Background/Purpose: Takayasu’s arteritis (TAK) is a chronic vasculitis of large-vessels, mainly affects the aorta and its branches in the middle-aged females. There are reports regarding the concurrence of inflammatory bowel disease (IBD) and TAK. Microscopic colitis (MC) has been demonstrated in inflammatory rheumatic diseases such as spondylarthropathies which has been linked to an ethiopathogenetical association between two diseases. MC as an IBD subgroup has not been investigated in TAK, so far. We aim to assess the presence of MC in TAK patients who have no clinically overt IBD symptoms.

Methods: We cross-sectionally assessed TAK patients, between the ages of 18-65, who were diagnosed according to ACR criteria. Disease activity was evaluated by Kerr’s criteria. Age and sex matched irritabl bowel syndrome (IBS) patients were selected as control group. Study subjects who have been on MC inducing medications, such as NSAIDs, PPI, anti-physchotic or anti-depressant and having co-morbidities were excluded. All patients and controls have been interviewed for IBD and IBS symptoms by the questionnaires of WHO guideline and Rome III criteria, respectively. Lower endoscopic procedure was performed with at least 5 random biopsies taken from different colonic segments and terminal ileum within the following 2 weeks after the research visit. A blinded expert pathologist evaluated the specimens for the thickness of the collagen band, the degree of inflammatory infiltration in the lamina propria, and the number of intraepithelial lymphocytes according to an algorythm proposed for MC assessment by Langner C et al.¹. Lymphocytic and collagen colitis were defined as the subgroups of MC. Incomplete colitis has also been defined in the algorythm.

Results:

Thirty TAK patients (29 female) with the mean age of 35±11 (20-59), total disease duration of 107±79 months (3-286) and 10 female IBS controls with the mean age of 38±13 were included into the study. Type 2 vascular involvement was the most common (64%) pattern in the cohort. Nine of 30 (30%) TAK patients have active disease at the time of endoscopic procedure. MC was not demonstrated in any patients with IBS. All but one TAK patients had normal endoscopic findings. Erythema on the entire colonic mucosa as the only pathological endoscopic finding was demonstrated in one patient. The examination of terminal ileum was found  normal in both TAK and control groups. Three patients (10%) were full-filled LC criteria of MC. Incomplete LC was determined in additional 6 patients (20%). LC was found significantly higher among the patients with active TAK subgroup compared with inactive patients (p= 0.03, OR= 5,7).

Conclusion: MC was found significantly high in TAK patients who had no overt IBD symptoms/diagnosis. This preliminary report from this ongoing study supports that this association might have a pathopyhsiological relevance.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/microscopic-colitis-in-patients-with-takayasu-arteritis-a-potential-association-between-the-two-disease-entities/