Substantial Variation Seen in Ileosigmoid Fistula Management in Crohn’s Disease

—
Researchers call for evidence-based guidance, but expert advocates for surgeon’s choice

by
Tara Haelle, Contributing Writer, MedPage Today
December 14, 2024

ORLANDO — A considerable amount of variability exists in surgical management of ileosigmoid fistulas in Crohn’s disease (CD), according to a recent meta-analysis.

Findings from six studies revealed that emergency surgery rates ranged from 5.7% to 57% and diversion rates ranged from 11.9% to 57%, reported Imran Khan, MD, of the Cleveland Clinic, at the Advances in Inflammatory Bowel Diseases annual meeting.

“I think the main takeaway from this systematic review for us was that there is no standardized way of surgically managing these fistulas, indicated by the high heterogeneity,” Khan told MedPage Today. He noted the heterogeneity estimates his group found were I²=95% for laparoscopic versus open surgery, and I²=90% for primary repair versus resection.

The findings suggest “a need for standardized treatment guidelines to improve consistency in care,” the authors wrote in their poster. They recommended that a multi-center study be conducted to help develop evidence-based guidelines for management of ileosigmoid fistula.

Fistulas of any kind occur at a rate of about 18-34% in CD, with ileosigmoid fistulas occurring in about 5% of patients with CD and in 20% of those with fistulizing abdominal Crohn’s. Past research looking at surgical strategies also has noted the absence of clear recommendations for guiding surgeons in management of the condition.

Khan and colleagues conducted a systematic review and meta-analysis of published studies through August 6, 2024 that reported on preoperative, intraoperative, and postoperative courses of patients with ileosigmoid fistulas. From an initial pool of 128 articles, they identified six that met their inclusion criteria of English-language studies published since 2000, including five retrospective cohort studies and one prospective case series.

“Substantial heterogeneity was observed in surgical approaches and outcomes” across the 493 combined patients, the authors reported. They found that 44% of patients underwent laparoscopy (95% CI 0.21-0.69) compared to 56% with open surgery. In addition, 41.3% underwent primary repair versus 58.7% who had sigmoid resection.

Just under a third of fistulas (29%) were identified preoperatively. The anastomotic leak rate was 8.34% (95% CI 0.06-0.11), with no significant difference in leak rates between those who underwent primary repair and those requiring resection (pooled P=0.22). However, resection was associated with a longer hospital stay (pooled P=0.007). The researchers also noted that two studies found a significant association between sigmoid resection and diversion (pooled P=0.0002) and an association between small bowel resection and higher diversion rates (pooled P=0.003).

Timothy Ritter, MD, of the GI Alliance Research in Southlake and TCU School of Medicine in Fort Worth, both in Texas, explained that management of ileosigmoid fistula really depends on what the interoperable findings are as well as the experience and comfort level of the surgeon.

“Some patients clearly need an ostomy, but some patients don’t. It really depends on what you find in the abdomen of the patient,” Ritter told MedPage Today. “While guidelines are often helpful in general terms, every patient is different, and a surgeon should determine the best surgical approach for the patient based on the operative findings and not be forced to Follow @ , or be held accountable for not following, a prescribed guideline.”

Ritter said he did not think ileosigmoid fistula management necessarily would benefit from attempts to develop a clinical guideline given how much variation occurs in patients and in different clinical scenarios.

“I think it’s hard to standardize something that has such a high variability,” said Ritter, who was not involved in the study. “I think it lends itself to a surgeon’s experience and a patient’s clinical course and where they are — how malnourished they are, how bad the disease is, how bad the inflammation is, what their previous surgical history is, and what the current assessment of their fistula disease is.”

Khan noted that the emergency surgery rates refer to a combination of laparoscopic and open surgery. “I think this speaks to the expertise of the surgeon and institute and their comfort level with approaching these in a minimally invasive way,” he said.