Fecal incontinence
Fecal incontinence (FI), also known as anal incontinence, or in some forms encopresis, is a lack of control over defecation, leading to involuntary loss of bowel contents—including flatus (gas), liquid stool elements and mucus, or solid feces. FI is a sign or a symptom, not a diagnosis. Incontinence can result from different causes and might occur with either constipation or diarrhea. Continence is maintained by several interrelated factors, including the anal sampling mechanism, and usually there is more than one deficiency of these mechanisms for incontinence to develop. The most common causes are thought to be immediate or delayed damage from childbirth, complications from prior anorectal surgery (especially involving the anal sphincters or hemorrhoidal vascular cushions), altered bowel habits (e.g., caused by irritable bowel syndrome, Crohn's disease, ulcerative colitis, food intolerance, or constipation with overflow incontinence), and receptive anal sex. An estimated 2.2% of community dwelling adults are affected.
Fecal incontinence
There is a continuous spectrum of different clinical presentations from incontinence of flatus (gas), through incontinence of mucus or liquid stool, to solids. The term "anal incontinence" often is used to describe flatus incontinence, however it is also used as a synonym for FI generally. It may occur together with incontinence of liquids or solids, or it may present in isolation. Flatus incontinence may be the first sign of FI. Once continence to flatus is lost, it is rarely restored. Anal incontinence may be equally disabling as the other types. Fecal leakage, fecal soiling and fecal seepage are minor degrees of FI, and describe incontinence of liquid stool, mucus, or very small amounts of solid stool. They cover a spectrum of increasing symptom severity (staining, soilage, seepage and accidents). Rarely, minor FI in adults may be described as encopresis. Fecal leakage is a related topic to rectal discharge, but this term does not necessarily imply any degree of incontinence. Discharge generally refers to conditions where there is pus or increased mucus production, or anatomical lesions that prevent the anal canal from closing fully, whereas fecal leakage generally concerns disorders of IAS function and functional evacuation disorders which cause a solid fecal mass to be retained in the rectum. Solid stool incontinence may be called complete (or major) incontinence, and anything less as partial (or minor) incontinence (i.e. incontinence of flatus (gas), liquid stool and/or mucus).