Factors associated with treatment outcome, and long-term prognosis of patients with ulcerative colitis undergoing selective depletion of myeloid lineage leucocytes: a prospective multicenter study.

Background: Patients with ulcerative colitis (UC) have elevated/activated myeloid lineage leucocytes and may respond favorably to adsorptive granulocyte/monocyte apheresis (GMA). However, there are patients who respond well to GMA, and patients who do not benefit. Therefore, predictive factors of GMA efficacy need to be defined.

Methods: In a prospective multicenter setting, 200 UC patients at 32 institutes received one GMA session per week over 10 weeks. Patients who achieved remission were followed for 12 months. The Clinical Activity Index (CAI) ≤3 meant remission, and response meant CAI decreased by ≥3. Quality of life was evaluated by the Inflammatory Bowel Disease Questionnaire (IBDQ).

Results: After final GMA, remission, response and no response rates were 67.0%, 15.0% and 18%, respectively. The remission group had a significant decrease in myeloid leucocytes and platelets. Corticosteroid dose decreased (P < 0.001); 49 of 97 patients on corticosteroids became steroid-free. Baseline CAI was lower in the remission group versus non-remission (P < 0.01), whereas IBDQ was higher in the remission group versus non-remission (P < 0.05). After 12 months, 52 of 134 patients had maintained remission. Disease duration was longer in the relapsed group versus maintained remission group (P = 0.041). Male gender, first UC episode and corticosteroid responder were significant factors for maintaining remission, whereas corticosteroid dependent UC was associating with relapse.

Discussion: Selective myeloid leucocyte depletion was effective for remission induction and improving patients' quality of life. Baseline demographics such as disease activity level, duration and corticosteroid dependency appear to predict response to GMA. Additionally, patients with a first UC episode who were drug naive responded well to GMA and achieved a favorable long-term disease course by avoiding pharmacologics from an early stage of their inflammatory bowel disease. These findings should help to end unnecessary use of medical resources by targeting GMA to patients who may respond well.