Thrombotic thrombocytopenic purpura (TTP or Moschcowitz syndrome) is a rare disorder of the blood-coagulation system, causing extensive microscopic clots to form in the small blood vessels throughout the body. These small blood clots, called thrombi, can damage many organs including the kidneys, heart and brain. In the era before effective treatment with plasma exchange, the fatality rate was about 90%. With plasma exchange, this has dropped to 10 t six months. Immunosuppressants, such as glucocorticoids, rituximab, cyclophosphamide, vincristine, or cyclosporine, may also be used if a relapse or recurrence follows plasma exchange.