Introduction: Recently it has been reported that prevalence of fructose intolerance (FI) in patients with functional gastrointestinal disorders range between 38% -75%.
Objective: To determine the prevalence of FI in subjects diagnosed with irritable bowel syndrome (IBS).
Methods: We studied 25 subjects (17 women, average age 36 years) with IBS (Rome II) and 25 healthy controls (14 women, mean age 37 years) who underwent a breath test after oral loading with fructose (Gastrolyzer ®, Bedfont Scientific Ltd., UK). The load consisted of 25 grams of fructose dissolved in 250 ml of water (10% solution). Breath test analysis of the particles per million (ppm) of hydrogen exhaled were performed every 15 minutes for 3 hours. The fructose breath test was considered positive when concentrations of hydrogen were higher than at 20 ppm or a raising greater than 5 ppm in 3 consecutive samples was detected.
Results: According to the Rome II criteria, 10 patients (40%) had IBS-C, 9 (36%) had IBS-D and 6 (24%) had IBS-M. Thirteen (52%) of IBS patients had IF, while only 4 (16%) of control subjects (p = 0.01). Patients with IBS and fructose intolerante tend to suffering from diarrhea predominant IBS (p = 0.053).
Conclusions: Fructose intolerance may be responsible for gastrointestinal symptoms in at least half of IBS patients, especially in the group of patients with IBS-D.