Celiac Disease and Microscopic Colitis Frequencies İn Patients With Diarrhoea Predominant Irritable Bowel SyndromeIntroduction: Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disease in the general population. Diagnose of the IBS is based on a specific constellation of symptoms (Roma III criteria). Depending on the main symptom, the disease is classified as diarrhoea predominant IBS (IBS-D), constipation predominant IBS (IBS-C) and mixed type IBS. However, symptoms of the IBS-D may overlap with celiac disease (CD) and microscopic colitis (MC).Objective: In this study, we aimed to investigate the frequency of CD and MC in patients diagnosed as IBS-D according to Roma III criteria.Patients and Method: Fifty one patients (29 F, 22 M) with IBS-D and 40 subjects as a control group (17 F, 23 M) whom were suffering from rectal bleeding and diagnosed as having hemorrhoid were recruited to the study and all of them underwent for the colonoscopy. For histological examination, multiple biopsies were obtained from ascendant, transverses and descendent colon. In addition, the presence of tissue transglutaminase antibodies (tTG) IgA and IgG were searched by ELISA method from all study subjects. Endoscopy with biopsy from the second part of duodenum was performed in those with at least one of the antibody positivity and samples were investigated histopathologically. Also patients who had positive serology but normal histopathology results were analyzed genetically for celiac disease.Results: The mean ages were 39.21±14.05 years in the patient group and 44.55±11.86 years in the control group. There were no significant differences between the groups by means of age and sex (P=0.06 and P=0.21). In the IBS-D group, tTG IgA and/or tTG IgG were found to be positive in 6 patients (11.7%). In this sero-positive group, one of the patient was IgA whereas five of them were IgG was positive and the histological evaluation of the intestinal tissues were found normal. Genetic analyses for the CD were resulted positive for the HLA DQ2 in 5 of the 6 patients (83.3%) and negative in one patient (16.6%). However, HLA DRB1*04 was positive in 3 of the 6 patients (50%) and from these 3 patients, 2 of them were positive for both HLA DQ2 and HLA DRB1*04. Three patients whom were negative for HLA DRB1*04 were also positive for HLA DQ2. Diagnosis of these 6 patients were regarded as latent/potentiel CD (L/P-ÇD). Control group were found to be negative for the tTG IgA and/or tTG IgG. There was a significant difference between IBS-D and control group for the latent/potential CD (L/P-CD) frequency (11.7% vs. 0.0%, P=0.03). In the IBS-D group, 5 of the patients were diagnosed with MC (9.8%), 3 of them were diagnosed with lymphocytic colitis (LC), 2 of them had collagenous colitis (CC). In the control group, 2 of the patients were found to have MC (5%) including CC type. There was no significant difference for the MC frequency between IBS-D and control groups (9.8% vs. 5.0%, P=0.46).Conclusion: Prevalence of CD and MC was reported to be higher in selected patient groups with no response to diet and symptomatic medication İBS. This study showed that diagnoses of CD and MC should be kept in mind in the all types of IBS patients.Keywords: Celiac disease; diarrhoea predominant irritable bowel syndrome; collagenous colitis; lymphocytic colitis; microscopic colitis.

Giriş: İrritabl barsak sendromu (İBS) genel populasyonda en sık karşılaşılan gastrointestinal rahatsızlıklardandır. Tanısı semptom bazlı kriterlere (Roma III) dayanarak konulmaktadır. Baskın semptoma göre diyare, konstipasyon ve mikst tip olmak üzere alt tipleri vardır. Özellikle diyare predominant İBS (İBS-D) ile çölyak hastalığı (ÇH) ve mikroskopik kolitin (MK) semptomlarında örtüşme olabilir.Amaç: Bu çalışmada, Roma III kriterlerine dayanarak tanı konulan İBS-D'li hastalarda ÇH ve MK sıklığını araştırmayı amaçladık.Hastalar ve yöntem: Çalışmaya İBS-D tanısı alan 51 hasta (29 kadın, 22 erkek) ve kontrol grubu olarak taze rektal kanama nedeni ile kolonoskopisi yapılan ve sadece hemoroid saptanan 40 birey (17 kadın, 23 erkek) alındı. Hasta ve kontrol grubunun tümüne kolonoskopi yapılarak çıkan kolon, transvers kolon ve inen kolondan çoklu biyopsiler alınarak histolojik inceleme yapıldı. Ayrıca çalışmaya dahil edilen tüm bireylerde Enzyme Linked Immunoabsorbant Assay (ELISA) yöntemi ile doku transglutaminaz antikorları (tTGA) IgA (Immünglobulin A) ve IgG (Immünglobulin G) bakıldı. En az bir antikor pozitifliğinde duodenum ikinci kesiminden endoskopik biyopsi alınarak histopatolojik inceleme yapıldı. Serolojisi pozitif olan ancak histopatolojik incelemesi normal olan hastalara çölyak genetik analizi yapıldı.Bulgular: Hasta grubu yaş ortalaması 39.21±14.05 yıl, kontrol grubu yaş ortalaması ise 44.55±11.86 yıl idi. Hasta ve kontrol grubu arasında yaş ve cinsiyet bakımından fark yoktu (p=0.06 ve p=0.21).İBS-D grubunda 6 hastada (%11.7) tTGA pozitif bulundu. Bunların birinde doku transglutaminaz (tTG) IgA antikoru pozitifken beşinde tTG IgG antikoru pozitifti. Antikor pozitifliği saptanan 6 hastanın tümünde histoloji normal bulundu ve çölyak genetik analizleri yapıldı. Altı hastadan beşinde HLA DQ2 pozitif (%83.3), birinde (%16.6) negatif idi. HLA DRB1*04 ise 6 hastanın üçünde (%50) pozitif idi. İki hastada hem HLA DQ2 hem HLA DRB1*04 pozitif, 3 hastada HLA DQ2 pozitif HLADRB1*04 negatif idi. HLA DQ2'si negatif olan hastanın HLA DRB1*04'ü pozitif idi. Bu 6 hasta latent/potansiyel ÇH (L/P-ÇH) olarak kabul edildi. Kontrol grubunda ise tTG antikoru pozitif bulunan hasta yoktu. İBS-D grubu ile kontrol grubu arasında L/P-ÇH sıklığı bakımından anlamlı fark gözlendi (%11.7 vs %0.0, p=0.03).İBS-D grubunda üçü lenfositik kolit (LK) ikisi kollajenöz kolit (KK) olmak üzere 5 hastada (%9.8) MK saptandı. Kontrol grubunda ise her ikisi de KK olmak üzere 2 hastada (%5) MK saptandı. İBS-D grubu ile kontrol grubu arasında MK sıklığı bakımından anlamlı fark gözlenmedi (%9.8 vs %5.0, p=0.46).Sonuç: ÇH ve MK özellikle seçilmiş hasta grubunda (diyete ve semptomatik tedaviye yanıtsız İBS-D) yüksek oranda birlikte olabilir. Bizim çalışmamızda olduğu gibi seçilmemiş hasta grubunda da ÇH ve MK tanısının akılda tutulması yararlı olabilir.Anahtar Sözcükler: Çölyak hastalığı; diyare predominant irritabl barsak sendromu; kollajenöz kolit; lenfositik kolit; mikroskopik kolit.