Lab Matters Fall 2023 | Page 98

APHL 2023 POSTER ABSTRACTS

reported sexual exposures . Among 1,652 samples from suspected meningococcal cases , 1,593 ( 96.5 %) bacterial isolates were recovered and 1,472 ( 92.4 %) were confirmed positive for Nm . Of the 1,472 Nm isolates , the majority were pharyngeal ( n = 1342 , 91.2 %) followed by urethral ( n = 104 , 7.1 %), rectal ( n = 25 , 1.7 %) and endocervical ( n = 1 , 0.06 %). In total , 66.7 % of isolates were NG of which 88.4 % were pharyngeal , 9.5 % urethral and 2.3 % rectal . More than 60 % of urethral isolates , 8 % of rectal and 1.7 % pharyngeal isolates were from the US NmNG urethritis clade . Seventy-one percent of urethral NmNG and 2.3 % of pharyngeal NmNG isolates were clonal complex 11 . A few individuals ( n = 81 ) were repeat carriers , defined as same Nm strain collected at the same anatomic site at different visits , 79 / 81 were from pharyngeal samples . Others ( n = 17 ) were mixed carriers , defined as having strains with different CCs ( n = 7 ) or same strain ( n = 10 ) collected at different anatomic sites at the same visit . Overall Nm was detected at both urogenital and extragenital anatomic sites . This systematic surveillance of meningococcal urethritis detected a mixture of CC11 urethritis clade isolates and non-CC11 isolates . Mixed anatomical site carriers carrying oral and genital isolates with the same genetic lineage supports the hypothesis of urogenital transmission and repeat oral carriers inform the possible duration of carriage .

Presenter : GUL Mehnaz Mustafa , mzv2 @ cdc . gov

Comparison of the Accuracy of Antimicrobial Susceptibility Testing ( AST ) for Carbapenem-resistant Enterobacteriaceae using the Biomic V3

J . Roberts , D . Edwards , S . Merid , R . Blackwell and J . Hauser ; District of Columbia Department of Forensic Sciences , Public Health Laboratory Division

Antimicrobial resistance is one of the leading public health concerns globally , occurring with the overuse and / or misuse of antibiotics . The group of carbapenem-resistant organisms ( CRO ), are one of the major contributors in the spread of resistance . CRO are strains of bacteria that are resistant to the antibiotic class , carbapenems , used to treat gram negative bacterial infections . CROs have become a global endemic and very hard to treat , often with outbreaks in healthcare settings causing high mortality rates . Many microbiology laboratories , both clinical and non-clinical , utilize antimicrobial susceptibility test ( AST ) to identify the antibiotics that are effective against the strain of bacteria as well as the minimum inhibitor concentration ( MIC ). AST analysis involves use of the Kirby-Bauer method to measure the zones of inhibition when bacteria is exposed to a specific antibiotic as well as use of the E-test to determine the MIC . Both the Kirby-Bauer and E-test are usually read manually by technologist . The Biomic V3 ( Giles Scientific USA , Santa Barbara , CA ) is an open system that utilizes digital imaging to automate the reading and CLSI / EUCAST interpretation of microbiology test and susceptibilities . Utilization of automated methods enable laboratories to standardize laboratory process with can ultimately improve laboratory efficiency and the quality of results . We evaluated the use of the Biomic V3 to determine the AST profiles for 50 Antimicrobial Resistance laboratory Network ( ARLN ) CRO isolates provided by the CDC . We compared manual reading of Kirby Bauer and E-test profiles with the automated Biomic reading of the zones of inhibition and Etest MICs . In this study , we demonstrate that there was very minimal error between the two methodologies and the readings were comparable . Thus , use of automated readings for AST would be a valuable time saving method to for both , accuracy and standardization .

Presenter : Jamal Roberts , jrob9814 @ gmail . com

Development of Candida auris Surveillance RT-PCR Test in a Prison Hospital Setting

F . Cerqueira , T . York , M . DeMaet , J . Patel , P . Ren ; The University of Texas Medical Branch

Since its detection in 2009 in Japan , Candida auris has emerged as an often multidrug-resistant fungal pathogen associated with global outbreaks . Most notably , invasive C . auris nosocomial infections can cause high-mortality rates in healthcare facilities . C . auris can persist on environmental surfaces and spread from asymptomatic colonized patients to immunocompromised patients who are more susceptible to infection . The US Centers for Disease Control for Disease Control and Prevention put forth guidelines to screen for C . auris within the high-risk patient population . Following this guidance , our facility implemented a systematic C . auris screening protocol for high risk patients in November 2021 using the routine fungal culture method . A breach in this protocol was discovered in July 2022 , when a patient admitted to our healthcare system ’ s adjoining acute-care prison hospital was identified with C . auris fungemia . Due to this discovery , mass screening of all patients within the prison hospital was conducted and additional patients were found to be colonized with C . auris . However , the Infection Control team found that the collection to results turnaround time ( TAT ) of C . auris surveillance cultures was extended , impacting patient care during the outbreak . To shorten the TAT and improve patient care , we developed and validated an RT-PCR laboratory-developed test ( LDT ) on the Hologic Open Access Fusion platform for the detection of C . auris DNA from environmental and patient surveillance specimens . During the assay validation , our LDT detected 9 / 9 C . auris culturepositive samples . Additionally , C . auris DNA was detected in 9 / 139 C . auris culture-negative samples , thus indicating that the RT-PCR test has increased sensitivity compared to the traditional culture method . In addition , implementing this LDT reduced the TAT from 72 to 24.8 hours . With the adoption of this assay , our infection control professionals have been able to identify and isolate C . auris colonized patients more efficiently . Additionally , rooms previously occupied by a C . auris -positive patient can be made available for a new patient sooner after successful decontamination . However , one critical limitation of this molecular technique is the inability to determine whether the detected C . auris DNA originates from live or dead yeast . Therefore , further cleaning and / or the reflex of C . auris culture is needed after a positive molecular test . With the collaboration of our laboratory and institutional Infection Control team , we have demonstrated that multidisciplinary efforts were effective in improving the TAT and sensitivity of the C . auris surveillance testing process within our healthcare system .

Presenter : Filipe Cerqueira , fmcerque @ utmb . edu