The interferon-gamma inducible protein 16 (IFI16) is a nuclear DNA sensor that mediates antiviral responses by activating the inflammasome, triggering an interferon response, and silencing lytic genes of herpesviruses. The last, which helps maintain latency of the oncoherpesvirus Epstein-Barr virus (EBV), is accomplished via H3K9me3 heterochromatinization through unknown mechanisms.

Background: Members of the genus Corynebacterium are increasingly recognized as pathobionts and can be very resistant to antimicrobial agents. Previous studies have demonstrated that Corynebacterium striatum can rapidly develop high-level daptomycin resistance (HLDR) (minimum inhibitory concentration [MIC] ≥256 μg/mL). Here we conducted a multi-center study to assay for this in vitro phenotype in diverse Corynebacterium species. Methods: Corynebacterium clinical isolates (n=157) from four medical centers were evaluated. MIC values to daptomycin, vancomycin, and telavancin were determined before and after overnight exposure to daptomycin to identify isolates able to rapidly develop daptomycin non-susceptibility. To investigate assay reproducibility, 18 isolates were evaluated at three study sites. In addition, stability of daptomycin non-susceptibility was tested using repeated subculture without selective pressure. The impact of different media brands was also investigated. Results: Daptomycin non-susceptibility emerged in 12 of 23 species evaluated in this study (C. afermentans, amycolatum, aurimucosum, bovis, jeikeium, macginleyi, pseudodiphtheriticum, resistens, simulans, striatum, tuberculostearicum, and ulcerans) and was detected in 50 of 157 (31.8%) isolates tested. All isolates displayed low (susceptible) MIC values to vancomycin and telavancin before and after daptomycin exposure. Repeated subculture demonstrated 2 of 9 isolates (22.2%) exhibiting HLDR reverted to a susceptible phenotype. Of 30 isolates tested on three media brands, 13 (43.3%) had differences in daptomycin MIC values between brands. Conclusions: Multiple Corynebacterium species can rapidly develop daptomycin non-susceptibility, including HLDR, after a short daptomycin exposure period.

BackgroundUrine is the most frequently cultured specimen type for the majority of clinical microbiology laboratories. Typically, around 30% of cultures are positive for uropathogens with 70% yielding insignificant or mixed growth. BD is developing a software Urine Culture Application (UCA) for the BD Kiestra Total Laboratory Automation (TLA) system to screen images of urine culture plates, sort them based on growth vs. insignificant growth and also allow for presumptive pathogen identification.MethodsDe-identified urine specimens were inoculated onto BD BBL™ CHROMagar™ Orientation Media (CHROM; BD, Sparks, MD), CHROM/Trypticase™ Soy Agar II with 5% Sheep Blood (TSA) biplate, BD BBL MacConkey II agar, and TSA using the BD Kiestra TLA system. Plates were imaged at 24 hours using the BD Kiestra™ ReadA Compact imaging acquisition software and an algorithm was applied to the images using the UCA (Version 2.0). Semi-quantitative measurements of <100, 100–1,000, 1,000–10,000, 10,000–100,000, and >100,000 cfu/mL growth were determined by UCA for all media types and presumptive ID was determined using CHROM. Manual reading of the images by two technologists was the gold standard for comparison. For discrepant results, a third manual reader was used as an arbitrator.ResultsTesting between 877 and 934 urine specimens on each of five media types using UCA resulted in an exact semi-quantitative agreement with manual reading for 85.5–95.0% of specimens (Table 1). If semi-quantitative values ± one category of agreement are included, the number rises to 98.2–99.4% agreement. Using CHROM for presumptive identification of pure or predominant organisms, UCA was in agreement with manual identification in 251 of 272 cultures (92.3%). Of the 21 discrepant organisms, 19 were classified as “other” by manual reading but were identified as specific organisms by UCA. Definitive organism identification was not performed.ConclusionUCA was able to accurately categorize bacterial growth into five semi-quantitative categories using five media types. Pure and predominant uropathogens were accurately identified from CHROM using UCA. The use of UCA software application may enable laboratories to save time screening urine cultures by allowing more efficient use of technologist time. Disclosures All authors: No reported disclosures.

During the course of infection, human immunodeficiency virus (HIV) maintains a stably integrated reservoir of replication-competent proviruses within the host genome that are unaffected by antiretroviral therapy. Curative advancements rely heavily on targeting the reservoir, though determinants of its evolutionary origins remain ill-supported through current strategies and are often limited by sample variety. Here, we describe a single-cell deoxyribonucleic acid sequencing (scDNA-seq) method, optimized for sequencing of proviral and host DNA from a treatment-interrupted HIV animal model. We report its benefits for improving viral reservoir resolution to support critical evolutionary events otherwise considered unreliable using traditional viral envelope gene signal alone, as well as comparative advantages to existing near-full-length genome sequencing methods. Given the variety of proviral characteristics that may influence viral rebound, scDNA-seq holds immense value in its ability to streamline many of the present-day applications available in viral reservoir studies, such as integration status and putative replication competency.

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Background: Catheter-associated urinary tract infections (CAUTIs) account for >15% of hospital-acquired infections, resulting in increased length of stay and costs. Consequently, methods to improve indwelling urinary catheter (IUC) care and maintenance are warranted to reduce the risk of hospital-acquired CAUTIs. This study was a prospective quality improvement (QI) project to reduce CAUTIs using prepackaged cloths (ReadyCleanse by Medline Industries) and a simple, standardized cleaning process for care and maintenance of IUCs. Methods: This study is an ongoing QI project at NorthShore University HealthSystem, a 4-hospital system located north of Chicago, Illinois, with 750 beds and ∼64,000 annual admissions. The study consists of a 1.5-month staff training on proper product use (phase 1), followed by an intervention using the cloths for IUC care (phase 2). Each package contains 5 individual cloths corresponding to a simple, 5-step, cleansing protocol. IUC care and maintenance are performed twice daily on a routine basis and after each incontinent episode. Beginning July 2018, current practice (soap and wash cloth) was replaced with the ReadyCleanse cloths, and on August 1, 2018, data collection began. Adult patients admitted at all 4 NorthShore Hospitals with an IUC for >24 hours are enrolled in the study. From patient electronic health records, we collected patient demographics, reason for IUC insertion, days of catheter use, and development of CAUTI (according to the NHSN definition). During the intervention, observations of compliance and performance of catheter care were also performed. For the analysis described here, results for the first 14 months of the study were compared to CAUTI numbers from the 14-month period prior to the start of the study (February 2017–March 2018); the data presented represent ∼50% of the planned data collection. Results: As of September 30, 2019, 4,969 patients were prospectively enrolled in the study: 1,491 patients from hospital A, 1,451 from hospital B, 1,091 from hospital C, and 936 from hospital D. Patient demographics for the study cohort were 47% female, with a median age of 77 years and an average of 3.9 catheter days per patient. Systemwide, observational audits for compliance using the cloths averaged 95%. Upon completion of study month 14, 22 CAUTIs had been identified, compared to 26 CAUTIs for the comparison period, indicating a 15% reduction. Conclusion: Implementation of this simple, standardized alternative for IUC care is feasible on a large scale and may have potential for reducing CAUTI rates.Funding: Medline Industries supported this study.Disclosures: None

Background Candida auris is an emerging multidrug-resistant pathogen that can persist in the environment and lead to healthcare-associated outbreaks. Residents of long-term acute care hospitals (LTACHs) are at particular risk for carriage of both MDROs and C. auris. However, there are few data on co-colonization rates of C. auris with other MDROs in LTACHs.MethodsWe conducted a point prevalence survey for MDROs, C. auris and C. difficile in a Chicago LTACH in March 2019. A combined axilla/groin E-swab (Copan) was collected and plated for C. auris isolation using CHROMagar Candida (Hardy). A rectal E-swab (Copan) was collected for C difficile PCR and MDRO detection including Carbapenem-resistant Enterobacteriaceae (CRE), Extended-spectrum B-lactamases (ESBLs) and Vancomycin-resistant Enterococci (VRE). Each swab was plated directly on VACC agar (Vancomycin, Amphotericin B, Ceftazidime, Clindamycin) and CHROMagar ESBL (Hardy). Bruker MALDI-TOF was used for bacterial and yeast identification and disc diffusion method for antimicrobial susceptibility testing. ESBL phenotypic confirmation was done using double-disc synergy method per CLSI guidelines. Carbapenemase production was confirmed using Xpert Carba-R assay (Cepheid). C. difficile PCR was performed using Xpert C. difficile/Epi assay (Cepheid).ResultsOf 38 patients 36 were eligible for the study (2 patients declined). Overall, 26/36 (72%) patients had an MDRO. Eight (22%) patients were positive for C. auris. Eight (22%) patients had ESBLs (2 P. mirabilis and 6 E. coli), six (17%) had CREs that were all blaKPC positive (4 K. pneumonia, 1 E. coli, and K. pneumoniae). Eight (22%) patients were positive for other gram-negative (GN)-MDROs including 1 A. baumanii, 3 P. aeruginosa, 2 E. cloacae, 1 E. asburiae and 1 P. aeruginosa, and A. baumanii. 20 patients (56%) had VRE colonization. Five (14%) were C. difficile PCR positive. 7/ 8 (87.5%) patients with C. auris were also colonized with another MDRO (2 VRE, 1 ESBL, 1 VRE, ESBL and KPC, 1 VRE and GN-MDRO, 1 VRE, ESBL and GN-MDRO, 1 VRE, KPC, and GN-MDRO).ConclusionWe found a high rate of MDRO co-colonization among patients with C. auris carriage. Continuous active surveillance may be appropriate in LTACHs to limit the spread of C. auris and other MDROs.Disclosures All authors: No reported disclosures.