ETIOLOGY
The disease of Thrombotic Thrombocytopenic Purpura may be precipitated by the use of estrogen or pregnancy. Pregnancy-associated TTP and the postpartum state accounts for 10-25% of TTP patients and usually presents before 24 weeks of gestation.
TTP is frequently preceded by a viral or bacterial infection. It is also associated with the human immunodeficiency virus (HIV).
There are also a vast array of causes which include cancer, collagen, and vascular disorders, as well as drug sensitivities. Non-cancer chemotherapeutic and other drugs suspect in causing TTP include: immunosuppressive agents (e.g., cyclosporine A), ticlopidine, penicillin, and rifampin. Toxins associated with TTP are E. coli 0157:H7, and spider and bee venom. Cancer chemotherapeutic agents associated with TTP include: tamoxifen, bleomycin, and mitomycin.
