Should we look for Celiac Disease in Irritable Bowel Syndrome?

Abstract

Irritable Bowel Syndrome (IBS) is a prevalent disease around the world. It is estimated that 10%-20% of the general population suffered from the disease, regards to standard scales like ROME II.1-3 It is about 2 times more prevalent in women compared to men and it is difficult differentiating from celiac disease. Celiac is a type of mal-absorption in small intestinal which is caused in genetically predisposed individuals exposed to gluten-contained regiment.1 Studies in European countries showed that more than 1% of general population has celiac disease.4,5 Recent advances in diagnostic methods and achievement to diagnostic tests with high sensitivity and specificity result in higher prevalence of the celiac disease than what was estimated before and can be presented with atypic or non-gastrointestinal symptoms. Symptoms of the disease can be similar to IBS, thus celiac patient may be treated as IBS. Recent studies have been reported increasing the prevalence of celiac in IBS patients compared to normal population.3 Celiac serologic tests are not requested routinely in IBS patients. Celiac disease is treatable and recovered with gluten-free diet; therefore this study was designed to determine the prevalence of celiac in IBS patients to decide about considering this in lab test requests for IBS work-up. This case-control study was done on IBS patients (diagnosed by ROME II criteria) referred to gastrointestinal clinic during a 2-years period (2006-2008) and including in the study voluntarily. IBS patients were labeled when other laboratory tests were reported normal (Na,K,Bun,Cr,CBC,ESR,T3,T4,T3RU and colonoscopy & sigmoidoscopy in patients older than 50 years-old) and have ROME II criteria. Control group were whom without any gastrointestinal disease, chronic disease or IBS and were age and sex matched with case group. One hundred and sixty one cases and 172 controls were enrolled in the study .All had informed consent and demographic questionnaires were completed for all, and then referred to the certain laboratory. Tissue transglutaminase antibody was checked by ELISA method (Orthentek kit), in the research laboratory. Mean age was 31.82± 10.95 years in cases and 32.97±13.08 years in controls. Male to female ratio was about 0.8 in both groups. (p=0.52). Diarrhea predominance was reported in 87.2% and others were constipation predominant (p =0.32). In both groups Persian tribe was the most frequent type. One positive TTG-Ab was seen in each group (p=0.66). These individuals were women from Persian tribe. In the case group, this positive patient was in 50-59 years-old age group and diarrhea predominant. In the control group she was in 30-39 years old age group. As the results showed the prevalence serologic of celiac, characterized by tTG antibody was 0.62% in IBS patients and 0.58% in healthy controls. Other similar studies in Turkey,6 and United Kingdome,7 reported no positive tTG-Ab in IBS patients. On the other hand, some authors detected a low prevalence of positive celiac cases in IBS.8,9 In Iran, it was reported a little higher in IBS patients compared to healthy controls.8,10 In the most recent study done in Tehran(2008),no one had positive serologic test of IgA anti-TTG antibody in IBS patients.11 According to the wide variation in the prevalence of celiac disease exists between different setting with different characteristics of patients and various serological tests, now it is the time to decide about considering celiac serologic tests in suspected IBS patients, keeping in mind these controversies. Due to the AGA guidelines and recent publication of the ROME working team, serologic tests for CD in the work up of all IBS patients is not recommended. Clinical characteristics and prevalence of CD in the studied region are among the indicators which is suggested by ROME III to be considered when IBS patient is referred to Gastroenterology clinic.1 As it has been discussed in other studies,11 physician clinical judgment is the cornerstone of making decision about referring IBS patient for CD lab test.