Improving Thrombotic Thrombocytopenic Purpura Outcomes with a TMA Team and TTP Pathway

Background: Providing optimal care for patients with thrombotic thrombocytopenic purpura (TTP) is challenging but using a multidisciplinary team to develop a systematic process could improve TTP care by reducing morbidity and mortality. Objectives: To develop a thrombotic microangiopathy (TMA) Team and implement a TTP Pathway to improve TTP care by reducing TTP relapse or TTP-related death (TTP-RRD) at a rural, Appalachian, tertiary medical center. Methods: Prospective quality improvement project using the DMAIC (Define, Measure, Analyze, Improve, Control) methodology to develop a multi-disciplinary TMA team and a TTP Pathway. The TMA team comprised Hematology, Nephrology, Laboratory Medicine, and Pharmacy members who guided the Hematology/Oncology consult service. Pathway care included standardized plasma exchange (PEX), rituximab, caplacizumab, improved coordination between medical services, and regular outpatient biochemical TTP surveillance. TMA outcomes were determined by retrospective chart review for patients with acute TTP treated with usual care (N=16) and the TTP Pathway (N=16) between 2016 and 2023. Results and conclusions: Patients were predominantly women (63.2%), Caucasian (88.5%), located far (85%) from the medical center and low-income (46.2%) based on insurance. All patients had acquired TTP. TTP-RRD at 90 days was reduced from 56% with usual care to 6% with Pathway care (95% CI 0.23 to 0.77, P=0.022); TTP relapse alone at 90 days was reduced from 50% to 0% (95% CI 0.26 to 0.74, P= 0.0011) with TTP Pathway care. On Kaplan Meier analysis, TTP-RRD was significantly lower throughout the intervention with TTP Pathway care (P=0.018). With TTP Pathway, the duration of PEX increased (median 6 vs 12 sessions, P<0.05), as did the usage of rituximab (31.3% vs 93.8%, 95% CI -0.36 to -0.88, P=0.003) and caplacizumab (6.3% vs 62.5%, 95% CI -.027 to -0.81, P=0.001). All TTP Pathway patients underwent biochemical surveillance in remission, and 31% of patients had pre-emptive rituximab to reduce the possibility of clinical relapse. This study shows that a TMA team utilizing a protocol-based TTP Pathway can reduce TTP morbidity and improve care for this rare hematologic disease. This approach can improve the care of other multisystem hematologic diseases.