Hirschsprung disease is a developmental disorder characterized by absence of ganglia in the distal colon, resulting in a functional obstruction[1]. Most cases of Hirschsprung disease are diagnosed in the newborn period. Hirschsprung disease should be considered in any newborn that fails to pass meconium within 24-48 hours of birth. Older children with Hirschsprung disease usually have chronic constipation since birth. They may also show evidence of poor weight gain. Despite significant constipation and abdominal distension, children with Hirschsprung disease rarely develop encopresis. In contrast, children with functional constipation or stool-withholding behaviors more commonly develop encopresis.

Physical examination in the newborn period is often nondiagnostic; however, it may reveal a distended abdomen and/or anal spasm. In older children, abdominal distension may result from the inability to release flatus.

Plain abdominal radiographs may show distended bowel loops with a paucity of air in the rectum.

Contrast enema is useful in establishing the diagnosis. With regard to barium enema, avoid washing out the distal colon with enemas before obtaining the contrast enema because this may distort a low transition zone. The catheter is placed just inside the anus without inflation of the balloon to avoid distortion of a low transition zone and perforation. Radiographs are taken immediately after hand injection of contrast and 24 hours later.

The classic finding of Hirschsprung disease is a narrowed distal colon with proximal dilation; however. Retention of rectal contrast for longer than 24 hours after the barium enema has been performed also suggests a diagnosis of Hirschsprung disease.

Anorectal manometry detects the relaxation reflex of the internal sphincter after distension of the rectal lumen. This normal inhibitory reflex is presumed absent in patients with Hirschsprung disease.  It was refined but has fallen out of favor because of its many limitations. Sedation is usually necessary[2].

Full-thickness rectal biopsy remains the criterion standard. The definitive diagnosis of Hirschsprung disease is confirmed by a full-thickness rectal biopsy demonstrating absence of ganglion cells. The specimen must be obtained at least 1.5 cm above the dentate line because aganglionosis may normally be present below this level. Disadvantages of full-thickness rectal biopsy include the frequent necessity of general anesthesia and risks of bleeding and scarring.

Surgical management of Hirschsprung disease begins with the initial diagnosis, which often requires a full-thickness rectal biopsy. Traditionally, a diverting colostomy was created at the time of diagnosis, and definitive repair depending on the surgeons choice. Once the diagnosis is confirmed, the definitive treatment is to remove aganglionic bowel and to restore continuity of the healthy bowel with the distal rectum.

A number of definitive procedures have demonstrated excellent results when performed by experienced surgeons. The most commonly performed repairs are the Swenson, Duhamel, and Soave procedures.

A laparoscopic approach to the surgical treatment of Hirschsprung disease was first described in 1999 by Georgeson[3].The transition zone is first identified laparoscopically, after which the rectum is mobilized below the peritoneal reflection. A transanal mucosal dissection is performed, and the rectum and aganglionic bowel is prolapsed through the anus. The healthy proximal bowel is anastomosed to the rectal cuff. Functional outcomes of this laparoscopic approach appear to be equivalent to open techniques based on short-term results[3,4,5].

 

One-stage pull-through has been noted to be particularly beneficial in infants younger than 3 months of age. Recent advances in minimal-access surgery have led to the successful application of laparoscopic-assisted techniques for the surgical management of diseases of the colon.

 

References:

1. Heanue TA, Pachnis V. Enteric nervous system development and Hirschsprung’s disease: advances in genetic and stem cell studies.Nat Rev Neurosci. 2007 Jun. 8(6):466-79.
2. Pensabene L, Youssef NN, Griffiths JM, Di Lorenzo C. Colonic manometry in children with defecatory disorders. role in diagnosis and management.Am J Gastroenterol. 2003 May. 98(5):1052-7.
3. Georgeson KE, Cohen RD, Hebra A, et al. Primary laparoscopic-assisted endorectal colon pull-through for Hirschsprung’s disease: a new gold standard.Ann Surg. 1999 May. 229(5):678-82; discussion 682-3.
4. de Lagausie P, Berrebi D, Geib G, Sebag G, Aigrain Y. Laparoscopic Duhamel procedure. Management of 30 cases.Surg Endosc. 1999 Oct. 13(10):972-4.
5. Curran TJ, Raffensperger JG. Laparoscopic Swenson pull-through: a comparison with the open procedure.J Pediatr Surg. 1996 Aug. 31(8):1155-6; discussion 1156-7.