Basics
Description
- Repeated unintentional soiling of underwear
- Most commonly associated with functional constipation with severe stool retention and subsequent overflow incontinence:
- 90% of cases of encopresis fall into this category.
- Another less common type of encopresis refers to the entity of repeated passage of feces into inappropriate places (usually clothing or floor) after the age of 4 years in the absence of constipation and structural or inflammatory diseases, also known as functional nonretentive fecal incontinence (FNRFI).
Epidemiology
- The reported ratio of boys to girls with encopresis ranges from 2:1 to 6:1.
- Boys are more likely to experience nonretentive fecal incontinence than girls at a ratio of 9:1.
- There is no association with family size, ordinal position in the family, age of parents, or socioeconomic status.
- Encopresis is reported in 1.5-2.8% of children >4 years of age.
- Between 10 and 30% of children with encopresis have nonretentive fecal incontinence.
Risk Factors
Genetics
Monozygotic twins have a 4-fold higher incidence than do dizygotic twins.
Alert
- Constipation with a rectal fecal mass is most common risk for encopresis.
- Children with FNRFI have more behavioral problems, poor self-esteem, and higher prevalence of attention deficit disorder.
Pathophysiology
Chronic constipation with fecal impaction results in overflow incontinence and reduced sensation secondary to rectal distention. The pattern of holding fecal matter, leading to chronic constipation and overflow incontinence, may result from a variety of causes, such as a painful experience from a fissure, difficult toilet training, or refusal to use school bathrooms. However, eliciting a medical history often does not reveal a triggering event.
Etiology
- Chronic constipation leads to a dilated rectum, decreased rectal sensation, shortening of the anal canal, and decreased anal sphincter tone in some patients.
- Findings on anorectal manometry include increased rectal sensory threshold and paradoxic contraction of the external anal sphincter during attempts at defecation (known as anismus).
- FNRFI occurs in children without constipation. The soiling may be a manifestation of an emotional disturbance, and it may be associated with specific triggers (person or place) or may represent an impulsive action triggered by unconscious anger. All studies in these patients are normal, including normal anorectal manometry and normal colonic transit times.
Commonly Associated Conditions
Enuresis is more frequently seen in patients with FNRFI (45% have daytime and 40% have nighttime enuresis) compared to constipated children.
Diagnosis
History
- Toileting habits:
- Constipation: frequency and size of bowel movements (large-diameter bowel movements are common in children with encopresis associated with functional constipation)
- Bowel movements that obstruct the toilet and/or chronic abdominal pain relieved by enemas or laxatives
- Retentive posturing: avoiding defecation by contraction of pelvic floor, squeezing the buttocks together (leg scissoring, crossing the legs, standing on tiptoes)
- Irritability, abdominal cramps, decreased appetite (symptoms improve after passage of large stool)
- Onset: Elicit history of triggering events (perianal infection, diet changes, toilet training, avoidance of school bathrooms, sexual abuse, or other stressful events).
- Enuresis (secondary daytime enuresis may occur in patients with megarectum compressing the bladder)
- Timing in the neonatal period of meconium passage, as well as past surgeries, medical history, and medications, are relevant.
- Unsteady or clumsy gait may suggest a neuromuscular disorder.
- Children with FNRFI do not have any history of constipation and have daily bowel movements. The incontinence is diurnal, usually in the afternoon.
Physical Exam
- Encopresis with functional constipation
- Fecal mass palpable in 40% of patients; fecal soiling in the perianal region
- Dilated rectum with a normally positioned anus
- Digital rectal exam is not recommended to routinely diagnose fecal impaction or FNRFI.
- Anal sphincter tone may be normal or slightly decreased; the anal canal is usually shorter than normal.
- Hard stool or a large amount of "mushy"¯ stool present in rectal vault
- FNRFI
- No palpable fecal mass
- Normal-size rectum
- Normal sphincter length
- Examine deep tendon reflexes, anal wink, rectal exam, lumbosacral spine exam to look for sacral dimpling, and documentation of normal growth.
- In patients with extreme fear of anal exam, attempt a perianal inspection and obtain a plain radiograph of the abdomen to establish a fecal impaction.
Diagnostic Tests & Interpretation
Referral to a pediatric gastroenterologist for further evaluation, including anorectal manometry, may be useful for patients who are not responding to standard management.
Lab
No tests are needed if both the history and physical exam are consistent with functional constipation and associated encopresis. If the patient's history or physical exam is atypical and a systemic disorder is suspected, appropriate diagnostic tests should be done.
Imaging
- Abdominal radiography is often necessary for patients who refuse a rectal exam, or when a rectal impaction is not palpable on abdominal exam (e.g., in obese patients).
- Enema with water-soluble contrast material can be both helpful diagnostically to look for areas of narrowing and therapeutically as a clean out procedure.
- MRI of the spine can be done for children with suspected spinal abnormalities. This is rarely necessary if the neurologic exam is normal.
- Colonic transit study with radio-opaque markers to confirm the patients' complaints or assess for slow transit constipation
Diagnostic Procedures/Other
- Rectal suction biopsy can be performed to evaluate for ganglion cells within the colonic mucosa and definitively evaluate for Hirschsprung disease.
- Anorectal manometry can be done in selected cases to evaluate anorectal function. The main indication is to demonstrate the rectoanal inhibitory reflex to exclude Hirschsprung disease and ultra-short-segment Hirschsprung disease. It may also show an increased threshold to rectal sensation, providing important information to the patient and the parents.
Differential Diagnosis
Determine whether stool leakage is caused by functional constipation or an underlying anatomic, metabolic, or neurologic abnormality. Fecal incontinence may be secondary to diarrheal diseases or defective neuromuscular control, such as in children with spinal defects.
- Neuromuscular
- Spinal cord tumor
- Tethered spinal cord
- Meningomyelocele
- Anal abnormalities:
- Anteriorly displaced anus
- Ectopic anus
- Inflammatory
- Proctitis (infectious or ulcerative)
- Fistula secondary to Crohn disease
- Celiac disease
- Stricture (after necrotizing enterocolitis or inflammatory bowel disease)
- Abdominal pelvic mass (sacral teratoma, meningomyelocele)
- Hypotonia (cerebral palsy, amyotonia congenita, familial visceral myopathy)
- Hirschsprung disease (constipation common, fecal incontinence rarely seen) or ultra-short-segment Hirschsprung disease
- Postsurgical repair of imperforate anus or Hirschsprung disease
- Endocrine
- Hypothyroidism
- Panhypopituitarism
- Diabetes mellitus
- Constipating drugs:
- Opiates
- Calcium supplements
- Psychotropics
Treatment
Medication
- Evidence suggests fecal disimpaction can be equally achieved with either oral PEG (with or without electrolytes at 1-1.5 g/kg/24 h) for 3-6 days of enemas or enema therapies. Sedated manual disimpaction is rarely required.
- Severe cases may require PEG ingestion by NG tube after disimpaction in a hospital setting.
- Stimulant laxatives:
- Magnesium citrate
- Bisacodyl
- Senna
- Oral stool softeners:
- PEG-3350 (0.75 mg/kg/24 h) is the preferred agent because of its palatability and ease of administration.
- Lactulose (2.5-10 mL/24 h for infants and 40-90 mL/day in older children) is recommended as the 1st-line treatment if PEG-3350 is not available.
- Milk of magnesia (0.5-1 mL/kg/24 h) is a good option.
- Mineral oil (5-20 mL in divided doses) may also be used in older children who have no risk of aspiration.
Issues for Referral
Patients with nonretentive fecal incontinence usually require referral to a mental health professional for more intensive behavioral intervention.
Complementary & Alternative Therapies
- Behavior modification therapy: decrease family stress. Have the child sit on toilet for defined amount of time (1 min/year of age to a maximum of 10 minutes) 1-2 times per day (ideally after a meal, tailored to the age of the child) and try to perform a Valsalva maneuver. Have young children blow into a pinwheel or a balloon to try to make them bear down.
- Use a sticker incentive chart if age-appropriate.
- Delay toilet training if the child is in diapers (to reduce stress).
- Motivate using positive reinforcement strategies. Biofeedback can be successful in some cases.
Inpatient Considerations
Initial Stabilization
Management combines pharmacology, behavioral modification, and dietary alterations.
Ongoing Care
Follow-up Recommendations
Patient Monitoring
- First follow-up visit is at 2 weeks to ensure compliance and success with the initial management.
- If the fecal impaction has been successfully removed, a reward system is started.
- The patient is followed at monthly intervals to ensure motivation and to be supportive.
- Treatment with stool softeners is needed until behavior and diet have improved and until rectal dilation has resolved.
- Medication is often needed for 6 months or longer.
Alert
- Parents may misconstrue stool-withholding behavior as an attempt to defecate.
- Parents may think that the soiling represents diarrheal illness, causing a delay in diagnosis and treatment.
- Parents may think their child's soiling is deliberate. They may not understand that the child can neither feel the passage of stool nor prevent it. The usual urge to defecate, which comes from stretching of the ampulla and internal anal sphincter, is not felt because the rectal ampulla is massively distended.
- Patients or their parents often stop stool softeners as soon as a normal stool pattern starts. If therapy has been ended prematurely, the patient's constipation and encopresis returns immediately because rectal tone is still poor and no other behavior or dietary modifications have been made.
Diet
- Normal fiber intake
- Adequate fluid intake
Complications
- Social problems
- UTIs, especially in girls
- Abdominal discomfort
- Decreased appetite and weight loss
Additional Reading
- Burgers RB, Benninga MA. Functional nonretentive fecal incontinence in children: a frustrating and long-lasting clinical entity. J Pediatr Gastroenterol Nutr. 2009;48(Suppl 2):S98-S100. [View Abstract]
- Desantis DJ, Leonard MP, Preston MA, et al. Effectiveness of biofeedback for dysfunctional elimination syndrome in pediatrics: a systematic review. J Pediatr Urol. 2011;7(3):342-348. [View Abstract]
- Di Lorenzo C, Benninga MA. Pathophysiology of pediatric fecal incontinence. Gastroenterology. 2004;126(Suppl 1):S33-S40. [View Abstract]
- Griffiths DM. The physiology of continence: idiopathic fecal constipation and soiling. Semin Pediatr Surg. 2002;11(2):67-74. [View Abstract]
- Har AF, Croffie JM. Encopresis. Pediatr Rev. 2010;31(9):368-374. [View Abstract]
- Tabbers MM, Dilorenzo C, Berger MY, et al. Evaluation and treatment of functional constipation in infants and children: evidence-based recommendations from ESPGHAN and NASPGHAN. J Pediatr Gastroenterol Nutr. 2014;58(2):265-281. [View Abstract]
Codes
ICD09
- 787.60 Full incontinence of feces
- 307.7 Encopresis
ICD10
- R15.9 Full incontinence of feces
- F98.1 Encopresis not due to a substance or known physiol condition
SNOMED
- 302690004 Encopresis (disorder)
- 302752001 Functional encopresis
- 73149003 Encopresis with constipation AND overflow incontinence (finding)
- 192025002 Non-organic discontinuous encopresis (finding)
FAQ
- Q: Is it possible to become "addicted"¯ to laxative medicines?
- A: Stool softeners, rather than cathartic laxatives or per rectal therapies are chosen for long-term therapy because the colon does not become dependent.
- Q: Will my child become sick if this problem is not resolved?
- A: Most children with chronic constipation and encopresis grow well and do not develop other health problems. The major problems are social and should be taken seriously. Social continence is crucial for the school-aged child.