Criteria 1: Must have 2 or more laboratory criteria for MAHA within 7 days or single MAHA with a haptoglobin checked within 7 days (suspicion for hemolysis) |
Red cell fragmentation and |
Slight, moderate, or marked schistocytes (>2/HPF) |
Lactate dehydrogenase and |
≧2 times the upper limit of normal |
Thrombocytopenia and |
Platelets ≦50k or ≦100k if transfused or ≧50% drop |
Anemia and |
Hemoglobin or hematocrit ≦lower limit of normal |
Timing |
All 4 laboratory values must occur concurrently within 24 hours |
Criteria 2. Does not have other obvious causes for TMA through clinical chart review |
Not isolated MAHA and |
must be persistent more than twice |
Not immune hemolysis and |
negative direct Coombs test (DAT) if checked |
Not severe coagulopathy and |
does not meet ISTH criteria for DIC |
Not disease relapse |
no documented pretransplantation disease relapse |