screening for resistant organisms
TRANSCRIPT
-
7/28/2019 Screening for Resistant Organisms
1/39
Screening for Resistant
Organisms
Dr Koh Tse Hsien
Singapore General Hospital
-
7/28/2019 Screening for Resistant Organisms
2/39
How do you detect resistant
organisms?
Passive surveillance Normal lab results
No extra work or cost
May only pick up tip of the iceberg (20%)
Active surveillance Screening
Picks up colonization
Extra work and cost
-
7/28/2019 Screening for Resistant Organisms
3/39
Why screen?
There is a problem
resistant bacteria affects patient morbidity and
mortality
infections with resistant bacteria increase costs
There is an intervention
isolation of patient
clearance of carriage
empirical treatment
-
7/28/2019 Screening for Resistant Organisms
4/39
What to screen
Vancomycin-resistant Enterococcus (VRE)
Methicillin-resistant Staphylococcus aureus
(MRSA)
Extended-spectrum cephalosporin resistant
Enterobacteriaceae
Carbapenemase-producingEnterobacteriaceae (CPE)
etc..
-
7/28/2019 Screening for Resistant Organisms
5/39
-
7/28/2019 Screening for Resistant Organisms
6/39
Selective agars
Antibiotic content allows selection of
resistance phenotype
Chromogenic indicator may allow presumptive
identification
Takes at least 24 hours
Enrichment broth step? Labor intensive
Allows isolation of strain for typing studies
-
7/28/2019 Screening for Resistant Organisms
7/39
PCR
May be more sensitive
Faster time to result
May be technically complex Expensive
-
7/28/2019 Screening for Resistant Organisms
8/39
http://www.google.com.sg/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=T1nShUv53zAIFM&tbnid=xnyGPlAG2NXJkM:&ved=0CAUQjRw&url=http://www.bio-rad.com/en-se/product/mrsaselect-medium&ei=ALEqUs-cKMWIrQfY04CoDw&bvm=bv.51773540,d.bmk&psig=AFQjCNHmtvx2My8tG3QZxn8uktnG2f09HA&ust=1378615881198045http://www.google.com.sg/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=T1nShUv53zAIFM&tbnid=xnyGPlAG2NXJkM:&ved=0CAUQjRw&url=http://www.bio-rad.com/en-se/product/mrsaselect-medium&ei=ALEqUs-cKMWIrQfY04CoDw&bvm=bv.51773540,d.bmk&psig=AFQjCNHmtvx2My8tG3QZxn8uktnG2f09HA&ust=1378615881198045 -
7/28/2019 Screening for Resistant Organisms
9/39
MRSA
Pooled nose, axilla, (throat), and perinealswab
http://www.bd.com/ds/productCenter/215084.asp
http://www.bio-rad.com/
http://www.google.com.sg/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=T1nShUv53zAIFM&tbnid=xnyGPlAG2NXJkM:&ved=0CAUQjRw&url=http://www.bio-rad.com/en-se/product/mrsaselect-medium&ei=ALEqUs-cKMWIrQfY04CoDw&bvm=bv.51773540,d.bmk&psig=AFQjCNHmtvx2My8tG3QZxn8uktnG2f09HA&ust=1378615881198045http://www.google.com.sg/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=T1nShUv53zAIFM&tbnid=xnyGPlAG2NXJkM:&ved=0CAUQjRw&url=http://www.bio-rad.com/en-se/product/mrsaselect-medium&ei=ALEqUs-cKMWIrQfY04CoDw&bvm=bv.51773540,d.bmk&psig=AFQjCNHmtvx2My8tG3QZxn8uktnG2f09HA&ust=1378615881198045 -
7/28/2019 Screening for Resistant Organisms
10/39
Enrichment or no enrichment?
Adding MRSA broth (ThermoScientific)
increased detection by 50% in SGH samples
But adds one extra days incubation to confirm
positive
http://www.rapidmicrobiology.com/news/603h120p.JPG
-
7/28/2019 Screening for Resistant Organisms
11/39
PCR
http://www.bd.com/geneohm/english/products/max/instrument/
http://www.cepheid.com/tests-and-reagents/clinical-ivd-test/xpert-mrsa
http://www.roche.com/products/product-details.htm?type=product&id=109
-
7/28/2019 Screening for Resistant Organisms
12/39
http://www.cepheidondemand.com/Summer-2011/cover-story.php
-
7/28/2019 Screening for Resistant Organisms
13/39
David, M. Z. et al. 2010. Clin. Microbiol. Rev. 23(3):616-687
FIG. 2. Hypothetical virulence factors in USA300 and other CA-MRSA strains
-
7/28/2019 Screening for Resistant Organisms
14/39
-
7/28/2019 Screening for Resistant Organisms
15/39
-
7/28/2019 Screening for Resistant Organisms
16/39
VRE
Stool or rectal swab
-
7/28/2019 Screening for Resistant Organisms
17/39
-
7/28/2019 Screening for Resistant Organisms
18/39
-
7/28/2019 Screening for Resistant Organisms
19/39
Vitek II
-
7/28/2019 Screening for Resistant Organisms
20/39
-
7/28/2019 Screening for Resistant Organisms
21/39
Magnapure
Qiagen DNA minikit
-
7/28/2019 Screening for Resistant Organisms
22/39
-
7/28/2019 Screening for Resistant Organisms
23/39
-
7/28/2019 Screening for Resistant Organisms
24/39
-
7/28/2019 Screening for Resistant Organisms
25/39
-
7/28/2019 Screening for Resistant Organisms
26/39
-
7/28/2019 Screening for Resistant Organisms
27/39
CPE
Stool or rectal swab
-
7/28/2019 Screening for Resistant Organisms
28/39
-
7/28/2019 Screening for Resistant Organisms
29/39
-
7/28/2019 Screening for Resistant Organisms
30/39
5ml TSB+Meropenem disk
Meropenem 10 g
disk
-
7/28/2019 Screening for Resistant Organisms
31/39
MacConkey Agar with Imipenem DiskImipenem
-
7/28/2019 Screening for Resistant Organisms
32/39
Chromagar KPC
-
7/28/2019 Screening for Resistant Organisms
33/39
ChromID ESBL
Cefpodoxime
-
7/28/2019 Screening for Resistant Organisms
34/39
MAST Adatabs
-
7/28/2019 Screening for Resistant Organisms
35/39
MacConkey +Meropenem 1 mg/L
-
7/28/2019 Screening for Resistant Organisms
36/39
ChromID CARBA
-
7/28/2019 Screening for Resistant Organisms
37/39
-
7/28/2019 Screening for Resistant Organisms
38/39
Direct from stool
-
7/28/2019 Screening for Resistant Organisms
39/39
Questions to ask yourself before
starting surveillance What is the target population?
Which resistant organisms do you want to
identify?
Which method? What body sites to sample?
How long are you going to survey?
Admission surveillance or periodic surveillance? Who pays?
Is there will and money to intervene?