[size=20px]A four-year old boy underwent anoplasty for anorectal malformation with rectourethral fistula. He presents to clinic after being lost to follow-up. Mom reports constant leakage of stool in his diaper. Physical exam reveals a slightly distended abdomen, good position of the neoanus with no stricture and poor gluteal muscles. An abdominal radiograph shows a significant amount of stool and an abnormal sacrum. A contrast enema shows a very dilated rectosigmoid that is full of stool.

 

What is the most appropriate initial management in this child with encopresis after repair of an anorectal malformation?

 

A large volume saline enemas

 

B high dose laxatives

 

C small volume phosphate (Fleet®) enemas

 

D manual disimpaction

 

E sigmoidectomy[/size]

a

(Untitled)

 

A

A

correct answer

A large volume saline enemas

 

Fecal incontinence is common in patients with surgically corrected anorectal malformations (ARM). The majority of patients can be successfully managed with a bowel management program. The use of laxatives, antimotility agents, enemas and colonic irrigations play a key role in the management of fecal incontinence provided they are used with a specific rationale.

 

A carefully history and examination are vital in patients with ARMs and fecal incontinence and should include the following.

• obtain a thorough history of the patient’s bowel habits including a record of previous bowel regimens attempted
  
• complete the VACTERL (vertebral, anal, cardiac, tracheoesophageal, renal, limb) work-up, specifically ensuring the spine and sacrum have been adequately imaged
  
• understand the nature of the defect and the quality of the muscles at the time of surgery
  
• document the position of the rectal opening in relation to the anal muscle complex, the size of the rectal opening (using Hegar dilators) and the quality of the gluteal cleft
  

Strictures and an abnormally placed anus should be ruled out. An exam under anesthesia with muscle stimulation may be required to confirm adequate position of the anus. In addition, magnetic resonance imaging can help determine the position of the rectum through the muscle complex.

 

Abdominal radiographs can help determine the initial extent of fecal retention. Follow-up radiographs can help monitor the success of the bowel management regimen. Contrast enema is useful in distinguishing whether incontinence is due to constipation or hypermotility. Patients with incontinence due to constipation typically have some degree of megarectosigmoid on contrast enema. These patients are best treated with daily, large volume saline enemas. Patients with hypermotility will usually have a nondilated colon without sigmoid redundancy on contrast enema. These patients are best treated with small volume enemas and antimotility agents. Patients with a tendency for constipation had a higher success rate with bowel management program compared to those with a tendency towards diarrhea.

 

High dose laxatives are used for patients with overflow pseudoincontinence. These patients tend to have a low lesion with a technically sound operation, normal sacrum and well developed sphincters and musculature. If patients are continent with laxatives, then these patients are suffering from overflow pseudoincontinence and may benefit from sigmoid resection. If these patients are not continent with laxatives, then a bowel management regimen should be instituted as described above. (SL/DP)