959. Communicating Microbiology Results: It’s Not Just What You Say, But How You Say It.
Session: Oral Abstract Session: Stewardship Tools
Friday, October 6, 2017: 9:15 AM
Room: 05AB
Background: Gaps in microbiology communication can lead to suboptimal antibiotic prescribing. In May 2016, our laboratory modified reporting of respiratory cultures growing commensal flora only to specify “no methicillin-resistant Staphylococcus aureus/MRSA or Pseudomonas aeruginosa“(PA). The purpose of this study was to compare MRSA & PA antibiotic therapy utilization before and after the change.

Methods: IRB approved, quasi-experiment at 4 hospitals with an antimicrobial stewardship program. Dates: 8/1/15 – 1/31/16 & 8/1/16 – 1/31/17. Included: ≥ 18 years, commensal flora only respiratory culture, empiric MRSA & PA antibiotic for treatment of lower respiratory infection. Excluded: non-respiratory infection. Primary outcome: MRSA or PA therapy de-escalated. Secondary outcomes: time to culture result, MRSA & PA antibiotic days of therapy, length of stay. Safety outcomes: acute kidney injury (AKI), C. difficile(CDI), subsequent multi-drug resistant organism (MDRO), in-hospital all-cause mortality.

Results: 210 patients included, 105 per group. Median age 64 & 61 years, male sex 52% & 56% in pre & post group, respectively. Empiric antibiotics, pre vs. post: vancomycin 94% vs. 95%; cefepime 66% vs. 36%; piperacillin-tazobactam 10% vs 46%. MRSA or PA antibiotics de-escalated: 39% pre & 73% post (P < 0.001). See table 1 for variables associated with antibiotic de-escalation. Days of therapy: 7 vs. 5 days (P < 0.001). AKI 31% vs. 14% (P = 0.003). 8 subsequent MDRO in pre & 1 in post (P = 0.035). No differences: time to culture result, length of stay, mortality, CDI.

Conclusion: Improved microbiology communication to assist prescriber interpretation of commensal respiratory flora was associated with a reduction in the proportion of patients that received antibiotics targeting MRSA & PA.

Table 1.

Antibiotic

de-escalation

No antibiotic de-escalation

Unadjusted OR [CI]

Adjusted OR [CI]

No MRSA, no PA comment

77 (65%)

28 (30%)

5.0 [2.5 – 10.0]

5.7 [2.9 – 11.0]

Charlson Comorbidity Index < 3

42 (36%)

60 (65%)

3.4 [1.9 – 6.0]

3.0 [1.6 – 5.7]

APACHE II ≤ 15

45 (39%)

56 (61%)

2.5 [1.4 – 4.4]

2.7 [1.4 – 5.3]

Long term care

14 (12%)

9 (10%)

0.8 [0.3 – 2.0]

0.4 [0.1 – 1.0]

≥ 2 SIRS criteria

52 (44%)

53 (58%)

1.7 [1.0 – 3.0]

-

Previous antibiotics

57 (48%)

40 (44%)

0.8 [0.5 – 1.4]

-

Hospitalization > 48 hours

51 (43%)

39 (42%)

1.0 [0.6 – 1.7]

-

Mary Musgrove, PharmD1, Rachel M Kenney, PharmD2, Ronald Kendall, PharmD3, Robert Tibbetts, Ph.D. D(ABMM), F(CCM)4, Linoj Samuel, PhD., D(ABMM)5, Mike Peters, PharmD, BCPS1 and Susan Davis, PharmD6, (1)Pharmacy, Henry Ford Hospital, Detroit, MI, (2)Henry Ford Hospital, Detroit, MI, (3)Henry Ford Wyandotte Hospital, Wyandotte, MI, (4)Department of Pathology and Laboratory Medicine, Henry Ford Hospital, Detroit, MI, (5)Microbiology, Henry Ford Hospital, Detroit, MI, (6)Henry Ford Health System, CFP#3, MI

Disclosures:

M. Musgrove, None

R. M. Kenney, None

R. Kendall, None

R. Tibbetts, None

L. Samuel, None

M. Peters, None

S. Davis, Merck: Received grant through college that I'm faculty for , Grant recipient
Allergan: Speaker's Bureau , Consulting fee
Allergan: Consultant and Scientific Advisor , Consulting fee
Medicines Company: Consultant and Scientific Advisor , Consulting fee
Zavante: Consultant and Scientific Advisor , Consulting fee

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