination is the clumping together of an individual's red blood cells by his or her own serum due to being coated on the surface with antibodies.
formalization
Autoagglutination should also be distinguished from "Rouleaux formation" wherein normal blood tends to form stacks on keeping, which disperses on dilution with normal saline.
Instead of using antisera for blood grouping , pooled known RBCs are used. the process is serum typing.so serum of patient whose Rbcs are auto aggluting is used.