MEFV Mutations in IBD Patients: A Systematic Review and Meta- analysis.

BACKGROUND AND AIMS:Several studies have suggested that mutations in MEFV, the gene responsible for familial Mediterranean fever (FMF), are frequently detected in inflammatory bowel disease (IBD) patients. We aimed to provide further evidence regarding a potential correlation between MEFV gene mutations and IBD by identifying all relevant studies and analyzing their results. METHODS:EMBASE, PubMed/MEDLINE, and Google Scholar were used to identify all studies that published until January 2021 and reported MEFV mutation patterns in patients with ulcerative colitis (UC), Crohn's disease (CD) and indeterminate colitis (IC) with or without a control group. The Newcastle-Ottawa quality assessment scale was used to appraise the quality of the included studies. RESULTS:Thirteen observational studies, including 937 patients and 977 controls, were analyzed. MEFV mutation rate in IBD patients was 0.238 (95%CI: 0.209-0.270; I 2 =95%); MEFV mutated alleles were more frequent in IBD patients when compared with controls (p=0.03 for UC, p=0.01 for CD and IC). Subgroup analysis indicated that MEFV mutations were increased in patients with IC when compared with UC and CD (I 2 =91%, p<0.001). Patients with extra-intestinal manifestations and pancolitis had 2.57 (95%CI 1.07-6.14; p=0.03) and 2.02 (95%CI: 1.01-4.04, P=0.049) odds ratios to carry MEFV mutant genotypes, respectively. Exon 10 mutations had the most serious impact. No source of heterogeneity was detected. CONCLUSIONS:MEFV mutations are common in IBD and are linked with the presence of extra-intestinal manifestations and pancolitis. Further research to assess the clinical significance and evolutionary significance of MEFV mutations in IBD patients is warranted.