Good Morning! Tuesday, April 3 rd 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 visits 25% of referrals to pediatric GI Definition: ◦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 1 st 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 stool Longer the stool remains in rectum, more water is removed, harder the stool becomes to point of impaction

Functional Constipation Accounts for 95% of cases Persistent, difficult, infrequent, or incomplete defecation without evidence of anatomic or biochemical cause Peaks in pre-school years 3 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◦A. Begin evaluation for immunodeficiency ◦B◦B. Perform renal scintigraphy ◦C◦C. Prescribe stool softener and regular bowel routine ◦D◦D. Prescribe oral oxybutynin ◦E◦E. Refer to pediatric nephrologist

History Passage of meconium Transitions: breastmilk to formula to cow’s milk; child care to all-day school; diapers to toilet training Family history Character of stools Encopresis Past medical history Medications *Urinary incontinence

Physical Exam Growth and weight gain Umbilical girth Abdominal exam ◦Bowel sounds ◦Palpable dilated loops Rectal exam ◦Distended rectum full of stool Back (look for sacral skin findings)

Laboratory Plain abdominal radiograph Thyroid function, electrolyte levels, magnesium *UA, urine culture Lumbosacral spine films/MRI Barium enema Lead level Motility 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 1 st week of life Delayed passage of meconium (after 48 hours) Abdominal distention Vomiting Transition zone on enema Failure to thrive Acute enterocolitis 60% diagnosed by 3 months of age Absence 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 5 90% 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

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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 vegetables Probiotics ◦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%