Mean Platelet Volume as a Biomarker for Disease Severity and Development of Pouchitis After Ileal Pouch-Anal Anastomosis

Abstract

Introduction: Recent studies have shown that mean platelet volume (MPV) could be used as a biomarker of current disease activity in inflammatory bowel disease (IBD), including both Crohn's disease (CD) and ulcerative colitis (UC). To date, studies evaluating MPV as a biomarker for future disease outcomes are limited. The objectives of this study were to first determine the association between MPV and need for surgery retrospectively, and secondly, to prospectively evaluate if MPV could be used as a prognostic biomarker for outcomes in patients with UC following ileal pouch-anal anastomosis (IPAA). Methods: This study evaluated patients from 1970 to 2015 at Cedars-Sinai IBD Center. Patients included in the retrospective portion of the study were those recruited to our IBD biorepository with more than 3 MPVs available. MPV data was evaluated at any time during their disease course. Patients included in the prospective portion of the study were those with UC and who underwent IPAA performed by a single surgeon. MPV data was collected before surgery. One investigator followed patients prospectively after the final stage of their IPAA. Pouchoscopies were performed every three months during the first post-operative year as part of routine surveillance. Final outcome and time to pouch specific complications (defined as months from closure of ileostomy) were recorded. Standard statistical analyses were performed to assess associations between outcome and MPV including age, gender, and ethnicity as covariates. Results: For the retrospective portion of the study, 113 patients who had any IBD-related surgery were compared to 880 patients who did not. Table 1 shows associations between MPV and need for surgery in CD, UC, and IBD overall. 215 patients were included in the prospective part of the study. Average MPV before surgery was 7.37 fL +/- 0.87 fL (normal 9.4-12.3). Table 2 shows the average MPV before surgery for each pouch-specific complication compared to patients with a normal pouch (n=109), which had an average MPV of 7.34 (0.85). The subsequent development of chronic pouchitis (table 2) and average time to development of Crohn's disease (p=0.02) were significantly associated with MPV before surgery.Table: Table. Significant Associations between MPV and Need for SurgeryTable: Table. Logistic Regression for MPV vs. Final Outcome following IPAAConclusion: Our data demonstrated that an inexpensive and commonly used lab parameter, MPV, is associated with need for surgery and, in a prospective cohort, with the development of chronic pouchitis after IPAA. Additional studies will be needed to replicate and extend these findings.