1 / 7

Antimicrobial Susceptibility Tests

Antimicrobial Susceptibility Tests. Measure either MIC or zone diameter Report result as S, I or R Clinical utility depends on predictive value (PV) PV rarely reported in clinical trials Can we make it a reporting standard? If it is poor, can we improve it?. C. F. Clinical Response. S.

edan-knight
Télécharger la présentation

Antimicrobial Susceptibility Tests

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. Antimicrobial Susceptibility Tests • Measure either MIC or zone diameter • Report result as S, I or R • Clinical utility depends on predictive value (PV) • PV rarely reported in clinical trials • Can we make it a reporting standard? • If it is poor, can we improve it?

  2. C F Clinical Response S TS FS AS R FR TR AR A S T AC AF Predictive Value of AST • PV = T / (T+F) • PVs = TS / (TS+FS) = TS / AS • PVr = TR / (TR+FR) TR / AR

  3. 100 Percent Clinical Success 50 0 NitFur Cefotet Cefotax1 Cefotax2 CipFlox1 CipFlox2 90 94 93 92 89 91 S 73 96 78 83 90 79 I 50 77 65 63 86 62 R Poupard JA, Walsh RA, Kleger B. Antimicrobial Susceptibility Testing. New York: Plenum, 1994; 15-25.

  4. Predictive Values of AST PVs PVr 100 90 80 70 60 50 40 30 20 10 0 NitFur CefTet CefTax1 CefTax2 CipFlx1 CipFlx2

  5. Antimicrobial Susceptibility Testing • Isolated pathogen- is it likely to be the cause? • Site of infection- expected antimicrobial concentration? • MIC or zone diameter • Immune status of the patient • Dose, frequency and route of the drug [Evans ER et al. NEJM 1998 Jan 22; 338:232-8.].]

  6. Clinically Useful Report If P = probability of cure with an antibiotic, then P = aMIC + bg/mL + c  IS Where g  Dose, Route, Frequency, PK andIS = immune status

  7. Antibiotic Penicillin G Sulfadimidine Nitrofurantoin Coamoxiclav Ciprofloxacin P of Success 0.40 0.80 0.90 0.85 0.90 Clinically Useful ReportSpecimen:UrineIsolate: E. coli

More Related