[size=20px]A two year old child is admitted to the hospital for enterocolitis. At seven days of age he underwent a laparoscopic-assisted pull-through procedure for Hirschsprung disease with a transition zone identified by frozen section at the rectosigmoid junction. He has undergone intermittent treatment with anal Botox injections, oral metronidazole and home bowel washouts. A contrast enema done two weeks prior to this admission appeared normal. He has been admitted four times during the last six months.

 

After stabilizing the patient, what is the best next step in his management?

 

A diverting colostomy

 

B change antibiotics

 

C rectal dilations

 

D appendicostomy for antegrade enemas

 

E rectal biopsy[/size]

E

E.

Missed segment should be evaluated befor any decision

correct answer

E rectal biopsy

 

This child presenting with recurrent enterocolitis after surgery for Hirschsprung disease may have retention of a segment of aganglionic bowel or transition zone in his pull-through. The appropriate next step is to obtain a rectal biopsy to evaluate the presence of ganglion cells. All the other options listed may provide temporary relief for the patient, but may not definitively address the issue leading to recurrent enterocolitis.

 

 

Delineating the transition zone prior to operation poses numerous difficulties. Contrast studies vary widely in their ability to identify the transition zone. The histologic definition is also varied but features such as hypertrophic nerve trunks, hypoganglionosis and partial circumferential aganglionosis are cited. It is accepted that ganglion cells are seen in a gradient fashion through the transition zone, and the length of this gradient has been described to extend from 2-5 cm. Other investigators have reported the transition zone may extend up to 13 cm in children with rectosigmoid disease and up to 22 cm in children with long-segment Hirschsprung disease. The routine adoption of the histologic identification of normal ganglion cells without nerve trunk hypertrophy in a circumferential fashion of the margin of the proximal pull-through segment may help diminish the risk of a transition zone pull-through.

 

The use of calretinin staining has been shown to be helpful in the diagnosis of primary HD as well as residual HD after pull-through.