The rates of postoperative endoscopic recurrence (PER) in patients with Crohn's disease (CD) are consistent. Anti-TNF therapy has been increasingly used in the postoperative setting, despite the lack of robust data in the literature on the measurement of trough levels and consequences of their use.
The aim of this review was to assess trough levels of infliximab (IFX) in CD patients after ileocolonic resections in correlation with the presence of PER.
We searched for studies that evaluated trough levels of IFX in patients with CD, who underwent ileocaecal resections, and correlated them with the presence of PER. We used MEDLINE through PubMed and CENTRAL Cochrane library databases, and after matching the inclusion criteria, the studies were methodologically evaluated with qualitative analysis of the data.
A total of 155 studies were initially identified in the databases search and only four matched the inclusion criteria. They comprised one prospective cohort study, one randomized controlled trial and two retrospective cohort studies, the last one performed in pediatric patients. This evidence suggested the correlation of PER with low trough levels of IFX and the presence of antibodies to the drug. The quality of the evidence generated varied from very low to high, due to the heterogeneity found between the studies and the risks of bias that were identified.
Low levels of IFX and the presence of antibodies to the drug were directly associated with increased PER rates in patients with CD, who underwent ileocolonic resections. Controlled and randomized clinical trials with adequate methodological quality are warranted to confirm the conclusions from this systematic review.