Hirschsprung disease

 

It is a common cause of neonatal colonic obstruction, more common in boys & in few dysmorphic syndromes including Downs.

 

Aganglionic section in distal colon causing dysmotility, spasms, poor contractility and poor peristalsis. This leads to a functional obstruction at junction of proximal ‘normal’ and distal affected bowel segment. Commonest finding is a short segment disease in sigmoid colon or rectum, but less common is whole colon disease and rarely small bowel disease.

 

Presentation

– Most newborn babies with Hirschsprung will not pass meconium within 24 hours after birth (although a small percentage might).

– Frequently babies have obstructive features with bilious vomiting and abdominal distension.

– Undiagnosed babies could get enterocolitis or peritonitis with sepsis.

 

– Some young children present with chronic constipation, especially if only a short segment affected.

– They usually present with 2 months age, and nearly always before school age.

– Suspect if poor response to ‘usual’ therapies with laxatives.

 

– Rectal examination demonstrates a tight elongated but ‘empty’ rectum with no palpable stools, however there can be an explosive expelling of stools with finger is withdrawn.

 

Investigations

X-ray of abdomen: Dilated bowel loops, often until descending colon due to distal intestinal obstruction.

Barium enema: narrow rectum and sigmoid compared to a proximal the descending colon, with a saw-tooth appearance to the wall and a clear transition zone.

Ano-rectal manometry may be useful in distinguishing other causes of constipation, but not commonly done.

Rectal suction biopsy reveals aganglionic submucosa within the affected segment is diagnostic.

 

Management

– Surgical treatment by removing the affected portion of the colon, with good prognosis for bowel control.

– This can be a ‘single stage’ pull through or a multi-staged procedure involving colostomy.

– Some cases complicated by perforation. Few require a stoma if bowel control not achieved.

 

Also see Constipation