Pediatric Constipation


Pediatric Constipation, Constipation in Children

  • Epidemiology
  1. Responsible for 3% of pediatric primary care visits (and 10-25% of pediatric gastroenterology visits)
  • Definition
  1. Decrease in stool frequency
    1. Fewer than 3 stools per week
  2. Decreased fluidity of Bowel Movements
    1. Most stools are hard, pebble-like or scybalous
  • Physiology
  1. See Defecation
  2. Mean stool frequency varies by age
    1. Breastfed infants under age 3 months: 2.9 stools/day (but healthy Breastfed infants may go days without a stool)
    2. Formula-fed infants under age 3 months: 2 stools/day
    3. Age 6 to 12 months: 1.8 stools per day
    4. Age 1 to 3 years: 1.4 stools per day
    5. Age over 3 years: 1.0 stools per day
  3. References
    1. Baker (1999) J Pediatr Gastroenterol Nutr 29:612-26 [PubMed]
  • Etiologies
  1. See Constipation Causes in Children
  2. See Constipation Causes in Newborns
  3. Functional Constipation (non-organic) causes are most common
    1. Often caused by stool witholding due to painful Bowel Movements
  • History
  1. Stool characteristics
    1. Time of passage of first meconium
      1. Delayed >48 hours in Hirschsprung's Disease
    2. Age of onset of stool problems
      1. Neonatal (especially under age 1 month) onset suggests congenital cause
      2. Onset under age 1 year suggests dietary cause
      3. Onset after 18 months suggests behavioral cause (Functional Constipation)
    3. Timing of stool problems
      1. Acute Constipation suggests organic cause
      2. Chronic Constipation suggests functional cause
      3. Older children will often have Colicky Abdominal Pain after eating in Functional Constipation
    4. Frequency of stools
      1. Infants without stool in 2 days or even up to 7 days may be normal pattern (especially in Breast fed infants)
      2. Normal stool frequency may suggest Irritable Bowel Syndrome
    5. Size of Bowel Movements
      1. Large caliber stools suggests functional cause (especially stool witholding)
      2. Small caliber stools suggest Hirschsprung's Disease
  2. Associated symptoms and conditions
    1. Abdominal Pain
      1. Relieved with Defecation may suggest Irritable Bowel Syndrome
      2. Exclude other causes of Abdominal Pain
    2. Presence of pain with Defecation
      1. Consider Anal Fissures (May also present with blood on stool)
    3. Presence of Rectal Prolapse
    4. Systemic symptoms (see red flags below)
      1. Suggests organic cause
  3. Bowel control
    1. Age of Toilet Training
    2. Presence of Encopresis or fecal soiling (suggests Fecal Impaction)
    3. Presence of Enuresis
    4. Stool withholding (see below)
  4. Prior and current management (medications, diagnostics)
    1. Review medication dosages to date
  5. Diet Diary (7 day history of foods and symptoms)
  6. Family History
    1. Constipation
    2. Hirschsprung's Disease
    3. Celiac Disease
    4. Cystic Fibrosis
    5. Thyroid disease
    6. Parathyroid disease
    7. Colon Cancer or Colonic Polyps
  7. Past medical and developmental history
  8. Psychosocial history (emotional stressors)
    1. May have triggered behavior change including stool witholding
  • History
  • Reassuring suggestive of functional cause
  1. Infrequent, hard, large-caliber stools
  2. Encopresis recurs after completing Toilet Training
  3. Pain on passing stool
  4. Perianal fissures (may causes blood on stool surface)
  5. Benign abdominal exam
  6. Stool witholding behaviors
    1. Child stiffens body to contract buttocks or anal sphincter
    2. Child hides in corner while stooling in diaper, crosses legs, rocks back and forth or fidgets with each urge to defecate
    3. Results in fecal stasis with hardening and enlarging of distal stool, that becomes more difficult to pass
    4. Ultimately stretches Rectum, decreases Defecation urge Sensation and results in Stool Incontinence
  • History
  • Red flag symptoms suggestive of organic cause
  1. See Hirschprung's Disease
  2. See Spinal Dysraphism
  3. No meconium by 48 hours old
    1. Hirschprung's Disease
    2. Cystic Fibrosis
    3. Congenital malformation of anorectum
    4. Spinal Dysraphism
  4. Failure to Thrive
    1. Hirschprung's Disease
    2. Malabsorption
    3. Cystic Fibrosis
    4. Metabolic disorder
  5. Abdominal Distention
    1. Hirschprung's Disease
    2. Fecal Impaction
    3. Pseudoobstruction or other neuroenteric condition
  6. Occult blood in stool
    1. Hirschprung's Disease
    2. Food Allergy
  7. Onset of Constipation symptoms under age 1 month
  8. Small-caliber stools
  9. Fever
  10. Bloody Diarrhea
  11. Bilious Vomiting
  12. Weight loss
  13. Abdominal Pain
  14. Nausea or Vomiting (especially Bilious Emesis)
  • Exam
  1. Growth evaluation for Growth Delay
    1. Malabsorption (Cystic Fibrosis, Celiac Disease)
  2. Abdominal exam
    1. Abdominal Distention
    2. Abdominal mass (Suprapubic fecal mass may be felt)
    3. Hepatomegaly or Splenomegaly
  3. Anal inspection
    1. Anterior anus
    2. Hemorrhoids
    3. Anal Fissures
  4. Rectal Examination
    1. Assessment of anal sphincter
    2. Retained stool
    3. Fecal Occult Blood Testing
  5. Back Inspection
    1. See Cutaneous Signs of Dysraphism
    2. Sacral sinuses or sacral hair tufts
  6. Neurologic Exam
    1. Lower extremity reflexes and Motor Exam
    2. Anal Wink
    3. Cremasteric Reflex
  1. Two or less Bowel Movements per week
  2. One or more Stool Incontinence episodes per week (after Toilet Training is complete)
  3. Excessive stool retention history
  4. Painful or hard Bowel Movement history
  5. Large rectal fecal mass
  6. Large diameter stools (may plug the toilet)
  • Diagnosis
  • Rome III Criteria for Functional Constipation >4 years old (at least 2 criteria present weekly for 2 months)
  1. Insufficient criteria for Irritable Bowel Syndrome
  2. Two or less Bowel Movements per week
  3. One or more Stool Incontinence episodes per week (after Toilet Training is complete)
  4. Excessive voluntary stool retention history (or retentive posturing)
  5. Painful or hard Bowel Movement history
  6. Large rectal fecal mass
  7. Large diameter stools (may plug the toilet)
  • Labs (consider if suggested by history)
  1. Thyroid Function Test
  2. Blood Urea Nitrogen
  3. Serum Electrolytes
  4. Serum Calcium
  5. Serum Magnesium
  6. Blood lead level
  7. Celiac panel (e.g. Tissue Transglutaminase)
  8. Sweat Test
  • Imaging (indicated for red flags above)
  1. Abdominal XRay (KUB)
    1. No benefit in Constipation (diagnosis is clinical)
      1. Berger (2012) J Pediatr 161(1):44-50 +PMID:22341242 [PubMed]
    2. Associated with increased risk of missing serious diagnosis (Intussusception, Appendicitis)
      1. Freedman (2014) J Pediatr 164(1): 83-8 +PMID:24128647 [PubMed]
  2. Unprepped Barium Enema Indications
    1. Suspected anatomic abnormalities
    2. Hirschsprung's Disease
    3. Colonic strictures from Necrotizing Enterocolitis
  3. Rectal manometry
    1. Hirschsprung's Disease
    2. Anismus
      1. Paradoxical external anal sphincter contraction
  4. Rectal suction biopsy by surgery
    1. Assess for Hirschsprung's Disease
  5. Transit study
    1. Administer radiopaque marker rings over 3 days
    2. Perform Abdominal XRAy (KUB) on third day
  6. Consider Spinal Dysraphism evaluation (L-Spine MRI)
  • Evaluation
  1. Initial evaluation in all patients
    1. Careful history and examination as above
    2. Consider Constipation in Children causes
  2. Red flag symptoms or signs present
    1. Pediatric Gastroenterology referral
    2. Diagnostic testing as directed by history
  3. No red flag symptoms or signs
    1. Empiric management for functional causes (see below)
    2. If no improvement with empiric therapy
      1. Consider Lab testing above
      2. Consider pediatric gastroenterology