Anastomotic Leak Possibility Increased with C diff Infection

Sarah E. Baker, MD

Having a Clostridium difficile infection (C diff) can increase the likelihood of a feared colorectal surgery complication called anastomotic leak, according to a paper published in The American Journal.

Investigators from around the US conducted a nationally-representative case-control study in order to evaluate the effect of C diff infection on anastomotic leak in colectomy patients.

The investigators explained that C diff is a known collagenase-producing bacteria and it’s possible that it contributes to anastomotic leak, which is a feared complication following colorectal surgery. Anastomotic leak can increase morbidity, mortality, and length and cost of hospital stays.

Patients undergoing elective colorectal resection between 2015-2016 were eligible for inclusion in the study. Ultimately, the investigators identified 46,735 eligible participants and the mean age was 61 years. Half of the patients were women and 72% were Caucasian.

A small number developed C diff infection (1.5%), 3.1% developed a post-operative anastomotic leak, and 1.6% died, the investigators learned.

The patients who developed C diff infection were more likely to be older, women, and have comorbidities such as COPD or pre-operative AKI.

Additionally, the patients more likely to develop C diff also had elevated pre-operative WBC, higher pre-operative creatinine, lower albumin, emergent compared to elective operation, higher American Society of Anesthesiologists (ASA) class, no pre-operative mechanical or antibiotic bowel preparation, contaminated or dirty/infected operative wound, wound dehiscence, superficial or deep surgical site infection, death, and longer length of stay.

C diff infections were also significantly associated with procedures by indications, the study authors learned: emergent (5%), bleeding (4%), diverticular (1.5%), neoplasm (1.3%), other (1.3%), and IBD (1.3%).

The investigators also created an algorithm for machine learning to determine that C diff infection significantly increased the odds of anastomotic leak. Infection increased length of stay by nearly 4 days, but there was no increase in mortality.

Compared to those without C diff infection, having the infection increased the likelihood of anastomotic leak from 3.82-6.81%, the study authors said. C diff infections also increased the likelihood of anastomotic leak in dose-dependent fashion with increasing ASA class (I to IV) to 4.27%, 5.71%, 7.58%, and 10.00%, respectively.

“This is the first known nationally representative study on C diff infection and anastomotic leak, mortality, and length of stay among colectomy patients,” the study authors wrote, while noting that their findings are aligned with other published literature.

The researchers also said that even though it is important to maintain cost-effective practices for health resources, their findings offer evidence that there could be an underappreciated risk of undiagnosed C diff infection in a post-operative colorectal surgery population. Selective testing of this population could allow for earlier diagnosis, treatment, and outcome optimization, they suggested.

“The adverse clinical and financial outcomes for both C diff infection and anastomotic leak are widely recognized,” the study authors added. “A high index of suspicion and selective testing of higher risk colectomy patients may potentially allow for earlier diagnosis and treatment to optimize outcomes.”

The findings were also presented as an oral presentation during the 2019 ACS Clinical Congress in October 2019.