SHC Antibiogram: Streptococci & Enterococci 2008

• SHC Antibiogram 2008   (printable PDF)

Percent Susceptible by Broth Microdilution, Etest, or Disk Diffusion

	No. Test- ed (a)	Penicillin or Ampicillin			Cef- uro- xime	Cef- tria- xone	Vanco- mycin	Erythro- mycin	Clinda- mycin	Mero- penem	Tri- metho- prim/ sulfa	Tetra- cycline (Doxy- cyc- line)	Genta- micin Syn- ergy with Pen/ Amp	Strepto- mycin Syn- ergy with Pen/ Amp	Moxi- flox- acin	Nitro- furan- toin (UTI only)	Quino- pristin/ dalfo- pristin	Cipro- flox- acin	Line- zolid
		%S	%I	%R
Streptococci
Grp. B (Strep. agalactiae) (b)	294	100%	0%	0%	-	100%	-	59%	61%	-	-	-	-	-	-	-	-	-	-
Viridans (various species) (c)	147	84%	15%	1%	-	95%	100%	63%	80%	-	-	-	-	-	-	-	-	-	-
Strep. pneumoniae (d)	62	81% e	-	19%	89%	90%	100%	77%	85%	90%	75%	-	-	-	100%	-	-	-	-
Enterococci
Enterococcus (no species I.D.) (f)	495	84%	0%	16%	-	-	88%	-	-	-	-	27%	-	-	-	86%	-	66%	100%
Enterococcus faecalis (f)	106	100%	0%	0%	-	-	100%	-	-	-	-	-	62%	60%	-	100%	-	75%	100%
Enterococcus faecium (f)	114	12%	0%	88%	-	-	32%	-	-	-	-	50%	94%	50%	-	40%	88%	20%	98%
Cost ($)		$	$	$	$	$$	$	$	$$	$$	$	$	$	$	$$	$	$$$	$$	$$$

(a) Not all isolates tested against every antibiotic listed.

(b) Penicillin is the drug of choice for all beta hemolytic streptococci; penicillin resistance has not been documented.

(c) Clinically important species tested; MICs for penicillin and ceftriaxone performed on 146 strains.

(d) Penicillin-susceptible isolates are also susceptible to all other β-lactam agents. β-lactamase inhibitor combination drugs do not add additional efficacy to penicillin alone.

(e) Based on meningitis interpretive criteria (more conservative). Nonmeningitis interpretation is 100%. Infectious diseases consultation is recommended for meningitis in penicillin-allergic patients or those with resistant ceftriaxone or cefotaxime results.

(f) If susceptible, ampicillin is the drug of choice when enterococci must be treated. Ampicillin susceptibility predicts piperacillin susceptibility. Nitrofurantoin or ampicillin is recommended for uncomplicated UTI. Serious infections (septicemia, endocarditis) require both a β-lactam agent and an aminoglycoside. Use vancomycin+aminoglycoside only if strain is ampicillin-resistant or patient is penicillin - allergic. High level resistance to gentamicin also indicates lack of synergy for tobramycin, amikacin and kanamycin.