Antimicrobial Stewardship

Steven Park, MD/PhD

Associate Professor of Clinical Medicine

Director, Antimicrobial Stewardship Program

Director, Fellowship Program

Division of Infectious Diseases

UCI Medical Center

Objectives

Review UCI Antimicrobial Stewardship Program (ASP)

Review Rapid Disc Diffusion Susceptibility Testing for GNR bacteremia

Discuss future plans for UCI ASP (focus on Hospitalist Teams)

• Formulary restriction Certain antimicrobials require justification or approval from a designated

gatekeeper

• Prospective audit Post-prescription review of appropriateness of antibiotic use Performed at 48-72 hours after initial prescription

• Clinical guidelines and education Multi-disciplinary, evidence based guidelines on optimal treatment of

various infections Based on local antibiogram Educational lectures to specific subspecialties

• Others Computerized order entry and surveillance systems (EPIC) Rapid diagnostics (direct sensitivity, ACCELERATE) Biomarkers (pro-calcitonin) Antibiotic time out Allergy assessment Quality improvement projects (carbapenems and UTI’s)

UCI Antimicrobial Stewardship Program

The California Antimicrobial Stewardship Program Initiative

Antimicrobial Use at UCI

Stewardship interventions begin

Stewardship interventions begin

Antimicrobial Use at UCI

Antimicrobial Use at UCI

Stewardship interventions begin

QI Project: Targeting carbapenem use for UTI’s

ID division performed literature review on efficacy of non-carbapenems (cefepime, Zosyn) for treatment of urinary tract infections (including bacteremia) with ESBL pathogens

Concluded that cefepime and Zosyn are effective and ID would no longer approve carbapenems if the urine ESBL pathogen is sensitive to cefepime or Zosyn even with bacteremia

Carbapenem Use

Rapid Disc Diffusion Susceptibility Testing for GNR bacteremia (RDDT)

Advantage: Faster by 24-36 hours

Disadvantage: Not standardized, less experience, not CLSI approved.

How well does it correlate with standardized Kirby Bauer (DD) and Vitek tests?

RDDT: Advantages and Disadvantages

Comparison of RDDT and Vitek and Kirby Bauer (DD)

Results - interpretation

• Agreement (A): rapid sens = DD/Vitek

• Very Major (VM): rapid sens (S) DD/Vitek (R)

• Major (M): rapid sens (R) DD/Vitek (S)

• minor (m): other discrepancies

Rapid Disc Diffusion Susceptibility Testing for GNR bacteremia

Pilot study looking at 106 positive blood cx with GNR from July 2015 to Oct 2015

Rapid Disc Diffusion Susceptibility Testing conducted by the Microbiology laboratory in addition to standard susceptibility testing (Kirby Bauer (DD) and Vitek)

Reference Control N % of Total

CLSI Disc Diffusion Discrepancies

Very Major (VM) 2 0.1

Major (M) 26 1.4

Minor (m) 188 10.1

Complete Agreement (A) 1644 88.4

Total 1860 100

Reference Control N % of Total

Vitek Discrepancies

Very Major (VM) 2 0.1

Major (M) 37 2.2

Minor (m) 146 8.9

Complete Agreement (A) 1463 88.8

Total 1648 100

*2 VM: TMP/SMX for Enterobacter, and Tobra for ESBL E.coli

Rapid Sens compared to Disc Diffusion and Vitek (N=106)

*2 VM: Amp/SBT for E.coli and imipenem for proteus

The median time from BC positivity to RDDDT report was 17.5 hrs vs. 46 hrs for VITEK.

72/162 cases (44%) required antibiotic change with median time to optimization of 21 hrs based on RDDDT vs. 71 hrs based on prior baseline VITEK.

RDDT led to faster de-escalations but more escalations than Vitek RDDT was over calling resistance

Rapid Disc Diffusion Susceptibility Testing and ASP Intervention for GNR bacteremia

Accelerate Pheno™ system

• The Accelerate Pheno™ system uses a broad panel of fluorescence in-situ hybridization assays for microorganism identification.

• Morphokinetic Cellular Analysis (MCA) using time-lapse imaging for antimicrobial susceptibility testing (AST).

• The system can identify 16 organisms (six Gram positive and eight Gram negative bacteria as well as two Candida species) from positive blood cultures.

• It provides results in 1.25 hours for identification (ID), and AST and resistance phenotypes in about 7 hours.

• FDA approved • UCI Microbiology currently testing

Future ASP activities

ASP newsletter

Antibiotic allergy de-labelling (collaboration with Allergy and Immunology)

Comprehensive ID order set for EPIC

Physician dashboard providing feedback on antimicrobial use for individual physicians

Hospitalist Teams and Stewardship

2015-2016 academic year: 97/549 interventions made by ASP including Family and IM for a rate of 17.6% 2017 year: 167/1067 interventions made by ASP for a rate of 15.6%

How can we improve?

Skin/soft tissue infection Health care associated pneumonia Correlates with meeting metrics for PRIME

Management of Skin/Soft Tissue Infection IDSA Practice Guidelines 2014

Skin and Soft Tissue Infections: Proposal

No need to add vancomycin for cases of cellulitis given: • No purulent drainage • No evidence of abscess by exam and ultrasound (ED)

Healthcare Associated Pneumonia

Overly broad and HCAP removed from 2016 IDSA practice guidelines for HAP AND VAP

Healthcare Associated Pneumonia: Proposal

Retrospective chart review to identify risk factors for pseudomonas or MRSA pneumonia admitted to the hospital (not HAP or VAP)

If there are risk factors, cases undergo sputum collection in the ED

If sputum negative, antibiotics de-escalated or discontinued

Procalcitonin

Procalcitonin in respiratory tract infections

Cochrane review looked at 14 randomized controlled trials looking at procalcitonin algorithms in antibiotic decision making for acute respiratory infections

Lowered antibiotic use by 65% in primary care, 35% in ED, and 30% in ICU

Decreased antibiotic exposure in hospital by 3.5 days No difference in treatment failure or mortality at 30 days No firm conclusions on cost-effectiveness

Schuetz P et al. Procalcitonin to initiate or discontinue antibiotics in acute respiratory tract infections. Cochrane Review. 2012.

UCI Procalcitonin Algorithm1: Respiratory tract infections

PCT value

Antibiotic Recommendation

<0.1 mg/ml >0.24 mg/ml 0.1-0.24 mg/ml

Antibiotics strongly discouraged

Antibiotics discouraged

Antibiotics encouraged

PCT to initiate antibiotics

Consider viral infection Consider non-infectious cause

Repeat q2-3 days to consider stopping antibiotics See Algorithm 2

UCI Procalcitonin Algorithm2: Respiratory tract infections

PCT value

Antibiotic Recommendation

<0.1 mg/ml >0.24 mg/ml

Strongly recommend antibiotics be stopped

Recommend continuation of antibiotics

PCT to stop antibiotics

Make sure there is appropriate clinical response

If PCT rising or not decreasing, consider broadening coverage and/or ID consult

0.1-0.24 mg/ml

Recommend antibiotics be stopped

Antibiotics at time of admission

Proper antibiotic utilization at time of presentation to hospital is the most difficult to implement from stewardship perspective

Many times they are started on admission then discontinued or drastically de-escalated the next day

Pressure to discharge definitely a factor

Summary

• UCI Antimicrobial Stewardship Program is now up and running using advanced methods to meet its goals

• Future methods will be coming in the future (ACCELERATE, allergy de-labelling, etc.)

• Hospitalist teams are doing an excellent job in antibiotic utilization • We need to address SST, HCAP, and antibiotics at admission