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of Multi-Drug-Resistant Organisms. The. Alan D. Junkins, PhD, D(ABMM). Sponsored by an educational grant from . Louisville, KY. You know that Pseudomonas aeruginosa from Mr. Jones in 5F? Is that an MDRO?. Why do you want to know?. Why are you asking me?. How should I know?.
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of Multi-Drug-Resistant Organisms The Alan D. Junkins, PhD, D(ABMM) Sponsored by an educational grant from Louisville, KY
You know that Pseudomonas aeruginosa from Mr. Jones in 5F? Is that an MDRO?
Why do you want to know? Why are you asking me? How should I know?
Why do you want to know? • Your own internal monitoring • “We’ve had a 35% increase in MRSA isolates this year.” • For infection control purposes • “All patients with MDR GNB are placed in contact precautions.” • Reporting to authorities • “We have to report all MDROs to the state.”
Why do you want to know? • Your own internal monitoring • “We’ve had a 35% increase in MRSA isolates this year.” • For infection control purposes • “All patients with MDR GNB are placed in contact precautions.” • Reporting to authorities • “We have to report all MDROs to the state. Who defines MDRO? You do, Or whomever you’re producing the data for
Why do you want to know? • Your own internal monitoring • “We’ve had a 35% increase in MRSA isolates this year.” • For infection control purposes • “All patients with MDR GNB are placed in contact precautions.” • Reporting to authorities • “We have to report all MDROs to the state. Who defines MDRO? Your infection control team
Why do you want to know? • Your own internal monitoring • “We’ve had a 35% increase in MRSA isolates this year.” • For infection control purposes • “All patients with MDR GNB are placed in contact precautions.” • Reporting to authorities • “We have to report all MDROs to the state.” Who defines MDRO? NHSN, CDC, State, Parent Company
Hence, the problem… Different people doing the defining… for different reasons… …leads to different definitions.
I know one when I see one… VRE MRSA AmpC ESBL KPC Acinetobacter …well, maybe not.
The Simplest Approach The Not Quite As Simple But Now The Closest Thing We Have to Universally Accepted Approach Multi – drug - resistant Resistant to > 1 drug Non-susceptible to >2 classes of drugs
XDR and PDR Extensively drug resistant Non-susceptible to at least 1 drug in all but two or fewer classes Pan drug resistant Non-susceptible to all agents in all classes
What is a “class” of drugs? Beta-lactams
What is a “class” of drugs? Penicillins Cephalosporins Monobactams Carbapenems
What is a “class” of drugs? 1st gen. Cephalosporins Aminopenicillins Ureidopenicillins 2nd gen. Cephalosporins Carboxypenicillins 3rd gen. Cephalosporins ß-lactamase resistant penicillins 4thgen. Cephalosporins 5th gen. Cephalosporins ß-lactamase inhibitor combinations Cefamycins Carbapenems Monobactams
What is resistance to a class? Yes Yes Yes Yes
What about intrinsic resistances? • Should intrinsic resistance count toward number of classes showing resistance? • Typically chromosomally encoded; those genetic determinants are not easily passed on to other bacteria • But still can be bad boys – bad infections, bugs can be transmitted to others, hard to treat
If we include intrinsic resistances in our definition, then every single Acinetobacter baumannii, Burkholderia cepacia, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia we isolate would be considered MDRO.
If we include intrinsic resistances in our definition, then every single Morganella, Proteus, Providencia, and Serratia marcescens we isolate would be considered MDRO.
22 drugs in 17 classes MDR – NS to at least one drug in at least 3 classes XDR – NS to at least one drug in all but 2 or fewer classes PDR – NS to all drugs in all classes
22 drugs in 17 classes 14 drugs in 13 classes MDR – NS to at least one drug in at least 3 classes XDR – NS to at least one drug in all but 2 or fewer classes PDR – NS to all drugs in all classes
Standardization, but is it practical? MDR – NS to at least one drug in at least 3 classes XDR – NS to at least one drug in all but 2 or fewer classes PDR – NS to all drugs in all classes
Authors recommend additional designations: “Possible XDR” “Possible PDR”
We’ll call this one the “CDC” paper. Based on 2008 SHEA/HICPAC Position Paper published in Inf Control & Hosp Epidemiol, October 2008, vol. 29, no. 10 http://www.cdc.gov/nhsn/PDFs/pscManual/12pscMDRO_CDADcurrent.pdf, January 2013
MDRO Definitions MRSA Resistant to oxacillin, methicillin, or cefoxitin, or positive by an FDA-approved test for mecA on isolated colonies or in specimens MSSA Not a MRSA http://www.cdc.gov/nhsn/PDFs/pscManual/12pscMDRO_CDADcurrent.pdf, January 2013
MDRO Definitions VRE Any Enterococcusresistant to vancomycin or positive by an FDA-approved test for VRE Ceph-R Klebsiella Any Klebsiella non-susceptible to ceftriaxone, cefotaxime, ceftazidime, or cefepime*** ***Based on new breakpoints http://www.cdc.gov/nhsn/PDFs/pscManual/12pscMDRO_CDADcurrent.pdf, January 2013
MDRO Definitions CRE E. coli Non-susceptible to imipenem, meropenem, or doripenem***, or positive by a test for carbapenemase ***Based on new breakpoints CRE Klebsiella http://www.cdc.gov/nhsn/PDFs/pscManual/12pscMDRO_CDADcurrent.pdf, January 2013
MDRO Definitions MDR Acinetobacter http://www.cdc.gov/nhsn/PDFs/pscManual/12pscMDRO_CDADcurrent.pdf, January 2013
Call this one the “CRE Toolkit” Based on new breakpoints Back to CRE http://www.cdc.gov/hai/organisms/cre/cre-toolkit/
But maybe not so straightforward… http://www.cdc.gov/hai/organisms/cre/cre-toolkit/
How many CRE at Norton*?(since January 1, 2010) 13 True Modified Hodge Positive 28 Standard definition from CDC’s “CRE Toolkit” 22 Take away imipenem-NS Proteus, Providencia, Morganella 37 Include ertapenem NS isolates *We are still using the “old” cephalosporin and carbapenem breakpoints.
Mandatory Reporting • Which definition to use? • Labs using old breakpoints • Labs using new breakpoints • Infections only, or include colonization? • Mandatory surveillance? • Which method? • CDC method • Chromogenic media
What We’ve Done • Certain organisms are designated in microbiology laboratory reports as MDROs. • The Microbiology Laboratory makes this determination on the basis of full susceptibility results from the MicroScan and supplemental testing if necessary. • The chief intent is infection control. All patients infected with an isolate reported as an MDRO are put into contact precautions. • We continue to use pre-2009 CLSI breakpoints for cephalosporins and carbapenems with supplemental testing for beta-lactamases as necessary. • We generally do not do surveillance cultures to detect colonization, with the exception of weekly MRSA cultures in the NICU.
Our MDRO Definitions • MRSA – by oxacillin or cefoxitin MIC or by growth on chromogenic medium • VRE – by vancomycin MIC; E. faecalisand E. faecium only • E. coli, Klebsiella, and Proteus mirabilis that produces ESBL enzymes • Certain Enterobacteriaceae that produce plasmid-encoded AmpC enzymes
What about other bugs? Burkholderia cepacia Stenotrophomonas maltophilia Achromobacterxylosoxidans Streptococcus pneumoniae
Is this an MDRO? Staphylococcus aureus No Yes GBGX: CDC:
Is this an MDRO? Staphylococcus aureus Yes Yes? GBGX: CDC:
Is this an MDRO? Enterococcus faecalis Yes No GBGX: CDC:
Is this an MDRO? Enterococcus gallinarum No Yes GBGX: CDC:
Is this an MDRO? Acinetobacter baumannii Yes Yes GBGX: CDC:
Is this an MDRO? Acinetobacter baumannii 1 3 2 4 5 2 1 Yes No GBGX: CDC:
Is this an MDRO? Achromobacterxylosoxidans Species not addressed Species not addressed GBGX: CDC: