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Hirschsprung's DiseaseAka: Hirschprung's Disease, Congenital Aganglionic Megacolon, Congenital Megacolon, Aganglionosis
- Definition
- Enteric dysganglionosis condition
- See Also
- Epidiomology
- Incidence: 1 in 5000 to 8,000 live births
- Male to female ratio: 3:1 or 4:1
- Causes
- Genetic (Family History in 3-7% of cases)
- RET-proto-oncogene (Chromosome 10q11.2) related
- Associated with Multiple Endocrine Neoplasia IIa
- Increased risk with affected sibling
- Boys with sibling affected: 3-5%
- Girls with sibling affected: 1%
- Cild's sibling with entire colon affected: >12%
- Environmental factors
- Intrauterine Intestinal Ischemia or infections
- Genetic (Family History in 3-7% of cases)
- Pathophysiology
- Ganglion cells absent from part or all of the colon
- Lack of intramural ganglionic cells
- Submucosa level (Meissner's Plexus)
- Myenteric level (Auerbach's Plexus)
- Aganglionic region begins at anus, extends proximally
- Distance proximal to Pectinate Line exceeds 4 cm
- Involved distal colon fails to relax
- Results in progressive Functional Constipation
- Lack of intramural ganglionic cells
- Congenital defect at 4-12 weeks gestation
- Neuroblast migration interrupted
- Ganglion cells fail to migrate via neural crest
- Lack of innervation
- Hypertonic bowel results in functional stenosis
- Partial or complete colonic obstruction
- Proximal intestine markedly dilated with feces, gas
- Ganglion cells absent from part or all of the colon
- Types
- Short-segment Hirschprung's Disease
- Limited to rectosigmoid colon
- More mild than long segment disease
- Diagnosis may be delayed into early childhood
- Long-segment Hirschprung's Disease
- Involves regions proximal to rectosigmoid
- In the most severe cases, may involve entire colon
- Short-segment Hirschprung's Disease
- Associated Conditions
- Bladder diveticulum
- Congenital deafness
- Cryptorchidism
- Down's Syndrome
- Hydrocephalus
- Imperforate anus
- Meckel's Diverticulum
- Neuroblastoma
- Primary Alveolar Hypoventilation (Ondine's Curse)
- Renal agenesis
- Ventricular Septal Defect
- Waardenburg's Syndrome
- Pheochromocytoma
- Meningomyelocele
- Presentations: Age
- Early: Newborn
- No meconium in 24-48 hours of birth (90% of cases)
- First month of life
- Progressive abdominal distention
- Small caliber stools (pencil-thin)
- Infrequent, explosive Bowel Movements
- Failure to Thrive due to poor feeding
- Bilious Emesis
- Jaundice
- Two to three months of life
- Enterocolitis (fever, explosive bloody Diarrhea)
- Initial presentation in one third of patients
- Enterocolitis (fever, explosive bloody Diarrhea)
- Older Childhood
- Chronic progressive Constipation
- Failure to Thrive or malnutrition
- Fecal Impaction
- Abdominal distention
- Recurrent despite enemas, Laxatives, feeding changes
- Early: Newborn
- Presentation Patterns
- Presentation soon after birth
- Complete Obstruction
- Emesis
- Failure to Pass Meconium in first 24 hours (90%)
- Repeated Bowel Obstruction
- Emesis
- Dehydration
- Delayed meconium passage
- Persistent mild Constipation
- Suddenly develops obstruction
- Distention
- Emesis
- Diarrhea followed by obstruction
- Fever
- Enterocolitis
- Persistent mild Constipation
- Never completely obstructs
- Presentation soon after birth
- Signs
- Distended abdomen
- Palpable loops of bowel
- Rectal exam
- Tight anal sphincter
- Rectal exam without stool in ampulla
- Explosive release of feces and flatus may follow exam
- Imaging
- Abdominal XRay
- Massive colon distention with gas and feces
- Air-fluid levels may be present
- Air in bowel wall suggests enterocolitis
- Non-prepped Barium Enema
- Contraindicated if enterocolitis suspected
- False negative tests are common
- Dilated colon proximal to aganglionic region
- Spastic transitional segment
- Irregular saw-toothed outline
- May be best seen on lateral view
- Barium may be retained in proximal bowel >24 hours
- Abdominal XRay
- Diagnostics
- Anal manometry
- Shows lack of internal anal sphincter relaxation
- Involves internal anal sphincter on rectal distention
- Rectal suction biopsy (>1.5 cm above Dentate Line)
- Absence of Meissner, Auerbach's ganglion plexuses
- Marked hypertrophy of nerve trunks
- Anal manometry
- Differential Diagnosis
- See Neonatal Constipation Causes
- See Failure to Pass Meconium
- Functional Constipation
- Onset at over age 12 months
- Meconium passed in first 24 hours of life
- Normal growth
- Normal rectal exam
- Management
- Pre-surgery maintenance
- Serial rectal irrigation decreases bowel distention
- Surgery
- Mild to moderate cases (e.g. short-segment disease)
- Ilioanal pull-through anastomsis
- Severe cases (e.g. enterocolitis)
- Colostomy for 6 months and then ileoanal procedure
- Mild to moderate cases (e.g. short-segment disease)
- Post-Surgery
- Maintain high Dietary Fiber
- Monitor for enterocolitis despite surgery
- Pre-surgery maintenance
- Complications
- Untreated
- Bowel rupture
- Enterocolitis (up to 50% of cases)
- May occur 2-10 years after surgery
- Post-Surgical
- Constipation (10%)
- Fecal Incontinence (1%)
- Untreated
- Prognosis
- Early diagnosis results in best prognosis
- Before surgery (without recognition and treatment)
- Mortality: 50%
- After surgery
- Early complications: 30%
- Late complications: 39%
- Mortality: 2.4%
- Increased in Down's Syndrome
- Increased in child under age 4 months
- Increased if postoperative obstruction
- Permanent ileostomy: 0.8%
- Permanent colostomy: 0.5%
- References
Congenital Megacolon (C0019569) | |
|---|---|
| Definition (MSH) | Congenital MEGACOLON resulting from the absence of ganglion cells (aganglionosis) in a distal segment of the LARGE INTESTINE. The aganglionic segment is permanently contracted thus causing dilatation proximal to it. In most cases, the aganglionic segment is within the RECTUM and SIGMOID COLON. |
| Definition (CSP) | abnormally large or dilated colon due to congenital absence of myenteric ganglion cells in a distal segment of the large bowel; resultant loss of motor function in this segment causes massive hypertrophic dilatation of the normal proximal colon; condition appears soon after birth; called also Hirschsprung's disease, aganglionic megacolon and pelvirectal achalasia. |
| Concepts | Congenital Abnormality (T019) |
| ICD9 | 751.3 |
| English | aganglionic megacolon, Aganglionosis, CONGEN MEGACOLON, Congenital aganglionic megacolon, Congenital Megacolon, HIRSCHSPRUNG DIS, Hirschsprung Disease, HIRSCHSPRUNG DISEASE 1, Hirschsprung's Disease, HIRSCHSPRUNGS DIS, Hirschsprungs Disease, HSCR, HSCR1, Macrocolon, MEGACOLON CONGEN, MEGACOLON CONGENITAL, MGC, pelvirectal achalasia |
| Spanish | aganglionosis, enfermedad de Hirschprung, enfermedad de Hirschsprung, macrocolon, megacolon aganglionar, megacolon aganglionar congénito, megacolon aganglionar congenito, megacolon congénito, megacolon congenito |
| Credits | Derived from the NIH UMLS (Unified Medical Language System) |
