La ricerca sugli antibiotici: a che punto siamo?
Quali suggerimenti vengono dalla
moderna ricerca in Microbiologia?
Giovanni Gesu
S.C. Microbiologia e Virologia
Ospedale Niguarda Ca’ Granda
Milano, 14 novembre 2011
Multidrug-resistant bacterial pathogens
are on the rise
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Fischbach MA, Walsh CT Science 28 August 2009; 325:1089-1093
Antibiotic resistance is ancient
A collection of genes encoding
resistance to ß-lactam, tetracycline
and glycopeptide antibiotics found in
DNA from 30,000-year-old Beringian
permafrost sediments.
Antibiotic resistance is a natural phenomenon
that predates the modern selective pressure of
clinical antibiotic use.
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D’Costa VM et al Nature 22 September 2011 477:457–461
Spectra and target locations of antibacterials
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Silver LL Clinical Microbiology Reviews January 2011; 24:71–109
Systemic monotherapeutic antibacterials
and their targets
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Silver LL Clinical Microbiology Reviews January 2011; 24:71–109
Mechanisms of antibacterial resistance
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Silver LL Clinical Microbiology Reviews January 2011; 24:71–109
History of antibiotic discovery and concomitant
development of antibiotic resistance
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Davies J, Davies D Microbiology and Molecular Biology Reviews, September 2010; 74:417–433
Streptococcus pneumoniae
Enterococcus
faecium
ß-Lactams
Low affinity Pbps
Macrolides
Constitutive erm expression
Fluoroquinolone
Mutant topoisomerases
Ampicillin
Low affinity Pbp
Vancomycin
Altered peptidoglycan precursor
Linezolid
Mutant ribosomal RNA genes
Daptomycin
Mechanism unclear
No single drug shows bactericidal
effect against enterococci
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GP Gesu
Microbiology and Molecular Biology Reviews, September 2010; 74:417
Colonizzazione Gastro-Enterica e
diffusione di VRE
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Donskey et al Clin Microbiol Newsletter 1999; 8:57-65
Ruolo della Pressione di Colonizzazione nella
Diffusione dei VRE
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Bonten M et al Arch Intern Med 1998; 158:1127-1132
Antibiogramma per Enterococchi
Infezioni sistemiche
•
Ampicillina
–
•
Vancomicina
–
•
•
•
•
Piperacillina
In associazione
•
Gentamicina
•
Streptomicina
Teicoplanina
Daptomicina
Linezolid
Quinupristin/Dalfopristin
Tigeciclina
Infezioni urinarie
•
•
•
•
Nitrofurantoina
Tetraciclina
Amoxicillina
Norfloxacina
–
Levofloxacina
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Enterococchi Vancomicina-dipendenti...
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the “discovery void”
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Silver LL Clinical Microbiology Reviews January 2011; 24:71–109
Staphylococcus aureus: invasive isolates
resistant to oxacillin (MRSA), 2009
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Streptococcus pneumoniae
Enterococcus faecium
Staphylococcus
aureus
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b-Lactam
Low affinity Pbps
Fluoroquinolone
Mutant topoisomerases
Ampicillin
Low affinity Pbp
Vancomycin
Altered peptidoglycan
precursor
Linezolid
Mutant ribosomal RNA genes
Daptomycin
Mechanism unclear
Penicillin
beta-Lactamase
Oxacillin
Low affinity Pbps
Clindamycin
Constitutive erm expression
Vancomycin
Altered peptidoglycan
precursor
Class Modifications
•
Improvements of the parent compound adding
–
–
–
–
•
•
•
•
•
bacterial spectrum
safety
simpler dosing regimens
activity insusceptible to specific resistance mechanisms
Oritavancin
Iclaprim
Ceftobiprole
Telavancin
Ceftaroline
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Between 1962 and 2000, no major classes of
antibiotics were introduced...
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GP Gesu
Fischbach MA, Walsh CT Science 28 August 2009; 325:1089-1093
Peleg AY and Hooper DC New England Journal of Medicine 2010; 362:1804-1813
Enterobacteriaceae: resistenza intrinseca
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Expert rules at www.eucast.org
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Bush K, Jacoby GA Antimicrobial Agents and Chemotherapy March 2010; 969-976
Synthetic tailoring to create successive
generations of antibiotic classes
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Fischbach MA, Walsh CT Science 28 August 2009; 325:1089-1093
Klebsiella
pneumoniae
Cephalosporins
ESBLs (variety)
Carbapenems
KPC-type beta-lactamases
NDM-1 beta-lactamases
Fluoroquinolone
s
Mutant topoisomerases
Qnr enzymes
Modifying enzyme (Ciprofloxacin)
Efflux pumps (intrinsic and
acquired)
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Klebsiella pneumoniae: invasive isolates resistant to
third-generation cephalosporins, 2009
Italia: 37.1%
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Worldwide distribution of different classes of
CTX-M β-lactamases
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Klebsiella
pneumoniae
Hawkey PM and Jones AM Journal of Antimicrobial Chemotherapy 2009 64(Suppl. 1):i3-i10
Cephalosporins
ESBLs (variety)
Carbapenems
KPC-type beta-lactamases
NDM-1 beta-lactamases
Fluoroquinolone
s
Mutant topoisomerases
Qnr enzymes
Modifying enzyme (Ciprofloxacin)
Escherichia
coli
Cephalosporins
Efflux pumps (intrinsic and
CTX-M
beta-lactamases
acquired)
Carbapenems
KPC-type beta-lactamases
NDM-1 beta-lactamases
Fluoroquinolones Mutant topoisomerases
Qnr enzymes
Modifying enzyme (Ciprofloxacin)
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Efflux pumps (intrinsic and acquired)
Escherichia coli: invasive isolates resistant to
third-generation cephalosporins, 2009
Italia: 17%
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Incremento di E. coli produttore di ESBL (CTX-M) in Italia
100%
6.3%
7.4%
80%
Prevalenza (%) per specie
Altre specie
P. stuartii
Enterobacter
E. coli
P. mirabilis
K. pneumoniae
60%
40%
20%
0%
1999
Spanu T et al Antimicrobial Agents Chemotherapy 2002; 46:196
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2003
Produttori di CTX-M
Luzzaro F et al Journal of Clinical Microbiology 2006; 44:1659
Studio OASIS (Batteriemie)
Diffusione di ESBL in Enterobatteri (n = 965)
Totale
%
ESBL
Area
medica
(n = 618)
%
ESBL
Area
chirurgica
(n = 162)
%
ESBL
Area
critica
(n = 135)
%
ESBL
E. coli
555
(57.5%)
15.1
384
(62.1%)
15.1
83
(51.2%)
9.6
55
(40.7%)
20.0
K. pneumoniae
258
(26.7%)
26.7
139
(22.5%)
22.3
60
(37.0%)
30.0
52
(38.5%)
38.5
P.mirabilis
152
(15.8%)
32.2
95
(15.4%)
37.9
19
(11.7.%)
15.8
28
(20.7%)
25.0
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Studio OASIS
Resistenze associate in Escherichia coli
E. coli
FQ-R
ESBL+
AK-R
%FQ-R in %FQ-R in
ESBL+
ESBL-
%AK-R
in
ESBL-
%AK-R
in ESBL+
Totale
537
36.9%
15.1%
5.8%
28.5%
84.0%
2.4%
24.7%
Ospedale
278
47.1%
21.9%
7.6%
36.4%
85.2%
1.8%
27.9%
Extraospedale
259
25.9%
7.7%
3.9%
21.3%
80.0%
2.9%
15.0%
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Microbiology and Molecular Biology Reviews, September 2010; 74:417
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Klebsiella pneumoniae produttore di SHV-18 (ATCC 700603)
Diffusione in agar di Mueller-Hinton:
test di sinergia con acido clavulanico (distanza centro-centro 25 mm)
Aztreonam
Cefotaxime
Ceftazidime
Ceftriaxone
Diametro aloni:
ceftazidime, 18 mm; cefotaxime, 24 mm; ceftriaxone, 22 mm; aztreonam, 16 mm
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Studio OASIS - Batteriemie
Klebsiella pneumoniae (N = 258)
Klebsiella pneumoniae ESBL+
C-20
C-19
C-18
C-17
C-16
C-15
C-14
C-13
C-12
C-11
C-10
C-09
C-08
C-07
C-06
C-05
C-04
C-03
C-02
C-01
62.5
4 Ertapenem R
18.8
45.5
20.0
0.0
23.1
33.3
58.8
0.0
2 Ertapenem R
8.3
68.8
0.0
5 Ertapenem R
33.3
42.9
28.6
17.6
14.3
Media 28.9%
8.3
14.3
28.6
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
EARSS = 34.9%
Resistenza emergente ai carbapenemi nelle
Enterobacteriaceae
ESBL o
produzione di AmpC
+
perdita di porine
Produzione di MBL
(VIM, IMP)
Produzione di
carbapenemasi a serina
(KPC, SME, IMI)
89 Klebsiella spp.
59 Enterobacter spp.
(isolati non sensibili
ai carbapenemi)
Klebsiella pneumoniae
resistente ai carbapenemi (EARSS 2007)
Woodford et al., J Antimicrob Chemother 2007; 50:582
Surmounting resistance with scaffold
alterations
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Fischbach MA, Walsh CT Science 28 August 2009; 325:1089-1093
Chemical structures of new and underexplored
categories of antibiotics
Fischbach MA, Walsh CT Science 28 August 2009; 325:1089-1093
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Pseudomonas aeruginosa: evoluzione verso la
resistenza agli antibiotici beta-lattamici
Meccanismo
Perdita OprD (mutazione)
Efflusso (mutazione)
- MexAB-OprM
- MexCD-OprJ
- MexXY-OprM
Derepressione
di AmpC (mutazione)
PEN
CAZ
FEP
ATM
-
-
-
-
+/-
+/-
IMI
MEM
+
+/-
+/-
+/-
-
+/-
-
-
+/-
-
+/-
+
-/+
+
+
+
+
+
-
-
+
+
+
-
+
+
-
+/-
-
-
Acquisizione di betalattamasi
(trasferimento genico)
- ESBL a serina
(PER-1, GES, OXA-18)
- Metallo-beta-lattamasi
(IMP, VIM)
Metallo-ß-lattamasi: principali varianti in Italia
VARESE
VIM-1 P. putida
VIM-2 P. aeruginosa
VIM-4 E. cloacae
K. pneumoniae
IMP-2 P. aeruginosa
IMP-12 P. putida
IMP-13 P. aeruginosa
MILANO
VIM-1 P. aeruginosa
VERONA
VIM-1 P. aeruginosa
A. xylosoxidans
VIM-2 P. aeruginosa
IMP-2 A. baumannii
TRIESTE
VIM-1 P. aeruginosa
VIM-2 P. aeruginosa
SIENA
VIM-1 P. aeruginosa
PAVIA
VIM-1 P. aeruginosa
VIM-2 P. aeruginosa
ATRI
IMP-13 P. aeruginosa
GENOVA
VIM-1 P. aeruginosa
S. GIOVANNI ROTONDO
IMP-13 P. aeruginosa
PISA
VIM-4 P. aeruginosa
ROMA
VIM-1 P. aeruginosa
VIM-2 P. aeruginosa
IMP-2 A. baumannii
IMP-13 P. aeruginosa
PALERMO
VIM-1 P. aeruginosa
CATANIA
VIM-1 P. aeruginosa
P. aeruginosa produttore di VIM-1 MBL
Resistenza ad alto livello verso cefalosporine di ultima
generazione e carbapenemici
Sensibilità verso aztreonam
ATM
Enterobatteri produttori di ESBL e MBL
Klebsiella pneumoniae from ICU patients
Sensibilità
agliAmikacina
antibiotici R
Carboxy-pen.
R
Ureido-pen. R
Gentamicina
BLICs
R
Tobramicina
Cefepime R
Netilmicina
Ceftazidime R
SXT
R
Cefotaxime R
Tetracicline
Aztreonam
R
Imipenem R
Meropenem R
R
R
R
R
Produzione di ESBL SHV-5 e MBL VIM-1
Miriagou V et al Journal of Antimicrobial Chemotherapy 2005; 55:810
% carbapenem-resistant
Emergence of carbapenem resistance
in K. pneumoniae: USA East Coast
50
45
40
35
30
25
20
15
10
5
0
Due to spread of KPC
carbapenemases
22% of isolates resistant to:
Aminoglycosides
Fluoroquonolones
3rd 4th gener. Cephems
Carbapenems
XDR phenotype
1999
2001
Years
2006
Also in E. coli, C. freundii, and
E. cloacae from the same area
Jones et al – DMID 2008
Landman et al - JAC 2007
Geographic distribution of KPC worldwide
Nordmann P et al The Lancet Infectious Diseases 2009; 9:228–236
Carbapenemasi di tipo KPC
Italia 2010
Courtesy of GM Rossolini
Antibiogramma di K. pneumoniae KPC-Positiva
Antibiotico
Interpretazione
Antibiotico
Interpretazione
Amikacina
I/R
Cloramfenicolo
R
Amoxi/clav
R
Ciprofloxacina
R
Ampicillina
R
Ertapenem
R
Aztreonam
R
Imipenem
R
Cefazolina
R
Meropenem
R
Cefpodoxime
R
Pipera/Tazo
R
Cefotaxime
R
Gentamicina
S/I/R
Cetotetan
R
Tobramicina
R
Cefoxitin
R
Trimeth/Sulfa
R
Ceftazidime
R
Polimixina B
MIC >4 mg/L
Ceftriaxone
R
Colistina
MIC >4 mg/L
Cefepime
R
Tigeciclina
2 (?)
Enterobacteriaceae: resistenza intrinseca
Expert rules at www.eucast.org
Microbiological detection of KPC-2 Carbapenemases
Ertapenem
Imipenem
clavulanic acid
Nordmann P et al The Lancet Infectious Diseases 2009; 9:228–236
Test di Hodge = positivo
Test con ac. boronico: positivo
Klebsiella pneumoniae produttore di NDM-1
New Dehli Metallo-beta-Lactamase-1
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NDM-1 K. pneumoniae
The Origin and Spread of NDM-1.
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Moellering RC Jr. New England Journal of Medicine December 16, 2010; 363:2377-2379
Distribution of NDM-1-producing
Enterobacteriaceae
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Kumarasami KK et al Lancet Infectious Diseases, September 2010; 10:597-602
Numbers of carbapenemase-producing
Enterobacteriaceae referred from UK
laboratories
KPC
OXA-48
IMP
VIM
NDM-1
GP Gesu
Kumarasami KK et al Lancet Infectious Diseases, September 2010; 10:597-602
Worldwide distribution of identified cases of bacteria with
NDM-1 enzyme as of 1 October 2011
traced back to the Indian subcontinent
traced to the Balkan states and the Middle East
unknown source of infection or colonization
Nordmann P et al Trends in Microbiology 2011 1–8
Map of NDM-1-positive samples from New Delhi
centre and surrounding areas
Walsh TR et al Lancet Infectious Diseases May 2011; 11: 355–362
Worldwide dissemination of different types of
metallo-β-lactamases
Cornaglia G et al Lancet Infectious Diseases May 2011; 11: 381–393
Key chronological events
of the NDM-1 story
Walsh TR, Toleman MA Journal of Antimicrobial Chemotherapy Advance Access published October 12, 2011
Pseudomonas
aeruginosa
Carbapenems
Metallo-beta-lactamases
AmpC/porin reduction combinations
Aminoglycosides
Modifying enzymes
Fluoroquinolones Mutant topoisomerases
Efflux pumps (intrinsic and acquired)
Acinetobacter baumanni
Carbapenems
OXA-type beta-lactamases
Amikacin
Ribosomal methylase
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Acinetobacter baumannii: resistenza acquisita
ai carbapenemi per produzione di carbapenemasi
Ceppo sensibile
Carbapenemasi
Classe D acquisita
(OXA-23 OXA-40 OXA-58)
Bertini A et al Antimicrobial Agents Chemotherapy January 2006; 2268
Ceppo resistente
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MBL acquisita
(IMP - VIM - SIM)
Cornaglia G et al The Lancet 1999; 353:899
Acinetobacter baumannii: cloni multiresistenti
A. baumannii clone B produttore di OXA-58 in 9 ospedali italiani
(sorveglianza 2004, 14 laboratori, 12 centri)
Sensibilità agli antibiotici
Ampi/Sulb I
Pipera/Tazo
Cefepime R
Ceftazidime
Cefotaxime
Imipenem R
Meropenem
R
R
R
Amikacin I
Gentamicin R
Tetracycline R
Ciprofloxacin R
Colistin
S
2004-2005
•
OXA-58
•
OXA-23
in 9 regioni
R
Pagani et al. 46th ICAAC
GP Gesu
Mezzatesta ML et al Poster O440 19th ECCMID
Acinetobacter baumannii
Geographical distribution of the different MLST
types
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Gogou V et al Journal of Antimicrobial Chemotherapy 2011;jac.dkr390
Antibiotic resistance is ancient
New antibiotics will select for preexisting resistance determinants that
have been circulating within the
microbial pangenome for millennia.
This reality must be a guiding principle in
our stewardship of existing and new
antibiotics.
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GP Gesu
D’Costa VM et al Nature 22 September 2011 477:457–461