Low blood count with unknown diagnosis

Hi, my mom is currently going under multiple tests to figure out what is going on. In a nutshell, they tell her she has an autoimmune disease; they've mentioned ITP, PNH, and myelodysplastic. She just finished a 2nd bone marrowbiopsy to confirm or deny. At this point they see no signs of cancer but we are still in the "unknown" area. All blood levels are very lowbut the platelets do not stay above 10,000. She has received 7 units of blood and 5 units of platelets. Anyone experience this or have further ideas. Thanks