Why Would A Person Receive Multiple Blood Transfusions? There Was

Why would a person receive multiple blood transfusions? There was no Trauma, family understood it to be 'diluting/replacing her blood because she had something in the blood system attacking her'. 40 yr old female with history of seizures in childhood, blind in one eye, apx.25% vison in the second (not result of injury). family reports 7 Transfusions given 1 week ago. Woman had been on blood thinners, they were stopped when she left hospital..week ago. Blood work was taken today and she was re-admitted and getting blood thinners again. just struggling to understand on the most basic level. Any help appreciated..she is out of state.