1 / 27

Is Vancomycin Obsolete for Treating Serious Staphylococcal Infections? Part I

Is Vancomycin Obsolete for Treating Serious Staphylococcal Infections? Part I. Edward L. Goodman, MD, FACP, FIDSA, FSHEA August 26, 2009. Outline. Case presentation Are vancomycin failures increasing? Persistence of bacteremia Metastatic foci of infection Longer duration of fever

durin
Download Presentation

Is Vancomycin Obsolete for Treating Serious Staphylococcal Infections? Part I

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Is Vancomycin Obsolete for Treating Serious Staphylococcal Infections? Part I Edward L. Goodman, MD, FACP, FIDSA, FSHEA August 26, 2009

  2. Outline • Case presentation • Are vancomycin failures increasing? • Persistence of bacteremia • Metastatic foci of infection • Longer duration of fever • Vancomycin for MSSA • MIC creep of MRSA • Pharmacodynamics of antibiotics: AUIC • Consensus Guidelines 2009 • Alternatives to vancomycin • Daptomycin • Linezolid • Tigecycline • Ceftobiprole?

  3. Case PresentationMR #1283989 • 57 yo diabetic man admitted THD 2/08 with testicular pain and swelling • Required intubation, tracheostomy and was found to have MRSA in trach secretions 2/6/08 • 7/19/08 readmitted with recurrent scrotal pain and swelling • 2/2 blood cultures drawn 7/9/08 had MRSA with vancomycin MIC of 2, daptomycin MIC 1. • Could not do TEE due to obesity • Received vancomycin 7/19 till 8/18 (30 days)

  4. Case Continued • Readmit 9/8/08 with 2/2 blood cultures growing MRSA, Vanc MIC 2, dapto MIC 1 • Vancomcyin 9/10-913/08; then daptomycin (MIC 1) 9/14-10/15 (31 days) • Readmit 1/27/09 with hip abscess • 1/30/09 hip abscess drained: MRSA Vanc MIC 2 • Treated with daptomycin MIC 2 • Hospitalized for unrelated problems 7/09 • ASC in ICU 7/10/09 still positive for MRSA!

  5. Microbiology and Pharmacokinetics

  6. Comments • Clearly received adequate dose and duration of vancomycin • Yet relapsed within 3 weeks of a prolonged course • This scenario is not new, but seems to be increasing in frequency • Has MRSA become resistant to vancomycin? • MIC of 2 is within the susceptible range defined by Clinical and Laboratory Standards Institute CLSI (sensitive <=2, intermediate 4-8, resistant >=16)

  7. How Does Vancomycin Compare to Beta Lactams for MSSA? • Chang et al. Staphylococcus aureus Bacteremia. 2003 Medicine;82:333-339.

  8. Stryjewski et al. Clin Inf Dis 2007;44:190-196

  9. Does Resistance in MSSA Explain Vancomycin’s Failure? (Stryjewski et al)

  10. Are there other explanations? (Stryjewski et al)

  11. We Accept that Vancomycin is Inferior to Anti-staphylococcal Beta Lactams! • What about MRSA? • Until recently we had no other choices. • Vancomycin is cheap, relatively safe, easy to give. • But is it effective? • What factors explain its apparent increasing failures?

  12. MIC Creep • Mohr JF, Murray BE. Point: Vancomycin is Not Obsolete for the Treatment of Infections Caused by MRSA. Clin Inf Dis 2007;44:1536

  13. Pharmocodynamics: Dosing for Efficacy Peak Blood Level MIC Trough Time

  14. Parameters of antibacterial efficacy • Time above MIC (non concentration killing) - beta lactams, macrolides, clindamycin, glycopeptides • 24 hour AUC/MIC - aminoglycosides, fluoroquinolones, azalides, tetracyclines, glycopeptides, quinupristin/dalfopristin • Peak/MIC (concentration dependent killing) - aminoglycosides, fluoroquinolones, daptomycin

  15. Rybak MJ. The Pharmacokinetic and Pharmacodynamic Properties of Vancomycin. Clin Inf Dis 2006;42:S35-39

  16. Rybak et al. Vancomycin Therapeutic Guidelines. Clin Inf Dis 2009;49:325

  17. Rybak MJ. The Pharmacokinetic and Pharmacodynamic Properties of Vancomycin. Clin Inf Dis 2006;42:S35-39

  18. Take Home Messages • Rybak et al. Vancomycin Therapeutic Guidelines. Clin Inf Dis 2009;49:325

  19. Take Home Messages

  20. Take Home cont’d

  21. Key Take Home Message

  22. Alternatives to Vancomycin for Less Serious MRSA Infections • Skin and Soft Tissue • Trimethoprim-sulfa (TMP/SMX) • Doxycyline/minocycline • Clindamycin if no inducible resistance • NOT LEVOFLOXACIN! • Urinary Tract Infections (always rule out bacteremia before Rx) • TMP/SMX • Not doxycycline or minocycline or linezolid • Not adequate urinary concentration • Plain tetracycline if susceptible (94%) • Perhaps, fluoroquinolones if susceptible in vitro

  23. Alternatives to Vancomycin for Serious MRSA Infections • Daptomycin • Linezolid • Tigecycline (not for bacteremia) • Ceftobiprole (not yet FDA approved) • COME BACK 9/16/09 FOR PART II and HEAR MORE ABOUT THE ALTERNATIVES TO VANCOMYCIN!

  24. References • Chang F et al. Staphylococcus aureus Bacteremia. Medicine 2003;82:333-339. • Deresinski S. Counterpoint: Vancomycin and Staphylococcus aureus – An Antibiotic Enters Obsolescence. Clin Inf Dis 2007;44:1543-1548 • Mohr JF and Murray BE. Point: Vancomycin Is Not Obsolete for the Treatment of Infection Caused by Methicillin-Resistant Staphylococcus aureus. Clin Inf Disd 2007;44:1536-1542. • Moise-Broder PA et al. Accessory Gene Regulator Group II Polymorphism in MRSA. Clin Inf Dis 2004;38:1700-1705 • Rybak MJ et al. Vancomycin Therapeutic Guidelines: A Summary of Consensus Recommendations. Clin Inf Dis 2009;49:325-327. • Rybak MJ et al. Therapeutic monitoring of vancomycin in adult patients: A consensus review. Am J Health-Syst Pharm 2009;66:82-98. • Rybak MJ. The Pharmacokinetic and Pharmacodynamic Properties of Vancomycin. Clin Inf Dis 2006:42:S35-39. • Stryjewski ME et al. Use of Vancomycin or First-Generation Cephalosporins for the Treatment of Hemodialysis-Dependent Patients with Methicillin-Susceptible Staphylococcus aureus Bacteremia. Clin Inf Dis 2007; 44:190-196.

More Related