Background: Irritable bowel syndrome (IBS) is a common disorder of gut-brain interaction with multifactorial pathophysiology, including post-infectious mechanisms. In endemic regions, intestinal parasitic infections remain highly frequent and may contribute to persistent gastrointestinal symptoms; however, their role in IBS is often under-recognized and insufficiently studied. This study aimed to compare the frequency and species distribution of intestinal parasitic infections among IBS patients and healthy controls and to evaluate their independent association with IBS in an endemic setting.
Methods: A hospital-based case-control study was conducted in 2023, including 100 IBS patients diagnosed according to Rome IV criteria and 100 age-matched healthy controls. Stool samples were examined using World Health Organization-recommended parasitological techniques, including direct microscopy, concentration methods, staining, and culture. Multivariate logistic regression analysis was performed to assess factors independently associated with IBS.
Results: Intestinal parasitic infections were significantly more frequent among IBS patients compared with controls (P < 0.001), with Entamoeba histolytica and Giardia lamblia predominant. Parasitic infection showed a strong independent association with IBS, along with female sex and short sleep duration.
Conclusion: Intestinal parasitic infections are significantly associated with IBS in endemic regions. These findings suggest that parasitological evaluation may warrant consideration during IBS assessment in selected settings.
Keywords: Entamoeba histolytica; Giardia lamblia; Intestinal parasitic infections; Irritable bowel syndrome; Post-infectious IBS.
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