A 34-year-old man with a history of Crohn disease presents with foul-smelling drainage from his abdominal wall. He has experienced malaise and poor oral intake over the preceding 3 weeks and had been having worsening abdominal pain for 5 days. In the last 3 days, he noticed swelling of his abdominal wall superior to his umbilicus, in an area that began to drain foul-smelling, greenish drainage. The area has become erythematous and very tender. The drainage has increased in volume over the past 24 hours to the point that it saturates his clothes, and he has started to develop fevers, chills, and dark urine. On arrival he has the following vitals:
A CT scan shows oral contrast extravasation from the small bowel that exits at the site of drainage, but no drainable fluid collection in the abdominal wall.
Which is the most appropriate management at this time?A. Take the patient to the OR urgently for exploratory laparotomy
Correct Answer: B
This patient presents with a new enterocutaneous fistula (ECF). Patients with inflammatory bowel disease (IBD) are particularly prone to ECF formation. These often present following a prior operation but can also appear spontaneously, particularly in patients with IBD. When patients first present with an ECF, they are often volume depleted with electrolyte disarray from intestinal losses and can have sepsis. This requires broadspectrum antibiotics and drainage of any associated intra-abdominal abscesses if present. Depending on how proximal the fistula is, nutritional losses can be considerable. Patients should be started on TPN until the anatomy of the fistula is defined and output can be controlled. The anatomy can usually be defined with a CT scan with enteral and IV contrast, which has the added benefit of defining any undrained intraabdominal fluid collections. If the anatomy is unclear, a fistulagram can be performed, in which water soluble contrast is injected into the fistula’s external opening to identify the location of the fistula and any communication with any additional fistulas or abscess pockets. Wound care and control of the fistula effluent to minimize skin breakdown and manage output can be complex and may require the assistance of an enterostomal therapy or wound nurse.
In addition to identifying the location of the fistula, the cause and any factors that would inhibit closure should be identified. In this case, underlying IBD is the cause, and in these patients, medical treatment of the underlying Crohn disease should be optimized. Factors that can impair fistula closure include the presence of a foreign body (eg mesh used in herniorrhaphy), prior radiation exposure, undrained or untreated intraabdominal infection, malignancy as the cause of the fistula, distal intestinal obstruction, or immunosuppression. Whenever possible these perpetuating factors should be minimized or eradicated. When underlying factors cannot be addressed (for example prior radiation exposure), their recognition can at least allow accurate prognostication about the chances of spontaneous fistula closure and the need for surgery.
In any patient population—with or without IBD—principles of managing a new ECF include sepsis control, nutritional support, fluid and electrolyte repletion, and defining the anatomy and cause of the fistula. It is not recommended to take the patient to the OR urgently. The majority of ECFs will heal on their own, and if needed, surgery should be performed in a delayed manner when the patient has been well resuscitated, nutritional status is optimized, and intra-abdominal inflammation has subsided somewhat, often many months after the initial presentation. In this case incision and drainage is not needed as there is no drainable fluid collection in the abdominal wall on CT scan, but it is important to perform imaging with CT to evaluate undrained intra-abdominal or abdominal wall collections. Percutaneous jejunostomy tube would not be appropriate before fully defining the anatomy of the fistula. In this case, neither upper GI endoscopy nor colonoscopy would be beneficial, as we suspect this fistula to be located in the small bowel and there are more effective methods of localization that better depict the small bowel.