Lactose Intolerance in Patients Fulfilling The Rome-III Criteria for Irritable Bowel Syndrome in a Tertiary Hospital in Bangladesh

Abstract

Irritable bowel syndrome (IBS) is a common disorder in our daily clinical practice which is a chronic, relapsing gastrointestinal problem, characterized by abdominal pain, bloating and changes in bowel habit. Symptoms caused by lactose malabsorption may be confused with those of IBS and the two disorders can also co-exist in the same person. The aim of this study was to see the prevalence of lactose intolerance in persons with IBS and also to see the prevalence of lactose intolerance in persons without IBS. This observational study was carried out in the Department of Gastroenterology of BSMMU, Dhaka during July 2010 to September 2011.Total 100 patients fulfilling Rome III criteria for IBS and 30 age and sex matched people without having any symptoms of IBS or organic gastrointestinal disease or systemic disease were enrolled and were advised for lactose tolerance test (LTT). For lactose tolerance test fasting blood glucose level was measured, then 50gm of lactose was given orally and blood glucose was measured after 30mins of ingestion of lactose. An increase less than 20mg/dL over base line after 30 mins. indicate positive lactose intolerance. Lactose intolerance was found 62 (62%) in IBS and 13 (43.3%) in control group (p>0.05). Among the lactose intolerance patients, maximum patients were service holder in both group, which was 43.5% and 53.8% in IBS and control group respectively. The mean age was 31.47±8.36 years in IBS and 37.77±10.44 years in control group in patients with lactose Intolerance. Patients with lactose intolerance, the mean blood glucose during fasting was 5.0±0.49 mmole/L in IBS and 5.28±0.56 mmole/L in control group. After lactose the mean blood glucose was 5.67±0.49 mmole/L and 5.97±0.55 in IBS and control group respectively. Our recommendation is to perform lactose tolerance test before the diagnosis of IBS. Further large scale study is suggested.