Lactose intolerance in different types of irritable bowel syndrome in north Indians.

ABSTRACT

BACKGROUND: Twenty-five patients of irritable bowel syndrome (IBS) and 25 normal healthy individuals serving as controls, were studied for lactose intolerance. METHODS: Hydrogen breath test was used as an investigation after giving 50 g of oral lactose. Clinically, the patients were classified into 3 types of IBS. RESULTS: Eleven (44%) out of 25 patients belonged to diarrhoeal type of IBS, 7 (28%) of 25 patients to spastic and rest 7 (28%) of 25 patients had features of both types of symptoms. Lactose hydrogen breath test was abnormal in 9 cases (82%) of 11 diarrhoeal type of IBS which was significantly higher (p < 0.02) than controls. However, the difference of abnormal hydrogen breath test between spastic type of IBS and patients with features of both types was not significant as compared to controls. CONCLUSIONS: These results suggest that patients with diarrhoeal type of IBS have a higher incidence of lactose intolerance as compared to spastic type as well as patients with features of both types.