Version July 2025
INTRODUCTION —
Fecal incontinence is a common but underreported problem that has a significant social and economic impact and significantly impairs quality of life [1-3].
Fecal incontinence refers to the involuntary loss of solid or liquid feces, whereas anal incontinence is a more general term that also includes loss of flatus. This topic will review the etiology and evaluation of fecal incontinence in adults. Our recommendations are largely consistent with the American College of Gastroenterology and European clinical practice guidelines [4,5].
The approach to flatulence is discussed elsewhere. (See "Overview of intestinal gas and bloating", section on 'Flatulence'.)
The management of fecal incontinence in adults is discussed in detail separately. (See "Fecal incontinence in adults: Management".)
EPIDEMIOLOGY
Prevalence — Estimates of the prevalence of fecal incontinence vary depending on the definition used and the study population [6-10]. Studies likely underestimate the prevalence of fecal incontinence, as many patients are reluctant to report it [11].
In a systematic review of 38 studies, the median prevalence of fecal incontinence was 7.7 percent (range 2 to 21 percent) [10]. However, there was significant heterogeneity across studies. In a United States population-based survey of over 70,000 adults ≥18 years old, 14 percent had experienced any fecal incontinence; among these, 33 percent reported stool leakage within the past week [12]. In the Rome Foundation Worldwide Study involving almost 55,000 individuals in 26 countries, the prevalence of fecal incontinence (using a more stringent definition of recurrent uncontrolled passage of fecal material for more than three months) was 1.6 percent (1.5 to 1.7) [13].
The prevalence of fecal incontinence increases with advancing age [10]. Rates are similar among males and females.
Risk factors — Risk factors for fecal incontinence include [8,10,14-17]:
●Older age
●Diarrhea
●Fecal urgency
●Urinary incontinence
●Diabetes mellitus
●Central adiposity
Other specific medical conditions and medications associated with fecal incontinence are discussed elsewhere. (See 'Medical conditions' below and 'Medication-related' below.)
PATHOPHYSIOLOGY
Normal defecation — Normal defecation involves a complex sequence of events that are initiated by the entry of stool into the rectum (figure 1) [18]. Progressive rectal distension leads to reflex relaxation of the internal anal sphincter. The urge to defecate increases as stool continues to enter the rectum from the sigmoid colon. When defecation is desired, the anorectal angle is voluntarily straightened (which is facilitated by squatting or sitting), and abdominal pressure is increased by straining. This results in descent of the pelvic floor, contraction of the rectum, and inhibition of the external anal sphincter, thereby evacuating the rectal contents.
Factors that maintain continence — Continence depends on several factors, including cognitive function, stool volume and consistency, colonic transit, rectal distensibility, anal sphincter function, anorectal sensation, and anorectal reflexes. Within the anorectum, anatomic barriers that help preserve continence include the rectum, internal anal sphincter, external anal sphincter, and puborectalis muscle.
●The rectum contains three distinctive semilunar mucosal folds, which help to maintain rectal capacity. The rectum can accommodate up to 300 mL without any significant increase in intraluminal pressure. Beyond 300 mL of volume, the intraluminal pressure increases and results in a feeling of urgency [18]. Retrograde colonic cyclic motor patterns have been hypothesized to act as a "rectosigmoid brake" to limit filling of the rectum [19,20].
●The internal anal sphincter is a thickened, circular smooth-muscle layer innervated by the enteric nervous system. It is tonically contracted and accounts for 80 to 85 percent of the anal canal resting pressure. The internal anal sphincter relaxes transiently in response to rectal distension, a reflex known as the anorectal inhibitory reflex. The role of the anorectal inhibitory reflex is not entirely clear, although it may permit the sampling of rectal contents by sensory receptors in the anal canal, thereby helping to distinguish solid from liquid stool or gas. It does not appear to be essential for continence since continence is preserved even with an absent anorectal inhibitory reflex, as typically occurs following ileoanal anastomosis [21].
●The external anal sphincter and the puborectalis muscle represent the voluntary components of fecal continence, since they are composed of striated muscle with somatic innervation (the external anal sphincter by the pudendal nerve and the puborectalis muscles by pelvic branches of S3 to S4). Despite their independent innervation, the external anal sphincter and puborectalis muscle function as a unit. Contraction of the external anal sphincter normally doubles the pressure in the anal canal, although this pressure cannot be sustained for more than a few minutes. A spinal reflex causes the external anal sphincter to contract during sudden increases in intraabdominal pressure, such as coughing or lifting, thereby helping to maintain continence [22].
●The puborectalis muscle is part of the pelvic diaphragm, which consists of the levator ani, pubococcygeus, iliococcygeus, and the puborectalis muscle. The puborectalis muscle originates from the pubic arch, loops posteriorly behind the rectum and then travels back to the pubic arch, thereby forming a sling around the anorectum. This angle (which is typically between 80 and 110 degrees at rest, and less than 80 degrees during voluntary squeeze) helps maintain continence by forming an anatomic barrier against the discharge of stool. Dysfunction of the levator ani muscle appears to have a strong association with the severity of incontinence [23].
Physiologic factors leading to loss of continence — Loss of continence can result from various abnormalities.
●Anal sphincter dysfunction – Anal sphincter dysfunction can occur due to weakness or injury to the sphincter muscles themselves or to the nerves that supply these muscles (eg, pudendal nerve injury or autonomic neuropathy).
●Alterations in rectal sensation – Alterations in sensory perception of the rectum can be due to problems in the peripheral, central or autonomic nervous systems. Patients with rectal hyposensitivity may not feel the urge to defecate, leading to stool being involuntarily expelled before the patient experiences the urge to defecate, or to fecal impaction and then overflow incontinence [24,25]. In contrast, patients with rectal hypersensitivity (eg, irritable bowel syndrome with predominant diarrhea) may have the frequent urge to defecate, which may lead to incontinence if a toilet is not readily accessible.
●Decreased rectal compliance – Decreased rectal compliance leads to increased frequency and urgency of bowel movements because the ability of the rectum to store fecal matter is reduced. This can lead to fecal incontinence even if sphincter function is normal.
●Altered stool consistency – Loose or liquid stools may overpower the normal continence mechanisms. Hard stools may cause fecal incontinence through constant inhibition of the internal anal sphincter tone and leakage of liquid stool around an impaction.
Incontinence is usually multifactorial, since these abnormalities often coexist. Mild impairment of any one mechanism will usually not cause incontinence, since the other mechanisms for maintaining continence can usually compensate. Patients with urge incontinence often have weakness of the external anal sphincter as well as decreased rectal capacity and rectal hypersensitivity, and patients with passive fecal incontinence often have weakness of the internal anal sphincter.
ETIOLOGIES
Sudden onset incontinence — Sudden onset fecal incontinence is uncommon and usually occurs with a change in bowel habits. There are several etiologies to consider:
●Acute diarrhea – Most commonly, sudden onset incontinence occurs in the context of a diarrheal illness (or acute diarrhea associated with new medications) and can be due to the change in stool consistency "unmasking" a subclinical defect in the ability to maintain continence (eg, mild anal sphincter weakness). The evaluation of diarrhea is discussed elsewhere. (See "Approach to the adult with acute diarrhea in resource-abundant settings" and "Approach to the adult with acute diarrhea in resource-limited settings".)
●Neurologic – Neurologic abnormalities that result in sudden loss of sphincter control can result in acute fecal incontinence. These include cauda equina injury or tumor, spinal cord injuries, epilepsy, and multiple sclerosis. In the majority of cases, the patient has additional symptoms corresponding to the diagnosis. Rarely, fecal incontinence may be the only manifestation of a neurologic condition [26].
●Anorectal trauma – Recent childbirth or anorectal surgery or trauma can cause fecal incontinence; typically this is apparent on history. The primary mechanism is through anal sphincter weakness due to either direct damage of the anal sphincter or trauma to the pudendal nerve. Fecal incontinence associated with childbirth is discussed in detail elsewhere. (See "Fecal and anal incontinence associated with pregnancy and childbirth: Counseling, evaluation, and management".)
Chronic fecal incontinence — Fecal incontinence most commonly presents as a long-standing and slowly progressive condition. Most patients have one or more of the following etiologies contributing to incontinence.
Prior childbirth — Fecal incontinence may occur immediately or many years after childbirth [27]. Risk factors for fecal incontinence later in life include fecal incontinence during pregnancy, maternal age over 35 years, prenatal body mass index over 30 kg/m2, instrumental vaginal delivery, spontaneous vaginal delivery, oxytocin augmentation, and weight of newborn greater than 4000 grams [28].
Prior anorectal trauma — Decreased anal sphincter pressures can result from anal trauma, such as after surgery on the anal sphincter or surrounding structures (eg, anal fistulas, hemorrhoids), pelvic radiation, or uncommonly after injection of botulinum toxin for anal fissures [29-31]. Anal intercourse has also been associated with fecal incontinence in both males and females [32]. In addition, radiation proctitis or prior proctectomy can cause incontinence through decreased rectal compliance.
Medical conditions — Various medical conditions have been associated with fecal incontinence:
●Inflammatory bowel disease — Multiple mechanisms increase the risk of fecal incontinence in patients with inflammatory bowel disease. Reduced rectal compliance and rectal hypersensitivity are likely contributors, particularly in ulcerative proctitis [33]. Changes in stool consistency during flares and a history of anorectal procedures related to their condition may also contribute.
●Neurologic conditions — Multiple neurologic conditions can lead to bowel dysfunction and fecal incontinence, including Parkinson disease, multiple sclerosis, spinal cord injury, and stroke. The mechanism is most likely through anal sphincter weakness and impaired rectal sensation.
●Diabetes mellitus — Diabetes mellitus with autonomic neuropathy can lead to fecal incontinence due to weakness of the internal anal sphincter and impaired rectal sensation. Patients with longstanding diabetes may also have altered stool consistency that contributes to fecal incontinence. (See "Diabetic autonomic neuropathy of the gastrointestinal tract", section on 'Diabetic diarrhea'.)
In addition, mechanical abnormalities of the colon or rectum (eg, rectal prolapse, prolapsed hemorrhoid, or mass) or illnesses that cause chronic diarrhea (eg, irritable bowel syndrome with predominant diarrhea or microscopic colitis) can lead to fecal incontinence. Another uncommon medical etiology is systemic sclerosis, in which fecal incontinence occurs due to anal sphincter weakness. Psychiatric etiologies include willful soiling and stool retention (which may be learned or due to medications) with subsequent fecal impaction causing incontinence.
Medication-related — Medications that can cause or contribute to fecal incontinence include agents that can cause loose stool, such as laxatives and magnesium-based supplements. Muscle relaxants can lower sphincter tone and contribute to incontinence. Anticholinergic agents, antidepressants, and antipsychotics can lead to constipation with subsequent fecal impaction and overflow incontinence. Glucagon-like peptide 1 (GLP-1)-based therapies can cause either diarrhea or constipation, potentially leading to fecal incontinence through multiple mechanisms.
Among postmenopausal women, hormone therapy is another risk factor. In a study of over 55,000 women participating in the Nurses' Health Study, the risk of developing fecal incontinence was increased in both past and current users of hormone therapy (hazard ratio [HR] 1.3, 95% CI 1.2-1.3 and HR 1.3, 95% CI 1.2-1.5, respectively) [34].
Fecal impaction — Fecal impaction can cause constant inhibition of the internal anal sphincter tone and leakage of liquid stool around the hard bolus; this is a common cause of fecal incontinence in older adults. Several factors may contribute to the development of fecal impaction in older adults including impaired cognitive function, immobility, rectal hyposensitivity, and inadequate intake of fluids. The diagnosis and management of fecal impaction is discussed elsewhere. (See "Management of chronic constipation in adults", section on 'Fecal impaction'.)
Idiopathic — Idiopathic fecal incontinence occurs most commonly in middle-aged or older women. Although by definition, the cause cannot be identified, it is probably due to denervation of pelvic floor muscles resulting from stretch injury to pudendal and sacral nerves as might occur following a prolonged vaginal delivery or defecatory straining [35]. Pathogenic contributors may include weakness of the anal sphincters and puborectalis, reduced rectal capacity, and rectal hypersensitivity [36].
INITIAL EVALUATION —
Evaluation of patients with fecal incontinence begins with a history and physical examination . We have a low threshold to proactively ask patients about fecal incontinence, as many individuals may not feel comfortable discussing these symptoms with their health care provider [11].
History — The goal of the history is to confirm and categorize the incontinence, identify alarm findings that warrant urgent testing, identify predisposing conditions and modifiable factors, and assess the impact on quality of life (table 1).
Confirming and categorizing incontinence — We take a detailed history regarding the characteristics of incontinence, including duration, severity, and frequency.
●Confirming true incontinence – The history should initially focus on determining whether fecal incontinence (ie, involuntary loss of feces) is present. Incontinence must be differentiated from frequency and urgency without loss of bowel contents [1]. Severe rectal urgency without incontinence may be due to inflammation, such as proctitis, decreased compliance secondary to chronic rectal inflammation or radiation, or visceral hypersensitivity related to irritable bowel syndrome.
●Categorizing incontinence – Some features of incontinence can identify potential etiologies. We specifically obtain the following information:
•Urge versus passive incontinence – Urge incontinence is characterized by the desire to defecate, but incontinence occurs despite efforts to retain stool. Passive incontinence is characterized by the lack of awareness of the need to defecate before the incontinent episode. Passive incontinence suggests weakness of the internal anal sphincter, whereas urge incontinence may indicate weakness of the external anal sphincter or decreased rectal capacity or rectal hypersensitivity. Urge incontinence of loose/liquid stool may be more common in patients with microscopic colitis or irritable bowel syndrome, whereas passive incontinence of solid stool may suggest neuromuscular dysfunction involving the pelvic floor [37].
•Onset and duration – In most cases, fecal incontinence has a gradual onset and longstanding duration. Sudden onset or acute fecal incontinence is almost always in the setting of a change in stool consistency (eg, diarrheal illness) or neurologic etiologies (eg, cauda equina syndrome). (See 'Sudden onset incontinence' above.)
•Frequency – While any amount of fecal incontinence can have a detrimental impact on a patient's quality of life, it is important to determine how often (eg, daily, weekly, monthly) episodes are occurring. More frequent episodes suggest significant abnormalities may be present.
•Amount – It is helpful to understand if patients are experiencing a small stain on their undergarments, a moderate amount of stool but not a full bowel movement, or a full bowel movement. Larger amounts of leakage may indicate a more severe defect in the continence mechanism.
•Type of leakage – It is helpful to ascertain solid versus liquid leakage; solid leakage generally indicates more severe sphincter weakness than liquid leakage.
•Pattern – We specifically ask about nocturnal episodes of fecal incontinence. Nocturnal incontinence is uncommon and is suggestive of an underlying structural bowel disorder or diabetes mellitus [38,39].
•Associated symptoms – If the patient has diarrhea or constipation associated with their symptoms, addressing the stool consistency can resolve the incontinence. Patients with baseline constipation or hard stools may have a fecal impaction as the etiology of their incontinence.
The patient should also be asked if tissue ever protrudes from the anal canal to suggest the presence of hemorrhoidal disease or a rectal prolapse; these are potential causes of incontinence.
Alarm findings — Alarm findings that warrant expedited evaluation include symptoms suggestive of an acute neurologic process, and those suggestive of colorectal malignancy.
●Features suggestive of an acute neurologic process (eg, spinal cord lesion, cauda equina syndrome) usually warrant urgent neuroimaging. Symptoms that should raise concern for a neurologic process include:
•Sudden onset incontinence without a corresponding change in bowel habits
•Low back or perineal pain
•Motor or sensory symptoms in the lower extremities
•Urinary incontinence
Patients with progressive symptoms or in whom there is a high suspicion for an acute neurologic process warrant urgent evaluation.
●Features suggestive of malignancy warrant an expedited referral to a gastroenterologist for colonoscopy (see "Clinical presentation, diagnosis, and staging of colorectal cancer"). Symptoms that raise concern for malignancy include:
•Unintentional weight loss
•Hematochezia or melena
•Rectal pain or tenesmus
Modifiable factors — As described above, most fecal incontinence is multifactorial. We elicit any modifiable factors that may be contributing.
History of constipation — We ask patients about prior history of constipation including frequency of bowel movements, as well as previous medications used to treat constipation. A history of significant constipation, particularly if not adequately treated, may suggest the presence of fecal impaction.
Medications — We specifically ask patients about medications that may be contributing to fecal incontinence. Common medications that can contribute include laxatives, muscle relaxants, magnesium supplements, and glucagon-like peptide 1 (GLP-1)-based therapies. In addition, anticholinergic agents, antidepressants, and antipsychotics can cause constipation and subsequent fecal impaction with overflow incontinence.
Dietary factors — We ask patients about dietary factors that may be contributing to fecal incontinence, including coffee consumption, use of sorbitol containing products (eg, sugarless gum), and lactose-containing foods and beverages. Large amounts of fructose from fruit can also contribute to fecal incontinence. In some cases, a food and symptom journal can be helpful to help identify dietary factors that are triggering incontinence.
Additional predisposing factors — We ask about additional predisposing risk factors that may be contributing to fecal incontinence.
●Prior childbirth or anorectal surgery – We ask patients about the number of vaginal deliveries, prolonged labor, the use of forceps, and perineal laceration. We also ask about prior anorectal surgery or pelvic irradiation. (See "Fecal and anal incontinence associated with pregnancy and childbirth: Counseling, evaluation, and management".)
●Comorbid medical conditions – We review whether the patient already has an established diagnosis of a predisposing comorbidity (eg, diabetes or Parkinson disease). For patients without an established diagnosis, we inquire about symptoms that might indicate these conditions. (See 'Medical conditions' above.)
Impact on quality of life — We ask patients with fecal incontinence about the impact this has had on their quality of life and mood. Fecal incontinence is associated with mood symptoms, including depression and anxiety, and can contribute to the loss of the ability to live independently [40-42]. Although some fecal incontinence specific quality of life scores have been studied, they are rarely used clinically [43].
Physical examination — The physical examination should include inspection of the perianal area, elicitation of the anal wink, and digital rectal examination (table 2).
●Inspection of perianal area – Inspection of the perianal area may reveal chemical dermatitis, suggesting chronic incontinence, a fistula, prolapsing hemorrhoids, or rectal prolapse. We examine the perineum both at rest and when bearing down.
●Anal wink sign – Perianal sensation should be tested by evoking the anocutaneous reflex (anal wink sign). The absence of this reflex suggests nerve damage and interruption of the spinal arc.
This is done with a cotton swab by gently stroking the perianal skin towards the anus and observing a reflexive contraction of the external anal sphincter [44]. An anal wink should be elicited bilaterally.
●Digital rectal examination – Digital rectal examination should be performed to detect anal pathology, such as a mass or fecal impaction. In addition, anal tone should be assessed during rest, with voluntary squeeze, and during simulated defecation. After consent is obtained, patients should be instructed to bear down and then to squeeze against the finger, which permits assessment of the movement and angle of the puborectalis muscle, pelvic floor descent, and squeeze pressure [45,46]. Weakness of the anal tone at rest indicates a defect in the internal anal sphincter, whereas weak squeeze pressure with normal contraction of the puborectalis suggests external anal sphincter weakness.
Endoscopy for most patients — Most patients with fecal incontinence warrant lower endoscopy. Exceptions are patients with a short duration of incontinence symptoms that occur in the setting of a change in stool consistency (eg, diarrheal illness or laxative use) and resolve with the resolution of diarrhea.
Choice of endoscopy study varies based on patient age, presence of alarm symptoms or chronic diarrhea, and history of prior examinations:
●In patients who are <45 years old, do not have alarm symptoms or chronic diarrhea, and are at average risk for colon cancer, we perform a flexible sigmoidoscopy to exclude mucosal inflammation or masses.
●In patients ≥45 years and in those with alarm features, persistent or unexplained chronic diarrhea, or risk factors for colorectal cancer or inflammatory bowel disease, we perform a colonoscopy. In patients with unexplained diarrhea, we obtain random colon biopsies to exclude microscopic colitis.
We generally try to perform endoscopy within several months for most patients; however, we expedite evaluation for those with alarm features concerning for colorectal malignancy.
There is no firm guidance regarding repeating testing in those who recently had a normal colonoscopy with adequate preparation. In general, if a patient with new fecal incontinence has had a colonoscopy within the previous six to 12 months, their symptoms are mild, and they have clear risk factors for incontinence, a repeat colonoscopy may not be necessary. In contrast, if symptoms are severe, do not respond to conservative treatment, or there is no clear etiology, a repeat colonoscopy is reasonable.
In patients who have had a colonoscopy after the onset of fecal incontinence and whose symptoms have been stable, we generally do not repeat endoscopy other than for routine colorectal cancer screening. (See "Screening for colorectal cancer: Strategies in patients at average risk" and "Screening for colorectal cancer in patients with a family history of colorectal cancer or advanced polyp".)
Limited role for laboratory studies — Laboratory studies are generally not helpful in the routine evaluation of fecal incontinence. In patients with associated diarrhea, we perform bloodwork and stool studies to determine the underlying etiology. The evaluation of patients with chronic diarrhea is discussed in detail elsewhere. (See "Approach to the adult with chronic diarrhea in resource-abundant settings", section on 'Initial evaluation'.)
SUBSEQUENT EVALUATION IN SELECTED PATIENTS
Persistent symptoms after initial treatment — In patients who do not respond to initial management, we perform anorectal manometry and imaging with either endorectal ultrasound or magnetic resonance imaging (MRI). Management is discussed elsewhere. (See "Fecal incontinence in adults: Management", section on 'Initial management'.)
We also perform this additional testing as part of the initial evaluation for patients who present with persistent symptoms that had sudden onset and no clear etiology.
This testing helps detect functional and structural abnormalities of the anal sphincters, the rectal wall, and the puborectalis muscle and provides a better understanding of the underlying pathophysiology that is needed to guide management.
Anorectal manometry — Anorectal manometry is helpful in the evaluation of fecal incontinence because it can diagnose functional sphincter weakness and detect abnormal rectal sensation, which is an important predictor of response to biofeedback training.
●Technique – During anorectal manometry, a catheter with pressure sensors is inserted into the rectum. Parameters that are measured include maximal resting anal pressure, amplitude and duration of squeeze pressure, the rectoanal inhibitory reflex, threshold of conscious rectal sensation, rectal compliance, and rectal and anal pressures during straining [47]. In addition, rectal sensation can be further assessed by inflating a rectal balloon to detect the threshold (smallest volume of rectal distension) for three common sensations: the first detectable sensation (rectal sensory threshold), the sensation of urgency to defecate, and the sensation of pain (maximum tolerable volume). (See "Overview of gastrointestinal motility testing", section on 'Anorectal manometry'.)
●Interpretation – Common findings on anorectal manometry and their interpretation include [48]:
•Decreased squeeze pressure suggests isolated external anal sphincter dysfunction. One common cause is episiotomy during childbirth; patients with this finding tend to respond well to biofeedback provided the external anal sphincter is still intact.
•Decreased resting anal pressure suggests injury to the internal anal sphincter complex or atrophy. Common causes include idiopathic atrophy or trauma (eg, surgical fissure removal) of the internal anal sphincter. Patients with this finding tend not to respond as well to anorectal biofeedback. Severe weakness of the external anal sphincter may indicate a rectal prolapse [49].
Endorectal ultrasound/magnetic resonance imaging — Endorectal ultrasound and MRI can detect structural abnormalities of the anal sphincters, the rectal wall, and the puborectalis muscle (image 1A-B) [25]. The internal sphincter is visualized more clearly by endoanal ultrasound, whereas MRI is superior for discriminating between an external anal sphincter tear and a scar and for identifying external sphincter atrophy [38].
Comparative data are limited, but ultrasound is generally preferred because it is less expensive and more widely available than MRI. In some institutions, endorectal ultrasound is completed during the same visit as anorectal manometry. (See "Endorectal endoscopic ultrasound (EUS) in the evaluation of fecal incontinence".)
Refractory symptoms — We perform defecography (barium defecography or MRI defecography) in patients with refractory fecal incontinence, especially if surgery is being considered. Defecography evaluates for muscle tears, length of the anal sphincter, anorectal angle, and pelvic descent [50]. Defecography can also detect abnormalities such as rectal prolapse or rectocele, although these findings may not be related to incontinence symptoms. The diagnosis and management of posterior vaginal defects (eg, rectocele) are discussed in detail elsewhere. (See "Posterior vaginal defects (eg, rectocele): Clinical manifestations, diagnosis, and nonsurgical management".)
Barium defecography is performed by instilling a barium paste into the rectum while, with the patient seated on a radiolucent commode, films are taken of the anorectal anatomy at rest and during straining and defecation. MRI defecography (also known as dynamic MRI imaging) has the advantage of better resolution of soft tissue surrounding the rectum and anal canal, better visualization of the anal sphincter and levator ani muscles with endoanal MRI, and avoidance of radiation. In contrast to barium defecography, which is performed in the seated position, MRI defecography is performed in the supine position [51,52].
Fecal impaction — We perform a balloon expulsion test in patients with fecal impaction and overflow fecal incontinence to identify dyssynergic defecation. (See "Etiology and evaluation of chronic constipation in adults", section on 'Assessment for a defecation disorder'.)
SOCIETY GUIDELINE LINKS —
Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Fecal incontinence".)
INFORMATION FOR PATIENTS —
UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient education: Fecal incontinence (The Basics)")
●Beyond the Basics topics (see "Patient education: Fecal incontinence (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Epidemiology – Prevalence estimates of fecal incontinence vary; approximately 14 percent of adults have had a previous episode of fecal incontinence, but less than 2 percent report chronic fecal incontinence. Risk factors include older age, diarrhea, fecal urgency, urinary incontinence, diabetes mellitus, central adiposity, and menopausal hormone therapy (See 'Epidemiology' above.).
●Pathophysiology – Normal defecation involves a complex sequence of events initiated by entry of stool into the rectum. Incontinence can occur due to altered stool consistency (eg, loose or liquid stools), decreased rectal compliance, alterations in rectal sensation, and anal sphincter dysfunction. Fecal incontinence is usually multifactorial due to multiple coexisting abnormalities (See 'Pathophysiology' above.)
●Etiologies – Fecal incontinence is usually a longstanding and slowly progressive condition.
•Sudden onset fecal incontinence is rare and usually occurs in the context of a diarrheal illness; other diagnostic considerations include anorectal trauma and neurologic conditions (eg, cauda equina). (See 'Sudden onset incontinence' above.)
•Chronic fecal incontinence is usually multifactorial . Common etiologies include prior childbirth or anorectal trauma, predisposing medical conditions (eg, inflammatory bowel disease, diabetes mellitus), and medications. Fecal impaction is a common cause of fecal incontinence in older adults. (See 'Chronic fecal incontinence' above.)
●Initial clinical evaluation – We obtain a detailed history and physical examination to evaluate for the etiology and identify additional contributors to fecal incontinence.
•Important aspects of the history include (table 1):
-Confirming true incontinence and characterizing duration, frequency, severity, and associated symptoms (eg, diarrhea). These characteristics may suggest potential underlying etiologies of the incontinence. (See 'Confirming and categorizing incontinence' above.)
-Assessing for alarm symptoms suggestive of an acute neurologic process (eg, sudden onset incontinence associated with new back pain or low extremity neurologic symptoms) or colorectal malignancy (eg, unintentional weight loss or rectal bleeding). These patients warrant expedited evaluation with imaging and/or endoscopy. (See 'Alarm findings' above.)
-Identifying factors that may be causing or contributing to fecal incontinence. Modifiable factors include a history of constipation, medications (eg, muscle relaxants), and dietary factors (eg, caffeine or sorbitol). We also identify major risk factors for fecal incontinence, including prior childbirth or anorectal trauma, and predisposing comorbid conditions (eg, diabetes mellitus). (See 'Modifiable factors' above and 'Additional predisposing factors' above.)
•During the physical examination, we examine the perianal area and assess the anocutaneous reflex. During digital rectal examination, we evaluate for masses and fecal impaction, and assess anal tone at rest, with voluntary squeeze, and during simulated defecation. (See 'Physical examination' above.)
●Endoscopy for most patients – Most patients with fecal incontinence warrant endoscopy. For patients who are ≥ 45 years old or who have alarm symptoms or chronic diarrhea, or at increased risk for colorectal cancer or inflammatory bowel disease, we perform a colonoscopy. For all others, we perform a flexible sigmoidoscopy. (See 'Endoscopy for most patients' above.)
●Subsequent testing for selected patients – For patients who do not respond to initial management, we perform anorectal manometry for functional evaluation and imaging (either with endorectal ultrasound or magnetic resonance imaging) for structural evaluation. We reserve defecography for those with refractory symptoms in whom surgery is being considered. (See 'Subsequent evaluation in selected patients' above.)
