Thrombotic Microangiopathy (TMA) Associated With Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) In Adult Patients

Inclusion Criteria: * Adult patients (≥ 18 years) undergoing allogeneic HSCT in specialized centers that, as part of their usual follow-up protocol, carry out basic screening (laboratory/clinical) for TMA and in which patients consent (within the general transplant consent), to have their data used in observational studies. * Patients with ≥ 3/laboratory/clinical diagnostic markers of TMA in two consecutive assessments within 14 days, namely: 1-Elevated Schistocytes in peripheral blood; 2-LDH above the upper normal limit; 3-De novo thrombocytopenia or requirement for platelet transfusion; 4-De novo anemia or requirement for red blood cell transfusion; 5-High blood pressure (≥140/90); 6-Protein/creatinine ratio \> 1mg/mg or proteinuria ≥ 30mg/dl in a random sample). * Patients with suspected/diagnosed TMA who have signed the specific consent for the study. Exclusion Criteria: * Participation in an interventional treatment study of any therapy for TMA.