1. A stewards guide to Verigene optimization
Jason M. Pogue, PharmD, BCPS, BCIDP
Clinical Pharmacist, Infectious Diseases
Sinai-Grace Hospital; Detroit Medical Center
Clinical Assistant Professor of Medicine
Wayne State University School of Medicine

2. Objectives
List the organisms and resistance mechanisms that are detected by Verigene BC-GP and BC-GN
Discuss strategies for optimizing the use of Verigene within your institution

3. What is Verigene?
Multiplex PCR test that is run on positive blood cultures
Once blood culture turns positive
Gram stain
Place sample on BC-GP or BC-GN based on results
Results in < 2.5 hours
What do you get?
Organism identification (most common ones)
Key resistance determinants

4. Verigene BC- GP Species Genus Staphylococcus aureus
Staphylococcus spp.
Staphylococcus epidermidis
Streptococcus spp.
Staphylococcus lugdunensis
Listeria spp.
Streptococcus anginosus Group
Streptococcus agalactiae
Resistance determinants
Streptococcus pneumoniae
mec A
Streptococcus pyogenes
van A
Enterococcus faecalis
van B
Enterococcus faecium

5. An example pathway for BC-GP

6. Verigene BC-GP: Impact
Very straightforward and simple to put together a pathway based on results
Impact on optimizing meaningful outcomes limited (time to appropriate therapy, LOS, mortality)
Everyone gets vancomycin and it is active (even if not optimal) against most things
Previous technologies that gave genus/species would lead to appropriate therapy as resistance predictable based off of it
Even simple things like coagulase test, GPC in pairs and chains can drive to appropriate coverage if acted upon
Time to optimal therapy can be improved
Largely driven by quicker de-escalation off of vancomycin
Impact on safety?
Infect Control Hosp Epidemiol 2016;37:1361–1366; Proc (Bayl Univ Med Cent) 2015;28(2):139–143

7. Verigene BC- GN Species Resistance determinants Escherichia coli CTX-M
Klebsiella pneumoniae
KPC
Klebsiella oxytoca
VIM
Pseudomonas aeruginosa
IMP
Genus
NDM
Acinetobacter spp.
OXA
Citrobacter spp.
Enterobacter spp.
Proteus spp.
Can mean different things for different organisms
A. baumannii  OXA-23, 51, 58
Enterobacteriaceae  OXA-48 like
What it picks up versus what it doesn’t isn’t well defined….

8. Verigene BC-GN offers a HUGE opportunity to escalate and improve outcomes!
Informal pathway at the DMC
Organism detected
Resistance determinant
Regimen
Enterobacteriaceae
CTX-M
Ertapenem
KPC
Meropenem/vaborbactam
NDM-1/VIM/IMP
Polymyxin B + ceftazidime/avibactam + aztreonam
OXA
Ceftazidime/avibactam
Acinetobacter
Polymyxin B + minocycline (usually)
P. aeruginosa
IMP/VIM
Enterobacter, Citrobacter spp.
Cefepime, piperacillin/tazobactam (if you are so inclined)

9. J Clin Microbiol. 2016 Jul;54(7):1789-1796

10. “Hospital length of stay was decreased in the post BC-GN group (7 (5-15) days versus 9 (4.5 – 21 days); p = 0.001)”
Eur J Clin Microbiol Infect Dis (10):

11. That’s great but…what do you do when resistance determinants are negative?
Enterobacteriaceae
There are non CTX-M ESBLs
P. aeruginosa
Common beta lactam resistance mechanisms not on that list
A. baumannii
Are all oxacillinases detected??

12. So what would you do?
JJ is a 36 y/o female who presents with urosepsis. She has a history of recurrent UTI, no other details provided. Her vitals and relative lab values in the ED were as follows:
BP: 97/60, Tmax 38.5, HR 110, RR 18
WBC 17.5, Creatinine 1.4 (baseline 0.8)
Patient is started on Vancopime
17 hours later the following information comes back
Blood culture GNR, Verigene (+) K. pneumoniae, resistance determinants negative
No significant changes to the above labs, but patient stable on the floor
ESBL rate at your institution in K. pneumoniae is 23%
Who wants to (in addition to stopping vancomycin)
A) Continue cefepime
B) Escalate (kind of) to ertapenem
C) De-escalate to ceftriaxone
D) I do not know enough information to make this decision

13. Antimicrob Agents Chemother. 2018 Apr 26;62(5).

14. What did we learn?
At both DMC and UMMC absence of key determinants largely rules out resistance to target agents
One notable exception was P. aeruginosa
Antibiogram and severity of illness should drive decisions
And Ryan might have a solution for you in the next talk
These data should NOT be used to justify a similar pathway at your institution
But you can (and should) do the same thing

15. There are a few quirks of Verigene BC-GN to be aware of
Off panel organisms
From time to time we will see off panel organisms
Common considerations: Serratia, Morganella, or in the right population Stenotrophomonas
Also, if anaerobic culture only or GI source – think anaerobes
Polymicrobial GN infections limitations
Dominant organism might only be detected
Different pathogen in untested bottle
Impact on care limited (but not zero)

16. Summary/conclusion
Verigene offers organism ID and the presence/absence of key resistance determinants ~48 hours prior to traditional methodology
Impact on Gram positive BSI is modest
Real benefit is in GNR
Decrease time to appropriate therapy in resistant organisms
Can also allow more rapid de-escalation (or spare unnecessary escalation)
But clinical judgement warranted
We do not have a pathway, even though usually feel comfortable given numbers (even with poly issue). Clinical situation (and other risk factors) need assessed

17. A stewards guide to Verigene optimization
Jason M. Pogue, PharmD, BCPS, BCIDP
Clinical Pharmacist, Infectious Diseases
Sinai-Grace Hospital; Detroit Medical Center
Clinical Assistant Professor of Medicine
Wayne State University School of Medicine