[Intestinal infection and irritable bowel syndrome]

To determine whether intestinal infection plays a role on the pathogenesis of irritable bowel syndrome (IBS).

295 patients who had no previous history of functional bowel disorder had received treatment for dysentery (n = 235) or for acute bowel infection at the hospital between April-October, 1998, were followed up for 1 - 2 years and evaluated for their subsequent bowel habits. A cohort study of 243 subjects using their siblings, husbands or wives who did not have dysentery or acute bowel infection at the same period was taken as control. Furthermore, the contents of mRNAs of IL-1alpha, IL-1beta and IL-1ra in the mucosa at the terminal ileum and recto-sigmoid junctions were determined and compared using RT-PCR method in 30 IBS patients and 12 controls.

(1) Sixty-six (22.4%) patients were reported to have functional bowel disturbance, and 24 (8.1% total and 10.2% among cases of dysentery) developed IBS in the study group, whereas, only 7.4% had altered bowel habit and 0.8% had IBS in the control group (P < 0.01). (2) The risk of having functional bowel disturbance was higher in patients who suffered from a longer duration (> 8 d, OR = 3.5) of dysentery. (3) The IL-1beta mRNA level in the mucosa of terminal ileum and recto-sigmoid junction of IBS patients with dysentery was higher than that of controls and IBS patients without dysentery (P < 0.01).

Intestinal infection plays a role on the pathogenesis of IBS through some immunological factors.