Download ANTIMICROBIAL RESISTANCE PHENOTYPES IN HOSPITAL

ANTIMICROBIAL RESISTANCE PHENOTYPES IN HOSPITAL ISOLATES
Abbreviation of
resistant phenotype
Resistance mechanism
Detection of resistance
Non-effective
antibiotics
prepared by M. Mnichowska-Polanowska
Active
antibiotics
Genus/species
Location
MSSA
Inactivating enzymes
(betalactamases:
penicillinases)
Disc with OX
better disc with cefoxitin FOX
Classic (natural)
penicillins
Penicillinase-resistant
penicillins (cloxacillin)
Staph.aureus
MRSA
Altered target site
(mec A gene→ PBP 2a
protein)
As above
Beta-lactams
Glycopeptides,
linezolid,
aminoglycosides
Staph aureus
MRCNS
VISA
As above
Altered target
‘Van’ genes
As above
Disc with VA
E-test with VA
Discs with erythromycyn and
clindamycin
As above
Beta-lactams,
vancomycin
Macrolides,
lincosamides
Streptogramins gr B
Aminoglicosydes in
high concentartion
As above
linezolid
CNS
Staph. aureus
other groups
staphylococci,
streptococci
Glycopeptides (mainly
teicoplanin), linezolid
Enterococci
MLSB
Attention
HLAR
Enzymatic modification
of antibiotics
Disc with gentamycin in high
concentration (GN 30)
VRE
Altered targetsite
(Van A-E genes)
Disc with VA
E-test with VA
vancomycin
Linezolid,
tetracyclines,
chloramphenicol
Enterococci
ESBL
Inactivating enzymes
(extended spectrum
betalactamases);
Plasmid -encoded
DDT : cephalosporins III gen.
(CAZ and CTX) and AMC between
them
[CAZ-AMC-CTX]
Pen;
ceph I-IV gen,
monobactams
carbapenems ;
G(-) rods
According to EUCAST recommendations:
Detection of ESBL does not exclude the use of
cef I-IV if was confirmed susceptibility to the
drugs in AST
Inactivating enzymes
derepression of
chromosomal
betalactamase;
Chromosomal and
plasmid-encoded
DDT + FEP: 2 x cephalosporins III
gen, pen/inh between them and
ceph. IV gen (FEP) above pen/inh
FEP
CAZ –AMC - CTX
Pen,
cef I-III gen,
monobactams
G(-) rods
According to EUCAST recommendations:
Detection of ESBL does not exclude the use of
cef I-III if was confirmed susceptibility to the
drugs in AST
discs: 2 x cephalosporins III gen,
pen/inh between them and ceph. IV
gen above pen/inh
carbapenems
G(-) rods
No drug of proven
efficacy and safety; due
to AST
Most often in:
Klebsiella,
Enterobacter,
Aztreonam; no drug of
proven efficacy and
safety; due to AST
Mostly
Pseudomonas
AmpC
ESBL + AmpC
risk of selection of
ESBLstrains - pen/inh,
ceph I-IV gen,
monobactamsCarbapenems,
Ceph IV gen
risk of selection of
ESBLstrains - cef I-III
KPC
Inactivating enzymes
Plasmid-encoded
Hodge test – coverleaf test, result:
coverleaf –like identation
CDT [MEM/ MEM + boronic acid]
Pen,
pen/inh
cef I-IV gen,
monobactams
beta-lactams
(including all the
carbapenems)
MBL
Inactivating enzymes
MBL genes encoded in
mobile gene elements.
DDST [CAZ + EDTA+ IPM]
CDT [IPM/ IPM + EDTA ]
most beta- lactam
carbapenems
Natural resistance to cephalosporins and
aminoglycosides in low concentation , inability
of use of synergystic therapy : b-lactam
/glycopeptide + aminoglycoside
The mortality due to infections caused by KPC
may reach 50%; increased potential to cause
outbreaks; GIT – may be reservoir of KPC
strains
List of abbreviations used in the table.
AMC
AST
CAZ
CDT
Cef
CNS
CTX
DDT
DDST
ESBL
EUCAST
FEP
FOX
GIT
HLAR
IPM
KPC
MBL
MEM
MSSA
MRSA
OX
VA
VISA
VRE
amoxicillin/clavulanic acid
antimicrobial susceptibility testing
ceftazidime
combined disk test
cephalosporins
coagulase – negative staphylococci
cefotaxime
double disk test
double disk synergy test
extended spectrum beta-lactamase
European Comittee on Antimicrobial Susceptibility Testing
cefepime
cefoxitin
gastrointestinal tract
high level aminoglicoside resistant
imipenem
Klebsiella pneumoniae carbapenemase
metallo- beta lactamase
meropenem
meticillin susceptible S. aureus
meticillin resistant S. ureus
oxacillin
vancomycin
vancomycin intermidiate S. aureus
vancomycin resistant enterococci