Hirschprung disease by dr peter MD at CUHAS it is important

It is most common type of congenital malformation where a child presents with feeatures of intestinal obstruction

1. HIRSCHSPRUNG'S DISEASE
congenital megacolon
•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.

2. Incidence & Etiology
•INCIDENCE: 1\5000 live birth newborn
•70-80% is boys. (M / F. 4: 1 )
•Less common in blacks.

3. PATHOPHYSIOLOGY
The developmental disease characterized
by absence of ganglion cells in submucosal
(Meissner’s)
and myenteric (Aurbach’s) plexuses in distal
bowel extending proximally for variable
distances that result in functional intestinal
obstruction caused by dysmotility of the
diseased segment

4. •Hirschsprung’s disease is caused by the failure of
ganglion cells to migrate cephalocaudally through
the neural crest during fourth to 12 weeks of
gestation
• resulting into absence of ganglion cells in all or
part of the colon.
•The aganglionic segment usually begins at the
anus and extends proximally (caudally).
•Short-segment disease is most common and is
confined to the recto-sigmoid region of the colon.
•Long-segment disease can affect the entire colon.
Rarely, the small and large intestines are involved
PATHOPHYSIOLOGY

6. PATHOPHYSIOLOGY
•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.

7. PATHOPHYSIOLOGY
•The gross pathologic feature of HD is a dilated proximal intestine
with gradual or abrupt transition to normal constricted distal intestine
typically funnel like or cone shaped .
•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.

8. TYPES.
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:
- Non vascular causes like
Trypanosoma (chaga's disease).
Vit B1 def.

9. ASSOCIATED ANOMALIES
–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

10. Vertebral anomalies,
Anorectal anomalies (anal atresia),
Cardiac anomalies,
Tracheo-Esophageal fistula or atresia
Renal anomalies
and Limb anomalies
ASSOCIATED ANOMALIES :VACTERL

11. CLINICAL PRESENTATIONS:
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.
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.
7.And may have Growth retardation.
8.Multiple fecal masses on abdominal examination.

12. Diagnosis
History
failure to pass meconium, painless abdomenal distension & constipation)
Physical examinations
Distended abdomen with Multiple fecal masses on abdominal examination
on DREcharacteristically there is
• Anal sphincter is hypertonic
• Rectum is typically empty.
• Hard fecal mass.
Radiology
1.Plain x-rays of the abdomen :Erect & supine
2.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.
contrast enema should be done with out preparation of bowel,

13. 4.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.
5.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.
6.UltraSonography: for associated anomalies.

14. Management:
Manegement of HD differs accosrding to the presentation form and clinical
situation of the patients:
•Acute I.O. : if the patient presents with acute intestinal obstruction in the
early life the management will be
–resuscitation ,
–NGT , NPO
–IVF ,
–Antibiotics ,
–Rectal tube,irrigations .
–The initial treatment requires performing a "leveling" colostomy in the most distal
colon with ganglion cells present. This requires exploration with multiple
seromuscular biopsies of the colon wall to determine the exact extend of the
aganglionosis. The colostomy is placed above the transition zone. Placement of
the colostomy in an area of aganglionosis will lead to persistent obstruction
–When the patient becomes stable, then the definitive treatment will be planned.
•Chronic constipation :
–laxative
–saline enema.
–Work up to establish the diagnosis
–then the definitive treatment will be planned

15. Definitive procedures:
Once the child has reached an adequate size and age (6-12 months; 20 pounds or
more), a formal pull-through procedure is done
1.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.
2.LAPAROSCOPY .
3.TEPT transanal endorectal pullthrough (without laparotomy )

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

17. Take home message/
know other congenital anomalies