para>Some infants have only mild or intermittent constipation with intervening bouts of diarrhea. These patients typically have aganglionosis of a short segment of distal rectum. These cases may not be diagnosed until later in infancy or childhood.
EPIDEMIOLOGY
- Predominant age: infancy
- Predominant sex: males > females for short segment (4:1); males > females for long segment (5:4)
Incidence
- 1/2,000 to 5,000 births in the United States (white 91%, black 8%, Asian 0.5%)
- 2.8/10,000 live births in Asians (1)[B]
ETIOLOGY AND PATHOPHYSIOLOGY
- Congenital absence of Auerbach and Meissner autonomic plexuses in bowel wall (usually limited to the colon)
- Aganglionosis results in the lack of propagation of propulsive waves of muscle contraction and absence of relaxation of the internal anal sphincter.
- Obstruction may begin at anus and extend proximally to varying portions of the colon and small bowel.
Genetics
- Familial inheritance: 50 times base rate
- Associated with Down syndrome
- Dominant mutations in the RET gene are found in 50% of familial patients with Hirschsprung disease and in 15-35% of patients with sporadic Hirschsprung disease (10q11.2 locus) (1)[B].
RISK FACTORS
- Family history of Hirschsprung disease
- Offspring risk if parent has short segment is 2%; if parent has long segment, risk is up to 50%.
- Sibling risk if male affected: Female has 0.6% risk (short segment).
- Sibling risk if female affected: Male has 18% risk (long segment).
COMMONLY ASSOCIATED CONDITIONS
- Associated neurologic, cardiovascular, urologic, and gastrointestinal (GI) anomalies are found in 11-30% of patients (2)[C].
- Secondary aganglionic megacolon may be a late complication of Chagas disease.
- Down syndrome (four times expected incidence of Down syndrome in the normal population)
- Cardiovascular defects (6%)
- Urogenital anomalies (11%)
- Dandy-Walker; Waardenburg; Ondine; Sipple syndromes
- Cleft palate
- Congenital small or large bowel atresia
- Multiple endocrine neoplasia (MEN)-2B syndrome
- Prematurity
DIAGNOSIS
HISTORY
- Onset early in infancy; Newborn fails to pass meconium in 24 to 48 hours after birth (60-90% of infants with Hirschsprung disease).
- Obstipation
- May have diarrhea (usually intermittent)
- Constipation (should be thoroughly investigated in any child if present since birth)
- Diagnosis missed in older children and adults because it is considered a neonatal disease.
- Poor feeding habits
- Lack of physiologic urge to defecate (older children)
- Vomiting: bilious vomiting in 19-37% of children
- Abdominal distension
- 5-44% of children present with Hirschsprung-associated enterocolitis (3)[B]:
- Foul-smelling diarrhea, fever, and abdominal distension
- May progress to fatal toxic megacolon if untreated
PHYSICAL EXAM
- Early infancy
- Marked abdominal distention (63-91% of neonates with Hirschsprung)
- Visible colonic peristalsis
- Palpable fecal mass
- Growth retardation (possible)
- Older infants
- Failure to thrive
- Empty rectum on digital examination
- Palpable colon
- Visible peristalsis
- Explosive diarrhea with rectal exam
- 5-44% of children may present with Hirschsprung-associated enterocolitis (3)[B].
DIFFERENTIAL DIAGNOSIS
- Secondary megacolon (e.g., Chagas disease)
- Functional/acquired megacolon
- Functional constipation
- Hypoganglionosis
- Meconium plug syndrome
- Small left colon syndrome
- Meconium ileus
- Neuronal intestinal dysplasia
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
- Serum electrolytes
- Albumin
- CBC
- Thyroid function
- Plain abdominal radiograph
- Large ovoid fecal mass mottled by small, irregular gas shadows
- Fluid levels within proximal bowel loops
- Diaphragm may be elevated.
- Contrast enema, water soluble (unprepped): Identification of transition zone is useful in planning definitive operative procedure (4)[B]
- Dilation of sigmoid colon above narrowed distal sigmoid or rectum
- Narrowed portion of colon rippled or segmented
- Typical transition zone between narrowed distal colon and dilated proximal bowel
- Enema may be therapeutic for other diagnoses (meconium ileus/plug, small left colon syndrome).
Diagnostic Procedures/Other
- Suction aspiration biopsy of bowel wall (2 cm above dentate line): can be done without anesthesia at bedside (absence of ganglia in wall of narrowed rectum)
- Full-thickness biopsy may be required if suction biopsy is equivocal (most commonly needed in older infants/children who have thicker mucosa).
- Proctosigmoidoscopy: ampulla empty of feces (not often of value without biopsy)
- Laparoscopy: normal proximal colon dilated (not helpful without biopsy)
- Anorectal manometry: high baseline resting pressure and absent rectoanal inhibitory reflex (3)[B]
- Rectosphincteric reflex may not be present until after 14 days of age.
Test Interpretation
- Dilatation and hypertrophy of all layers proximal to involved colon (transition zone represents the transition from narrowed distal colon to dilated proximal bowel)
- Aganglionosis of involved bowel with submucosal hypertrophied nerve bundles on biopsy
- Calretinin and acetylcholinesterase stains may be helpful.
TREATMENT
GENERAL MEASURES
- Treatment may be symptomatic or definitive.
- Correct fluid and electrolyte imbalances.
- Abdominal decompression with a nasogastric tube
- Removal of fecal accumulation: retention enemas of 3 to 4 oz (90 to 120 mL) of mineral oil followed by repeated colonic irrigations with isotonic saline solution. Avoid use of other solutions (e.g., water, soap-sud enemas).
- Manual disimpaction for short-segment disease may be necessary.
MEDICATION
First Line
- Broad-spectrum IV antibiotics for patients presenting with enterocolitis (4)[A]
- Bowel prep prior to surgery
Second Line
Metronidazole (Flagyl) for bowel preparation
SURGERY/OTHER PROCEDURES
- Inpatient surgery
- Proximal colostomy and resection of aganglionic bowel is the gold standard (necessary when there is significant proximal dilatation).
- Definitive pull-through procedure (Duhamel, Soave, or Swenson) when dilatation has resolved (usually performed at 3 to 6 months) (2)[C].
- Single-stage procedure may be possible in infants.
- Transanal endorectal pull-through in infants if proximal bowel not too dilated (5)[C]; usually done without a protective colostomy.
- Transanal endorectal pull-through is associated with fewer complications and fewer episodes of enterocolitis when compared to transabdominal pull-through procedures (6,7)[A]:
- Laparoscopic technique may be used alone or combined with transanal endorectal pull-through.
- Confirmation of normal ganglion cells mandatory at colostomy and proximal resection sites prior to anastomosis
- Total-colon Hirschsprung disease may require other procedures, including Martin modification of Duhamel pull-through (5,8)[C]:
- Cecal patches may be used to facilitate water absorption in pulled-through small bowel.
- Total-bowel Hirschsprung disease (68 reported cases in world literature through 2009) (9)[B]
- Family history of Hirschsprung disease in 14.7%, RET gene mutation was identified in 71.4%, associated anomalies were found in 20.6%; 66.2% died before age 8 years
- Ultimately requires small bowel transplantation.
- Long (30 to 40 cm) myomectomy of proximal bowel and creation of proximal small bowel stoma (at 30 to 40 cm from ligament of Treitz) may allow small-volume feeding in some infants.
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
Early workup (ambulatory or in hospital, depending on the patient's condition)
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
- Postsurgical monitoring for fluid/electrolyte balance, protein-calorie nutrition and growth
- Long-term monitoring for continence and constipation
DIET
- Diet does not control obstipation.
- Postoperative diet: standard for age
PATIENT EDUCATION
- After surgery, instruct parents to detect and report dehydration, decreased urinary output, sunken eyes, poor skin turgor, vomiting, or fever.
- Parental bonding through maximal participation in their child's care, including colostomy care
- Request enterostomal therapist to teach family appropriate colostomy care.
- Daily anorectal dilations are frequently required following Soave or transanal endorectal pull-through procedures to prevent anastomotic stricture:
- May be required for several months
PROGNOSIS
- Favorable
- Mortality decreased over last 25 years, now estimated at ≤3% (2)[C]
- Requires long-term follow-up.
- Aggressive management of suspected enterocolitis:
- Rectal irrigation
- IV antibiotics
- Nasogastric decompression
COMPLICATIONS
- Toxic enterocolitis, possibly fatal
- The reported mortality from enterocolitis has decreased to <1% over the last 20 years (10)[B].
- Enterocolitis may occur before or after definitive pull-through:
- 5-42% of postoperative patients
- The rate of enterocolitis may be less after transanal pull-through compared with other procedures (10)[B].
- Enterocolitis may be rapidly progressive.
- Diagnostic features are abdominal distension, lethargy, bilious emesis, and diarrhea.
- Treated with nasogastric decompression, IV hydration, IV antibiotics, and colonic washouts
- Bleeding and/or perforation
- Anal stenosis at anastomotic site (0-35%)
- Stricture is associated with higher risk of postoperative enterocolitis (3)[B].
- Anastomotic leak in 1-10%
- Cuff abscess in 5%
- Perineal excoriation is common (usually improves within 2 to 3 months).
- Wound infection in 4% and dehiscence in 1%
- Fecal incontinence in 1-39% (3)[B]
- Enuresis in 5-26%
- Late mortality in 0.7-5% (3)[B]
- Obstructive complications (9)[C]
- Mechanical obstruction from twisting of pulled-through bowel and intra-abdominal adhesions
- Secondary aganglionosis related to ischemia of pulled-through bowel
- Motility disorder involving the proximal bowel (containing ganglion cells)
- Internal sphincter achalasia (all children with Hirschsprung disease lack the normal rectoanal inhibitory reflex): The inability to relax the internal anal sphincter which typically improves over time.
REFERENCES
11 Tam PK, Garcia-Barcel ³ M. Genetic basis of Hirschsprung's disease. Pediatr Surg Int. 2009;25(7):543-558.22 Suita S, Taguchi T, Ieiri S, et al. Hirschsprung's disease in Japan: analysis of 3852 patients based on a nationwide survey in 30 years. J Pediatr Surg. 2005;40(1):197-201; discussion 201-202.33 Haricharan RN, Georgeson KE. Hirschsprung disease. Semin Pediatr Surg. 2008;17(4):266-275.44 Langer JC. Hirschsprung disease. Curr Opin Pediatr. 2013;25(3):368-374.55 Wildhaber BE, Teitelbaum DH, Coran AG. Total colonic Hirschsprung's disease: a 28-year experience. J Pediatr Surg. 2005;40(1):203-206; discussion 206-207.66 Kim AC, Langer JC, Pastor AC, et al. Endorectal pull-through for Hirschsprung's disease-a multicenter, long-term comparison of results: transanal vs transabdominal approach. J Pediatr Surg. 2010;45(6):1213-1220.77 Gosemann JH, Friedmacher F, Ure B, et al. Open versus transanal pull-through for Hirschsprung disease: a systematic review of long-term outcome. Eur J Pediatr Surg. 2013;23(2):94-102.88 Laughlin DM, Friedmacher F, Puri P. Total colonic aganglionosis: a systematic review and meta-analysis of long-term clinical outcome. Pediatr Surg Int. 2012;28(8):773-779.99 Ruttenstock E, Puri P. A meta-analysis of clinical outcome in patients with total intestinal aganglionosis. Pediatr Surg Int. 2009;25(10):833-839.1010 Ruttenstock E, Puri P. Systematic review and meta-analysis of enterocolitis after one-stage transanal pull-through procedure for Hirschsprung's disease. Pediatr Surg Int. 2010;26(11):1101-1105.
ADDITIONAL READING
De La Torre L, Langer JC. Transanal endorectal pull-through for Hirschsprung disease: technique, controversies, pearls, pitfalls, and an organized approach to the management of postoperative obstructive symptoms. Semin Pediatr Surg. 2010;19(2):96-106.
SEE ALSO
Constipation
CODES
ICD10
Q43.1 Hirschsprungs disease
ICD9
751.3 Hirschsprungs disease and other congenital functional disorders of colon
SNOMED
- Hirschsprungs disease (disorder)
- Congenital dilatation of colon (disorder)
- Long segment Hirschsprung's disease (disorder)
- Short segment Hirschsprung's disease (disorder)
CLINICAL PEARLS
- All infants with primary constipation must be evaluated for Hirschsprung disease.
- Early diagnosis helps prevent toxic enterocolitis.
- An unprepped barium enema followed by a suction rectal biopsy confirms the diagnosis of Hirschsprung disease.