Features and Relapse/Refractory Disease Risk Factors of Patients with Acquired Thrombotic Thrombocytopenic Purpura in the Western Mediterranean Region of Turkey

Abstract

The importance of parameters that predict and prevent relapse has increased in thrombotic thrombocytopenic purpura (TTP), where response and overall survival rates exceed 90% with current approaches. In this respect, we examined the clinical presentations, laboratory findings, treatments, treatment responses, states of relapsed/refractory disease and overall survival rates of immune-mediated TTP (iTTP) patients in the western Mediterranean region. 35 adult patients who were diagnosed with iTTP in the last 10 years were included in the study. The median follow-up period of the patients was 46 (2-118) months, and 32 patients (91.4%) survived. While clinical remission was achieved in 20 (57.1%) patients in the first-line treatment group, clinical remission was achieved in 20 of 21 patients who received second-line treatment due to relapsed/refractory disease. Rituximab, which was used as the first-line treatment in only 4 patients, was given to 14 patients as the second-line treatment. Due to relapse, 5 patients received third-line treatment, and 2 patients received fourth-line treatment. There was no relationship between age, sex, clinical presentation, laboratory findings, the number of plasmapheresis treatments, and either ADAMTS13 inhibitor levels or relapsed/refractory disease. Although several parameters, such as age, low ADAMTS13 activation, and high lactate dehydrogenase, have been reported to be prognostic in the past, we believe that these findings should be reconsidered with current treatment approaches that provide a greater than 90% response and overall survival. In our study, we did not detect either a predictive factor for relapsed/refractory disease or a clinical indicator influenced by ADAMTS13 inhibitor levels.