Lab Matters Summer 2019 - Page 65

APHL 2019 POSTER ABSTRACTS Presenter: Lisa Leung, AR Fellow, Maryland Department of Health, Baltimore, MD, 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, 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 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, 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 63