Infectious Diseases II
Assay
Technology
Manufacturer/
Trade Name
Organisms/Antimicrobial
Resistance Targets
Detection Time
After Positive Growth
on Blood Culture
Chromogenic
media
| โข | CHROMagar |
|---|
S. aureus, MRSA, Enterococcus spp.,VRE,
S. agalactiae, E. coli (Shiga toxin, EC-O157),
Klebsiella spp., Proteus spp., Pseudomonas
spp., Acinetobacter spp., Yersinia spp.; KPC
(carbapenem), CTX-M (ESBL)
C. albicans, C. tropicalis, C. krusei
24โ48 hr
ESBL = extended-spectrum ฮฒ-lactamase; KPC = Klebsiella pneumoniae carbapenemase; MALDI-TOF = matrix-assisted laser desorption-ionization/time of flight;
MRSA = methicillin-resistant S. aureus; NDM = New Delhi metallo-ฮฒ-lactamase; PCR = polymerase chain reaction; PNA FISH = peptide nucleic acid fluorescence in
situ hybridization; VRE = vancomycin-resistant enterococci.
Reproduced with permission from: Goff DA, Jankowski C, Tenover F. Using rapid diagnostic tests to optimize antimicrobial selection in antimicrobial stewardship
Genes from Rapid Diagnostic Tests for Positive Blood Culturesa
Resistance Genes
Species
Recommended Therapy
Alternative Therapy
mecA-negative
S. aureus
Oxacillin
Nafcillin
Cefazolin
Vancomycin (if intolerance to
ฮฒ-lactams)
mecA-positive
S. aureus
Vancomycin
Daptomycin
Linezolid
Ceftaroline
vanA/B-negative
E. faecalis
Ampicillin
Vancomycin (if allergic to ฮฒ-lactams)
vanA/B-positive
E. faecalis
Daptomycin
Linezolid
vanA/B-negative
E. faecium
Vancomycin
Daptomycin (if intolerance to
vancomycin)
vanA/B-positive
E. faecium
Daptomycin
Linezolid
CTX-M (ESBL)a
Enteric gram-negative
pathogens
Carbapenems (ertapenem,
imipenem, meropenem)
Ceftazidime/avibactam
Meropenem-vaborbactam
Imipenem-cilastatin-relebactam
Cefiderocol
KPCa
K. pneumoniae
and other enteric
gram-negative
pathogens
Ceftazidime/avibactam
Meropenem/vaborbactam
Imipenem/cilastatin/
relebactam
Colistin/polymyxin B
Tigecycline/eravacycline
Cefiderocol
NDM
carbapenemasea
K. pneumoniae
and other enteric
gram-negative
pathogens
Cefiderocol
Aztreonam + ceftazidime/
avibactam
Colistin/polymyxin B
Tigecycline
VIM or IMP
carbapenemasea
P. aeruginosa
Colistin/polymyxin B
Aztreonam
Cefiderocol