ANTIBIOTIC SUSCEPTIBILITY TESTING BY THE CDS METHOD Tles Only Online Edition Septemer 2009 S.M. Bell, B.J. Gtus, J.N. Phm, G.T. Fisher The Antiiotic Reference Lortory Deprtment of Microiology The Prince of Wles Hospitl South Estern Are Lortory Services Rndwick NSW 2031 Austrli Tel: (02) 9382 9046/9053 Fx: (02) 9382 9098 E-mil: sydney.ell@sesihs.helth.nsw.gov.u rrie.gtus@sesihs.helth.nsw.gov.u jenette.phm@sesihs.helth.nsw.gov.u Wesite: http://we.med.unsw.edu.u/cdstest South Estern Are Lortory Services Online Edition Septemer 2009 1
Contents Contents CONTENTS...2 TABLES...2 10. TABLES...3 A GUIDE TO THE USE OF THE TABLES...3 10.1. CALIBRATIONS...4 10.2. SURROGATE DISCS...12 10.3. QUALITY ASSURANCE...16 10.4. TESTING AND REPORTING Β-LACTAM ANTIBIOTICS...21 Tles Tle 10.1.. Clirtions: Grm Positive Orgnisms 4 Tle 10.1.. Clirtions: Grm Negtive Orgnisms 7 Tle 10.1.c. Clirtions: Aneroic Orgnisms. 11 Tle 10.1.d. Clirtions: Yest. 11 Tle 10.2.. Surrogte disc testing: Grm Positive Orgnisms 12 Tle 10.2.. Surrogte disc testing: Grm Negtive Orgnisms 14 Tle 10.3.. Reference strins: Grm Positive Orgnisms 16 Tle 10.3.. Reference strins: Grm Negtive Orgnisms 17 Tle 10.3.c. Reference strins: Aneroic Orgnisms 20 Tle 10.3.d. Reference strins: Yest 20 Tle 10.4.. A guide to the testing nd reporting of β-lctm ntiiotics for Grmnegtive orgnisms. 21 Online Edition Septemer 2009 2
Chpter 10. Tles 10. Tles A Guide to the Use of the Tles There re 4 sets of tles contining informtion essentil for the performnce of the CDS Test. These tles re intended for oth Clinicl nd Veterinry lortories. Antiiotics used in veterinry medicine only re flgged. Clirtion tles 1, 1, 1c, & 1d collectively summrise much of the sic informtion used in the CDS Test. They list ll the orgnisms nd ntimicroils tested y the method, the medi used, conditions of incution, disc potencies, cut off sizes for unusul nnulr rdii nd the MICs for susceptile strins (rekpoints). The tles re updted regulrly nd opertors should ensure tht they re using the ltest versions of these tles. It is most importnt to py prticulr ttention to the footnotes included with ech tle s these highlight exceptions, restrictions nd some specific directions. For orgnisms not included in the Tle of Clirtions, extrpolte the testing from tht estlished for similr orgnisms. Surrogte Disc Testing tles 2 nd 2, list those ntimicroils where the susceptiility cn e inferred from the results otined with closely relted gent, the surrogte disc. The tle is rrnged ccording to cteril species nd the reltionship etween the ntimicroils is vlid only for the species indicted. This tle is lso updted regulrly s dt re ccumulted which either invlidte the reltionship or enle us to dd gents to the list. Lortories my find it useful to include comment on the susceptiility report tht the result reported with prticulr ntimicroil indictes the susceptiility to nother. Qulity ssurnce tles 3, 3, 3c & 3d list the 13 reference strins, the medi, the incution conditions of testing nd the expected rnge of zone sizes oserved with ech disc of stted potency. The footnotes explin how the cceptle rnges of zone sizes were derived nd recommend the indictions for nd the frequency of testing the reference strins. Tle 4 is guide through the mze of testing nd reporting the susceptiility of Grm-negtive eroic species to β-lctm ntiiotics. The production of one or more β-lctmses is n importnt nd common mechnism of resistnce in these species, ut for severl resons, resistnce my e difficult or impossile to demonstrte y the usul methods of ntiiotic susceptiility testing. The tle sets out, in some detil, those species where resistnce should e ssumed on the sis of previous documenttion of the presence of stle mechnism of resistnce nd those where susceptiility cn e relily demonstrted y the disc test. This tle lso relies hevily on the footnotes to drw ttention to exceptions nd specil circumstnces. Online Edition Septemer 2009 3
Chpter 10. Tles 10.1. Clirtions Tle 10.1.. Clirtions: Grm Positive Orgnisms Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Antiiotic Corynecterium species (Blood Sensitest, CO2, 35-37 C) Ampicillin c 5 2 Benzylpenicillin 0.5 u 0.125 Chlormphenicol 30 8 Ciprofloxcin 2.5 1 Clindmycin n 2 0.5 Erythromycin 5 0.5 Fusidic cid 2.5 0.5 Mrofloxcin k 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Quinupristin/Dlfopristin 15 2 Rifmpicin 1 0.5 Teicoplnin 15 2 mm 8 Tetrcycline 10 4 Tigecycline 15 1 Vncomycin 5 2 mm 4 Enterococci (Blood Sensitest, CO 2, 35-37 C) Ampicillin d 5 d 4 mm d 4 Chlormphenicol 30 4 mm 8 Gentmicin 200 256 Linezolid 10 4 Mrofloxcin k 5 2 Nitrofurntoin e 200 4 mm 64 Quinupristin/Dlfopristin f 15 2 Streptomycin 300 4 mm 512 Teicoplnin 15 2 mm 8 Tigecycline 15 1 Vncomycin 5 (See foot note) g 4 Listeri species (Blood Sensitest, CO 2, 35-37 C) Ampicillin 5 1 Co-trimoxzole 25 0.5/9.5 Gentmicin 10 1 The stndrd 6 mm cut-off pplies where no exception hs een specified. Slow growers re incuted for 48h. c If Corynecterium species is resistnt to enzylpenicillin 0.5 units, test mpicillin 5 µg. d Perform nitrocefin sed test to detect β lctmse ctivity if the zone of inhiition hs shrp edge nd n nnulr rdius > 4 mm. β Lctmse positive isoltes re reported s resistnt. e For testing urine isoltes only. f Enterococcus feclis is intrinsiclly resistnt to Pristinmycin nd Quinupristin/Dlfopristin. g A zone of inhiition with hzy edge indictes low level resistnce to Vncomycin (VnB type), irrespective of the size of the inhiitory zone. The hzy edge will e more evident if the plte reincuted for totl of 48. k Antiiotic clirted for veterinry medicine. n Isoltes with inducile clindmycin resistnce (imlsb phenotype) will hve lrge zone to clindmycin, ut should e reported s resistnt. Inducile clindmycin resistnce cn e detected s descried in section 4.8 of the CDS mnul. Online Edition Septemer 2009 4
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Positive Orgnisms cont. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Antiiotic Nocdi species (Blood Sensitest, 5% Air, 35-37 C) Amikcin 30 8 Ciprofloxcin 2.5 1 Clrithromycin 5 0.5 Co-trimoxzole 25 2/38 Gentmicin 10 2 Imipenem 10 4 Linezolid 10 2 Tigecycline 15 2 Stphylococci (Sensitest, Air 35-37 C) Ampicillin h 5 0.5 Benzylpenicillin i 0.5 u 0.06 Cefoxitin j 10 4 Cephlexin h 100 16 Chlormphenicol 30 8 Ciprofloxcin 2.5 1 Clindmycin n 2 0.5 Co-trimoxzole 25 1/19 Erythromycin 5 0.5 Fusidic cid 2.5 0.5 Gentmicin 10 1 Knmycin 50 8 Linezolid 10 4 Mrofloxcin k 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Mupirocin 5 2 Neomycin k 30 4 mm 8 Nitrofurntoin e 200 32 Novoiocin k 5 1 Oxcillin l 1 0.25 Quinupristin/Dlfopristin 15 2 Rifmpicin 1 0.5 Sulphfurzole 300 64 Teicoplnin 15 2 mm 8 Tetrcycline 10 4 Tigecycline 15 1 Trimethoprim 5 4 Vncomycin 5 2 mm 4 The stndrd 6 mm cut-off pplies where no exception hs een specified. e For testing urine isoltes only. h For testing Stphylococcus sprophyticus only. i Not for testing Stphylococcus sprophyticus. j For testing Stphylococcus ureus only. k Antiiotic clirted for veterinry medicine. l For testing cogulse-negtive stphylococci (except Stphylococcus sprophyticus). n Isoltes with inducile clindmycin resistnce (imlsb phenotype) will hve lrge zone to clindmycin, ut should e reported s resistnt. Inducile clindmycin resistnce cn e detected s descried in section 4.8 of the CDS mnul. Online Edition Septemer 2009 5
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Positive Orgnisms cont. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Antiiotic Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Streptococci & Erysipelothrix species (Blood Sensitest, CO 2, 35-37 C) m Ampicillin m 5 4 mm 2 Benzylpenicillin 0.5 u 0.125 Cefotxime 0.5 0.25 Cefotxime m 5 2 Ceftrixone 0.5 0.25 Ceftrixone m 5 2 Chlormphenicol 30 8 Clindmycin n 2 0.5 Co-trimoxzole 25 0.5/9.5 Erythromycin 5 0.5 Mrofloxcin k 5 2 Moxifloxcin/Gtifloxcin 2.5 4 mm 1 Nitrofurntoin e 200 32 Quinupristin/Dlfopristin 15 2 Rifmpicin 1 0.5 Teicoplnin 15 2 mm 8 Tetrcycline 10 4 Tigecycline 15 1 Vncomycin 5 2 mm 4 The stndrd 6 mm cut-off pplies where no exception hs een specified. e For testing urine isoltes only. k Antiiotic clirted for veterinry medicine. m NOT for testing Streptococcus pneumonie from CSF. If Streptococcus pneumonie or ny other Streptococcus species from site other thn CSF is resistnt to enzylpenicillin 0.5 units, cefotxime 0.5 µg or ceftrixone 0.5 µg then test mpicillin 5 µg, cefotxime 5 µg nd ceftrixone 5 µg. n Isoltes with inducile clindmycin resistnce (imlsb phenotype) will hve lrge zone to clindmycin, ut should e reported s resistnt. Inducile clindmycin resistnce cn e detected s descried in section 4.8 of the CDS mnul. Online Edition Septemer 2009 6
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Negtive Orgnisms Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Antiiotic Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Acinetocter species, Enteroctericee & Virioncee (Sensitest, ir, 35-37 C) Amikcin 30 4 mm c 16 c Ampicillin 25 8 Aprmicin d 15 8 Augmentin e 60 16/8 Aztreonm 30 8 Cefzolin 30 16 Cefepime 10 2 Cefotxime 5 1 Cefotetn 30 8 Cefoxitin 30 8 Cefpirome 10 2 Cefpodoxime 10 2 Ceftzidime 10 4 Ceftrixone 5 1 Cefuroxime 30 8 Cephlexin 100 16 Chlormphenicol 30 8 Ciprofloxcin 2.5 1 Enoxcin 10 4 Ertpenem f 10 4 Gentmicin 10 4 mm 2 Imipenem 10 4 Knmycin 50 8 Mrofloxcin d 5 2 Meropenem 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Nlidixic cid g 30 4 Neomycin d 30 4 mm 8 Nitrofurntoin g 200 32 Norfloxcin g 10 4 Polymyxin B 300 u 4 mm 1 Spectinomycin d 25 32 Streptomycin d 25 16 Sulphfurzole 300 64 Tzocin e 55 16/2 Tetrcycline 10 4 mm 4.0 Tigecycline 15 1 Timentin e 85 32/2 Tormycin 10 4 mm 2 Trimethoprim 5 4 The stndrd 6 mm cut-off pplies where no exception hs een specified. Yersini enterocolitic is incuted in ir t 30 C. c Revised clirtion, 2006. d Antiiotic clirted for veterinry medicine. e If n ESBL is present, report Augmentin, Timentin nd Tzocin for isoltes from urine only. f Acinetocter species re considered resistnt to ertpenem. g For testing urinry isoltes only. Online Edition Septemer 2009 7
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Negtive Orgnisms cont. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Antiiotic Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Brnhmell ctrrhlis (Morxell ctrrhlis) (Blood Sensitest, 5% CO2, 35-37 C) Benzylpenicillin 0.5 u 0.25 Cefclor 30 4 Cefpodoxime 10 2 Cefuroxime 30 4 Chlormphenicol 10 4 Ciprofloxcin 2.5 1 Co-trimoxzole 25 1/19 Erythromycin 5 0.5 Mrofloxcin d 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Tetrcycline 10 4 Cmpylocter species (Blood Sensitest, microerophilic, 42 C) Ciprofloxcin 2.5 1 Erythromycin 5 4 mm 0.5 Gentmicin 10 1 Tetrcycline 10 4 Hemophilus species (HTM gr h, 5% CO2, 35-37 C) Ampicillin 5 1 Augmentin 15 2/1 Cefclor 30 4 Cefotxime 0.5 0.25 Cefotxime 5 1 Cefpodoxime 10 2 Ceftrixone 0.5 0.25 Ceftrixone 5 1 Cefuroxime 30 4 Chlormphenicol 10 2 Ciprofloxcin 2.5 1 Co-trimoxzole 25 1/19 Mrofloxcin d 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Tetrcycline 10 4 Helicocter pylori (Chocolte Columi Blood Agr, microerophilic, 35-37 C) Amoxycillin 2 1 Ciprofloxcin 2.5 1 Erythromycin i 5 0.5 Metronidzole 5 4 Rifmpicin j 5 2 Tetrcycline 10 4 The stndrd 6 mm cut-off pplies where no exception hs een specified. d Antiiotic clirted for veterinry medicine. h Hemophilus Test Medium Bse contining 15 mg/l of freshly prepred hemtin nd NAD. i Erythromycin 5 µg is the surrogte disc for reporting the susceptiility to clrithromycin. The MIC of clrithromycin for susceptile strins is 0.5 mg/l. j Rifmpicin 5 µg is the surrogte disc for reporting the susceptiility to rifutin. Online Edition Septemer 2009 8
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Negtive Orgnisms cont. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Antiiotic Disc potency (µg) Exception to the stndrd interprettion Neisseri gonorrhoee k (Chocolte Columi Blood Agr, 5% CO2, 35-36 C, humidity > 80%) Benzylpenicillin 0.5 u MIC (mg/l) Susceptile k > 9 0.03 l Less susceptile k 3 9 0.06 0.5 l Resistnt k < 3 1 l Ceftrixone 0.5 Susceptile k > 9 < 0.03 l Non susceptile k 5 9 0.03 0.25 l Resistnt k Ciprofloxcin/Nlidixic cid CIP 1 / NA 30 CIP 1 NA 30 Susceptile k > 6 > 6 0.03 n Less susceptile k,m > 6 0 m 0.06 0.5 n Resistnt k,m 6 0 m 1 n Spectinomycin 100 Susceptile k 6 64 Less susceptile k Resistnt k 0 128 Neisseri meningitidis (Blood Sensitest, 5% CO2, 35-37 C) Benzylpenicillin 0.5 u 4 mm 0.25 Cefotxime 0.5 0.25 Ceftrixone 0.5 0.25 Chlormphenicol 10 2 Ciprofloxcin 2.5 1 Rifmpicin 1 0.5 The stndrd 6 mm cut-off pplies where no exception hs een specified. k Neisseri gonorrhoee sensitivity interprettion: Susceptile A cure is expected following tretment with stndrd doses. Less susceptile Quinolone gents: A cure would e expected following high orl dose regimens e.g. 500 mg ciprofloxcin, ut tretment filure from lower doses. Penicillin Group: A cure would e expected with the stndrd regimens used to tret mle urethrl gonorrhoe (e.g. single orl dose of 3g moxycillin), ut tretment filure my occur for other infected sites e.g. endocervix, phrynx nd rectum. Non susceptile Reduced zone size to Ceftrixone. Clinicl significnce is currently uncertin. Resistnt There is high proility of tretment filure using current dose recommendtions. l MIC determined y douling dilution gr plte technique. m On rre occsions (< 0.001% of isoltes) smll zone to Nlidixic Acid my e oserved in ssocition with decresed ciprofloxcin zone sizes. If the findings re confirmed on repet testing the isolte should e reported s less susceptile or resistnt ccording to the ciprofloxcin zone size nd the isolte referred for MIC testing. n MICs for ciprofloxcin. Online Edition Septemer 2009 9
Chpter 10. Tles Tle 10.1.. Clirtions: Grm Negtive Orgnisms cont. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Antiiotic Psteurell species (Blood Sensitest, 5% CO2, 35-37 C) Ampicillin o 5 2 Benzylpenicillin 0.5 u 4 mm 0.25 Ciprofloxcin 2.5 1 Mrofloxcin d 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Tetrcycline 10 4 Pseudomons species, Burkholderi species & Chryseocterium species (Sensitest, ir, 35-37 C) Amikcin 30 4 mm 16 Augmentin p 60 8/4 Aztreonm 30 8 Cefepime 10 2 Cefpirome 10 2 Ceftzidime 10 4 Ciprofloxcin 2.5 1 Ertpenem 10 4 Gentmicin 10 4 mm 4 Imipenem 10 4 Mrofloxcin d 5 2 Meropenem 5 2 Moxifloxcin/Gtifloxcin 2.5 1 Norfloxcin g 10 4 Pipercillin 50 16 Polymyxin B 300 u 4 mm 1 Sulphfurzole 300 64 Tzocin 55 16/2 Ticrcillin 75 32 Timentin 85 32/2 Tormycin 10 4 mm 4 Trimethoprim 5 4 Stenotrophomons mltophili q (Sensitest, ir, 35-37 C) Sulphfurzole q 300 64 The stndrd 6 mm cut-off pplies where no exception hs een specified. d Antiiotic clirted for veterinry medicine. g For testing urine isoltes only o Psteurell multocid is tested ginst mpicillin 5 µg nd NOT enzylpenicillin 0.5 units. p Burkholderi pseudomllei is usully susceptile to Augmentin nd cn e tested ginst this ntiiotic. q See Section 5.11 of the CDS mnul for notes on testing ntiiotic susceptiilities of Sulphfurzole resistnt S. mltophili. Online Edition Septemer 2009 10
Chpter 10. Tles Tle 10.1.c. Clirtions: Aneroic Orgnisms. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Antiiotic Aneroic orgnisms (Supplemented Brucell Medium Bse, neroic, 35-37 C) c Augmentin 3 4 mm 1/2 Benzylpenicillin 0.5 u 0.25 Cefoxitin 10 4 Clindmycin 2 4 mm 0.5 Meropenem 5 2 Metronidzole 5 4 mm 2 Moxifloxcin 2.5 4 mm 2 Tzocin 55 8/2 Timentin 85 32/2 The stndrd 6 mm cut-off pplies where no exception hs een specified. c Slow growers should e incuted for 48 hrs. Brucell Medium Bse contining 5% defirinted horse lood, hemin 5 mg/l nd vitmin K 1 mg/l. Tle 10.1.d. Clirtions: Yest. Antiiotics, disc potencies, nnulr rdii nd MIC for susceptile strins, medi nd incution conditions. Disc potency (µg) Exception to the stndrd interprettion MIC (mg/l) Antiiotic Yests (Csitone complex medium, ir, 30 C) Amphotericin B 10 4 mm 0.125 Cspofungin 5 2 mm 2.0 Fluconzole 25 6 mm 16 Itrconzole 10 4 mm 1.0 Voriconzole 1 6 mm 1.0 The stndrd 6 mm cut-off pplies where no exception hs een specified. Online Edition Septemer 2009 11
Chpter 10. Tles 10.2. Surrogte Discs Tle 10.2.. Surrogte disc testing: Grm Positive Orgnisms Antiiotics tht cn e reported sed on susceptiility results otined with surrogte disc. Antiiotic reported Surrogte disc used Disc potency (µg) Corynecterium species Amoxycillin/Ampicillin/Penicillin V Benzylpenicillin 0.5 u Azithromycin/Clrithromycin/Roxithromycin Erythromycin 5 Cefovecin /Ceftiofur /other Cephlosporins Benzylpenicillin 0.5 u Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Lincomycin Clindmycin 2 Norfloxcin c /Ofloxcin Ciprofloxcin 2.5 Pristinmycin Quinupristin/Dlfopristin 15 Tetrcyclines Tetrcycline 10 Tylosin Erythromycin 5 Enterococci Amoxycillin/Benzylpenicillin Ampicillin 5 Pristinmycin f Quinupristin/Dlfopristin 15 Listeri species Amoxycillin/Benzylpenicillin Ampicillin 5 Stphylococci (except S. sprophyticus from urine) Amoxycillin/Ampicillin/Penicillin V Benzylpenicillin 0.5 u Augmentin Oxcillin d /Cefoxitin e 1 d / 10 e Azithromycin/Clrithromycin/Roxithromycin Erythromycin 5 Cefovecin /Ceftiofur /other Cephlosporins Oxcillin d /Cefoxitin e 1 d / 10 e Cloxcillin/ Dicloxcillin/ Flucloxcillin Oxcillin d /Cefoxitin e 1 d / 10 e Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Lincomycin Clindmycin 2 Norfloxcin c /Ofloxcin Ciprofloxcin 2.5 Pristinmycin Quinupristin/Dlfopristin 15 Sulphonmides Sulphfurzole 300 Tetrcyclines Tetrcycline 10 Tylosin Erythromycin 5 Stphylococcus sprophyticus from urine Amoxycillin/Benzylpenicillin/Penicillin V Ampicillin 5 Augmentin Cephlexin 100 Cefovecin /Ceftiofur /other Cephlosporins Cephlexin 100 Cloxcillin/Dicloxcillin/Flucloxcillin Cephlexin 100 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Norfloxcin c /Ofloxcin Ciprofloxcin 2.5 Sulphonmides Sulphfurzole 300 Tetrcyclines Tetrcycline 10 c d e f Antiiotic used in veterinry medicine only. Ceftzidime is inctive ginst Grm-positive orgnisms. Reporting of norfloxcin is for urine isoltes only. Oxcillin is used for testing cogulse-negtive stphylococci (except Stphylococcus sprophyticus) only. Cefoxitin is used for testing Stphylococcus ureus only. Enterococcus feclis is intrinsiclly resistnt to Pristinmycin nd Quinupristin/Dlfopristin. Online Edition Septemer 2009 12
Chpter 10. Tles Tle 10.2.. Surrogte disc testing: Grm Positive Orgnisms cont. Antiiotics tht cn e reported sed on susceptiility results otined with surrogte disc. Antiiotic reported Surrogte disc used Disc potency (µg) Streptococci g Amoxycillin/Ampicillin/Penicillin V Benzylpenicillin 0.5 u Amoxycillin/Benzylpenicillin Ampicillin h 5 Azithromycin/Clrithromycin/Roxithromycin Erythromycin 5 Cefovecin /Ceftiofur Benzylpenicillin 0.5 u Cephlosporins (except ceftiofur) Cefotxime/Ceftrixone 0.5 Lincomycin Clindmycin 2 Pristinmycin Quinupristin/Dlfopristin 15 Tetrcyclines Tetrcycline 10 Tylosin Erythromycin 5 Antiiotic used in veterinry medicine only. g For streptococci groups A, B, C, G nd Streptococcus nginosus, the susceptiility to enzylpenicillin, mpicillin, moxycillin nd cephlosporin ntiiotics (except ceftzidime) is extrpolted from the testing of enzylpenicillin 0.5 units. h NOT for testing Streptococcus pneumonie from CSF. Test if isolte is resistnt to enzylpenicillin 0.5 units, cefotxime 0.5 mg or ceftrixone 0.5 mg. Online Edition Septemer 2009 13
Chpter 10. Tles Tle 10.2.. Surrogte disc testing: Grm Negtive Orgnisms Antiiotics tht cn e reported sed on susceptiility results otined with surrogte disc. Antiiotic reported Surrogte disc used Disc potency (µg) Acinetocter, Enteroctericee & Virioncee species Amoxycillin Ampicillin 25 Cefovecin /Ceftiofur Cefzolin 30 Cephlothin Ampicillin 25 Ceftrixone Cefotxime 5 Cefotxime Ceftrixone 5 Co-trimoxzole c Sulphfurzole 300 Co-trimoxzole c Trimethoprim 5 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Ofloxcin Ciprofloxcin 2.5 Pipercillin Ampicillin 25 Sulphonmides Sulphfurzole 300 Tetrcyclines Tetrcycline 10 Ticrcillin Ampicillin 25 Brnhmell ctrrhlis (Morxell ctrrhlis) Azithromycin/Clrithromycin/Roxithromycin Erythromycin 5 Amoxycillin/Ampicillin/Penicillin V Benzylpenicillin 0.5 u Augmentin Cefuroxime/Cefclor 30 Cefovecin /Ceftiofur Cefuroxime/Cefclor 30 Cephlosporins Cefuroxime/Cefclor 30 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Ofloxcin Ciprofloxcin 2.5 Tetrcyclines Tetrcycline 10 Cmpylocter species Enrofloxcin /Orifloxcin Ciprofloxcin 2.5 Tetrcyclines Tetrcycline 10 Hemophilus influenze/hemophilus species Amoxycillin Ampicillin 5 Cefepime Cefotxime/Ceftrixone 0.5 Cefotxime Ceftrixone 0.5 Cefpirome Cefotxime/Ceftrixone 0.5 Ceftzidime Cefotxime/Ceftrixone 0.5 Cefovecin /Ceftiofur Cefuroxime/Cefclor 30 Ceftrixone Cefotxime 0.5 Cephlexin Cefuroxime/Cefclor 30 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Ofloxcin Ciprofloxcin 2.5 Tetrcyclines Tetrcycline 10 Helicocter pylori Clrithromycin Erythromycin 5 Rifutin Rifmpicin 5 c Antiiotic used in veterinry medicine only. Not for Acinetocter species. Resistnce to co-trimoxzole is indicted y resistnce to oth sulphfurzole nd trimethoprim. Online Edition Septemer 2009 14
Chpter 10. Tles Tle 10.2.. Surrogte disc testing: Grm Negtive Orgnisms cont. Antiiotics tht cn e reported sed on susceptiility results otined with surrogte disc. Antiiotic reported Surrogte disc used Disc potency (µg) Neisseri meningitidis Ampicillin/Amoxycillin Benzylpenicillin 0.5 u Cefotxime Ceftrixone 0.5 Cefovecin /Ceftiofur Benzylpenicillin 0.5 u Ceftrixone Cefotxime 0.5 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Psteurell species Amoxycillin/Benzylpenicillin Ampicillin 5 Ampicillin/moxycillin Benzylpenicillin d 0.5 u Cefovecin /Ceftiofur Ampicillin 5 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Ofloxcin Ciprofloxcin 2.5 Tetrcyclines Tetrcycline 10 Pseudomons species, Burkholderi species & Chryseocterium species Azlocillin Pipercillin 50 Colistin Polymyxin B 300 u Co-trimoxzole c Trimethoprim 5 Co-trimoxzole c Sulphfurzole 300 Enrofloxcin /Orifloxcin Moxifloxcin 2.5 Norfloxcin c /Ofloxcin Ciprofloxcin 2.5 Stenotrophomons mltophili Co-trimoxzole Sulphfurzole 300 Antiiotic used in veterinry medicine only. c Resistnce to co-trimoxzole is indicted y resistnce to oth sulphfurzole nd trimethoprim. d Psteurell multocid is tested ginst mpicillin 5 µg nd NOT enzylpenicillin 0.5 units. Online Edition Septemer 2009 15
Chpter 10. Tles 10.3. Qulity Assurnce Tle 10.3.. Reference strins: Grm Positive Orgnisms Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Enterococcus feclis ACM 5184 (Blood Sensitest, CO 2 35 C) Ampicillin 5 5.9 9.2 Chlormphenicol 30 6.3 8.7 Gentmicin 200 6.6 9.9 Linezolid 10 6.6 9.0 Nitrofurntoin 200 6.1 8.7 Streptomycin 300 5.4 7.9 Tigecycline 15 6.6 9.5 Teicoplnin 15 3.1 5.3 Vncomycin 5 2.0 3.7 Stphylococcus ureus ACM 5190 (Sensitest, ir 35 C) Amoxycillin c 2 9.1 11.9 Ampicillin 5 12.1 18.1 Benzylpenicillin 0.5 u 8.7 13.5 Cefoxitin 10 7.1 10.1 Cephlexin 100 10.7 15.5 Chlormphenicol 30 7.8 11.4 Ciprofloxcin 2.5 9.2 12.4 Clrithromycin 5 9.4 11.8 Clindmycin 2 8.5 12.9 Co-trimoxzole 25 10.1 13.3 Erythromycin 5 8.0 10.8 Fusidic cid 2.5 8.6 12.6 Gtifloxcin 2.5 10.1 14.9 Gentmicin 10 6.6 9.4 Knmycin 50 7.8 9.6 Linezolid 10 7.9 13.1 Mrofloxcin d 5 8.9 11 Moxifloxcin 2.5 10.9 14.5 Mupirocin 5 7.4 12.2 Neomycin d 30 8.1 12.9 Nitrofurntoin 200 6.7 10.3 Novoiocin d 5 6.1 12.5 Oxcillin 1 7.4 10.4 Quinupristin/Dlfopristin 15 9.2 12.4 Rifmpicin 1 9.3 12.5 Rifmpicin c 5 12.7 15 Sulphfurzole 300 9.3 13.7 Teicoplnin 15 3.4 6.1 Tetrcycline 10 11.3 14.4 Tigecycline 15 10.3 13.2 Trimethoprim 5 8.5 11.3 Vncomycin 5 2.8 4.9 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. c The 2 µg moxycillin nd 5 µg Rifmpicin discs re used for the susceptiility testing of H. pylori only. d Antiiotic used in veterinry medicine only. Online Edition Septemer 2009 16
Chpter 10. Tles Tle 10.3.. Reference strins: Grm Positive Orgnisms cont. Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Streptococcus pneumonie ACM 5191 (Blood Sensitest, 5% CO 2, 35 37 C) Ampicillin 5 10.8 15.2 Benzylpenicillin 0.5 u 8.3 14.8 Cefotxime 0.5 9.3 14.8 Cefotxime 5 10.9 15.3 Ceftrixone 0.5 9.1 14.3 Ceftrixone 5 11.5 15.2 Chlormphenicol 30 8.0 13.2 Clindmycin 2 7.1 9.9 Co-trimoxzole 25 7.0 9.2 Erythromycin 5 7.1 12.9 Gtifloxcin 2.5 5.6 8.4 Moxifloxcin 2.5 5.6 8.6 Quinupristin/Dlfopristin 15 6.4 9.2 Rifmpicin 1 7.5 10.8 Teicoplnin 15 5.1 8.0 Tetrcycline 10 9.5 11.5 Tigecycline 15 9.7 12.6 Vncomycin 5 5.1 8.6 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. Tle 10.3.. Reference strins: Grm Negtive Orgnisms Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Bcteroides frgilis ACM 5196 c (Blood Sensitest, neroic, 35-37 C) Metronidzole 5 7.1 13.5 Cmpylocter jejuni ACM 5183 (Blood Sensitest, microerophilic, 42 C) Ciprofloxcin 2.5 9.2 16.9 Erythromycin 5 6.4 12.4 Gentmicin 10 7.0 11.0 Tetrcycline 10 14.5 18.6 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. c Bcteroides frgilis (ACM 5196) my e used s the reference strin when testing H. pylori ginst metronidzole. When testing neroic orgnisms, Clostridium perfringens (ACM 5240) should e used s the reference orgnism. Online Edition Septemer 2009 17
Chpter 10. Tles Tle 10.3.. Reference strins: Grm Negtive Orgnisms cont. Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Escherichi coli ACM 5185 d (Sensitest, ir, 35 37 C) Amikcin 30 6.7 10.3 Ampicillin 25 7.5 10.7 Aprmicin d 15 5.3 7.9 Aztreonm 30 13.7 15.9 Cefzolin 30 6.7 12.7 Cefepime 10 11.9 15.3 Cefotxime 5 9.7 13.7 Cefotetn 30 11.9 14.8 Cefoxitin 30 9.8 13.0 Cefpirome 10 11.9 14.6 Cefpodoxime 10 10.3 12.7 Ceftzidime 10 9.3 14.1 Ceftrixone 5 10.5 14.3 Cefuroxime 30 8.3 11.1 Cephlexin 100 6.9 10.9 Chlormphenicol 30 8.7 11.9 Ciprofloxcin 2.5 12.4 15.8 Gtifloxcin 2.5 11.2 14.8 Enoxcin 10 9.7 15.7 Ertpenem 10 12.1 16.1 Gentmicin 10 6.2 9.4 Imipenem 10 10.3 13.5 Knmycin 50 6.2 11.8 Mrofloxcin e 5 13.2 15.3 Meropenem 5 11.0 14.4 Moxifloxcin 2.5 10.0 13.4 Nlidixic cid 30 8.9 12.1 Neomycin e 30 6.0 8.6 Nitrofurntoin 200 6.3 9.5 Norfloxcin 10 10.4 16.4 Polymyxin B 300 u 5.1 7.5 Spectinomycin d 25 5.0 7.8 Streptomycin e 25 6.2 7.8 Sulphfurzole 300 6.7 10.7 Tetrcycline 10 4.5 8.6 Tigecycline 15 9.7 12.6 Tormycin 10 6.4 8.4 Trimethoprim 5 8.8 13.6 Escherichi coli ACM 5186 (Sensitest, ir, 35-37 C) Augmentin 60 6.4 9.6 Timentin 85 6.0 8.4 Tzocin 55 7.4 9.2 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. d If ntiiotic discs re tested with Escherichi coli ACM 5185, there is no need to test these ginst Pseudomons eruginos ACM 5189 s well nd vice vers. e Antiiotic used in veterinry medicine only Online Edition Septemer 2009 18
Chpter 10. Tles Tle 10.3.. Reference strins: Grm Negtive Orgnisms cont. Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Hemophilus influenze ACM 5187 (HTM f gr, 5% CO 2, 35-37 C) Ampicillin 5 7.0 11.1 Cefclor 30 8.1 12.1 Cefotxime 0.5 9.2 12.8 Cefpodoxime 10 10.9 14.1 Ceftrixone 0.5 9.1 12.9 Cefuroxime 30 8.3 12.8 Chlormphenicol 10 11.1 14.3 Ciprofloxcin 2.5 11.1 15.9 Co-trimoxzole 25 9.0 12.5 Gtifloxcin 2.5 13.5 17.1 Moxifloxcin 2.5 10.6 15.2 Tetrcycline 10 9.0 13.9 Hemophilus influenze ACM 5188 (HTM f gr, 5% CO 2, 35-37 C) Augmentin 15 7.7 10.1 Neisseri gonorrhoee ACM 5239 (WHO C) (Chocolte Columi Blood Agr, 5% CO 2, 35-36 C, humidity > 80%) Benzylpenicillin 0. 5 u 2.1 4.1 Ceftrixone 0.5 8.2 11.0 Ciprofloxcin 1 12.7 16.3 Nlidixic cid 30 11.3 14.5 Spectinomycin 100 6.9 8.9 Pseudomons eruginos ACM 5189 d (Sensitest, ir, 35-37 C) Amikcin 30 7.4 10.6 Aztreonm 30 8.3 13.1 Cefepime 10 8.1 11.3 Cefpirome 10 8.1 10.6 Ceftzidime 10 7.5 11.9 Ciprofloxcin 2.5 8.9 14.5 Ertpenem g 10 g Gtifloxcin 2.5 7.8 11.4 Gentmicin 10 5.5 9.5 Imipenem 10 7.9 10.3 Meropenem 5 9.7 14.8 Moxifloxcin g 2.5 g Norfloxcin 10 10.1 12.6 Pipercillin 50 8.1 12.9 Polymyxin B 300 u 5.2 7.2 Ticrcillin 75 7.3 12.1 Tormycin 10 7.0 10.6 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. d If ntiiotic discs re tested with Escherichi coli ACM 5185, there is no need to test these ginst Pseudomons eruginos ACM 5189 s well nd vice vers. f Hemophilus Test Medium Bse contining 15 mg/l freshly prepred Hemtin nd NAD. g Ertpenem nd Moxifloxcin should e tested ginst E. coli ACM 5185. Online Edition Septemer 2009 19
Chpter 10. Tles Tle 10.3.c. Reference strins: Aneroic Orgnisms Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Clostridium perfringens ACM 5240 (Supplemented Brucell Medium Bse, neroic, 35-37 C) c Benzylpenicillin 0. 5 u 6.3 7.9 Cefoxitin 10 7.3 9.7 Clindmycin 2 6.1 8.1 Meropenem 5 10.1 12.9 Metronidzole 5 4.3 6.7 Moxifloxcin 2.5 4.7 6.3 Bcteroides frgilis ACM 5196 (Supplemented Brucell medium Bse, neroic, 35-37 C) c Augmentin 3 5.1 8.3 Tzocin 55 9.0 12.2 Timentin 85 11.6 16.0 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. c Brucell Medium Bse contining 5% defirinted horse lood, hemin 5 mg/l nd vitmin K 1 mg/l. Tle 10.3.d. Reference strins: Yest Antiiotics, disc potencies nd cceptle zones of inhiition for reference strins. Antiiotic reported Disc potency (µg) Annulr rdii (mm) Cndid prpsilosis ACM 5283 (Csitone Complex medium, eroic, 30 C) Amphotericin B 10 8.1 9.7 Cspofungin 5 3.9 5.5 Fluconzole 25 12.5 15.7 Itrconzole 10 6.2 7.4 Voriconzole 1 15.7 17.7 Reference strin testing must e performed: (i) In conjunction with the clinicl isolte, or t lest once weekly; (ii) When new tch of medium is used; (iii) When new tch of discs is used. The cceptle rnge (95% confidence limits) is the men ± 2 stndrd devitions. The men ws derived from > 120 mesurements with different opertors using different tches of oth gr nd discs. It is sttisticlly cceptle to use one hundred mesurements to represent the norml distriution nd this gives confidence limit of 95%, mening n in-uilt MU of 5% for the test. Online Edition Septemer 2009 20
Chpter 10. Tles 10.4. Testing nd reporting β-lctm ntiiotics Tle 10.4.. A guide to the testing nd reporting of β-lctm ntiiotics for Grm-negtive orgnisms. Orgnism AMP AMC ATM CAZ CXM,CL,CPD CRO,CTX,KZ Antiiotic,c CPO CTT FEP FOX IPM,MEM ETP PRL TIM TZP Enteroctericee with n inducile AmpC d R R R R R T R R T R R R Aeromons with A2 crpenemse (most A. sori) e R R T T T T T T R e R R R Aeromons with A1 cephlosporinse & A2 crpenemse Providenci sturtii /rettgeri Morgnell. morgnii R R T R R T R R R R R R R R T R R T R R T R R T Proteus vulgris / penneri f R U R T R f R T T T R U U K. oxytoc K1 hyperproducer g R U R T g R g R T T T R U U Enteroctericee with n AmpC R R R R R T R R T R R R Enteroctericee with ESBL R U R R R R T R T R U U Pseudomons species / Burkholderi species h / Chryseocterium species R R h T T R T R R T T T T P. eruginos with ESBL R R R R R R R R T R U U Orgnism with metllo-β-lctmse R R T R R R R R R R R R Stenotrophomons mltophili i R R R i R i R R R R R R i R i R i c d e f g h i Where n orgnism fits into more thn one ctegory resistnce (R) to n ntiiotic in ny one ctegory tkes precedence over the remining ctegories. R = The orgnism is resistnt to the ntiiotic ecuse it possesses mechnism of resistnce tht my not e demonstrted y disc testing. T = Cn e tested. U = Test isoltes from urine only. Isoltes from other sites re considered RESISTANT. AMP mpicillin CL cephlexin CTX cefotxime KZ cefzolin AMC ugmentin CPD cefpodoxime ETP ertpenem MEM meropenem ATM ztreonm CPO cefpirome FEP cefepime PRL pipercillin CAZ ceftzidime CRO ceftrixone FOX cefoxitin TIM Timentin CXM cefuroxime CTT cefotetn IPM imipenem TZP Tzocin Enterocter erogenes, Enterocter cloce, Serrti mrcescens, Citrocter freundii, Hfni lvei. A. cvie does not possess crpenemse (A2) nd cn e tested ginst imipenem, meropenem nd ertpenem. Isoltes with high β-lctmse ctivity my give no zone round CTX 5 µg ut show "key-hole" effect tht my e mistken s n indiction of the presence of n ESBL. However, unlike ESBL producers, they my e susceptile to ceftzidime. K. oxytoc hyperproducer of the K1 enzyme my hve reduced zone of inhiition round cefotxime/ceftrixone disc. However, the orgnism is usully susceptile to ceftzidime nd cn e tested. B. pseudomllei is usully susceptile to Augmentin nd cn e tested ginst this ntiiotic. See Section 5.11 of the CDS mnul for notes on testing S. mltophili ginst these nd other ntiiotics. Online Edition Septemer 2009 21