Microscopic colitis found together with celiac disease in a female population is associated with one episode of lymphocytic colitis

Background Microscopic colitis (MC) is considered a chronic disease associated with autoimmune disease, smoking, and drugs. The aim was to examine the association between MC and celiac disease, adjusted for smoking, considering subtypes and clinical course of the disease in a retrospectively collected female cohort. Methods Women ( n = 240), ≤ 73 years, diagnosed as MC in medical records or pathological registers were invited. One hundred and fifty-eight women accepted to be included. Participants completed a study questionnaire about sociodemographic factors, lifestyle habits, and medical history; the Rome III questionnaire; and the visual analog scale for irritable bowel syndrome (VAS-IBS). Participants were categorized into collagenous colitis (CC) ( n = 92) and lymphocytic colitis (LC) ( n = 66) or MC with one episode of the disease ( n = 70) and refractory MC ( n = 88). Presence of IBS-like symptoms were noted. Blood samples were collected and analyzed for anti-transglutaminase antibodies. Differences between groups were calculated and logistic regression was adjusted for smoking habits. Results MC and celiac disease debuted simultaneously in half of the cases. Celiac disease was most prevalent in LC (12.1% vs. 3.3%; p = 0.05) and MC with one episode (12.9% vs. 2.3%; p = 0.01). Anti-transglutaminase antibodies were found in one patient with one episode of MC. Corticosteroid use was most often found in CC (37.0% vs. 21.2%; p = 0.037) and refractory MC (38.6% vs. 20.0%; p = 0.015). Past smokers were most prevalent in patients with one episode of MC (54.3 vs. 29.5%; p = 0.007). Current smoking was the smoking habit with highest prevalence of IBS-like symptoms. When adjusted for smoking habits, celiac disease was associated with LC (OR: 4.222; 95% CI: 1.020–17.469; p = 0.047) and tended to be inversely associated with refractory MC (OR: 0.210; 95% CI: 0.042–1.506; p = 0.058). Conclusion Celiac disease is most common in patients with one episode of LC. The question remains whether LC in combination with celiac disease should be classified as celiac disease or two different entities.