Aura 2016: first Australian report on antimicrobial use and resistance in human health
Yüklə 1,59 Mb.
|
- Bu səhifədəki naviqasiya:
- Types and impact of resistance
- Key findings (national)
- Jurisdictional rates
- Additional findings from targeted surveillance
Treatmentβ-lactam agents, including those combined with β-lactamase inhibitors, are preferred for treatment of infections caused by these species. The aminoglycosides (especially gentamicin) are also recommended, usually for empirical use, pending the results of culture and susceptibility testing. In Australia, fluoroquinolones are recommended only for strains that are resistant to other classes of antimicrobials. Trimethoprim and cotrimoxazole (trimethoprim–sulfamethoxazole) are recommended for treatment of lower urinary tract infection. Types and impact of resistanceThe most common resistance mechanisms in Enterobacteriaceae are β-lactamases. The acquired TEM 1 β-lactamase has become so common worldwide that it is found in at least half of the strains isolated from humans in Australia, making them resistant to ampicillin and amoxicillin. Both K. pneumoniae and E. cloacae complex contain intrinsic β-lactamases that make them naturally resistant to ampicillin/amoxicillin. In addition, the intrinsic β-lactamase of E. cloacae complex makes this species resistant to first-generation cephalosporins such as cefazolin and cephalexin, and the enzyme can be easily upregulated to make the species resistant to third-generation cephalosporins such as ceftriaxone, cefotaxime and ceftazidime. The β-lactam/β-lactamase inhibitor combinations amoxicillin–clavulanate and piperacillin–tazobactam are the usual treatments for TEM 1–producing E. coli, K. pneumoniae and E. cloacae complex, along with third-generation cephalosporins. The acquired β-lactamases of greatest interest are the extended-spectrum β-lactamases (ESBLs), the plasmid-borne AmpC enzymes (pAmpCs) and the carbapenemases. ESBLs and pAmpCs render Enterobacteriaceae resistant to third-generation cephalosporins, and carbapenemases confer resistance to carbapenems and almost all other β-lactams. Carbapenemase-producing Enterobacteriaceae (CPE) are almost always highly multidrug resistant. Meropenem is the most widely used option for infections caused by strains that produce ESBLs and pAmpCs; the suitability of piperacillin–tazobactam as a ‘carbapenem sparing’ agent for strains with ESBLs is under investigation. Infections caused by CPE require ‘last line’ reserve agents such as colistin, an agent with significant toxicity. Other resistance mechanisms in Enterobacteriaceae that have clinical impact include the aminoglycoside-modifying enzymes, which render strains resistant to gentamicin and tobramycin (but susceptible to amikacin), and the ribosomal methylases, which confer resistance to gentamicin, tobramycin and amikacin. Resistance to fluoroquinolones is usually through mutations at the target sites (the topoisomerases), but, recently, plasmid-borne resistance has emerged. Resistance to trimethoprim and sulfamethoxazole is common and occurs through a variety of mechanisms.
Rates of resistance were lower in the community for most agents where data was available, compared with hospitals and residential aged care facilities (Figures 4.4, 4.6 and 4.8). Figure 4.3 Escherichia coli resistance, by specimen source, 2014 
AMC = amoxicillin–clavulanate; AMP = ampicillin; CIP= ciprofloxacin; CTR = ceftriaxone; CZL = cefazolin; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: OrgTRx (Queensland); Australian Group on Antimicrobial Resistance (national); Sullivan Nicolaides Pathology (Queensland and northern New South Wales)
Figure 4.4 Escherichia coli resistance, by clinical setting, 2014 
AMC = amoxicillin–clavulanate; AMP = ampicillin; CIP= ciprofloxacin; CTR = ceftriaxone; CZL = cefazolin; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: Australian Group on Antimicrobial Resistance (AGAR) (public hospitals); OrgTRx (public hospitals and health services); AGAR and Sullivan Nicolaides Pathology (SNP) (private hospitals); SNP (community and residential aged care facilities) Data table: Figure 4.4
Figure 4.5 Klebsiella pneumoniae resistance, by specimen source, 2014 
AMC = amoxicillin–clavulanate; CIP= ciprofloxacin; CTR = ceftriaxone; CZL = cefazolin; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: OrgTRx (Queensland); Australian Group on Antimicrobial Resistance (national); Sullivan Nicolaides Pathology (Queensland and northern New South Wales)
Figure 4.6 Klebsiella pneumoniae resistance, by clinical setting, 2014 
AMC = amoxicillin–clavulanate; CIP= ciprofloxacin; CTR = ceftriaxone; CZL = cefazolin; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: Australian Group on Antimicrobial Resistance (AGAR) (public hospitals); OrgTRx (public hospitals and health services); AGAR and Sullivan Nicolaides Pathology (SNP) (private hospitals); SNP (community and residential aged care facilities) Data table: Figure 4.6
Figure 4.7 Enterobacter cloacae complex resistance, by specimen source, 2014 
CIP = ciprofloxacin; CTR = ceftriaxone; CPM = cefepime; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: OrgTRx (Queensland); Australian Group on Antimicrobial Resistance (national); Sullivan Nicolaides Pathology (Queensland and northern New South Wales)
Figure 4.8 Enterobacter cloacae complex resistance, by clinical setting, 2014 
CIP = ciprofloxacin; CTR = ceftriaxone; GEN = gentamicin; MER = meropenem; na = not available (either not tested or tested against an inadequate number of isolates); NOR = norfloxacin; PTZ = piperacillin–tazobactam; SXT = trimethoprim–sulfamethoxazole; TMP = trimethoprim Sources: Australian Group on Antimicrobial Resistance (AGAR) (public hospitals); OrgTRx (public hospitals and health services); AGAR and Sullivan Nicolaides Pathology (SNP) (private hospitals); SNP (community and residential aged care facilities) Data table: Figure 4.8
Jurisdictional ratesData on resistance rates across the jurisdictions is available to AURA through the AGAR program, from blood culture isolates. Tables 4.4–4.6 show the resistance rates to all drugs tested. There were some notable differences between jurisdictions in the prevalence of some important resistances. For E. coli, resistance to ceftriaxone ranged from 6.2% in South Australia to 12.9% in Victoria; resistance to gentamicin ranged from 5.1% in Tasmania to 9.1% in Victoria; and resistance to ciprofloxacin ranged from 6.3% in Tasmania to 14.0% in Victoria. For K. pneumoniae, resistance to ceftriaxone ranged from 4.1% in South Australia and Western Australia to 12.1% in New South Wales; resistance to gentamicin ranged from 1.4% in South Australia to 12.9% in the Northern Territory; and resistance to ciprofloxacin ranged from 2.4% in Queensland to 12.9% in the Northern Territory. For E. cloacae complex, resistance to gentamicin ranged from 0.0% in the Northern Territory, South Australia and Tasmania to 16.0% in the Australian Capital Territory; and resistance to ciprofloxacin ranged from 0.0% in the Northern Territory, South Australia and Tasmania to 5.6% in New South Wales. Table 4.4 Percentage of Escherichia coli resistance, by jurisdiction of testing (blood culture isolates), 2014
– = no data available; ACT = Australian Capital Territory; n = number of isolates tested; NSW = New South Wales; NT = Northern Territory; Qld = Queensland; SA = South Australia; Tas = Tasmania; Vic = Victoria; WA = Western Australia a n = 485 b n = 332 Notes:
1. Resistance determined using European Committee on Antimicrobial Susceptibility Testing interpretive criteria. 2. Not all antimicrobial agents were reported for all species. Source: Australian Group on Antimicrobial Resistance Table 4.5 Percentage of Klebsiella pneumoniae resistance, by jurisdiction of testing (blood culture isolates), 2014
– = no data available; ACT = Australian Capital Territory; NSW = New South Wales; n = number of isolates tested; NT = Northern Territory; Qld = Queensland; SA = South Australia; Tas = Tasmania; Vic = Victoria; WA = Western Australia a n = 109 b n = 96 c n = 137 Notes: 1. Resistance determined using European Committee on Antimicrobial Susceptibility Testing interpretive criteria. 2. Not all antimicrobial agents were reported for all species. Source: Australian Group on Antimicrobial Resistance Table 4.6 Percentage of Enterobacter cloacae complex resistance, by jurisdiction of testing (blood culture isolates), 2014
– = no data available; ACT = Australian Capital Territory; n = number of isolates tested; NSW = New South Wales; NT = Northern Territory; Qld = Queensland; SA = South Australia; Tas = Tasmania; Vic = Victoria; WA = Western Australia a n = 41 b n = 33 Notes:
1. Resistance determined using European Committee on Antimicrobial Susceptibility Testing interpretive criteria. 2. Not all antimicrobial agents were reported for all species. Source: Australian Group on Antimicrobial Resistance
Significantly higher 30-day all-cause mortality occurred when the bacteraemia had its onset in the hospital. For E. coli and K. pneumoniae, the impact of multidrug resistance on 30-day all-cause mortality was small or negligible, but there was a noticeable impact on mortality with E. cloacae complex. This may be due to the smaller range of remaining effective antimicrobials available for treatment of E. cloacae complex. For E. coli and K. pneumoniae, the impact of multidrug resistance on 30-day all-cause mortality was small or negligible, but there was a noticeable impact on mortality with E. cloacae complex. Full data from AGAR surveys of gram-negative bacteria can be found on the AGAR website (see Appendix 3). Table 4.7 Onset setting and 30-day all-cause mortality for the 12 most commonly isolated Enterobacteriaceae species (blood culture isolates), 2014
Source: Australian Group on Antimicrobial Resistance (national) Table 4.8 Onset setting and 30-day all-cause mortality for the three most commonly isolated Enterobacteriaceae species, by multidrug resistance (blood culture isolates), 2014
Note: Multidrug-resistant strains are resistant to three or more antimicrobial classes. Intrinsic resistances were excluded from the definition of multidrug resistance in K. pneumoniae and E. cloacae. Cefazolin was excluded from the definition because minimum inhibitory concentration data is not recorded by some institutions. The antimicrobials used to define multidrug resistance were: 1. E. coli: ampicillin, amoxicillin–clavulanate, piperacillin–tazobactam, ceftriaxone, ceftazidime, cefepime, gentamicin, amikacin, ciprofloxacin, nitrofurantoin, trimethoprim, meropenem 2. K. pneumoniae: amoxicillin–clavulanate, piperacillin–tazobactam, ceftriaxone, ceftazidime, cefepime, gentamicin, amikacin, ciprofloxacin, nitrofurantoin, trimethoprim, meropenem 3. E. cloacae: piperacillin–tazobactam, ceftriaxone, ceftazidime, cefepime, gentamicin, amikacin, ciprofloxacin, nitrofurantoin, trimethoprim, meropenem. Source: Australian Group on Antimicrobial Resistance
ACT = Australian Capital Territory; NSW = New South Wales; NT = Northern Territory; Qld = Queensland; SA = South Australia; Tas = Tasmania; Vic = Victoria; WA = Western Australia Note: The extended-spectrum -lactamase phenotype has a minimum inhibitory concentration >1 mg/mL for ceftriaxone or ceftazidime. Source: Australian Group on Antimicrobial Resistance (public and private hospitals) Data table: Figure 4.9
Yüklə 1,59 Mb. Dostları ilə paylaş:
|
