Manipulation of a Hospital Antimicrobial Formulary to Control an Outbreak of Vancomycin-Resistant Enterococci

Abstract

Infection control practices are not uniformly successful in limiting outbreaks of vancomycin-resistant enterococci (VRE). Despite the implementation of barrier precautions for VRE-infected patients, nearly one-half of the inpatients at our center were found to have gastrointestinal colonization by VRE. In an attempt to control the outbreak, we altered the antibiotic formulary by restricting the use of cefotaxime and vancomycin and adding beta-lactamase inhibitors to replace third-generation cephalosporins. The use of clindamycin was also restricted because of a concomitant outbreak of Clostridium difficile colitis. After 6 months, the average monthly use of cefotaxime, ceftazidime, vancomycin, and clindamycin had decreased by 84%, 55%, 34%, and 80%, respectively (P < .02). The point prevalence of fecal colonization with VRE decreased from 47% to 15% (P < .001), and the number of patients whose clinical specimens were culture positive also gradually decreased. A change in antibiotic use appears to have significantly affected our VRE outbreak when previous measures failed.

Evolving trends in multiple-antibiotic-resistant bacteria in liver transplant recipients: A longitudinal study of antimicrobial susceptibility patterns

“…At one institution where nearly one half the inpatients were found to be colonized with VRE, increased use of ␤-lactam and ␤-lactamase inhibitors, e.g., ampicillin-sulbactam and piperacillin-tazobactam, instead of third-generation cephalosporins was shown to significantly decrease VRE colonization. 2 It has also been proposed that the levels of piperacillin achievable in the bile and small intestine are greater than the minimum inhibitory concentrations of many VRE isolates, and piperacillin therefore may promote less colonization with VRE. 18 Ninety-one percent of all infections caused by S aureus in our liver transplant recipients were caused by MRSA, and the incidence of infections caused by MRSA increased significantly over time.…”

“…Not only have staphylococci and enterococci emerged as the foremost causes of nosocomially acquired bloodstream infections, but 32% to 75% of the Staphylococcus aureus isolates are currently methicillin resistant, and 12% to 47% of the enterococcal isolates are vancomycin resistant. [1][2][3][4][5] Although trends in the emergence of antimicrobial resistance are most notable among gram-positive bacteria, resistance to multiple antibiotics is also widely recognized in gram-negative bacteria. In a study from Europe, 65% of the Pseudomonas aeruginosa strains were multiple-antibiotic resistant.…”

Antimicrobial stewardship for inpatient facilities

“…However, a comprehensive infection control program, combined with an effective antimicrobial stewardship agenda, synergistically limit the emergence and spread of antimicrobial-resistant bacteria, reduce HAIs, control resistance, and improve overall inpatient care. 24,27 Hence, when instituting an antimicrobial stewardship program, it is essential to ensure the hospital or other healthcare institution already has a robust hospital epidemiology and infection control program in place-or to simultaneously institute one. Where having an infectious diseases physician as a core member and leader of the team is beneficial, it is not absolutely necessary.…”

Eradication of a Large Outbreak of a Single Strain of vanB Vancomycin-Resistant Enterococcus faecium at a Major Australian Teaching Hospital

“…Severe sepsis was treated with piperacillin/tazobactam. 20 Vancomycin use required approval by a clinical microbiologist or infectious diseases consultant.…”