BD Diagnostics Research Articles

Criteria for second generation comparator tests in validation of novel HPV DNA tests for use in cervical cancer screening.

While HC2 and GP5+/6+ PCR-EIA were pivotal in test validation of new HPV assays, they represent the first generation of comparator tests based upon technologies that are not in widespread use anymore. In the current guideline, criteria for second-generation comparator tests are presented that include more detailed resolution of HPV genotypes. Second-generation comparator tests should preferentially target only the 12 genotypes classified as carcinogenic (IARC-group I), and show consistent non-inferior sensitivity for CIN2+ and CIN3+ and specificity for ≤CIN1 compared to one of the first-generations comparators, in at least three validation studies using benchmarks of 0.95 for relative sensitivity and 0.98 for relative specificity. Validation should take into account used storage media and other sample handling procedures. Meta-analyses were conducted to identify the assays that fulfill these stringent criteria. Four tests fulfilled the new criteria: (1) RealTime High-Risk HPV Test (Abbott), (2) Cobas-4800 HPV test (Roche Molecular System), (3) Onclarity HPV Assay (BD Diagnostics), and (4) Anyplex II HPV HR Detection (Seegene), each evaluated in three to six studies. Whereas the four assays target 14 carcinogenic genotypes, the first two identify separately HPV16 and 18, the third assay identifies five types separately and the fourth identifies all the types separately.

Hospital-Associated Transmission of Candida auris from Adult to Pediatric Patient

Background: Candida auris, an emerging multidrug-resistant fungus, is often difficult to control in hospital outbreaks. We report the hospital investigation and findings of a transmission of C. auris from patients hospitalized in an adult unit to a pediatric unit, the first in Maryland. Methods: Between June and September 2023, C. auris was recovered from two patients admitted to an adult Neuroscience Intensive Care Unit (ICU) and a patient admitted to a pediatric ICU. Infection control initiated an investigation involving staff interviews, observations and chart reviews. Cases were defined as any patient with clinical or surveillance cultures growing C. auris. Point prevalence surveillance was conducted by collecting nares and composite axilla/groin swabs from patients on the affected units. Environmental cultures collected using moistened E-Swabs (Copan, Murrieta, CA) from shared supplies were plated on CHROMagar Candida (BD, Sparks, MD). C. auris isolates from patients hospitalized at the facility between February 2022 and October 2023 were analyzed by WGS for relatedness. WGS was performed using Illumina NextSeq 300 bp paired-end sequencing (Illumina, San Diego, CA). Single nucleotide polymorphism (SNP) analysis was performed by comparing raw reads to the reference C. auris B8441 genome for subsequent clustering analysis (Ares Genetics, Vienna, Austria). Results: WGS demonstrated isolates from two adults and one pediatric patient were less than three SNPs different, suggesting a shared isolate. One additional pediatric case was identified from surveillance cultures collected from 27 patients. Investigation into possible transmission routes revealed healthcare personnel serving both units, specifically clinical teams and continuous electroencephalography (cEEG) technologists. Additionally, cEEG equipment was used on both adult and pediatric patients and twelve equipment surface swabs and three samples each of measuring tape and gel were collected. C. auris was not isolated, however sensitivity of environmental sampling is unclear and suspicion for possible fomite/environmental transmission persisted. Other possible transmission routes included gaps in hand hygiene, isolation, disinfection of shared equipment, and reuse of single-use items. Interventions included improving and monitoring infection prevention practices, educating multi-disciplinary personnel and heightened environmental cleaning. Conclusion: This case highlights the feasibility of transmission of C. auris between patients admitted to a geographically distant unit. Our investigation revealed multiple possible routes of transmission including direct contact (from healthcare personnel or equipment) or indirect environmental sources. Prevention of hospital-associated C. auris transmission likely necessitates meticulous adherence to hand hygiene, contact precautions, and careful cleaning and disinfection of patient environments and equipment used by all disciplines.Disclosure: Patricia Simner: Research Contracts: BD Diagnostics, OpGen Inc., Qiagen Sciences Inc, T2 Diagnostics, Accelerate Diagnostics; Research Collaborators:Ares Genetics, CosmosID, IDbyDNA, Illumina; Consulting: OpGen Inc., BD Diagnostics, Shionogi Inc., GeneCapture, Qiagen Sciences Inc, Entasis, Day Zero Diagnostics, Next Gen Diagnostics

Evaluation of Vulnerabilities for the Spread of Carbapenem Resistant Organisms at Five Hospitals in India

Background: The 2022 WHO global survey on infection prevention and control (IPC) exposes significant gaps in IPC in the WHO Southeast Asia region. A better understanding of IPC vulnerabilities will inform improvement initiatives. We describe an evaluation of IPC practices known to prevent and contain carbapenem-resistant organisms (CROs) at hospitals participating in the United States Centers for Disease Control Global Action in Healthcare Network –Antimicrobial Resistance in India. Prior hospital evaluations suggest resistance to carbapenems among gram-negative isolates is up to 45%. Methods: We conducted a mixed methods evaluation including cross-sectional surveys, semi-structured interviews, and site observations at five hospitals (one government, two private tertiary care, and two private teaching) located in three cities. The number of hospital beds ranged from 362 to 2,011. Hospital and IPC program characteristics, and CRO prevention and containment activities were examined virtually. Site observations focused on hand hygiene, environmental cleaning, personal protective equipment (PPE), CRO containment practices and use of water for patient care. Results: All sites had IPC programs with established policies and qualified IPC staff. The IPC nurse-to-bed ratio ranged from 1:73 to 1:432 (mean, 1:209). Due to the integral role of microbiology staff in IPC at these hospitals, the two departments had strong communication channels associated with CRO identification. Screening for CRO colonization, if done, targeted patients from outside hospitals. Three of the five hospitals routinely implemented contact precautions for patients with identified CROs, displayed isolation signage at the bedside, and provided adequate PPE at point-of-use; however, all sites reported barriers to effective isolation and/or cohorting patients with CROs. Timely communication of CROs to clinical staff varied and no sites effectively relayed CRO status upon patient discharge to another facility. IPC teams identified gaps in environmental cleaning procedures and practices related to medical devices and equipment. All sites used alternatives to tap water for clinical care and sink etiquette was evident. Each IPC team performed audits of patient isolation and hand hygiene practices. Despite the considerable proportion of IPC resources dedicated to daily education and feedback in clinical areas, the IPC teams reported that improvement was often difficult to achieve. Conclusion: Given the high burden of CROs and limited IPC resources, detailed knowledge of IPC opportunities for improvement will help hospitals target novel interventions for CRO prevention and containment. Further investigation of colonization rates and effective performance improvement methods in these settings is needed.Disclosure: Patricia Simner: Research Contracts: BD Diagnostics, OpGen Inc., Qiagen Sciences Inc, T2 Diagnostics, Accelerate Diagnostics; Research Collaborators:Ares Genetics, CosmosID, IDbyDNA, Illumina; Consulting: OpGen Inc., BD Diagnostics, Shionogi Inc., GeneCapture, Qiagen Sciences Inc, Entasis, Day Zero Diagnostics, Next Gen Diagnostics

Validation of a new extraction-free real-time PCR test to detect MPOX virus

The monkeypox (Mpox) virus has raised significant concerns given its recent spread with an increasing number of confirmed cases worldwide. In this study, we evaluated the performance of a laboratory developed test (LDT) using BioGX Xfree hMPXV/OPXV reagents for the qualitative detection of non-variola Orthopoxviruses and Mpox virus DNA, in swabs from human pustular or vesicular rash specimens. Analytical and clinical testing analysis were carried out on two different platforms: the BD MAX™ System (BD Diagnostics) and the new pixl.16 Real-Time PCR Platform (BioGX), using a synthetic Mpox virus DNA (ATCC VR-3270SD) and residual clinical samples previously identified with an EUA approved Mpox real-time PCR assay. In the end, the Xfree hMPXV/OPXV LDT proved to be a sensitive, specific, and reproducible test for the detection of Mpox on both platforms evaluated with the pixl.16 having an advantage of a small footprint and providing faster TAT facilitated by an extraction-free workflow.

No additional risk of congenital anomalies after first-trimester dydrogesterone use: a systematic review and meta-analysis.

No additional risk of congenital anomalies after first-trimester dydrogesterone use: a systematic review and meta-analysis.

Diagnosis of brain death in Germany-Implementation of the guidelines of the German Medical Association

The 4th update of the guidelines of the German Medical Association on the diagnosis of irreversible loss of brain function (brain death, BD) has introduced important new regulations regarding the required qualification of the examiners, approved procedures for ancillary testing, and aclarification regarding the sequencing of diagnostic steps. Investigation of the implementation and practical effects on the diagnosis of brain death. Descriptive evaluation of the routine documentation of the German Organ Procurement Organization, comparing the periods July 2011-June 2015 (3rd update) and July 2015-June 2019 (4th update). Patient numbers decreased from 6100 to 5403. The largest decrease affected hospitals without neurosurgery. Children were not affected. With the 4th update, clinical diagnostics were increasingly performed during on-call hours by external neurologists. Of the patients 83.8% now received ancillary tests compared to 80.1% previously. Computed tomography angiography (CTA), first introduced in the 4th update, was applied in 23.2% and established complete loss of cerebral circulation in 89.4%. The time between first documentation of the clinical signs of BD and certification of BD increased from 7.0 ± 12.7 h to 8.2 ± 14.2 h. The diagnosis was slightly less frequent with 95.3% compared to 96.6%. The updated standards were implemented in accordance with the guidelines. The demand for external consulting neurologists and neurosurgeons as well as the time required for BD assessment have increased. Negative effects on pediatric BD diagnostics were not apparent. CTA is widely and successfully used in adults as anew ancillary diagnostic procedure.

Investigation of the Frequency of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and Mycoplasma genitalium in Men Living with HIV in Terms of Sociodemographic Characteristics and Behavioral Risk Factors

The aim of this study was to investigate the frequency of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and Mycoplasma genitalium in men living with HIV in terms of sociodemographic characteristics and behavioral risk factors. In this cross-sectional, single center study, all HIV-infected male patients, aged ≥ 18 years, including those being followed-up (n= 142) and the new admissions (n= 16) at Hacettepe University, Department of Infectious Diseases between March 1st, 2017 and May 1st, 2018 were included. After obtaining the informed consent form; age, follow-up days in STI-clinic, marital status, education, employment status; STI-related sign and symptoms, prior STI diagnosis, multiple sexual partners during the last year, exchanging sex for money, sexual orientation, drug use, condom use with regular and casual partner and also risk factors regarding partners were inquired as behavioural risk factors. A sample of first-voided urine of each participant was tested for the presence of Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and Mycoplasma genitalium by using nucleic acid amplification test (NAAT) (BD-MAX system, BD Diagnostics, USA) and BD MAX Mycoplasma-Ureaplasma-OSR for BioGX, (BD Diagnostics, The Netherlands). All participants living with HIV, men who have sex with men (MSM) and heterosexual men were grouped as STI-positive and STI-negative and compared. For all statistical analysis, SPSS 24 software was used. During the period of 14 months; the data was determined as follows: median follow-up time was 1138 (IQR= 159.5- 1494.5) days, median age was 35 (IQR= 28-42) years, 73.3% were single, 68.3% were at least college graduates or had higher educational attainment, 78.1% were currently employed. Of the participants, 26.9% reported STI-related sign and symptoms, 50.0% at least one STI episode in the past. Nine (5.6%) M.genitalium, five (3.1%) N.gonorrhoeae, and four (2.5%) C.trachomatis were detected in the urine samples of 17 (10.7%) individuals. N.gonorrhoeae and C.trachomatis were detected simultaneously in only one patient's urine sample. STI-positive patients (n= 17) were determined to be younger compared to STI-negative group [(p= 0.02; 27 years (IQR= 24-37) vs 35 years (IQR= 28-42)], had prominent STI-related signs and symptoms (p< 0.001) and had more multiple sexual partners (p= 0.03). The median CD4+ T lymphocyte count were relatively lower (p= 0.03) in STI-positive patients and plasma HIV RNA level was higher compared to the STI-negative participants (p= 0.05). STI-positive MSM group were younger [p= 0.01; 26 years (IQR= 23.5-29) vs 33 years, (IQR= 28-40)], STI-related signs and symptoms were more prominent (p= 0.02), the frequency of exchanging sex for money/drugs among their partners (p= 0.03) was higher compared to their STI-negative counterparts. Among STI-positive heterosexual patients, the presence of STI-related signs and symptoms (p= 0.04), drug use among their partners (p= 0.04) and plasma HIV RNA level (p<0.01) were significantly higher. STI was identified as an important health problem in this series of men living with HIV, 63.0% of whom had MSM and had a relatively high education level and socioeconomic status. Young age, having multiple partners, drug use, exchanging sex for money/drugs were prominent among the participants and their partners. Public health studies should focus on preventing STIs in young people living with HIV who have behavioral risk factors.

Evaluation of the BD Phoenix CPO Detect Test for the detection of carbapenemase-producing Enterobacterales.

Aims: This study aimed to evaluate the performance of the BD PhoenixCPO Detect Test (BD Diagnostic Systems) for the detection and classification of carbapenemase-mediated carbapenem resistance. Methods: A total of 447 Enterobacterales strains were included in the study. All strains were tested with the BD Phoenix CPO Detect Test and the modified carbapenem inactivation method. Results: Carbapenemase production was detected in 157 of 159 carbapenemase producers, including 95.7% of class B and 99.2% of class D isolates using the BD Phoenix CPO Detect Test. BD Phoenix CPO Detect has a sensitivity of 98.7% and a specificity of 95.5% in detecting carbapenemase production. Conclusion: The classification of OXA-48 and class B carbapenemases, the most common carbapenemases circulating in Turkey, was highly accurate.

Resistance Pattern in Mostly Gram-negative Bacteria Causing Urinary Tract Infections.

The antimicrobial prescription in urinary tract infections (UTI) is driven by local data on its pathogenic spectrum and the resistance pattern exhibited by the disease-causing pathogens. We aimed to determine the bacteriological diversity of UTI causing pathogens and antimicrobial resistance in mostly gram-negative bacteria. This retrospective hospital-based cross-sectional study analyzed the culture and sensitivity reports of urine samples from a referral centre in the Aljouf region of Saudi Arabia. All the antibiograms from January 1, 2020, to December 31st 2020, were included. The bacterial identification and antimicrobial testing were carried out by the BD Phoenix system (BD Diagnostics, Sparks, MD, USA). Antimicrobial testing was performed as per the Clinical and Laboratory Standard Institute recommendations. Frequencies of multidrug- and extensive drug resistance were calculated. Of the 1334 non-duplicate urine samples received, 422 (31.6%) bacterial growths were observed. Of these, 383 (90.8%) and 39 (9.2%) were gram-negative and gram-positive bacterial isolations, respectively. E. coli 161 (38.1%), K. pneumoniae 97 (23.0%), and E. faecalis 18 (4.3%) were frequent aetiologies of UTI. 309 (80.7%) of gram-negative bacteria were multidrug-resistant including 88 (23.0%) extensively drug-resistant. Overall, a resistance rate of > 55 % to 1st through 4th generation cephalosporins was observed except for cefoxitin (43.7%). A resistance rate of 37.6% was observed towards carbapenems, with the lowest rate (34.0%) to meropenem. Multi-drug resistant gram-negative bacteria dominate the pathogenic spectrum of UTI in the region. A high resistance rate to cephalosporins and carbapenems exists in gram-negative organisms, causing UTI.

Impact of Helicobacter pylori virulence markers on clinical outcomes in adult populations.

In recent years, associations between specific virulence markers of Helicobacter pylori (H. pylori) and gastrointestinal disorders have been suggested. To investigate the presence of virulence factors including vacuolating cytotoxin A genotypes (s1m1, s1m2, s2m1, and s2m2), cytotoxin-associated gene A (CagA), and urease activity in H. pylori strains isolated from Arab and Jewish populations in northern Israel and to assess associations between these factors and patients' demographics and clinical outcomes. Patients (n = 108) who underwent gastroscopy at the Baruch Padeh Medical Center, Poriya due to symptomatic gastroduodenal pathologies as part of H. pylori diagnosis were enrolled in the study. Gastric biopsy specimens were collected from the antrum of the stomach. Clinical condition was assessed by clinical pathology tests. Bacteria were isolated on modified BD Helicobacter Agar (BD Diagnostics, Sparks, MD, United States). Bacterial DNA was extracted, and PCR was performed to detect CagA and vacuolating cytotoxin A genes. Urease activity was assessed using a rapid urease test. A significant correlation was found between disease severity and patient ethnicity (P = 0.002). A significant correlation was found between CagA presence and the s1m1 genotype (P = 0.02), which is considered the most virulent genotype. Further, a higher level of urease activity was associated with isolates originating from the Jewish population. Moreover, higher urease activity levels were measured among CagA-/s1m1 and CagA-/s2m2 isolates. Our study highlights the importance of incorporating molecular methods for detection of virulence markers of H. pylori in order to tailor optimal treatments for each patient. Further investigation should be performed regarding associations between H. pylori virulence factors and ethnicity.

561. Methicillin-Resistant Staphylococcus aureus is Decreasing in Community-Onset Pediatric Infections Treated at a Mid-Atlantic Health System

Abstract Background Hospitalizations due to soft tissue methicillin resistant S. aureus (MRSA) infections are decreasing nationally. Analyzing trends in pediatric community-onset (CO) S. aureus infections is needed to inform empiric antibiotic selection in the Emergency Department and outpatient settings. Methods We identified all cultures growing S. aureus between January 1, 2014 and December 31, 2020 in the Johns Hopkins Hospital microbiology laboratory that services an academic medical center, a mid-level teaching hospital, and a community hospital. Patients were included if they were ≤18 years of age or treated in a pediatric location. Cultures that likely represented colonization, such as nasal swabs, throat swabs, or sputum were excluded. Patients hospitalized within 2 calendar days of culture collection were defined as treated in-hospital. All others were defined as treated outpatient. CO infection was defined as a culture obtained within 3 days of hospitalization or from children not hospitalized. Only the first culture per patient per quarter was included. Cochran Armitage test was used to analyze trends in antibiotic susceptibilities. Results 3517 cultures obtained from 3078 patients were included. 3208 cultures (91%) were CO. Of CO cultures, 2517 (78.5%) were treated in an outpatient setting and 691 (21.5%) were treated in-hospital. There was a 74% decrease in the number of CO S. aureus cultures during the study period: 751 in 2014 to 191 in 2020. Comparing CO cultures from 2014 and 2020, methicillin susceptibility increased from 59.5% to 67% overall (p = 0.007), 59.4% to 63.8% in outpatient treated cultures (p = 0.07), and 60% to 76% among in-hospital treated cultures (p =0.02). Methicillin susceptibility from CO soft tissue sources remained about 60% during the study period with no significant change in trend. When soft tissue sources were excluded from CO cultures, methicillin susceptibility increased from 61.7% in 2014 to 84.1% in 2020 (p = 0.01). Within CO blood cultures, methicillin susceptibility increased from 86.7% to 92.3% (p = 0.4). Conclusion In a regional health system, CO pediatric MRSA incidence is decreasing. Although the majority of CO bloodstream S. aureus infections are methicillin susceptible, MRSA continues to cause up to 40% of S. aureus soft tissue infections. Disclosures Aaron Milstone, MD, Merck: Grant/Research Support Karen C. Carroll, MD, Abbott Diagnostics: Advisor/Consultant|BD Diagnostics: Advisor/Consultant|BD Diagnostics: Grant/Research Support|BioRad, Inc: Grant/Research Support|Meridian Biosciences: Grant/Research Support|Roche Diagnostics: Advisor/Consultant|Scanogen, Inc: Advisor/Consultant|Scanogen, Inc: Grant/Research Support|Thermo Fisher, Inc: Advisor/Consultant.

Complete Genome Sequence of Vibrio maritimus BH16, a Siderophore-Producing Mutualistic Bacterium Isolated from Diatom Skeletonema costatum.

Complete Genome Sequence of Vibrio maritimus BH16, a Siderophore-Producing Mutualistic Bacterium Isolated from Diatom Skeletonema costatum.

Culture and culture-independent diagnostic tests in Campylobacter enteritis.

Campylobacter infections are among the most common causes of bacterial enteritis. This study aims to determine the sensitivity, specificity and positive predictive values (PPV) of culture and culture-independent tests for the diagnosis of Campylobacter enteritis. A total of 400 stool samples were included in the study. BD MAX enteric bacterial panel (BD Diagnostics, Franklin Lakes, NJ, USA) and EntericBio Gastro Panel II (Serosep, Limerick, Ireland) were used as commercial molecular tests. RIDA®QUICK Campylobacter (R-Biopharm, Darmstadt,, Germany) and CerTest (Biotec, Zaragoza, Spain) were used to detect Campylobacter antigens. Samples were cultured in CCDA media and subjected to bacterial identification by mass spectrometry. Among the 400 specimens, 41 (10.2%) were evaluated as Campylobacter positive; 21 were culture-positive and 20 were detected as positive by both PCR methods. Of the 21 isolates grown in culture, 16 (76.2%) were identified as C. jejuni and 5 (23.8%) as C. coli. While all 21 culture-positive specimens were detected as positive by both molecular tests, 18 of the specimens were found positive by RidaQuick, and 16 by Certest ICA. Of the 20 culture-negative Campylobacter cases, 18 were positive by RidaQuick and 12 by Certest ICA. Sensitivities of culture, ICA-RidaQuick and ICA-CerTest were 51.2%, 87.8 and 68.3, respectively. The specificities of all tests were in the range of 90-100 %. PPV of molecular tests, ICA-RidaQuick and ICA-CerTest were > 95%, 72 % and 48.3 %, respectively. Molecular tests were superior to culture and ICA in terms of sensitivity, specificity, and positive predictive value.

The Prevalence of Human Papillomavirus-Positive Oropharyngeal Squamous Cell Carcinoma at One of the Largest Tertiary Care Centers in Sub-Saharan Africa.

Limited data exist on the prevalence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma in sub-Saharan Africa. To determine the prevalence of HPV-positive oropharyngeal squamous cell carcinoma at a large tertiary care center in South Africa. A total of 266 oropharyngeal squamous cell carcinomas diagnosed during an 11-year period (2007-2017) were selected for evaluation. Cases staining positive for p16 immunohistochemistry were evaluated for high-risk HPV using the BD Onclarity assay (BD Diagnostics, Sparks, Maryland). Of 266 oropharyngeal squamous cell carcinomas, 14% (n = 36) were positive for p16. Polymerase chain reaction for high-risk HPV performed on the p16-positive cases was negative in 23 cases and positive in 13 cases (13 of 266; 5%). p16 showed a positive predictive value of 36.1%. The HPV subtypes were HPV-16 (n = 10), HPV-18 (n = 1), HPV-52 (n = 1), and HPV-31 (n = 1). Human papillomavirus-positive cases occurred in 10 men and 3 women (mean age, 51 years) and arose from the tonsil (n = 10) or base of the tongue (n = 3). The HPV-positive cases were non-keratinizing (n = 10) or partially keratinizing (n = 1). Partially/nonkeratinizing cases revealed a modest improvement in p16 positive predictive value (11 of 21; 52.4%). The presence of high-risk HPV in 5% of cases suggests that high-risk HPV is a minor etiologic agent in oropharyngeal squamous cell carcinoma in this region. Given its suboptimal positive predictive value, p16 is not a reliable marker for high-risk HPV infection in this region. When p16 is positive, HPV-specific testing is necessary. The identification of less common high-risk HPV types, HPV-52 and HPV-31, may influence current local vaccination strategies.

Resistance Patterns of Gram-Negative Bacteria Recovered from Clinical Specimens of Intensive Care Patients.

Intensive care units are complex environments favoring high resistance in microorganisms. This study evaluated the resistance and the distribution dynamics of resistant Gram-negative bacteria (GNB) in patients admitted to intensive care units. This retrospective, record-based, cross-sectional study analyzed all of the antibiograms of patients admitted to the ICUs. The BD Phoenix system (BD Diagnostics, Sparks, MD, USA) was used for bacterial identification and antimicrobial testing. Clinical and Laboratory Standard Institute recommendations were used for antimicrobial testing. Frequencies and percentages of multidrug and pan-drug resistance were calculated. A total of 570 bacterial growths were observed, out of which 437 (76.7%) were of GNB. K. pneumoniae (21.0%), P. aeruginosa (11.8%), and Staphylococcus aureus (13.2%) were the most frequent disease-causing bacteria in intensive care patients. Resistance rates of 73.2% and 70.1% were observed for third- and fourth-generation cephalosporins, respectively, while 48.2% carbapenem and > 65% fluoroquinolones resistance rates were observed. Amikacin was the most effective antibiotic, with a sensitivity rate of 69.5%. A total of 372 (85.1%) of GNB were multidrug resistant. The majority of infections in intensive care patients are caused by multidrug-resistant (MDR) Gram-negative bacteria. Female gender and advancing age are factors favoring MDR. Enhanced surveillance and strengthening of the antimicrobial stewardship program are warranted.

Difference in Susceptibility Between Carbapenemase- and Non–Carbapenemase-Producing Carbapenem-Resistant Enterobacteriaceae

Background: Carbapenem-resistant Enterobacteriaceae (CRE) remain among the most urgent infectious threats according to the CDC Threats Reports. Although focus has often been placed on carbapenemase-producing phenotypes, there is increasing interest in distinguishing the optimal treatment and outcomes of carbapenemase-producing (CP) and non–carbapenemase-producing (NCP) CRE. We compare antimicrobial susceptibility patterns between CP-CRE and NCP-CRE isolated from patients at our academic medical center. Methods: All CRE isolates of Enterobacter cloacae, Escherichia coli, Klebsiella aerogenes, K. oxytoca, and K. pneumoniae in adult inpatients from 2010 to 2019 were included in this study. Susceptibility testing was performed using the BD Phoenix Automated System (BD Diagnostics, Sparks, MD). CLSI susceptibility break points were utilized in the susceptibility analyses of all antimicrobials tested. To determine carbapenemase production, isolates resistant only to ertapenem were considered NCP-CRE, and those resistant to both ertapenem and meropenem were considered CP-CRE. Statistical comparisons of susceptibility profiles were performed using either the χ2 test or the Fisher exact test. All data preprocessing and statistical analyses were performed using Python software. Results: Over the decade, we identified 291 CRE isolates (216 isolates resistant only to ertapenem and 75 resistant to ertapenem and meropenem). The ertapenem-resistant–only phenotype comprises ~66% of the total CRE population and is largely composed of E. cloacae (67%). As expected, most β-lactam susceptibilities were negligibly low between the 2 groups; however, other clinically relevant antimicrobials (aminoglycosides, fluoroquinolones, and sulfamethoxazole/trimethoprim) exhibited starkly different susceptibility profiles (P value Conclusions: These findings suggest that the most predominant CRE phenotype at our institution is not carbapenemase production. Evaluation of outcomes between CP- and NCP-CRE should be pursued further. The large differences in the MIC distributions may lead to differing outcomes for the affected patients.Funding: NoDisclosures: None

Evaluation of Two Commercial Kits for Rapid Detection and Typing of Carbapenemase in Carbapenem-Resistant Enterobacterales

Background: Rapid detection of carbapenemase-producing Enterobacterales (CPE) is desirable to guide antimicrobial therapy and infection control. The NG-Test Carba5 (Carba5; NG Biotech, France) rapid multiplex lateral flow immunoassay and BD MAX Check-Points CPO Assay (CPO; BD Diagnostic Systems, USA) fully automated real-time PCR assay were evaluated for the detection of KPC, NDM, VIM, IMP, and OXA-48-like group in a culture colony compared to genotyping using conventional PCR. Methods: Among the clinical isolates of carbapenem-resistant Enterobacterales (CRE) collected from 2013 to 2019, up to 20 isolates for each carbapenemase type, and approximately 60 carbapenemase-negative CRE were enrolled. Genotyping of carbapenemases were performed using single-target PCR for KPC, NDM, and OXA-48-like group and the multiplex PCR for VIM, IMP, GIM, SIM, and SPM. All isolates were tested with Carba5 and CPO. The discrepant results were resolved by single-target specific conventional PCR or GeneXpert Carba-R Assay (Carba-R; Cepheid, USA). Results: Of 147 CREs, 82 were CPE (55.8%) including 20 KPC, 22 NDM, 17 VIM, three IMP, and 13 OXA-48-like group, and seven double carbapenemase-positive (three KPC/VIM, two NDM/ VIM, one KPC/NDM, and one NDM/OXA-48-like group) isolates. Carba5 and CPO detected all CPE correctly along with two more IMP-producing CPE. The sensitivity and specificity of both kits were equally 100% and 97%. Two false IMP-positives were confirmed IMP-positive with Carba-R and IMP-specific single-target PCR. Conclusion: Carba5 and CPO reliably detect and differentiate five common carbapenemases in cultured colonies. Carba5, faster and simpler, is preferred as a spot test.

Live SARS‐CoV‐2 is difficult to detect in patient aerosols

Live SARS‐CoV‐2 is difficult to detect in patient aerosols

The combination of Demodex folliculorum and Aerobic Bacteria in the Etiopathogenesis of Chronic Blepharitis

Abstract&#x0D; Aims: This study was conducted to investigate the presence of thecombination of Demodex folliculorum and aerobic bacteria in patients with chronic blepharitis.&#x0D; Material and Methods: Seventy-one patients diagnosed with chronic blepharitis were evaluated for the presence of D. folliculorumby light microscope examination of samples prepared from eyelashes collected by eyelash epilation. Culture samples were also obtained from patients’ eyelid margins. Bacterial strainsamong the predominant bacterial colonies grown in cultures were identified using the BD Phoenix identification system (BD Diagnostic Systems, Sparks, USA). Patients were divided into two groups, Demodex-positive and Demodex-negative,and compared according to bacterial production and bacterial strains produced.&#x0D; Results: D. folliculorumwas identified in 42 (59.1%) patients. Comparison between Demodex-positive and -negative groups revealeda statistically significant increase in Demodex positivity with age.There was no significant relationship between gender and Demodex positivity.The Demodex-positive group showed a statistically significantly higher bacterial growth in the culture samples than the Demodex-negative group.Both groups exhibited a predominance ofStaphylococcus epidermidis. S.epidermidis (38.1% vs. 31.0%), Staphylococcus aureus (19.0% vs. 10.3%), and Corynebacterium spp.(16.7% vs. 6.9%) were detected at higher rates in the Demodex-positive group than in the Demodex-negative group. There was no statistically significant difference between both groups regarding the presence of these bacterial species.&#x0D; Conclusions: Patients with chronic blepharitis could have a mixedinfection site with the combination of D. folliculorumand aerobic bacteria found in the normal eyelid flora.

441. Clinical Characteristics of Pediatric SARS-CoV-2 Infection and Coronavirus Disease 2019 (COVID-19) in Kuwait

BackgroundClinical presentation of coronavirus disease-2019 (COVID-19) ranges from asymptomatic to severe and life threatening. National-level registries found that children, generally, have less severe disease when compared to adults. However, most asymptomatically infected children will not present to hospital and may be missed. We aimed to describe the clinical characteristics in pediatric COVID-19 patients in Kuwait, and to estimate the potential duration of viral shedding.MethodsA retrospective cohort study was performed in Jaber Alahmad Hospital (JAH) from Feb. 29th to Apr. 30th, 2020. During the study period and as part of the public health measures to contain COVID-19, all SARS-CoV-2 infected patients 1 month-18 years old, regardless of symptoms, were hospitalized at JAH, and were included. Demographics, clinical data, and laboratory results were collected. Polymerase chain reaction (PCR) negativity was defined as having two consecutive negative PCR results from a respiratory specimen. Descriptive statistics and multivariable regression analyses were performed.ResultsA total of 134 pediatric SARS-CoV-2 infections were identified. Of those, 91 patients (67.9%) were asymptomatic, the remaining cases had mild COVID-19 illness and mild pneumonia. The median age was 8.8 years (IQR: 4.7–12.4), 55.2% were males, and 89.5% were healthy. Cough and fever were the most commonly reported symptoms. The median duration to PCR negativity was 15 days (IQR: 13–19) for symptomatic patients and 15.5 days (IQR: 14–21) for asymptomatic patients. Predictors for symptoms included abnormal procalcitonin (aOR 6.6; 95% CI 1.48 -29.3), C-reactive protein (aOR 9.10; 95% CI 1.29–32.13), and X-ray finding of pneumonia (aOR 6.44; 95% CI 1.29–32.13).ConclusionAsymptomatic SARS-CoV-2 infection is very common in children. Among symptomatic patients, the disease seems to be mild. Children exhibit substantial duration of viral shedding, as measured by PCR positivity, regardless of symptoms.Disclosures Jesse Papenburg, MD, AbbVie (Consultant, Scientific Research Study Investigator, Research Grant or Support, Speaker’s Bureau)BD Diagnostics (Research Grant or Support)Cepheid (Speaker’s Bureau)MedImmune (Scientific Research Study Investigator)Sanofi Pasteur (Scientific Research Study Investigator)Seegene (Research Grant or Support, Speaker’s Bureau)