The effect of prophylaxis with ertapenem versus cefuroxime/metronidazole on intestinal carriage of carbapenem-resistant or third-generation-cephalosporin-resistant Enterobacterales after colorectal surgery.

OBJECTIVES: Compared to cephalosporin-based prophylaxis, ertapenem prophylaxis lowers the risk of surgical site infection among carriers of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-PEs) undergoing colorectal surgery. We aimed to determine whether ertapenem prophylaxis leads to increased postoperative colonization with carbapenem-resistant Enterobacterales (CREs) and third-generation-cephalosporin-resistant Enterobacterales (3GCR-Es). METHODS: This study was nested within a quality improvement study of prophylaxis for ESBL-PE carriers undergoing colorectal surgery. Patients were screened 4-6 days after surgery for carriage of ESBL-PEs or other 3GCR-Es and CREs. When CREs were detected, pre- and postsurgical clones were compared using Fourier-transform infrared (FT-IR) spectroscopy. RESULTS: The sample consisted of 56 patients who carried ESBL-PEs before surgery and received cefuroxime/metronidazole prophylaxis (Group 1), 66 who carried ESBL-PEs before surgery and received ertapenem (Group 2), and 103 ESBL-PE non-carriers who received cefuroxime/metronidazole prophylaxis (Group 3). CRE carriage was detected postoperatively in one patient (1.5%) in Group 2 versus eight patients (14.3%) in Group 1 (RD -12.8%; 95%CI -22.4% to -3.1%). For seven out of nine patients, preoperative ESBL-PE and postoperative CRE isolates were compared; in five of them, the pre- and postoperative clones were identical. Postoperative 3GCR-E carriage was detected in 37 patients (56.1%) in Group 2 versus 46 patients in Group 1 (82.1%) (aRD -20.7%, 95%CI -37.3% to -4.1%). CONCLUSIONS: Among ESBL-PE carriers undergoing colorectal surgery, detection of short-term postsurgical colonization by CREs and 3GCR-Es was significantly lower among patients who received ertapenem prophylaxis than those who received cephalosporin-metronidazole prophylaxis. Resistance development in a colonizing bacterial clone, rather than carbapenemase acquisition, was the major mechanism of carbapenem resistance.

Personalized Ertapenem Prophylaxis for Carriers of Extended-spectrum ß-Lactamase-producing Enterobacteriaceae Undergoing Colorectal Surgery.

BACKGROUND: Carriers of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) who receive cephalosporin-based prophylaxis have twice the risk of surgical site infection (SSI) following colorectal surgery as noncarriers. We tested whether ESBL-PE screening and personalized prophylaxis with ertapenem reduces SSI risk among carriers. METHODS: We conducted a prospective nonrandomized, nonblinded, interventional study in 3 hospitals in Israel, Switzerland, and Serbia. Patients were screened for ESBL-PE carriage before elective colorectal surgery. During the baseline phase, departmental guidelines advised prophylaxis with a cephalosporin plus metronidazole. In the intervention phase, guidelines were changed for ESBL-PE carriers to receive ertapenem. The primary outcome was any type of SSI within 30 days. We calculated adjusted risk differences (ARDs) following logistic regression. RESULTS: The intention-to-treat analysis compared 209 ESBL-PE carriers in the baseline phase to 269 in the intervention phase. SSI rates were 21.5% and 17.5%, respectively (ARD, -4.7% [95% confidence interval {CI}, -11.8% to 2.4%]). Unplanned crossover was high (15%), so to assess efficacy we performed an as-treated analysis comparing 247 patients who received cephalosporin-based prophylaxis with 221 who received ertapenem. SSI rates were 22.7% and 15.8%, respectively (ARD, -7.7% [95% CI, -14.6% to -.8%]), and rates of SSI caused by ESBL-PE were 6.5% and 0.9%, respectively (ARD, -5.6% [95% CI, -8.9% to -2.3%]). There was no significant difference in the rate of deep SSI. The number needed to treat to prevent 1 SSI in ESBL-PE carriers was 13. CONCLUSIONS: Screening for ESBL-PE carriage before colorectal surgery and personalizing prophylaxis for carriers is efficacious in reducing SSI.

Carriage of Extended-spectrum Beta-lactamase-producing Enterobacteriaceae and the Risk of Surgical Site Infection After Colorectal Surgery: A Prospective Cohort Study.

BACKGROUND: Antibiotic prophylaxis that covers enteric pathogens is essential in preventing surgical site infections (SSIs) after colorectal surgery. Current prophylaxis regimens do not cover extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE). We aimed to determine whether the risk of SSI following colorectal surgery is higher in ESBL-PE carriers than in noncarriers. METHODS: We conducted a prospective cohort study of patients who underwent elective colorectal surgery in 3 hospitals in Israel, Switzerland, and Serbia between 2012 and 2017. We included patients who were aged ≥18 years, were screened for ESBL-PE carriage before surgery, received routine prophylaxis with a cephalosporin plus metronidazole, and did not have an infection at the time of surgery. The exposed group was composed of ESBL-PE-positive patients. The unexposed group was a random sample of ESBL-PE-negative patients. We collected data on patient and surgery characteristics and SSI outcomes. We fit logistic mixed effects models with study site as a random effect. RESULTS: A total of 3600 patients were screened for ESBL-PE; 13.8% were carriers SSIs occurred in 55/220 carriers (24.8%) and 49/440 noncarriers (11.1%, P < .001). In multivariable analysis, ESBL-PE carriage more than doubled the risk of SSI (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.50-3.71). Carriers had higher risk of deep SSI (OR, 2.25; 95% CI, 1.27-3.99). SSI caused by ESBL-PE occurred in 7.2% of carriers and 1.6% of noncarriers (OR, 4.23; 95% CI, 1.70-10.56). CONCLUSIONS: ESBL-PE carriers who receive cephalosporin-based prophylaxis are at increased risk of SSI following colorectal surgery.