Antimicrobial Stewardship

Define Antimicrobial Stewardship

• Antimicrobial stewardship is “coordinated interventions designed to improve and measure the appropriate use of antimicrobial agents by promoting the selection of the optimal antimicrobial drug regimen including dosing, duration of therapy, and route of administration

What are the basic interventions (2) of antimicrobial stewardship

• Preauthorization

• Prospective audit and feedback

Define Preauthorization

• Strategy to improve antibiotic use requiring clinicians to get approval for certain antibiotic BEFORE they are prescribed

• Typically require either ID authorization or ID consult

Define Prospective audit and feedback

• intervention that engages providers AFTER an antibiotic is prescribed

• Different models exist but typically focus on high cost, toxicity, or broad-spectrum antibiotics

  • ex: review of clindamycin use

• A provider starts an antibiotic (e.g., for suspected infection)

• Within ~24–72 hours, a stewardship team (ID physician/pharmacist) reviews:

  • Drug choice

  • Dose

  • Duration

  • Culture results

• They give feedback, such as:

  • De-escalate therapy

  • Change antibiotic

  • Stop therapy if unnecessary

Institution specific practice guidelines

Institution can develop facility-specified clinical practice guidelines coupled with a dissemination and implementation strategy

How does ASP (antimicrobial stewardship) reduce risk of CDI (C. diff infection)?

• ASP interventions can reduce use of antibiotics associated with a high risk of Clostridium difficile infections (CDI)

  • Focus on clindamycin and broad-spectrum antibiotics, esp. cephalosporins and quinolones

    • typically via prospective audit and feedback

• ASP reduces CDI by targeting high-risk antibiotics (clindamycin, cephalosporins, fluoroquinolones), typically using prospective audit and feedback to optimize or discontinue therapy.

PK monitoring and alternative dosing strategies

• ASPs can implement PK monitoring and adjustment programs for aminoglycosides and vancomycin

• ASPs can advocate for the use of alternative dosing strategies for broad-spectrum beta-lactams to decrease costs

• this strategy is used for toxicity prevention and efficacy of drugs with narrow therapeutic windows (AG, Vanc)

  • ASPs help ensure therapeutic levels without overdosing

IV to PO Convertions

• Increase both appropriate use of oral antibiotics for inital therapy and the timely transitions of patients from IV to oral antibiotics

  • Reduced drug costs

  • Reduced lengths of hospital stay

  • Patient convenience

• Typically done for antibiotics with high bioavailability (>90%)

Allergy Assessment

• ASP can promote allergy assessments and PCN allergy skin testing in patients with h/o beta-lactam allergy

• Personal health implications

  • Fewer efficacious antibiotic choices

  • More toxic effects w alternatives

  • Use of broad-spectrum antibiotics

  • More post-operative surgical-site infection

• Public Health Implications

  • Antibiotic resistance

  • Higher rates of C. diff infection

  • Use of more costly antibiotics

  • Increased length of hospital stay

Antibiograms and why they are so useful

• Development of stratified anti-biograms over non-stratified hospital-wide anti-biograms

• Used by clinicians to

  • Assess local susceptibility rates

    • Doctors can see which antibiotics work best against bacteria in their hospital or unit.

  • Aid in selection empiric antibiotic therapy

    • When the infection organism isn’t known yet, clinicians can choose antibiotics more likely to be effective based on local patterns.

  • Monitor resistance over time within an institution

    • Track whether certain bacteria are becoming more resistant, helping hospitals adjust policies.

Rapid Diagnostic Testing

• Typically used on specific types of cultures to allow RAPID identification of microorganisms (usually within hours) and some resistance genes via PCR

  • Ensures treatment appropriate

  • Faster de-escalation

Selective MIC reporting

• Reporting susceptibility data for limited number of antibiotics instead of all antibiotics tested

• Some factors considered

  • Formulary

  • Sites of infection

• Improves appropriateness of prescriptions

• What it is:

  • When a lab tests a bacteria for which antibiotics will work, they don’t always show all possible antibiotics.

  • Instead, they only report a selected set of antibiotics that are most relevant.