Post-infectious irritable bowel syndrome after a laboratory-proven enteritis

There are scarce data on risk factors for post-infectious irritable bowel syndrome (PI-IBS). The objective of this study was to determine the risk factors of developing PI-IBS following an acute infectious gastroenteritis (AGE) episode in which, by laboratory tests, the etiological agent was isolated. The study was conducted on patients admitted to a tertiary center of infectious diseases during three consecutive years. The patients were divided into two groups: a group consisting of patients admitted with AGE (with an isolated etiological agent) and a control group consisting of patients admitted for an acute upper respiratory tract infection (URTI). The subjects were recalled in our center 6 months after the admission and were evaluated with Rome III IBS diagnostic questionnaire and Bristol Stool Form Scale. The questionnaires were paper printed and directly filled in by the subjects. The response rate in the case group was 5% and in the control group 100%. The prevalence of PI-IBS was higher in patients with AGE, presenting a relative risk (RR) of 4.16 [95% confidence interval (CI), 1.89-9.17], statistically significant (P<0.001) vs. URTI. From 28 female patients, 22 patients (79%) developed PI-IBS and from 17 male patients, 3 patients (18%) had developed PI-IBS with a risk of 4.4 (95% CI, 1.56-12.65), P<0.001. Regarding the infectious etiology of the AGE, Campylobacter jejuni had the highest risk of developing PI-IBS, RR=1.2 (95% CI, 0.13-3.11), P=0.04 compared with the other agents with a lower risk. The risk to develop PI-IBS after AGE infection is 4.16 higher than after URTI. Female sex is a risk factor for PI-IBS, 79% of the female patients developed PI-IBS after AGE. The incidence of PI-IBS is highest in patients with Campylobacter jejuni AGE compared with the other agents.