To characterize the microbiology of hepatobiliary surgical site infections (SSIs) and to explore the relationship between specific antimicrobial prophylaxis regimens and the development of SSIs.

Retrospective matched case-control study comparing patient, procedure, and antimicrobial prophylaxis characteristics among patients undergoing a hepatobiliary surgical procedure with and without an SSI.

A tertiary referral acute-care facility.

Patients undergoing procedures defined as “BILI” (bile duct, liver, or pancreas surgery) using National Healthcare Safety Network (NHSN) definitions, excluding those undergoing concomitant liver transplantation, from January 2013 through June 2016 were included in the study population. The SSIs were identified through routine infection control surveillance using NHSN definitions. All patients who developed an SSI were considered cases. Controls were selected randomly matched 2:1 with cases based on fiscal quarter of the procedure. Logistic regression modeling was performed to explore variables associated with SSI, including antimicrobial prophylaxis received.

Among 975 procedures, 80 (8.2%) resulted in an SSI. Most cases involved an organism nonsusceptible to standard prophylaxis regimens, including cefazolin (68.8%), cefazolin plus metronidazole (61.3%), and ampicillin-sulbactam (52.5%). In a multivariate model, antimicrobial coverage against Enterococcus spp (aOR, 0.58; 95% confidence interval [CI], 0.17–2.04; P=.40) and against Pseudomonas spp (aOR, 2.40; 95% CI, 0.56–10.29; P=.24) were not protective against the development of an SSI. The presence of a documented β-lactam allergy was significantly associated with the development of an SSI (aOR, 3.54; 95% CI, 1.36–9.19; P=.009).

Although SSIs at the study institution were associated with pathogens nonsusceptible to the most commonly used prophylaxis regimens, broader-spectrum coverage was not associated with a reduction in SSIs.

Infections following cardiovascular implantable electronic device (CIED) procedures, including pacemaker and implantable cardioverter–defibrillators, are devastating and costly. Preimplantation prophylactic antimicrobials are effective for reducing postprocedural infections. However, routine postprocedural antimicrobials are not associated with improved outcomes, and they may be harmful. Thus, we sought to characterize antimicrobial use patterns following CIED procedures.

All patients who underwent CIED procedures from October 1, 2007 to September 30, 2013 and had procedural information entered into the VA Clinical Assessment Reporting and Tracking (CART) software program were included in this study. All antibiotic prescriptions lasting more than 24 hours following device implantation or revision were identified using pharmacy databases, and postprocedural antibiotic use lasting more than 24 hours was characterized.

In total, 3,712 CIED procedures were performed at 34 VA facilities on 3,570 patients with a mean age of 71.7 years (standard deviation [SD], 11.1 years), 98.4% of whom were male. Postprocedural antibiotics >24 hours were prescribed following 1,579 of 3,712 CIED procedures (42.5%). The median duration of therapy was 5 days (interquartile range [IQR], 3–7 days). The most commonly prescribed antibiotic was cephalexin (1,152 of 1,579; 72.9%), followed by doxycycline (118 of 1,579; 7.47%) and ciprofloxacin (93 of 1,579; 5.9%). Vancomycin was used in 73 of 1,579 prescriptions (4.62%). Among the highest quartile of procedural volume, prescribing practices varied considerably, ranging from 3.2% to 77.6%.

Nearly 1 in 2 patients received prolonged postprocedural antimicrobial therapy following CIED procedures, and the rate of postprocedural antimicrobial therapy use varied considerably by facility. Given the lack of demonstrated benefit of routine prolonged antimicrobial therapy following CIED procedures, antimicrobial use following cardiac device interventions may be a potential target for quality improvement programs and antimicrobial stewardship.

Infect Control Hosp Epidemiol 2016;37:1005–1011

To determine risk factors for vancomycin-resistant Enterococcus (VRE) colonization during a hospital outbreak and to evaluate Centers for Disease Control and Prevention (CDC)-recommended control measures.

Epidemiological study involving prospective identification of colonization and a case-control study.

A university hospital.

Patients on eight wards involved in outbreak from late 1994 through early 1995.

Cases were matched by ward and culture date with up to two controls. Risk factors were evaluated with four multivariate models using conditional logistic regression. The first evaluated proximity to other VRE patients and isolation status. The second evaluated proximity to unisolated VRE cases and three variables independently predictive after adjustment for proximity. The third evaluated seven significant univariate predictors in addition to proximity to unisolated VRE in backward, stepwise logistic regression. The fourth assessed proximity to VRE with all other variables collected, clustered in a principal components analysis. Pulsed-field gel electrophoresis was performed to assess clonality of two outbreak strains.

The incidence of transmission declined significantly after CDC guidelines were implemented. Proximity to unisolated VRE cases during the prior week was a significant predictor of acquisition in each of four multivariate models. Other significant risk factors in multivariate models included a history of major trauma and treatment with metronidazole. Pulsed-field gel electrophoresis confirmed the clonality of two outbreak strains.

VRE was transmitted between patients during a hospital epidemic, with proximity to previously unisolated VRE patients being an important risk factor. Weekly surveillance cultures and contact isolation of colonized patients significantly reduced spread.