Impact of SARS-COV-2 on the diagnosis of community bacteremia in a tertiary hospital

Objective. We carry out an analysis of the bacteremia diagnosed in the Emergency Department during 2020, coinciding with the period of the pandemic. Method. We performed a retrospective analysis from March 4, 2020 to December 31, 2020. Results. The number of patients who went to the Emergency Department during the study period and the number of extracted blood cultures decreased by 46.79% and 35.7% compared to the same period in 2019 (p <0.05). 320 bacteremia occurred while 507 occurred in 2019, assuming a decrease of 36.8% (p <0.05). The positivity rate of blood cultures was 7.09% in 2020 and 7.23% in 2019 and the contamination rate was 7.07 % in 2020 and 5.67% in 2019. The most frequently isolated microorganism was Escherichia coli, followed by Staphylococcus aureus and Klebsiella pneumoniae. A 6.62% of the isolated E. coli were carriers of extended-spectrum beta-lactamases (ESBL). The percentage of methicillin-resistant S. aureus was 12.9 % and that of K. pneumoniae ESBL was 11.54%. Conclusion. During the SARS-CoV-2 pandemic there has been a decrease in the number of bacteremia diagnoses, it is possible that attention was focused especially on COVID, forgetting other diseases, such as bacteremia.

ESBL plasmids in Klebsiella pneumoniae: diversity, transmission, and contribution to infection burden in the hospital setting

Background Resistance to third-generation cephalosporins, often mediated by extended–spectrum beta–lactamases (ESBLs), is a considerable issue in hospital-associated infections as few drugs remain for treatment. ESBL genes are often located on large plasmids that transfer horizontally between strains and species of Enterobacteriaceae and frequently confer resistance to additional drug classes. While plasmid transmission is recognised to occur in the hospital setting, the frequency and impact of plasmid transmission on infection burden, compared to ESBL+ strain transmission, is not well understood. Methods We sequenced the genomes of clinical and carriage isolates of Klebsiella pneumoniae species complex from a year long hospital surveillance study to investigate ESBL burden and plasmid transmission in an Australian hospital. Long term persistence of a key transmitted ESBL+ plasmid was investigated via sequencing of ceftriaxone resistant isolates during four years of follow–up, beginning three years after the initial study. Results We found 25 distinct ESBL plasmids. One (Plasmid A, carrying blaCTX–M–15 in an IncF backbone similar to pKPN–307) was transmitted at least four times into different Klebsiella species/lineages and was responsible for half of all ESBL episodes during the initial one-year study period. Three of the Plasmid A–positive strains persisted locally 3–6 years later, and Plasmid A was detected in two additional strain backgrounds. Overall Plasmid A accounted for 21% of ESBL+ infections in the follow–up period. Conclusions Whilst ESBL plasmid transmission events were rare in this setting, they had a significant and sustained impact on the burden of ceftriaxone resistant and multidrug resistant infections.

KARAKTERISTIK ANTIBIOGRAM ISOLAT Escherichia coli DAN Klebsiella pneumoniae DARI RUANG INTENSIVE CARE UNIT DAN NON-INTENSIVE CARE UNIT DI RSUP SANGLAH SELAMA TAHUN 2018-2020

Resistesi antibiotik meningkat secara global dalam beberapa tahun ini, terutama kejadian Escherichia coli (E.coli) dan Klebsiella pneumoniae (K.pneumoniae) penghasil Extended Spektrum Beta Lactamases (ESBL). Tujuan dari penelitian ini adalah untuk memberikan gambaran prevalensi keberadaan dan antibiogram isolat E.coli dan K. pneumoniae penghasil ESBL di rumah sakit tersier di Bali. Penelitian retrospektif potong lintang ini dlikaukan pada Januari 2018- Desember 2020 di Rumah Sakit Umum Pusat Sanglah, Bali. Identifikasi bakteri dan uji sensitivitas antibiotik dilakukan dengan alat otomatis Vitek®2 Compact. Hasil penelitian menunjukkan dari 2972 isolat, 1067 (63,82%) isolat adalah E. coli penghasil ESBL dan 902 isolat (69,39%) adalah K. pneumoniae penghasil ESBL. Isolat penghasil ESBL ditemukan terbanyak pada non-ICU (89,39%). Bakteri E.coli penghasil ESBL menunjukkan sensitivitas > 80% terhadap Amikacin, Ertapenem, Meropenem, Nitrofurantoin, Piperacillin-tazobactam, dan Tigecycline. Sedangkan, K. pneumoniae penghasil ESBL menunjukkan sensitivitas > 80% terhadap Amikacin, Ertapenem, Meropenem, dan Tigecycline. Penelitian ini menyoroti tingginya prevalensi E.coli dan K.pneumoniae penghasil ESBL di rumah sakit rujukan tersier di Bali. Analisis yang seksama dari antibiogram kedua spesies penghasil ESBL tersebut akan membantu menyusun kebijakan penggunaan antibiotik dan pencegahan, pengendalian penyebaran bakteri penghasil ESBL.Kata Kunci: Escherichia coli; Klebsiella pneumoniae; Extended Spectrum Beta Lactamases; ICU dan Non-ICU

Urinary Tract Infections in Pennsylvania Long-Term Care Facilities

Urinary tract infections (UTIs) are common healthcare-associated infections (HAIs) in older adults that live in long-term care (LTC) facilities. A query of the Pennsylvania Patient Safety Reporting System (PA-PSRS) found that symptomatic UTI (SUTI) and catheter-associated UTI (CAUTI) rates increased from 2016 and peaked in the second quarter of 2020. Although the number of urinary catheter days reported by LTC facilities has trended downward from 2016 to the beginning of 2020, the urinary catheter utilization rate increased slightly in the second quarter of 2020. We also examined various epidemiological factors. An average of 47.6% of SUTIs and 32.3% of CAUTIs were associated with E. coli from 2016 through 2020. However, the percentage of CAUTIs associated with E. coli decreased while the percentage of CAUTIs associated with organisms of the tribe Proteeae (Proteus, Providencia, and Morganella genera) increased from 2016 through 2020. Furthermore, the percentage of CAUTIs associated with carbapenem-resistant Enterobacterales (CRE) and organisms producing extended-spectrum beta-lactamases (ESBL) also increased, while the percentage of CAUTIs associated with vancomycin-resistant Enterococci (VRE) decreased from 2016 through 2020. An average of 38.5% of SUTIs and 41.5% of CAUTIs were reported to be treated with fluoroquinolones from 2016 through 2020. However, the percentage of both SUTIs and CAUTIs treated with fluoroquinolones decreased from 2016 through 2020, while an increasing percentage of both SUTIs and CAUTIs was reported to have been treated with cephalosporins and carbapenems from 2016 through 2020. Thus, to further promote resident safety, we use these epidemiological trends to better understand current risks for residents and to further guide development of best practices for prevention, identification, and treatment of UTIs as well as to further advance antibiotic stewardship practices.

Antibiotic Resistance Pattern and Prevalence of blaOXA-51, blaNDM, blaVIM, blaPER, blaVEB, blaCTX, tetA and tetB Genes in Acinetobacter baumannii Isolated from Clinical Specimens of Hospitals in Tabriz city, Iran

Background: Nowadays, the resistance of pathogenic bacteria to antibiotics has become a global problem. Acinetobacter baumannii is an important opportunistic nosocomial pathogen. Acinetobacter baumannii plays a significant role in antibiotic resistance. Objectives: The purpose of this study was to investigate the prevalence of the blaOXA-51, blaNDM, blaVIM, blaPER, blaVEB, blaCTX-M, tetA and tetB genes and antibiotic resistance pattern of A. baumannii isolated from hospitals in Tabriz city, Iran. Methods: This study was descriptive cross-sectional research, performed on 129 isolates of Acinetobacter from different clinical specimens. The Isolates were identified using standard laboratory methods and culture in selective mediums. The antibiotic resistance pattern of isolates was also determined by the Kirby-Bauer disk diffusion susceptibility test. Phenotypic and genotypic detection of blaOXA-51, blaNDM, blaVIM, blaPER, blaVEB, blaCTX-M, tetA and tetB genes in the isolates was carried out by a combined disk test (CDT) and polymerase chain reaction (PCR), respectively. Results: The highest resistance of isolates was determined to cefotaxime (100%) and ceftazidime (100%). The results of CDT showed that 14 (12.96%) isolates could produce extended-spectrum Beta-lactamases (ESBLs). However, the PCR results blaOXA-51, blaNDM, blaVIM, blaPER, blaVEB, blaCTX-M, tetA and tetB genes showed that these genes were in 100%, 18.51%, 16.66%, 32.40%, 16.66%, 31.48%, 32.40% and 21.29% of isolates, respectively. Conclusions: Due to the high prevalence of antimicrobial resistance in strains, rapid and timely detection of antibiotic-resistant A. baumannii strains is necessary for the selection of an appropriate therapeutic approach and prevention of their prevalence.

Evaluation of Rapid Immunochromatographic Tests for the Direct Detection of Extended Spectrum Beta-Lactamases and Carbapenemases in Enterobacterales Isolated from Positive Blood Cultures

The incidence of bloodstream infections (BSI) with extended spectrum beta-lactamase (ESBL) producing and carbapenemase producing Enterobacterales (CPE) is increasing at an alarming rate, for which only limited therapeutic options remain available. Rapid identification of these bacteria along with their antibiotic resistance mechanisms in positive blood cultures with Gram-negative bacteria will allow for early initiation of effective therapy and limit the overuse of broad-spectrum antibiotics in BSI (1).

Beta-lactam antibiotics and extended spectrum beta-lactamases

Extended spectrum beta-lactamases (ESBLs) are enzymes produced by bacteria, mostly members of the family Enterobacteriaceae commonly Escherichia coli and Klebsiella pneumoniae. ESBLs hydrolyze the beta-lactam ring of beta-lactam antibiotics making these antibiotics ineffective therefore rendering the bacteria resistance against beta-lactam antibiotics. The global upsurge of ESBLs producing bacteria causing both hospital and community acquired infections mostly urinary tract infections, pneumonia and bloodstream infections, threatens the effectiveness of infectious diseases treatment. ESBL families; TEM, SHV and CTX-M are globally disseminated and frequently detected in clinical isolates as well as colonization and contamination isolates. Various laboratory detection methods of ESBLs producing Gram negative bacteria are available. These methods; phenotypic methods, automated methods and molecular-based methods are varying in sensitivity and specificity, need of technical expertise, and rapidness. Therefore, they should be clearly understood before being employed for routine or research use for detection of ESBLs production among Enterobacteriaceae. In addition, understanding the mode of action and mechanisms of resistance to beta-lactam antibiotics, and the epidemiology of ESBLs producing bacteria is of paramount.

1220. Is MIC all that matters? MIC Distributions of Ceftazidime and Cefepime in Ceftriaxone-Resistant E. coli and Klebsiella spp

Background The Clinical and Laboratory Standards Institute (CLSI) lowered MIC breakpoints for many beta-lactam antibiotics to enhance detection of resistance among Enterobacterales. This shift was also meant to eliminate the need for routine testing for extended-spectrum beta-lactamases (ESBLs). The recommended treatment for ESBL-producing Enterobacterales is carbapenems. The IDSA guidelines for MDR-GN organisms recommend using ceftriaxone (CRO) resistance as a proxy for ESBL production and thus carbapenem treatment. Under CLSI guidelines, alternative beta-lactams such as ceftazidime (CAZ) and cefepime (FEP) may still be reported as susceptible and thus used by clinicians even in light of IDSA recommendations. The aim of this project was to characterize the MIC distributions of CAZ and FEP stratified by CRO susceptibility. Methods Clinical E. coli, K. pneumoniae, and K. oxytoca isolates from blood cultures in adult patients from Nov 2016-Dec 2018 that had MICs tested by the Vitek-2 automated susceptibility testing system for CRO, FEP and CAZ were identified. Descriptive statistics were used to compare MIC distributions across the antibiotics of interest (SPSS). Results 573 isolates were included, of these, 17.3% were CRO resistant. Most (53%) CRO-R isolates had FEP MICs ≤2 which is considered susceptible per CLSI; 19% had FEP MICs of 4-8 which would be considered S-DD by CLSI (Figure 1A; breakpoints noted by dashed lines). Using the EUCAST breakpoint of ≤1, only 11% of CRO-R isolates would be reported as FEP-S. For CAZ, 40% of CRO-R isolates had CAZ MICs ≤4, which is considered S by CLSI. Using the EUCAST breakpoint of ≤1, only 12% of CRO-R isolates would be reported as CAZ-S (Figure 1B). Cefepime MIC Distribution for Ceftriaxone Resistant Isolates Distribution of MICs for cefepime for ceftriaxone resistant isolates with the breakpoints for EUCAST and CLSI noted with a dashed line Ceftazidime MIC Distribution for Ceftriaxone Resistant Isolates Distribution of MICs for ceftazidime for ceftriaxone resistant isolates with the breakpoints for EUCAST and CLSI noted with a dashed line Conclusion Half of CRO-R E. coli, K. pneumoniae and K. oxytoca have FEP and CAZ MICs at or below the current CLSI breakpoints. This may lead to their use for serious ESBL infections where a carbapenem is preferred. To prevent unnecessary use, laboratories should consider suppressing FEP and CAZ susceptibilities when CRO-R or adopting more the aggressive EUCAST breakpoints for these agents. Disclosures Emily Heil, PharmD, MS, BCIDP, Nothing to disclose Kimberly C. Claeys, PharmD, GenMark (Speaker’s Bureau)