encopresis

**Definition (DSM-5, elimination disorder):** Repeated passage of feces into inappropriate places (clothing or floor), voluntary or involuntary, at least once per month for ≥3 months, in a child with chronologic/developmental age ≥4 years. It is not attributable to a substance (e.g., laxatives) or a medical condition except via a constipation mechanism. Specifiers: with constipation and overflow incontinence (most common) or without constipation/overflow. The counterpart is enuresis (urine).

**Pathophysiology (retentive/overflow type):** - Child withholds stool because of painful defecation (hard stool, anal fissure), toilet-training conflict, fear of public toilets, or stressors. - Stool accumulates, causing fecal impaction and rectal distension. The rectum becomes dilated and the internal anal sphincter relaxes reflexively (rectoanal inhibitory reflex), while rectal sensation is blunted. - Liquid or soft stool leaks around the impacted mass, causing involuntary soiling. The child often is unaware of it. - This creates a vicious cycle: larger, harder stool leads to more pain, which leads to more withholding.

**Epidemiology:** About 1–3% of children, peaking at 5–7 years. Boys are affected more than girls (about 3–6:1). It often coexists with enuresis, UTIs (especially in girls), and behavioral problems.

**Clinical features:** Soiled underwear, a history of hard or infrequent stools, abdominal pain, and a palpable abdominal or suprapubic stool mass. Rectal exam may show a large stool-filled vault and a dilated rectum. Children may have secondary behavioral and social issues, such as shame, low self-esteem, and avoidance of peers.

**Differential and red flags (organic causes to exclude):** - Hirschsprung disease: delayed meconium passage (>48 h), failure to thrive, explosive stool on rectal exam, an empty rectal vault, and absent ganglion cells on rectal biopsy. Anorectal manometry shows absent RAIR. - Spinal cord anomalies (tethered cord, spina bifida occulta): sacral dimple or hair tuft, abnormal lower extremity neurologic findings, and absent anal wink. - Hypothyroidism, hypercalcemia, cystic fibrosis, celiac disease, and anorectal malformations. - Child sexual abuse: consider if there is a sudden change in toileting behavior or other signs of abuse.

**Management:** 1. Education and demystification, with a nonpunitive approach. Punishment worsens withholding. 2. **Disimpaction:** oral PEG 3350 high-dose, or enemas (e.g., sodium phosphate, mineral oil) in older children. Avoid sodium phosphate enemas in young children and in those with renal disease or Hirschsprung disease, because of the risk of electrolyte disturbance. 3. **Maintenance:** daily PEG 3350 (first line), with or without mineral oil, for months, plus a high-fiber diet and fluids. Stimulant laxatives such as senna or bisacodyl can be used as adjuncts. 4. **Behavioral:** scheduled toilet sits for 5–10 minutes after meals (using the gastrocolic reflex), a stool diary, and positive reinforcement and reward systems. 5. Biofeedback for dyssynergic defecation; psychotherapy if there are comorbid psychiatric problems. 6. Taper laxatives slowly. Relapse is common if they are stopped too soon.

**Boards pearls:** Encopresis is a child ≥4 years with soiling plus constipation, and overflow of liquid stool around impaction is the classic mechanism. First line is disimpaction followed by maintenance PEG with behavioral toilet training. It is not a sign of willful misbehavior. Do not confuse it with Hirschsprung disease, which presents early in life.