The incidence of adult type hypolactasia in patients with irritable bowel syndrome.

Introduction: The incidence of lactose intolerance in irritable bowel syndrome (IBS) varies in the literature (27-72%). Primary adult lactase deficiency (adult type hypolactasia) is the most common type of primary enzyme deficiency. Complaints related to lactose intolerance may overlap with the symptoms of IBS. Aim: To assess the prevalence of primary hypolactasia in patients with IBS. Material and methods: The study included 56 patients with IBS diagnosed based on the Rome III criteria and 23 healthy people. All study participants completed a questionnaire on IBS symptoms and lactose intolerance, and they underwent a hydrogen breath test (HBT) with lactose. In the group of patients with positive results of HBT, the polymorphism C/T -13910 and G/A -22018 in the promoter of the LCT gene encoding lactase was determined. Results: Lactase deficiency was diagnosed in HBT in 34 (60.7%) patients with IBS and in the control group - in 10 (43.5%). Primary adult type hypolactasia was confirmed in 78.9% (n = 30; 79.3% in the study group; 77.8% in the control group). There were no statistically significant differences in the occurrence of LCT gene polymorphisms in particular IBS subtypes. Adult type hypolactasia was significantly more common in patients with severe than moderate and mild enzyme deficiency in HBT (p < 0.05). Conclusions: The incidence of lactase deficiency in IBS patients is not different from that found in healthy subjects. Nevertheless, irrespective of the IBS subtype, lactose intolerance may pose additional issues in patients with IBS and requires the targeted treatment.

The prevalence of celiac disease in patients with irritable bowel syndrome and its subtypes.

INTRODUCTION: Irritable bowel syndrome (IBS) and celiac disease (CD) share some gastrointestinal symptoms. Celiac disease should be considered in a differential diagnosis of IBS. AIM: To estimate the prevalence of predispositions to CD in patients with IBS and its subtypes. MATERIAL AND METHODS: The study included 48 patients (40 women, 8 men; average age: 41.1 ±14.6 years) with IBS, and a control group: 20 healthy volunteers. All participants completed a questionnaire on their current gastrointestinal symptoms and had a blood sample taken to determine the HLA-DQ2/DQ8 antigens and serum concentration of anti-tTG IgA and anti-DGP IgA and IgG. RESULTS: The presence of HLA-DQ2 or DQ8 was found in 50% of patients (n = 24) with IBS. In the control group the presence of HLA-DQ2 was found in 4 (20%) patients and nobody had HLA-DQ8. Increased levels of anti-tTG IgA were found in 5 (10.42%) patients with IBS, anti-DGP in 4 (8.33%), and anti-DGP IgG in 3 (6.25%). In the control group positive test result for anti-tTG was found in 2 (10%) patients; nobody had elevated anti-DGP IgA or IgG. A concomitant positive result of genetic testing and any elevated serum antibodies specific to CD was found in 12.5% of IBS patients (n = 6) and in none of the control group. CONCLUSIONS: Patients with IBS, regardless of the subtype, significantly more often than healthy controls have the predisposing genetic factors (HLA-DQ2/DQ8) underlying the development of CD.