Presence of hypervirulence-associated determinants in Klebsiella pneumoniae from hospitalised patients in Germany.

BACKGROUND: Klebsiella (K.) pneumoniae is a ubiquitous Gram-negative bacterium and a common coloniser of animals and humans. Today, K. pneumoniae is one of the most persistent nosocomial pathogens worldwide and poses a severe threat/burden to public health by causing urinary tract infections, pneumonia and bloodstream infections. Infections mainly affect immunocompromised individuals and hospitalised patients. In recent years, a new type of K. pneumoniae has emerged associated with community-acquired infections such as pyogenic liver abscess in otherwise healthy individuals and is therefore termed hypervirulent K. pneumoniae (hvKp). The aim of this study was the characterisation of K. pneumoniae isolates with properties of hypervirulence from Germany. METHODS: A set of 62 potentially hypervirulent K. pneumoniae isolates from human patients was compiled. Inclusion criteria were the presence of at least one determinant that has been previously associated with hypervirulence: (I) clinical manifestation, (II) a positive string test as a marker for hypermucoviscosity, and (III) presence of virulence associated genes rmpA and/or rmpA2 and/or magA. Phenotypic characterisation of the isolates included antimicrobial resistance testing by broth microdilution. Whole genome sequencing (WGS) was performed using Illumina® MiSeq/NextSeq to investigate the genetic repertoire such as multi-locus sequence types (ST), capsule types (K), further virulence associated genes and resistance genes of the collected isolates. For selected isolates long-read sequencing was applied and plasmid sequences with resistance and virulence determinants were compared. RESULTS: WGS analyses confirmed presence of several signature genes for hvKp. Among them, the most prevalent were the siderophore loci iuc and ybt and the capsule regulator genes rmpA and rmpA2. The most dominant ST among the hvKp isolates were ST395 capsule type K2 and ST395 capsule type K5; both have been described previously and were confirmed by our data as multidrug-resistant (MDR) isolates. ST23 capsule type K1 was the second most abundant ST in this study; this ST has been described as commonly associated with hypervirulence. In general, resistance to beta-lactams caused by the production of extended-spectrum beta-lactamases (ESBL) and carbapenemases was observed frequently in our isolates, confirming the threatening rise of MDR-hvKp strains. CONCLUSIONS: Our study results show that K. pneumoniae strains that carry several determinants of hypervirulence are present for many years in Germany. The detection of carbapenemase genes and hypervirulence associated genes on the same plasmid is highly problematic and requires intensified screening and molecular surveillance. However, the non-uniform definition of hvKp complicates their detection. Testing for hypermucoviscosity alone is not specific enough to identify hvKp. Thus, we suggest that the classification of hvKp should be applied to isolates that not only fulfil phenotypical criteria (severe clinical manifestations, hypermucoviscosity) but also (I) the presence of at least two virulence loci e.g. iuc and ybt, and (II) the presence of rmpA and/or rmpA2.

Multicenter Clinical Evaluation of ETEST Eravacycline for Susceptibility Testing of Enterobacteriaceae and Enterococci.

Eravacycline (ERV) (brand name Xerava [Tetraphase]) is a new tetracycline-class antibacterial that has been approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for treatment of complicated intra-abdominal infections (cIAIs). ETEST is a gradient diffusion method that represents a simple alternative to the broth microdilution (BMD) method for performing antimicrobial susceptibility testing (AST). A multicenter evaluation of the performance of the new ETEST ERV (bioMérieux) in comparison with BMD was conducted following FDA and International Standards Organization (ISO) recommendations, using FDA- and EUCAST-defined breakpoints. Clinical isolates of Enterobacteriaceae (n = 542) and Enterococcus spp. (n = 137) were included. Based on the BMD reference method, 92 Enterobacteriaceae isolates and 9 enterococcal isolates were nonsusceptible to ERV according to the FDA breakpoints, while 7 Escherichia coli isolates and 3 Enterococcus sp. isolates were classified as ERV resistant according the EUCAST breakpoints. Referring to FDA performance criteria, the ETEST ERV demonstrated 99.4% and 100.0% essential agreement (EA), 98.0% and 94.9% categorical agreement (CA), very major error (VME) rates of 5.4% and 33.33%, and major error (ME) rates of 1.3% and 3.1% with clinical and challenge isolates, respectively, of Enterobacteriaceae and Enterococcus spp. According to EUCAST breakpoints, E. coli and Enterococcus sp. isolate results also met ISO acceptance criteria for EA and CA (EA of 99.0% and 100.0%, respectively, and CA of 100.0% for both), without any VMEs or MEs. In conclusion, we report that ETEST ERV represents an accurate tool for performing ERV AST of Enterobacteriaceae and Enterococcus sp. isolates.

Multicenter Clinical Evaluation of ETEST Plazomicin (PLZ) for Susceptibility Testing of Enterobacterales.

Plazomicin (PLZ), brand name ZEMDRI (Cipla Therapeutics), is a novel aminoglycoside antibiotic approved by the U.S. Food and Drug Administration (FDA) for treatment of complicated urinary tract infections including pyelonephritis. ETEST® is a gradient diffusion method that represents an alternative to the more laborious broth micro-dilution (BMD) method for performing antimicrobial susceptibility testing (AST). A multi-center evaluation of the performance of the new ETEST PLZ (bioMérieux) was conducted in comparison with BMD following FDA and International Standards Organization (ISO) recommendations using FDA-defined breakpoints. Clinical isolates of Enterobacterales (n = 598) were included. Fifty-three isolates were resistant to PLZ according to BMD. Overall, the ETEST PLZ demonstrated 99.0% essential agreement (EA), 92.8% category agreement (CA), 1.9% very major errors (VME), 0% major errors (ME), and 7.0% minor errors (mE) with both clinical and challenge isolates of Enterobacterales. The VME was found for a single Serratia marcescens strain. Individual species demonstrated EA rates ≥ 90%. In conclusion, we report that ETEST PLZ represents an accurate tool for performing PLZ AST of Enterobacterales.

In vitro activity of gepotidacin against urine isolates of Escherichia coli from outpatient departments in Germany.

BACKGROUND: Escherichia coli is the leading pathogen of community-acquired urinary tract infections. Gepotidacin is a novel, bactericidal, first-in-class triazaacenaphthylene oral antibiotic that inhibits bacterial DNA replication by a distinct mechanism of action that confers activity against most strains of target pathogens, such as E. coli, Staphylococcus saprophyticus and Neisseria gonorrhoeae, including those resistant to other antibiotics. OBJECTIVES: This study assessed the in vitro activity of gepotidacin in comparison with ciprofloxacin and other oral standard-of-care antibiotics using a large collection of urine isolates of E. coli obtained from outpatients in Germany. METHODS: Four hundred and sixty E. coli collected from 23 laboratories during a surveillance study in 2019/2020 were tested. Forty-six isolates (10.0%) produced an ESBL of the CTX-M family, half of which belonged to MDR clonal subgroups of E. coli ST131. Antibiotic susceptibilities were tested at a reference laboratory by broth microdilution according to the standard ISO 20776-1. RESULTS: Fifty-three (11.5%) isolates were ciprofloxacin resistant, 25 (47.2%) of which also produced an ESBL. Overall, MIC50/90 values for gepotidacin were 2/4 mg/L (MIC range 0.125-16 mg/L), with no differences in activity between ciprofloxacin-susceptible and ciprofloxacin-resistant isolates, ESBL-producing and non-ESBL isolates, O25b-ST131 isolates, and isolates susceptible or resistant to fosfomycin, mecillinam or nitrofurantoin. CONCLUSIONS: Gepotidacin showed promising in vitro activity against urine isolates of E. coli, including ciprofloxacin-resistant isolates, ESBL-producing isolates and isolates resistant to oral standard-of-care antibiotics.

Thirty years of VRE in Germany - "expect the unexpected": The view from the National Reference Centre for Staphylococci and Enterococci.

Enterococci are commensals of the intestinal tract of many animals and humans. Of the various known and still unnamed new enterococcal species, only isolates of Enterococcus faecium and Enterococcus faecalis have received increased medical and public health attention. According to textbook knowledge, the majority of infections are caused by E. faecalis. In recent decades, the number of enterococcal infections has increased, with the increase being exclusively associated with a rising number of nosocomial E. faecium infections. This increase has been accompanied by the dissemination of certain hospital-acquired strain variants and an alarming progress in the development of antibiotic resistance namely vancomycin resistance. With this review we focus on a description of the specific situation of vancomycin resistance among clinical E. faecium isolates in Germany over the past 30 years. The present review describes three VRE episodes in Germany, each of which is framed by the beginning and end of the respective decade. The first episode is specified by the first appearance of VRE in 1990 and a country-wide spread of specific vanA-type VRE strains (ST117/CT24) until the late 1990s. The second decade was initially marked by regional clusters and VRE outbreaks in hospitals in South-Western Germany in 2004 and 2005, mainly caused by vanA-type VRE of ST203. Against the background of a certain "basic level" of VRE prevalence throughout Germany, an early shift from the vanA genotype to the vanB genotype in clinical isolates already occurred at the end of the 2000s without much notice. With the beginning of the third decade in 2010, VRE rates in Germany have permanently increased, first in some federal states and soon after country-wide. Besides an increase in VRE prevalence, this decade was marked by a sharp increase in vanB-type resistance and a dominance of a few, novel strain variants like ST192 and later on ST117 (CT71, CT469) and ST80 (CT1065). The largest VRE outbreak, which involved about 2,900 patients and lasted over three years, was caused by a novel and until that time, unknown strain type of ST80/CT1013 (vanB). Across all periods, VRE outbreaks were mainly oligoclonal and strain types varied over space (hospital wards) and time. The spread of VRE strains obviously respects political borders; for instance, both vancomycin-variable enterococci which were highly prevalent in Denmark and ST796 VRE which successfully disseminated in Australia and Switzerland, were still completely absent among German hospital patients, until to date.

In vitro activity of sulbactam/durlobactam against global isolates of carbapenem-resistant Acinetobacter baumannii.

OBJECTIVES: To evaluate the activity of the novel broad-spectrum serine ß-lactamase inhibitor durlobactam (ETX2514) combined with sulbactam against global isolates of carbapenem-resistant Acinetobacter baumannii with defined carbapenem resistance mechanisms compared with reference antimicrobials with known activity against Acinetobacter spp. METHODS: The susceptibility of 246 carbapenem-resistant non-duplicate A. baumannii isolates to sulbactam/durlobactam, amikacin, colistin, imipenem/sulbactam/durlobactam, imipenem, meropenem, minocycline and sulbactam was tested using broth microdilution. Isolates were obtained from various body sites from patients in 37 countries and from six world regions between 2012 and 2016. Identification of carbapenem resistance mechanisms and assignment to A. baumannii clonal lineages was based on WGS. RESULTS: Sulbactam/durlobactam showed excellent activity comparable to colistin but superior to amikacin, minocycline and sulbactam. The sulbactam/durlobactam MIC50/90 values were 1/4 and 2/4 mg/L and the colistin MIC50/90 values were 0.5 and 1 mg/L, respectively. Comparatively, amikacin, minocycline and sulbactam MIC50/90 values were 256/≥512, 2/16 and 16/64 mg/L, respectively. CONCLUSIONS: Sulbactam/durlobactam had excellent in vitro potency against A. baumannii isolates, including those that were resistant to imipenem/meropenem, amikacin, minocycline and colistin, compared with other compounds. Sulbactam/durlobactam has the potential to become a useful addition to the limited armamentarium of drugs that can be used to treat this problem pathogen.

Urinary concentrations and antibacterial activities of nitroxoline at 250 milligrams versus trimethoprim at 200 milligrams against uropathogens in healthy volunteers.

Because of the increasing bacterial resistance of uropathogens against standard antibiotics, such as trimethoprim (TMP), older antimicrobial drugs, such as nitroxoline (NTX), should be reevaluated. This randomized crossover study investigated the urinary concentrations of parent drugs and their metabolites and their antibacterial activities (urinary inhibitory titers [UITs] and urinary bactericidal titers [UBTs]) against uropathogens at three different urinary pH values within 24 h in six healthy volunteers after a single oral dose of NTX at 250 mg versus TMP at 200 mg. In three additional volunteers, urinary bactericidal kinetics (UBK) were studied after oral administration of NTX at 250 mg three times a day. The mean urinary concentrations of NTX and NTX sulfate in 24 h were 0.012 to 0.507 mg/liter and 0.28 to 27.83 mg/liter, respectively. The mean urinary concentrations of TMP were 18.79 to 41.59 mg/liter. The antibacterial activity of NTX was higher in acidic urine than in alkaline urine, and that of TMP was higher in alkaline urine than in acidic urine. The UITs and UBTs of NTX were generally lower than those of TMP except for a TMP-resistant Escherichia coli strain, for which NTX showed higher UITs/UBTs than did TMP. UBK showed mainly bacteriostatic activity of NTX in urine. NTX exhibits mainly bacteriostatic activity and TMP also shows bactericidal activity in urine against susceptible strains. NTX is a more active antibacterial in acidic urine, and TMP is more active in alkaline urine. The cumulative effects of multiple doses or inhibition of bacterial adherence could not be evaluated. (This study has been registered at EudraCT under registration no. 2009-015631-32.).

Antimicrobial susceptibility and molecular epidemiology of Neisseria gonorrhoeae in Germany.

Antimicrobial drug resistance in Neisseria gonorrhoeae has become an increasing public health problem. Hence, surveillance of resistance development is of crucial importance to implement adequate treatment guidelines. Data on the spread of antibiotic resistance among gonococcal isolates in Germany, however, is scarce. In a resistance surveillance study conducted by the Paul Ehrlich Society for Chemotherapy between October 2010 and December 2011, 23 laboratories all over Germany were requested to send N. gonorrhoeae isolates to the study laboratory in Frankfurt am Main. Species verification was performed biochemically using ApiNH and with Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed using the Etest method. For molecular epidemiological analysis, N. gonorrhoeae strains were genotyped by means of N. gonorrhoeae multi-antigen sequence typing. A total of 213 consecutive gonococcal isolates were analyzed in this nationwide study. Applying EUCAST breakpoints, high resistance rates were found for ciprofloxacin (74%) and tetracycline (41%). Penicillin non-susceptibility was detected in 80% of isolates. The rate of azithromycin resistance was 6%, while all strains were susceptible to spectinomycin, cefixime, and ceftriaxone. Molecular typing of gonococcal isolates revealed a great heterogeneity of 99 different sequence types (ST), but ST1407 predominated (n=39). This is the first comprehensive German multi-centre surveillance study on antibiotic susceptibility and molecular epidemiology of N. gonorrhoeae with implications for antibiotic choice for treatment of gonorrhoea. The World Health Organization supports the concept that an efficacious treatment of gonorrhoea results in at least 95% of infections being cured. Accordingly, as spectinomycin is not available on the German market, only the third generation cephalosporins cefixime and ceftriaxone are regarded as valuable drugs for empirical treatment of gonorrhoea in Germany.

Antimicrobial Susceptibility of Bacterial Pathogens from Patients with Ocular Surface Infections in Germany, 2020-2021: A Comparison with the Data from Three Previous National Studies.

Bacteria are a major cause of superficial eye infections, especially in children. The present study aimed to (i) determine the antimicrobial susceptibility patterns of ocular bacterial pathogens recovered in 20 laboratories during the period 2020-2021 and (ii) compare these results to those from three studies of the same design conducted in 2004, 2009, and 2015 in Germany. Cut-off values defined by EUCAST were used as breakpoints. A total of 1366 bacterial isolates were collected. The most frequent ocular specimens were conjunctival smears (54.3%). Susceptibility rates of Staphylococcus aureus (n = 594), Haemophilus influenzae (n = 178), and Streptococcus pneumoniae (n = 149) to chloramphenicol, gentamicin, kanamycin, neomycin, levofloxacin, ofloxacin, and oxytetracycline were >90% each. Overall, only minor changes in resistance levels were observed in the period since 2004. Therefore, all tested antimicrobials can still be recommended for local therapy of ocular surface infections.

In Vitro Activity of Cefiderocol against a Global Collection of Carbapenem-Resistant Acinetobacter baumannii Isolates.

Background: Cefiderocol is a novel siderophore cephalosporin with potent activity against multi-drug-resistant Gram-negative pathogens including carbapenem-resistant Acinetobacter baumannii (CRAB). Methods: The susceptibility of 313 non-duplicate CRAB isolates with defined carbapenem resistance mechanisms from a global collection to cefiderocol, ceftazidime, ceftazidime/avibactam, ceftolozane/tazobactam, ciprofloxacin, colistin, imipenem/relebactam, meropenem, meropenem/vaborbactam, minocycline, and piperacillin/tazobactam was determined using the broth microdilution method. Isolates were obtained from various body sites from patients in 47 countries in five world regions between 2012 and 2016. The identification of carbapenem resistance mechanisms and assignment to A. baumannii international clonal lineages were based on whole genome sequencing. Results: Cefiderocol showed greater activity than comparator antimicrobials of the ß-lactam class, including novel ß-lactams combined with ß-lactamase inhibitors, ciprofloxacin, and minocycline. Cefiderocol MIC50 and MIC90 values were 0.5 mg/L and 4 mg/L, respectively, while colistin had comparable activity with a higher MIC50 at 1 mg/L and a lower MIC90 value of 2 mg/L. Many isolates with elevated cefiderocol MICs ≥ 4 mg/L represented A. baumannii international clone (IC) 1 and harbored a metallo-ß-lactamase. Conclusions: While cefiderocol is a useful addition to the limited armamentarium of drugs targeting this problematic pathogen, a considerable part of CRAB isolates had elevated MIC values in a range of 4 -> 32 mg/L, including all isolates with a metallo-ß-lactamase.

[Therapy of cystitis with nitroxoline-NitroxWin : Prospective, multicenter, non-interventional study and microbiological resistance surveillance]. / Therapie der Zystitis mit Nitroxolin ­ NitroxWin : Prospektive, multizentrische, nicht-interventionelle Studie und mikrobiologische Untersuchungen zur Resistenzsituation.

BACKGROUND: According to German AWMF S3 guideline nitroxoline is recommended as one of the first-choice antibiotics for treatment of acute uncomplicated cystitis (UC) in women. Under real-world conditions the clinical efficacy of nitroxoline should be checked in a noninterventional, prospective and multicenter study (NIS) and the prevalence of nitroxoline resistance in E. coli be monitored. MATERIALS AND METHODS: Female patients with UC treated with nitroxoline (recommended dosage 250 mg tid for 5 days) were included by urologists, general practitioners (GPs), and internists in family medicine throughout Germany from April-December 2022 and followed for 21-28 days. The diagnosis and course of therapy were judged by the Acute Cystitis Symptom Score (ACSS) questionnaire and laboratory investigations (leukocyturia etc). Separately, a nationwide resistance surveillance was performed during 2019-2020 in collaboration with 23 laboratories to collect urinary E. coli isolates and test their susceptibility to nitroxoline. RESULTS: Of the 316 patients with mean (SD) age of 57.2 (±20.4 [median 62.5]) years who were included in the NIS, 193/248 (86.3%) in the per-protocol group and in 193/263 (81.44%) in the intention-to-treat group were clinically successful. Furthermore, 96% of the patients rated the tolerability of nitroxoline as "very good" or "good". All 272 E. coli isolates tested were susceptible to nitroxoline. CONCLUSIONS: Nitroxoline showed very good clinical results in the NIS, and 100% of the tested E. coli urine isolates were susceptible to nitroxoline. Nitroxoline can still be recommended as one of the first-choice antibiotics for treatment of UC in women.

Susceptibility of Multidrug-Resistant Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa from Germany to Ceftolozane-Tazobactam, Ceftazidime-Avibactam, and Imipenem-Relebactam.

This cross-sectional in-vitro resistance surveillance study involving 10 medical laboratories was conducted in 2018. Each study site was asked to collect 30 consecutive nonduplicate isolates per species from hospitalized patients with documented infections. Minimum inhibitory concentrations were determined at a central laboratory. European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints were used for interpretation. A total of 860 isolates were collected, including 298 Escherichia coli, 268 Klebsiella pneumoniae, and 294 Pseudomonas aeruginosa. Fifty (16.8%) E. coli and 63 (23.5%) K. pneumoniae isolates were found to be resistant to third-generation cephalosporins. Resistance to carbapenems (imipenem and/or meropenem) was identified in 5 (1.9%) K. pneumoniae and 64 (21.8%) P. aeruginosa, but not in E. coli. Thirty-three (11.2%) P. aeruginosa isolates were resistant to both carbapenems and 30 (10.2%) P. aeruginosa showed resistance to ≥3 antimicrobials/antimicrobial groups (among piperacillin-tazobactam, ceftazidime, tobramycin, carbapenems, and fluoroquinolones). The susceptibility rates of these multidrug-resistant (MDR) phenotypes to ceftolozane-tazobactam, ceftazidime-avibactam, and imipenem-relebactam were 70-100%, with the exception of carbapenem-resistant K. pneumoniae. Only two K. pneumoniae and four P. aeruginosa isolates were resistant to all three beta-lactam/beta-lactamase-inhibitor combinations. However, this favorable result should be viewed in light of the relatively low prevalence of MDR organisms that require these agents in Germany.

In Vitro Activity of Cefiderocol against Clinical Gram-Negative Isolates Originating from Germany in 2016/17.

Antimicrobial resistance poses a global threat to public health. Of great concern are Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacterales with resistance to carbapenems or third-generation cephalosporins. The aim of the present study was to investigate the in vitro activity of the novel siderophore cephaloporin cefiderocol (CID) and four comparator ß-lactam-ß-lactamase-inhibitor combinations and to give insights into the genetic background of CID-resistant isolates. In total, 301 clinical Enterobacterales and non-fermenting bacterial isolates were selected for this study, including randomly chosen isolates (set I, n = 195) and challenge isolates (set II, n = 106; enriched with ESBL and carbapenemase producers, as well as colistin-resistant isolates). Isolates displayed CID MIC50/90 values of 0.12/0.5 mg/L (set I) and 0.5/1 mg/L (set II). Overall, the CID activity was superior to the comparators against A. baumannii, Stenotrophomonas maltophilia and set II isolates of P. aeruginosa. There were eight CID-resistant isolates detected (MIC > 2 mg/L): A. baumannii (n = 1), E. cloacae complex (n = 5) and P. aeruginosa (n = 2). Sequencing analyses of these isolates detected the acquired ß-lactamase (bla) genes blaNDM-1,blaSHV-12 and naturally occurring blaOXA-396, blaACT-type and blaCMH-3. In conclusion, CID revealed potent activity against clinically relevant organisms of multidrug-resistant Enterobacterales and non-fermenters.

Escherichia coli resistance, treatment patterns and clinical outcomes among females with uUTI in Germany: a retrospective physician-based chart review study.

Real-world data were collected to examine antimicrobial resistance (AMR) prevalence, treatment patterns, and clinical outcomes among female patients with uncomplicated urinary tract infection (uUTI) in Germany. Data were from a retrospective physician-based chart review completed by physicians treating patients with uUTI. Non-pregnant women aged ≥ 12 years, with a uUTI diagnosis, an E. coli-positive urine culture between January 2017-December 2019, and susceptibility test results for ≥ 4 drug classes were eligible. Patients were stratified into three cohorts by drug class susceptibility: susceptible to all (SUS), resistant to one or two drug classes (DR1/2), and resistant to ≥ 3 (MDR) drug classes tested. Among 386 eligible patients [SUS (67.1%); DR1/2 (29.0%); MDR (3.9%)], AMR prevalence was highest for FMIs (18.3%) and lowest for fluoroquinolones (5.2%). The most prescribed drugs were fosfomycin in SUS (44.0%), DR1/2 (41.4%), and fluoroquinolones in MDR (40.0%). Treatment for uUTI failed for 8.8% of patients; failure was more likely in MDR versus SUS [adjusted odds ratio [95% CI] = 4.21 [1.14-1.50]; P = 0.031); incidence of recurrent infection in the 6-months post-index period was higher in DR1/2 versus SUS. These findings may have implications for empiric prescribing, suggesting an unmet need for new treatments.

Glycopeptide resistance in Enterococcus spp. and coagulase-negative staphylococci from hospitalised patients in Germany: occurrence, characteristics and dalbavancin susceptibility.

OBJECTIVES: The aim of this study was to evaluate the occurrence of glycopeptide resistance in enterococci and coagulase-negative staphylococci (CoNS) and to determine the susceptibilities of the identified glycopeptide-resistant isolates to dalbavancin. METHODS: Twenty-two medical laboratories participated in the study conducted in 2016/17 by the Paul-Ehrlich-Society for Chemotherapy. Each laboratory was asked to collect 30 Enterococcus spp. (limited to Enterococcus faecalis and Enterococcus faecium) and 30 CoNS isolates consecutively from hospitalised patients with a proven or suspected infection. RESULTS: A total of 1285 isolates were collected, comprising 364 E. faecalis, 291 E. faecium and 630 CoNS. No E. faecalis isolates (0%) but 76 E. faecium isolates (26.1%) were vancomycin-resistant, of which 21 showed the VanA type and 55 the VanB type. The proportion of vancomycin-resistant strains among E. faecium isolates from patients in intensive care units (21.6%) was significantly lower than that from patients on regular wards (30.5%). Among the CoNS, 67 isolates (10.6%) were teicoplanin-resistant but none were vancomycin-resistant, with resistance only detected in Staphylococcus epidermidis (12.2%), Staphylococcus haemolyticus (17.9%) and Staphylococcus hominis (13.2%). Dalbavancin at ≤0.25 mg/L inhibited all VanB-type enterococci and 95.5% of teicoplanin-resistant CoNS. CONCLUSION: The level of glycopeptide resistance in E. faecalis remains very low in Germany but achieved 26% in E. faecium and was >10% in CoNS. Dalbavancin appears to be a feasible option for treating infections caused by VanB-type vancomycin-resistant E. faecium and teicoplanin-resistant CoNS.

The evolution of carbapenem resistance determinants and major epidemiological lineages among carbapenem-resistant Acinetobacter baumannii isolates in Germany, 2010-2019.

The aim of this study was to investigate and compare the molecular epidemiology and carbapenem resistance determinants in clinical Acinetobacter baumannii isolates collected during four multicentre surveillance studies conducted by the Paul-Ehrlich-Society for Infection Therapy. Isolates were collected prospectively from hospital in-patients at 17 medical centres in Germany over four periods of three- to six-months starting in October of each of 2010, 2013, 2016 and 2019. Species identification was performed by MALDI-TOF, gyrB multiplex polymerase chain reaction (PCR), and detection of the intrinsic blaOXA-51-like gene. Minimum inhibitory concentrations were determined by broth microdilution. The prevalence of carbapenemase-encoding genes was investigated by OXA-multiplex PCR and whole-genome sequencing. Molecular epidemiology was examined by rep-PCR and core-genome multi-locus sequence typing. A total of 302 A. baumannii isolates were collected. Resistance to imipenem and/or meropenem was detected in 58 isolates (19.2%) from 14 centres. The proportion of carbapenem-resistant isolates increased from 21.3% in 2010 to 33.3% in 2013, and then decreased to 13.8% in 2016 and 12.3% in 2019. Forty-six of these isolates were associated with the international clonal lineage IC2 and five with IC1. The most prevalent carbapenemase gene detected was blaOXA-23-like (n=51). Further carbapenem-resistance determinants were blaOXA-40-like (n=1), blaOXA-58-like (n=3) and blaNDM-1 (n=2). In one isolate, ISAba1 was detected upstream of blaOXA-51-like. In conclusion, IC2 was the most prevalent clonal lineage detected in this study. Interestingly, in Germany, carbapenem resistance seems to have decreased in A. baumannii between 2013 and 2019.

Resistance to Mecillinam and Nine Other Antibiotics for Oral Use in Escherichia coli Isolated from Urine Specimens of Primary Care Patients in Germany, 2019/20.

Urinary tract infections (UTIs) are among the most common bacterial infections in humans. Escherichia coli is by far the leading cause of community-acquired UTIs. Pivmecillinam, the oral prodrug of the penicillin derivative mecillinam (amdinocillin), was re-introduced in Germany in March 2016 for first-line treatment of acute uncomplicated cystitis. This study aimed to evaluate the prevalence of resistance to mecillinam in comparison to nine other antibiotics used for oral treatment in E. coli urine isolates after the re-introduction of pivmecillinam. A total of 460 isolates were collected at 23 laboratories of clinical microbiology between October 2019 and March 2020. Forty-six isolates (10.0%) produced an extended-spectrum ß-lactamase (ESBL) of the CTX-M family. Resistance to amoxicillin (43.3%) was most widespread, followed by resistance to trimethoprim-sulfamethoxazole (27.0%), amoxicillin-clavulanic acid (18.0%), cefuroxime (11.3%), and ciprofloxacin (11.1%). Twenty-four E. coli isolates (5.2%) were resistant to mecillinam. The concentrations of mecillinam needed to inhibit 50/90% of the ESBL-producing isolates and the remaining isolates were 1/4 mg/L and 0.5/4 mg/L, respectively. The findings support the recommendation to regard pivmecillinam as a first-line option for the treatment of uncomplicated lower UTIs.

In vitro spectrum of activity of finafloxacin, a novel, pH-activated fluoroquinolone, under standard and acidic conditions.

Finafloxacin is a novel fluoroquinolone that exhibits enhanced antibacterial activity under acidic conditions. The aim of this study was to define the in vitro pH-activity relationship. Finafloxacin exhibited optimal antibacterial activity between pH 5.0 and 6.0 at which MICs were 4- to 8-fold lower than those determined at neutral pH. These observations were then confirmed against a larger collection of bacteria. These data suggest that finafloxacin could potentially offer a therapeutic advantage within acidic foci of infection.