De-novo immune-mediated thrombotic thrombocytopenic purpura following surgical and non-surgical procedures: A systematic review.

When de-novo immune-mediated thrombotic thrombocytopenic purpura (TTP) is diagnosed following an invasive procedure, clinical presentation patterns and outcomes are poorly defined. Therefore, in a systematic literature review of patients diagnosed with TTP following an invasive surgical or non-surgical procedure, we identified 19 studies reporting data on 25 patients. These data suggest that 1) TTP pathogenesis likely begins prior to the invasive procedure, 2) patients experience significant diagnostic delays, and 3) there is a high incidence of renal replacement therapy. Although invasive procedures may trigger TTP, further studies are needed to clarify the mechanisms underlying this association.

Patient-Reported Outcome Measures in Patients with Thrombotic Thrombocytopenic Purpura: A Systematic Review of the Literature.

Health-related quality of life (HRQoL) impacts of thrombotic thrombocytopenic purpura (TTP) have been captured in clinical studies using patient-reported outcome (PRO) measures (PROMs) that are validated for other diseases. However, the validity evidence to support the use of existing PROMs in patients with TTP is unknown. In a systematic review of the literature, including studies of adults and children with TTP, we assessed the validity evidence for use of PROMs in clinical research and clinical practice, characterized HRQoL, described the integration of PROMs in clinical practice and evaluated PRO scores for patients with TTP compared with reference populations. From an initial 4518 studies, we identified 14 studies using 16 PROMs to assess general HRQoL domains in patients in remission. No identified studies assessed the validity of PROMs for the context of use of TTP and no studies described PROM integration into TTP clinical practice or evaluated PROMs that were specific for patients with TTP. Moreover, PRO scores were worse in patients with TTP compared with reference populations and other chronic conditions. We conclude that, in patients with TTP, PROMs pick up on important patient experiences not captured by clinical outcomes at present. There is, therefore, a need for studies that assess the validity of existing PROMs in patients with TTP to determine if TTP-specific PROMs specific to patients with TTP should be developed.

In patients with suspected immune TTP, admission source impacts hospital length of stay and time to therapeutic plasma exchange impacts clinical outcomes.

INTRODUCTION: When immune thrombotic thrombocytopenic purpura (TTP) is suspected, outcomes are impacted by time to therapeutic plasma exchange (TPE). We evaluated the impact of time to TPE on outcomes in suspected TTP cases admitted through the Emergency Department (ED) vs. transferred from another facility (Transfer). MATERIALS AND METHODS: In a retrospective analysis of the National Inpatient Sample, we examined the association between TTP outcomes and admission source (ED vs. Transfer) for the primary outcome of time to TPE. A second stratified analyses within each analytic group examined the association of time to TPE (<1 day, 1 day, 2 days, and >2 days) and outcomes for the composite outcome of mortality, major bleeding and thrombosis. RESULTS: Of 1195 cases, 793 (66 %) were admitted through the ED and 402 (34 %) were transferred. Compared to ED cases, Transfers had a longer hospital length of stay (14.69 vs. 16.65 days, p = 0.0060). For ED cases, TPE after >2 days was associated with higher odds of the composite outcome (OR = 1.68 95 % CI: 1.11-2.54; p = 0.0150) and mortality (OR = 3.01 95 % CI: 1.38-6.57; p = 0.0056). For Transfers, TPE on day 2 was associated with higher odds of the composite outcome (OR = 3.00 95 % CI: 1.31-6.89; p = 0.0096) and mortality (OR = 4.95 95 % CI: 1.12-21.88; p = 0.0350). CONCLUSIONS: In suspected TTP admitted through the ED or transferred, there was no significant difference in time to TPE. A longer time to TPE was associated with worse outcomes. Future studies should evaluate strategies to decrease initial time to TPE.