Fecal Incontinence in Patients with Irritable Bowel Syndrome: A Narrative Review

Fecal incontinence (FI) is the recurrent and uncontrolled passage of fecal material, in-cluding episodes of soiling or underwear staining. Irritable bowel syndrome (IBS) is a disorder of gut-brain interaction characterized by recurrent abdominal pain or dis-comfort associated with altered bowel habits, including diarrhea, constipation, or a mixed pattern. Although these conditions have traditionally been considered sepa-rately, increasing evidence suggests that they frequently overlap, especially in patients with diarrhea-predominant IBS. In this setting, FI should not be regarded as a simple consequence of anal sphincter weakness. Loose stools, urgency, altered colonic transit, rectal hypersensitivity, anorectal sensorimotor dysfunction, pelvic floor impairment, and reduced continence reserve may interact and promote leakage. Additional struc-tural, iatrogenic, and patient-related factors may further increase susceptibility. The overlap is often underrecognized because many patients do not spontaneously report fecal leakage, despite its relevant impact on quality of life and daily functioning. A careful history, direct but non-stigmatizing questioning, physical examination, symp-tom assessment, and selective investigations are therefore essential to identify the dominant clinical phenotype and exclude secondary causes. Treatment should be indi-vidualized and progressive, combining optimization of bowel habits and IBS-directed strategies with anorectal rehabilitation and, when needed, more advanced FI-directed treatments. Recognizing FI as part of the clinical spectrum of IBS may improve diag-nostic accuracy, promote earlier treatment, and support a more integrated and pa-tient-centered approach to care.