Hirschsprung's diseaseBY

RAMKUMAR

• Hirschsprung’s disease is the most common cause of lower intestinal obstruction in neonates.

• Hirschsprung’s disease (aganglionic megacolon) is a congenital anomaly caused by migratory failure of neural crest cells leading to abnormal innervations of the bowel.

• The defect begins in the internal anal sphincter and extends proximally for a variable length of gut

INTRODUCTION

INCIDENCE: 1\5000 live birth newborn

70-80% is boys. (M / F. 4: 1 )

Less common in blacks.

EPIDEMIOLOGY

The fundamental pathology in HD is the absence of ganglion cells in the submucosal and intermuscular nerve plexuses and is associated with an increase in the nerve fibers in the affected segment .

That aganglionic segment usually involves the terminal intestine, i.e. the rectum or rectosigmoid. The aganglionic segment may, however, include the entire large bowel and even small bowel..

PATHOPHYSIOLOGY

The colon proximal to the aganglionic segment, in an effort to overcome the partial obstruction, becomes distended and its wall markedly thickened because of muscle hypertrophy

The degree of hypertrophy and dilatation depends upon the duration and degree of obstruction and thus, indirectly to the age of the patient.

PATHOPHYSIOLOGY

1. Congenital : This type is the commonest one . Etiology of the disease is still unknown.but Genetic factors are

now identified. 10% of cases have familial history, especially those with long

segment disease.2. Acquired :

Degeneration of the ganglions may occur due to:-Vascular causes like after pullthrough procedure due to

ischemia & tension. - Non vascular causes like

Trypanosoma (chaga's disease). Vit B1 def. Chronic infection ( TB.).

TYPES

HD is usually a solitary anomaly in a full term, otherwise healthy infant

Associated anomalies do occur in nearly 20% of cases urogenital system (11%) cardiovascular system (6%) gastrointestinal system (6%), with 8% having various other malformations

Prematurity is reported in as many as 10% of those children with HD Trisomy 21 occurs in approximately 5% of cases

ASSOCIATED ANOMALY

1. Failure to pass meconium in the 1st 24h of life

98% of neonates pass meconium in the first 24 hours of age.. Any newborn who fails to pass meconium in the first 24-48 hours of life should be evaluated for possible Hirschsprung's disease.

2. Neonatal Intestinal obstruction symptoms include bilious vomiting, abdominal

distension and refusal to feed.3. Recurrent Enterocolitis mainly in the 1st three months of life.

CLINICAL FEATURES

4. TOXIC MEGACOLON : Fever. Abdominal distension. Bile stained vomitous. Explosive diarrhoea. Dehydration. Shock.

5. Spontanous perforation occurs in 3%,specially if long segment aganglionosis.

6. Chronic constipation patients may have chronic constipation in response to changes in feeding. And may have Growth retardation. Multiple fecal masses on abdominal examination.

CLINICAL FEATURES

History failure to pass meconium, painless

abdomenal distension & constipation) Physical examinations Distended abdomen with Multiple fecal

masses on abdominal examination on DRE characteristically there is

Anal sphincter is hypertonic Rectum is typically empty. Hard fecal mass.

DIAGNOSIS

Radiology 1. Plain x-rays of the abdomen :Erect & supine2. Contrast Enema. Shows narrow distal segment,funnel-shaped

dilatation at level of transition zone with marked dilatation of the proximal colon.

24-hrs delayed films is important in diagnosis; it shows poor emptying with barium throughout the colon, as opposed to the child with psychogenic stool holding in whom the barium generally collects in the distal rectosigmoid.

DIAGNOSIS

Rectal biopsy : Rectal biopsy is the definitive

diagnostic test and demonstrates absence of ganglion cells, nerve hypertrophy and stains indicating increased acetylcholinesterase activity.

suction mucosal biopsy (at different levels ). Can be done without anesthesia

full thickness biopsy is done under general anesthesia.

DIAGNOSIS

Electromanometry : not useful in neonate excellent screening tool in infant &

children . The classic finding is the absence of

the recto anal inhibitory reflex when the rectum is distended.

A balloon is inflated in the rectum to measure pressure in the area

UltraSonography: for associated anomalies

DIAGNOSIS

Treatment: Decompression: introduce a rectal tube and

irrigation Colostomy Definitive procedures Closing of the stoma

Chronic constipation : laxative saline enema. Work up to establish the diagnosis then the definitive treatment will be planned

Open surgery : There are many surgical options for Pull-

through operation. All aiming at resection of aganglionic segment and anastomosing the two normal ganglionic ends. They give excellent result in 90%.

a.swenson.b.soave. c.Rehbein.d. Duhamel.e. Boley's

TreatmentTransanal Endorectal Pull-Trough It can be performed safely in infant as well Generally one-stage surgery No abdominal phase The anastomosis is happening in a „safe”

place at the pectinate line

Hirschsprung’s disease

Hirschsprung’s disease

1. anastomotic leak.2. stricture .3. retraction of the colon.4. fecal incontinence (soiling or encopresis ).5. persistant constipation

COMPLICATION

Distinguishing features between childhood functionalconstipation and Hirschsprung’s disease

Hirschsprung’s Disease Functional Constipation

Feature

At birth 2-3 years OnsetCommon Rare Delayed passage of meconiumCommon Rare Obstructive symptomsRare Common Withholding behaviorRare Common Fear of defecation

Rare Common Fear of incontinenceSmall, ribbon-like Very large Stool sizeCommon Rare Poor growth

Possible Never EnterocolitisNarrowed Enlarged Rectal ampullaRare Common Stool in ampullaTransitional zone, delayedemptying

Lg amount of stools,no transitional zone

Barium enema

Absent rectosphincteric refl ex Normal Anorectal manometry

No ganglion cells, nerve hypertrophy and increase acetylcholinesterase activity

Normal Rectal biopsy

http://www.cincinnatichildrens.org/health/h/hirschsprung/

https://www.nlm.nih.gov/medlineplus/ency/article/001140.htm

http://www.mayoclinic.org/diseases-conditions/hirschsprungs-disease/basics/definition/con-20027602

https://en.wikipedia.org/wiki/Hirschsprung%27s_disease

http://emedicine.medscape.com/article/178493-overview

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