Beta-lactam antibiotics - MIC-breakpoints (version 2009-04-28)

All breakpoints in this table harmonised through EUCAST (except ongoing process for oral cephalosporins; lines marked in yellow).
Words and breakpoints in hypertext (link): always consult footnote prior to use.

Previous version of MIC-breakpoints.
 

Link from antibiotic to EUCAST MIC-distributions

Breakpoints
not related
to species

 Enterobact-
eriaceae		 Pseudo-
monas		 Acineto-
bacter		 Staphylo-
coccus		 Entero-
coccus		 Streptococcus
A,B,C,G		 S.pneu-
moniae		 Other
strepto
cocci		 H.influenzae M.catarrhalis P.multo-cida
Method: - A A A A B B B B B B B
Penicillin G 0.25/2 - - - 0.12/0.12 Note 0.25/0.25*
 		 0.06/2
 Meningitis: 0.06/0.06		 0.25/2 IE - IE
Penicillin V IE - - - Note - Note* Note Note - - 0.5/0.5
Oxacillin+
 (Cloxa-, dicloxa- & flucloxacilin)		 IE - - - Note - - - - - - -
Cefoxitin - - - - 4/4 - - - - - - -
Ampicillin
(Amoxicillin)		 2/8 1/8 - - Note 4/8 Note* 0.5/2 0.5/2 1/1 Note 0.5/0.5
Amoxicillin-clavulanate 2/8 1/8 - - Note Note Note* Note Note 1/1 1/1 Note
Pivmecillinam(U) IE 8/8 - - Note - - - - - - -
Piperacillin-
tazobactam		 4/16 8/16 16/16 IE Note Note Note* Note Note Note Note IE
Imipenem 2/8 2/8* 4/8 2/8 Note E.faecalis:4/8
 E.faecium:-		 2/2* 2/2*
Meningitis:-		 2/2 2/2
Meningitis:-		 2/2 IE
Meropenem 2/8 2/8 2/8 2/8 Note - 2/2* 2/2*
Meningitis:0.25/1		 2/2 2/2
Meningitis:0.25/1		 2/2 IE
Ertapenem 0.5/1 0.5/1 - - Note - 0.5/0.5* 0.5/0.5
Meningitis:-		 0.5/0.5 0.5/0.5
Meningitis:-		 0.5/0.5 IE
Doripenem 1/4 1/4 1/4 1/4 Note - 1/1* 1/1
Meningitis:-		 1/1 1/1
Meningitis: -		 1/1  
Aztreonam 4/8 1/8 1/16 - - - - - - IE IE IE
 Link from antibiotic to EUCAST MIC-distributions

Breakpoints
not related
to species

 Enterobact-
eriaceae		 Pseudo-
monas		 Acineto-
bacter		 Staphylo-
coccus		 Entero-
coccus		 Streptococcus
A,B,C,G		 S.pneu-
moniae		 Other
strepto
cocci		 H.influenzae M.catarrhalis P.multo-cida
Cefalexin 1/8 1/8 - - Note - 1/1 1/1 - - - -
Cefalexin IE 16/16 (U) - - Note - Note* - - - - -
Cefadroxil 1/8 1/8 - - Note - 1/1 1/1 - - IE -
Cefadroxil IE 1/16 (U) - - Note - Note* - - - - -
Cefpodoxime 1/2 1/2 - - - - 0.06/1 0.06/0.12 - 0.25/0.5 1/2 IE
Cefpodoxime IE 1/1 (U) - - Note - Note* 0.25/0.5 - 0.25/0.5 0.25/0.5 IE
Loracarbef 2/4 2/2 (U) - - Note - 1/1* 1/1 - 2/4 2/4 -
Ceftibuten 1/4 1/4 - - - - 1/4* - - 0.25/0.5 1/4 IE
Ceftibuten IE 1/1 (U) - - IE - Note* IE - 1/1 1/1 IE
Cefuroxime-axetil 2/2 - - - Note - 0.12/2 0.12/0.25 - 2/2 2/2 -
Cefuroxime-axetil IE 8/8 (U) - - Note - Note* 025/0.5 - 0.12/1 0.12/2 -
Cefuroxime 4/8 8/8 - - Note - 0.5/0.5* 0.5/1 Pending 1/2 1/2 IE
Cefotaxime
Ceftriaxone		 1/2 1/2 - - Note - 0.5/0.5* 0.5/2 Pending 0.12/0.12 0.12/0.12 0.12/1
Ceftazidime 4/8 1/8 8/8 - - - - - - - - IE
Cefepime 4/8 1/8 8/8 - Note - 0.5/0.5* 1/2 Pending 0.25/0.25 0.25/0.25 IE

Oral cephalosporins (yellow markings) - harmonisation by EUCAST 2009.

 

*Isolat med MIC-värden över S/I-brytpunkten är ovanliga eller har ännu inte beskrivits. Identifiering och resistensbestämning skall upprepas och om resultatet konfirmeras skickas isolatet till referenslaboratorium.

(U) Brytpunkterna gäller endast vid nedre okomplicerad urinvägsinfektion.

*Isolates with MIC values above the S/I-breakpoint are very rare or not yet reported. The identification and antimicrobial susceptibility tests on any such isolate must be repeated and if the result is confirmed the isolate sent to a reference laboratory..

(U) = Breakpoints valid for uncomplicated urinary tract infections only.

Note/brytpunkt i hypertext - länk till särskild information om brytpunkten. Informationen finns i samma dokument som den länk som ges från artnamnen. För den som skriver ut tabellen på papper är det viktigt att även alla fotnoter skrivs ut och följer med tabellen.

 Note/breakpoint in hypertext = a link to a footnote. If you print the table on paper, remember to print the footnotes - they contain important information on methodology.
4/8 - sättet att beskriva MIC-gränser (exempelvis 4/8) skall tolkas S< 4 och R>8 mg/L.

IE - Klinisk effekt utesluts ej men in vitro och/eller in vivo dokumentation saknas.

-  RAF avråder från resistensbestämning. Ej relevant behandlingsalternativ: 

  1. godkänd indikation saknas
  2. otillräcklig aktivitet även mot bakterier som ej utvecklat resistens
  3. resistens så vanlig (>50%) att medlet får anses oanvändbart
4/8 - breakpoints for SIR-categorisation: S< 4 mg/l and  R>8 mg/L.

IE - Clinical effect is not ruled out but EUCAST/SRGA have not been able to find enough clinical evidence to determine a breakpoint.

-  SRGA advices against susceptibility testing. Not a relevant alternative:

  1. no approved indication
  2. insufficient activity
  3. extensive resistance development - the drug may be considered obsolete.
Metod:
A = grundmedium utan tillsatser. Inkubation 35o C i luft.
B = grundmedium + 5% skakhästblod.+ NAD. Inkubation i 5 % CO2 vid 35o C .

Method:
A = medium without additives. Incubation in air, 35o C.
B = medium + 5% defibrinated horse blood + NAD. Incubation in 5 % CO2 at 35o C.

 

RAF & RAF-M
Uppdaterat 2009-05-03, G Kahlmeter