Methylene blue-treated plasma, versus quarantine fresh frozen plasma, for acute thrombotic thrombocytopenic purpura treatment: Comparison between centres and critical review on longitudinal data

Abstract

Introduction: Therapeutic plasma exchange (TPE) is the first-line treatment for acute thrombotic thrombocytopenic purpura (TTP). Methylene blue-plasma (MBP) has been used for over 20 years, but its efficacy in this setting remains controversial.

Patients and methods: this is a comparative analysis of the experience of two Centres, with different plasma products, to evaluate their efficacy in TTP. One centre used quarantine plasma (QP), and MBP the other. We performed a retrospective longitudinal study, analysing the clinical files of TTP patients of a 13-year data evaluation period. Duration of treatment and transfusion parameters, medical record, laboratory testing, concomitant medication, and survival rate, were assessed for every episode.

Results: During the study period, 12 (55.5 %) and 10 (45.5 %) new cases were treated with QP and MBP, respectively. There were no significant differences between the mean numbers of TPE processes, days elapsed from diagnosis to TPE, and plasma volume transfused. The QP TPE episodes of treatment were significantly associated with an increased time to recovery compared with MBP episodes of treatment (p = 0.004).

Conclusion: MBP was as effective as QP in the treatment of TTP patients. Since recovery was more favourable when MBP was used, we consider MBP remains a suitable alternative to treat TTP patients.

Keywords: Methylene blue-photoinactivated plasma; Pathogen reduction; Quarantine plasma; Therapeutic plasma exchange; Thrombotic thrombocytopenic purpura.