Association of MALTectomy (appendectomy and tonsillectomy) and inflammatory bowel disease: a familial case-control study

There is some controversy regarding the prevalence of tonsillectomy and app endectomy among patients with Crohn's disease (CD) and a lower rate of appe ndectomy among patients with ulcerative colitis (UC). However. some environ mental and familial factors that could alter those figures have not been st udied. Objective: to explore the prevalence of MALTectomy (appendectomy and tonsil lectomy) among patients with 113D, stressing those factors that may be sign ificantly associated to it. Method: age-and-sex matched case-control study in patients with IBD, their relatives and the general population. Two hundred and eighty seven cases we re IBD patients (153 UC, and 134 CD), the "family control" group included 2 03 siblings and the population-based control group included 570 individuals . Potential confounding factors, such as smoking, educational level, oral c ontraceptive use, place of birth and residence up to the age of 15 years, w ere ruled out. Results: appendectomy and UC: 7% of UC patients had undergone appendectomy versus 20% (OR: 0.23; 95% Cl: 0.11-0.5; p < 0.0001) of controls. Appendecto my rates in families with at least one case of UC were 17/153 (6.3%) and 61 /306 (20%) in the control group (p < 0.001). Appendectomy and CD: Twelve pe r cent of CD patients had undergone appendectomy six months before the onse t of the disease versus 17 % among the control population (OR: 0.43: 95% CI : 0.29-0.95; p < 0.01). The frequency of appendectomy in families with at l east one case of CD was 22/221 (10%), which was significantly lower (p <0.0 5) than among the control group 45/264 (17%). No differences were found bet ween IBD patients and familial controls, Tonsillectomy and CD: Forty six pe r cent of CD patients had undergone tonsillectomy versus 39% of control pat ients (OR: 1.77; 95% Cl: 0.92-2.05; p=ns). Tonsillectomy and UC: Twenty eig ht per cent of UC patients had undergone tonsillectomy versus 39 % of the p opulation control group (OR: 1.07: 95 Cl: 0.57-1,25: p=ns). In fact, no dif ferences were found regarding the prevalence of tonsillectomies. Conclusions: appendectomy is not only less frequent among CD and UC patient s, but also among their relatives, thus suggesting the existence of environ mental and genetic factors with opposed etiological roles in IBD and append icitis.