APHL 2019 POSTER ABSTRACTS
Presenter: Lisa Leung, AR Fellow, Maryland Department of Health,
Baltimore, MD, [email protected]
Culture-Based Method to Identify Carbapenem-Resistant
Enterobacteriaceae from Surveillance Studies in
Healthcare Facilities
J. Plemmons, P. Laksanalamai, T. Maruca, J. Ortega, C. Dominguez,
L. Klein, D. Torpey and R.Myers, Maryland Department of Health
Carbapenem-resistant Enterobacteriaceae (CRE) emergence in
hospitals and long-term care facilities has proven to be a major
public health concern due to its high resistance to conventional
treatments and elevated mortality rates of those who become
infected. Correctly identifying CRE, determining mechanisms, and
sequencing for cluster analysis are essential for effective treatment
and preventing further spread in these facilities. Therefore, it
is important to isolate resistant organisms from CRE colonized
patients. Previous attempts to isolate CRE from rectal swabs in
our laboratory have involved selecting by antibiotic resistance,
but have shown little success due to difficulty titrating antibiotic
concentration, resulting in over- or under-selection. To overcome this
problem, we developed a two-step culture approach to identify CRE
from rectal swabs collected during surveillance studies in healthcare
facilities from the Mid-Atlantic region that were determined positive
by Cepheid GeneXpert Carba-R. This new culture based protocol
utilizes inoculation of the rectal swabs in broth enrichment overnight
at 37˚C (with no antibiotic selection) and then plating a standard
dilution onto three different CHROMagar plates to allow for optimal
CRE selection. Different species present on CHROMagar plates
with different colors. Colonies of each color or morphology from
each CHROMagar plate were identified and mechanism-tested
using MALDI-TOF and qPCR. Our qPCR protocol was provided by the
Centers of Disease Control and Prevention (CDC) and tests for the
following Ambler classes: Metallo-beta-lactamase (NDM, VIM, IMP),
Class D (OXA), and Class A (KPC). Selected isolates were sequenced
for further genotypic characterization by whole-genome sequencing
(WGS) to investigate if subsequent infections found in the same
facility were the same strain or were independent infections. This
will determine if there was spread occurring within the facility.
Majority (94.7%) of the rectal swabs had at least one CRE selected
by CHROMagar media. The KPC gene was most commonly detected
(84%) followed by IMP (10%) among the rectal swabs tested. WGS
results suggest that isolates collected from the same surveillance
study are related. Overall, this study demonstrates how effectively
identifying CRE from rectal swabs by a culture based method
will help guide treatment for patients with active infection and
understand the regional spread of CRE.
Presenter: Jessica Plemmons, AR Fellow, Maryland Department of
Health, Baltimore, MD, [email protected]
Public Health Partnership in Response to Resistant
Gonorrhea: Role of Laboratories in Enhancing Local
Capacity Toward Improved Gonococcal Surveillance
M. Khubbar 1 , R. Gomez 1 , J. Weiner 1 , N. Leigh 1 , T. Dasu 1 , T. Maher 2 ,
J. Katrichis 1 , J. Dalby 3 , P. Hunter 3 , J. Pfister 4 , L. Amsterdam 4 , S.
Bhattacharyya 1 ; 1 City of Milwaukee Health Department Laboratory,
2
Wauwatosa Health Department, 3 University of Wisconsin,
4
Wisconsin Division of Public Health
PublicHealthLabs
@APHL
APHL.org
Introduction: Since 2016, the Milwaukee Health Department
Laboratory (MHDL) has collaborated with local and state agencies
and the Centers for Disease Control and Prevention (CDC) to monitor
trends and develop strategies to combat Neisseria gonorrhoeae
(GC) antibiotic resistance (AR). GC culture and antimicrobial
susceptibility testing (AST) data is shared with CDC “Strengthening
the United States Response to Resistant Gonorrhea (SURRG)”
project partners, to support national recommendations for a public
health response to resistant gonorrhea.
Methods: Specimens are collected from genital and non-genital
sites, per defined clinical criteria. At STD clinics, specimens
were collected on InTrays. At non-STD clinics, specimens were
collected using eSwab and transported to MHDL within 24 hours.
NAAT specimens were in APTIMA collection and transport media.
Presumptive identification of isolates was based on presence
of Gram-negative diplococci and oxidase positive colonies, with
apiNH to confirm. AST was performed on GC isolates using Etest
to obtain minimum inhibitory concentration (MIC) for azithromycin
(AZ), cefixime (IX) and ceftriaxone (TXL). Isolates were referred for
Agar Dilution and whole genome sequencing to Texas Antibiotic
Resistance Laboratory Network (ARLN) and CDC.
Results: CDC’s MIC breakpoints were used for enhanced AR
surveillance. All culture and AST data were shared monthly with WI
Division of Health, ARLN and CDC, and in real-time with all partners
for ‘Alert’ and ‘Quick-send Alert’ isolates. From April 2017 through
July 2018, 601 out of 2,317 (25.9%) patient specimens from the
STD clinic and 37 out of 928 (4.0%) from non-STD clinics tested
culture positive. Of those 634 isolates with AST results, 22 (3.5%)
were non-susceptible (NS) to AZ and one (0.2%) to TXL. During the
same time period, GC was detected in 9.07% of 9,265 samples
using molecular assays. Patients NS to any of three antibiotics were
followed up by disease intervention specialists (DIS) to administer
treatment, initiate partner therapy and recommend test of cure. AST
results were available within 7 days of collection 97% of the time.
Conclusion: Increased public health interventions lead to early
detection and treatment of patients NS to antibiotics, with quick
contact tracing by DIS to treat and prevent spread of gonorrhea.
Jurisdictional awareness and capacity building for GC-AST not only
improved local surveillance but ruled out suspect treatment failure
cases in Wisconsin. Real-time detection of GC resistance and strain
typing will improve surveillance toward preventing local outbreaks.
Presenter: Sanjib Bhattacharyya, City of Milwaukee Health
Department, Milwaukee, WI, [email protected]
A Comparison of Biomerieux E-test and Liofilchem MIC Test
Strips Against Carbapenemase-producing Isolates
B. Craft, J. Dale, L. Hovde and P. Snippes Vagnone,
Minnesota Department of Health Public Health
Laboratory
HON.
MENTION
2019
Introduction: With limited treatment options available,
carbapenemase-producing carbapenem resistant
Enterobacteriaceae (CP-CRE) are difficult to treat.
Many of the limited drugs that are available are
a combination of β-lactams and a β-lactamase
inhibitor. In order to test resistance against these drug
combinations, a variety of antimicrobial susceptibility testing (AST)
methods are used. For this study, two types of gradient diffusion
antibiotic test strips were utilized: “E-test” from Biomeriex (Durham,
Summer 2019 LAB MATTERS
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