CLSI guidelines Antimicrobial sensitivity test

CLSI guidelines for antimicrobial sensitivity test

1. CLSI AST, 2023 Cascade reporting

2. Enterococcus spp

3. Note Ampicillin susceptibility (S) test predicts activity of amoxicillin. Amp results may be used to predict S to Augmentin, amp-sulbactam, and piperacillin-tazobactam among non- β -producing enterococci Amp susceptibility may be used to predict imipenem susceptibility if the species confirmed to be E. faecalis Enterococci susceptible to penicillin are predictable susceptible to ampicillin, amox, amp-sulbactam, and piperacillin-tazobactam among non- β -producing enterococci However, susceptibility to ampicillin does not guarantee susceptibility to penicillin. If penicillin results are required, testing penicillin is needed

4. Note cont.. Rx: Combination therapy with high dosage parenteral amp, amox, penicillin or vancomycin(for susceptible strain only) plus an aminoglycoside is usually indicated for serious enterococci infections such as endocarditis, unless high-level resistance to both gentamicin and streptomycin is documented. Such combination are predicted to results in synergistic killing of enterococci * Tested for urine only b Organisms that are susceptible to tetracycline are also susceptible to doxycycline . Some organisms are intermediate or resistant to tetracycline may be susceptible to doxycycline

5. Streptococcus pneumoniae

6. Note a Susceptibility and resistant to clarithromycin and azithromycin can be predicted by testing erythromycin b Nor routinely reported on organisms isolated from urinary tract c Penicillin and Cefotaxime , ceftriaxone or meropeneme should be tested for reliable MIC method (see M07) and reported rottenly with S. pneumoniae isolated from CSF. Such isolates can also be tested for Vancomycin using MIC or disc diffusion method d MIC test only. Disc diffusion method is unreliable e Organisms that are susceptible to tetracycline are also susceptible to doxycycline . e RX: Rifampicin should not used alone for antimicrobial therapy