Good Morning!Tuesday, April 3rd 2012
Causes of Constipation
Nonorganic
Functional fecal retention
Anatomic
Anal stenosis
Imperforate anus
Anteriorly displaced anus
Intestinal stricture (post NEC)
Abnormal musculature
Prune-belly
Gastroschisis
Down syndrome
Intestinal Nerve/Muscle Abnormalities
Hirschsprung disease
Pseudo-obstruction
Intestinal neuronal dysplasia
Spinal Cord Defects
Tethered Cord
Spinal cord trauma
Spina bifida
Causes of Constipation
Drugs
Anticholinergics
Narcotics
Antidepressents
Chemotherapy
Pancreatic enzymes
Lead
Vitamin D intoxication
Metabolic Disorders
Hypokalemia
Hypercalcemia
Hypothyroidism
Diabetes Mellitus
Intestinal Disorders
Celiac disease
Cow’s milk protein intolerance
Cystic fibrosis
Inflammatory bowel disease
Tumor
Connective Tissue Disorders
SLE
Scleroderma
Psychiatric Disorders
Anorexia nervosa
Constipation
5% of all outpatient pediatric visits25% of referrals to pediatric GIDefinition:
◦Infrequent bowel evacuation◦Hard small feces◦Difficult or painful evacuation of large-diamter
stools◦Fecal incontinence (encopresis)
Its all relative◦A child with 3 small stools a day may not have
evacuated colon, but a child with 2 large soft stools a week is not constipated
Normal Stooling Patterns
90% of newborns pass meconium in 1st 24 hours
Intestinal transit time◦8 hours = 1 month◦16 hours = 2 years◦26 hours = 10 years
Infant dyschezia◦10 minutes of straining and crying before
successful passage of soft stool in otherwise healthy infant; failure of pelvic floor to relax; resolves spontaneously
Vicious cycle of constipation
Repetitive denial of evacuation due to pain leads to stretching of rectum and lower colon
Reduction in muscle tone Retention of stoolLonger the stool remains in rectum, more
water is removed, harder the stool becomes to point of impaction
Functional Constipation
Accounts for 95% of casesPersistent, difficult, infrequent, or
incomplete defecation without evidence of anatomic or biochemical cause
Peaks in pre-school years3 periods prone to constipation:
◦Introduction of cereals and solid foods◦Toilet training◦Start of school
Functional Constipation (cont’d)
Toddlers and older children may withhold stool:◦Painful defecation◦Avoid defecation in a strange toilet away from
home◦Too distracted (ADHD)
Symptoms:◦Early satiety, desire to eat small volumes all
day, increasing irritability, spasms of abdominal pain in lower abdomen
Question
A 5-year-old girl has a confirmed urinary tract infection. She has had 4 UTIs in the past 2 years, which all resolved with antibiotics. She denies urgency and frequency. The only significant history is constipation. Renal U/S and VCUG are normal. Her growth is normal. You prescribe Bactrim.
Of the following, the MOST appropriate additional step to reduce future UTIs is:◦ A. Begin evaluation for immunodeficiency◦ B. Perform renal scintigraphy◦ C. Prescribe stool softener and regular bowel routine◦ D. Prescribe oral oxybutynin◦ E. Refer to pediatric nephrologist
History
Passage of meconiumTransitions: breastmilk to formula to cow’s
milk; child care to all-day school; diapers to toilet training
Family historyCharacter of stoolsEncopresisPast medical historyMedications*Urinary incontinence
Physical Exam
Growth and weight gainUmbilical girthAbdominal exam
◦Bowel sounds◦Palpable dilated loops
Rectal exam◦Distended rectum full of stool
Back (look for sacral skin findings)
Laboratory
Plain abdominal radiographThyroid function, electrolyte levels, magnesium*UA, urine cultureLumbosacral spine films/MRIBarium enemaLead levelMotility testing
◦Colon transit studies◦Anorectal manometry◦Consider in pts. with no organic cause of
constipation, but failure to respond to aggressive treatment
*Hirschsrung Disease
Lack of ganglion cells in the myenteric and submucosal plexus of bowel wall
Onset of symptoms in 1st week of lifeDelayed passage of meconium (after 48
hours)Abdominal distentionVomitingTransition zone on enemaFailure to thriveAcute enterocolitis60% diagnosed by 3 months of ageAbsence of encopresis
Hirschsprung Disease
Encopresis
Repeated involuntary fecal soiling in the underpants
Children should obtain fecal continence by the age of 4◦*Encopresis is a symptom rather than a
developmental variation after age 4 to 590% is functional
◦Retentive constipation with overflow incontinence
*5 to 10% is organic, behavioral, environmental (privacy issues)◦Anatomic, neurologic, metabolic, iatrogenic
Management of Chronic Constipation and Encopresis
Phase 1: Disimpaction
Management of Chronic Constipation and Encopresis
Phase 2: Maintenance◦Pattern of daily defecation should be maintained◦The goal is to maintain soft bowel movements
once or twice a day◦This phase can last from 2 to 6 months or longer
Months are required for rectum to return to normal caliber and regain normal sensation
◦*Best approach is a combination of medical therapy, behavioral modification, and counseling
*
Management of Chronic Constipation and Encopresis
Behavior modification◦Patient should sit on
toilet for 10 minutes after meals 2-3 times/day
◦A footstool may be used to help improve the Valsalva maneuver
◦“Star” charts
Behavior Modification
Anorectal dyssynergia◦Paradoxic increase in external sphincter tone
while trying to defecate◦Diagnosed with anorectal manometry◦Patients are candidates for biofeedback therapy
with manometry
Management of Chronic Constipation and Encopresis
Phase 3: Weaning From Medication◦Start when child consistently is achieving 1 to 2
soft bowel movements daily◦Usually after 6 months◦Wean stimulant laxatives first, then lubricant or
osmotic agents
Management of Chronic Constipation and Encopresis
Diet◦High-fiber diet
Shown to increase number of bowel movements and decrease episodes of encopresis
Avoid until child is no longer withholding stool, because bulking with fiber may lead to additional withholding
Whole grains, fruits, and vegetablesProbiotics
◦Have been shown to improve colonic transit time◦More studies are needed
Relapse
Patients who show no improvement after 6 months should be referred to GI
*Relapses are common! Rates of recurrence approach 50%