Published online Jan 21, 2016. doi: 10.3748/wjg.v22.i3.1321
Peer-review started: May 5, 2015
First decision: August 26, 2015
Revised: October 12, 2015
Accepted: November 30, 2015
Article in press: November 30, 2015
Published online: January 21, 2016
Processing time: 262 Days and 12.8 Hours
AIM: To identify definitions of cytomegalovirus (CMV) infection and intestinal disease, in inflammatory bowel disease (IBD), to determine the prevalence associated with these definitions.
METHODS: We conducted a systematic review and interrogated PubMed, EMBASE and Cochrane for literature on prevalence and diagnostics of CMV infection and intestinal disease in IBD patients. As medical headings we used “cytomegalovirus” OR “CMV” OR “cytomegalo virus” AND “inflammatory bowel disease” OR “IBD” OR “ulcerative colitis” OR “colitis ulcerosa” OR “Crohn’s disease”. Both MeSH-terms and free searches were performed. We included all types of English-language (clinical) trials concerning diagnostics and prevalence of CMV in IBD.
RESULTS: The search strategy identified 924 citations, and 52 articles were eligible for inclusion. We identified 21 different definitions for CMV infection, 8 definitions for CMV intestinal disease and 3 definitions for CMV reactivation. Prevalence numbers depend on used definition, studied population and region. The highest prevalence for CMV infection was found when using positive serum PCR as a definition, whereas for CMV intestinal disease this applies to the use of tissue PCR > 10 copies/mg tissue. Most patients with CMV infection and intestinal disease had steroid refractory disease and came from East Asia.
CONCLUSION: We detected multiple different definitions used for CMV infection and intestinal disease in IBD patients, which has an effect on prevalence numbers and eventually on outcome in different trials.
Core tip: The use of different definitions for cytomegalovirus (CMV) infection and CMV intestinal disease in inflammatory bowel disease (IBD) patients has great impact on the reported prevalence rates (definitions with highest prevalence: positive serum PCR (CMV infection) and tissue PCR > 10 copies/mg tissue (CMV intestinal disease)). In addition, prevalence rates depend on the studied population (highest prevalence: steroid refractory disease), and region (highest prevalence: East Asia). Our key message is not to develop more sensitive diagnostics to find CMV, but to organise a global consensus meeting on CMV in IBD to formulate one unified definition for clinically relevant CMV (intestinal) disease in IBD.