Role of methylene blue-treated or fresh-frozen plasma in the response to plasma exchange in patients with thrombotic thrombocytopenic purpura

Twenty patients with thrombotic thrombocytopenic purpura (TTP) underwent plasma exchange using either standard fresh-frozen plasma (Group A, n = 13) or methylene blue-treated plasma (Group B, n = 7). Both groups presented similar characteristics except that bilirubin values were higher in Group A (P < 0.05). The complete remission rate was higher in Group A than B (69% versus 57%). The mean number of procedures was higher in Group B (21 <plus/minus> 7 versus 11 +/- 3, P < 0.01) and the mean duration of hospitalization was also longer (37 <plus/minus> 12 d versus 22 +/- 11 d; P < 0.01). Our study shows that the use of methylene blue-treated fresh-frozen plasma to treat TTP is associated with a higher number of plasma exchanges and greater transfusion requirements without improving clinical results.