My Mother Was Just Hospitalized With An H&H And 7.1

My mother was just hospitalized with an H&H and 7.1 and 20.6. Her WBC's were 216,000. She received 2 units of packed RBC's and was sent home the next day. Whe was diagnosed with CLL 7 or 8 years ago. She had a hematology consult and they want to start her on Leukeran at a very small dose. Her repeat H&H after the transfusion was 10.9 and 32.4. I told the hematologist that 2 units should bring her count up to 9.1 and 26.6 and he said he doesn't believe in the expectation. Her creatinine was 1.8 and GFR 26. When do patient's not make enough erythropoietin? How do I know for sure that now is the time to start treating her?.