Association of Inflammatory Bowel Disease with Familial Mediterranean Fever in Turkish Children

Background And Aims: Inflammatory bowel disease (IBD) and familial Mediterranean fever (FMF) share common clinical and biological features. The prevalence of other inflammatory diseases, including IBD, is increased in FMF. We investigated the presence of IBD accompanying FMF in patients who were being followed up with a diagnosis of FMF and the relation of IBD with the MEFV gene mutation.

Methods: A total of 78 children with FMF were enrolled in the study. The patients were included in the study independent of the presence of complaints. Colonoscopy for IBD was performed if any of the following was present: blood mixed with mucus in the stool; chronic diarrhea (loose and frequent stools lasting >4 weeks); abdominal pain incompatible with FMF (localized in a certain part of the abdomen, not occurring during attacks, >3 days); and positive IgA and IgG anti-Saccharomyces cerevisiae antibodies and perinuclear antineutrophil cytoplasmic antibodies. MEFV gene mutations were analyzed in patients diagnosed as having IBD and FMF.

Results: Of the 78 patients with a diagnosis of FMF, colonoscopy was performed and biopsy samples were taken in 20 patients (25.6%) who had abdominal pain incompatible with FMF, chronic diarrhea, bloody stools, and/or positive perinuclear anti-neutrophil cytoplasmic antibody or anti-Saccharomyces cerevisiae antibody. Histopathological examination resulted in a diagnosis of IBD in 12 of the 78 patients (15.4%). MEFV gene mutations were present in all 12 patients diagnosed as having IBD. We observed M694 V mutations in 5 of 12 patients (41.7%), M680I mutations in 3 (25%), K695R mutations in 3 (25%), and E148Q mutations in 1 (8.3%).

Conclusions: We found that the number of patients with FMF was higher than the number with IBD in the general population. When IBD accompanied FMF, the most common mutation was M694 V; however, the high rate (25%) of K695R mutation in our patients with FMF and IBD was not observed in previous studies.