Positive Response and Increase in ADAMTS13 with Scheduled Rituximab in a Patient with Relapsing Thrombotic Thrombocytopenic Purpura.

Thrombotic thrombocytopenic purpura (TTP) is a coagulation disorder caused by a deficiency in ADAMTS13. Patients classically present with symptoms of end-organ damage as well as anemia and thrombocytopenia. Treatment is therapeutic plasma exchange (TPE) in the acute setting, with systemic immunosuppression for refractory cases. A 48-year-old female diagnosed with TTP at age 42 presented initially with altered mental status (AMS), severe anemia, and thrombocytopenia requiring intensive care unit (ICU) admission. The patient was treated acutely and discharged from the hospital. During subsequent years, multiple relapses requiring hospitalization prompted scheduled maintenance with rituximab. Since maintenance therapy, the patient remained relapse-free while ADAMTS13 levels escalated. Untreated, TTP is fatal. The treatment goal in the acute setting is the repletion of ADAMTS13 coupled with immunosuppression in refractory cases. Rituximab typically is reserved for patients who do not improve with initial TPE. Albeit unusual in TTP, rituximab maintenance in our patient induced remission. Maintenance therapy with rituximab in patients with a history of relapsing TTP can blunt or obviate the frequency of relapses and hospital admissions. More research is required to establish the effectiveness of rituximab in the chronic treatment of TTP.