 All patients will be reviewed in local haematology clinics or the TTP clinic at UCLH. Patients or their legal representatives will be informed or any update of TTP information in general or if new information becomes available about the treatmentdrug during the study or during regular outpatient consultations. Review of ongoing data will be presented at the SEE TTP study group as well as national and international meetings. The final report will be presented in peer reviewed journals. Patient will also be kept informed of any publications arising from the study and hardcopies will be made available to all patients or their next of kinlegal representative. 