Relationship Between Cytomegalovirus Infection and Steroid Resistance in Inflammatory Bowel Disease: A Meta-Analysis

BACKGROUND AND AIMS: Steroid resistance presents an administration difficulty in inflammatory bowel disease (IBD). The reason of steroid resistance is still unclear, but cytomegalovirus (CMV) infection may be a potential cause in some IBD patients. We carried out a meta-analysis to investigate the relationship between CMV infection and steroid-resistant IBD. METHODS: The PubMed, EMBASE, and Cochrane Library databases were searched up to June 2014, with no language restrictions, for observational studies. Additional references were obtained from reviewed articles. RESULTS: Eleven studies involving 867 IBD patients were included in the meta-analysis. Steroid resistance rate was 70.0 % in CMV-positive IBD patients, which was significantly higher than that in CMV-negative IBD patients (RR = 2.12, 95 % CI = 1.72–2.61). There was significant heterogeneity in the included eleven studies (I(2) = 57.6 %). When the only one study with a few patients was excluded, sensitivity analysis suggested a similar outcome (RR = 2.07, 95 % CI = 1.80–2.39, 10 studies). Based on the funnel plot and Egger’s test, we considered that there was a probable publication bias. CONCLUSION: Our meta-analysis suggests that CMV-positive IBD patients have a nearly double risk of steroid resistance compared with CMV-negative IBD patients, indicating that CMV infection is a probable cause of steroid-resistant IBD.