Recruitment of patients with iTTP cohort highlighting all acute iTTP episodes occurring during the prospective study. (A) Overview of patients enrolled in remission and during an acute iTTP episode. (B) All patients suffering 1 or several acute bouts are represented over the whole study period (time axis from July 2016 to August 2018 indicated on the right side). The left side of the panel shows the 8 patients enrolled in remission who suffered from relapse(s) during follow-up (black outlined boxes with patient numbers #2, 5, 11, 15, 32, 45, 64, 84). The red and pink stars show the acute relapse(s). The right side of the panel shows the 8 patients enrolled in acute episodes, indicated by red and pink stars (patient numbers #29, 36, 44, 63, 79, 85, 86, 88). The black outline of the stars indicates initial diagnoses (patients #29, 85, 86, 88). Pink stars indicate the acute episodes of patients who received treatment prior to biobanking. No blood samples were available from them at begin of the acute bout before first TPE (refer to panel C below). Red stars mark acute bouts with complete data and biobanking. (C) Summary of all available samples of 16 patients with 22 acute iTTP episodes at various time points (days-weeks before, acute iTTP onset before first TPE, during acute iTTP after first TPE, in remission after acute iTTP).