Ciprofloxacin Resistance Rates Research Articles

Antimicrobial Resistance Profiles and mupA Gene Characterization of Staphylococcus epidermidis Recovered from Facial Skin of Healthy Females in Shanghai, China.

To explore antimicrobial resistance profiles and mupA gene characterization of Staphylococcus epidermidis recovered from facial skin of healthy females in Shanghai, China. In this study, we collected facial skin samples from 107healthy females in Shanghai, China, and S. epidermidis isolation was performed. The minimal inhibitory concentrations of 10 antibiotics were determined for the S. epidermidis isolates using the agar dilution method. High-level mupirocin-resistant isolates were subjected to whole-genome sequencing and bioinformatics analysis. A total of 94 un-duplicated S. epidermidis isolates were obtained from 107 facial skin samples. Antimicrobial susceptibility tests revealed that 23.4% of the 94 S. epidermidis isolates were resistant to oxacillin and positive for the mecA gene, which could be cauterized as methicillin-resistant S. epidermidis (MRSE). Resistance rates for erythromycin, clindamycin, tetracycline, ciprofloxacin, and gentamicin were 8.5%, 11.7%, 10.6%, 12.8%, and 1.1%, respectively. For mupirocin, the rates of low- and high-level resistance were 3.2% (3/94) and 11.7% (11/94), respectively. Resistance to vancomycin or linezolid was not observed. High-level mupirocin resistance in facial skin isolates is mediated by mupA. WGS and SNP-based phylogenetic analyses revealed diverse phylogenies among the 11 mupA-positive S. epidermidis isolates. Additionally, various resistance and virulence genes were identified in mupA-positive isolates. A new hybrid plasmid carrying mupA genes was found in two S. epidermidis isolates. We observed a considerable level of antimicrobial resistance to several antibiotics and the prevalence of abundant and diverse resistance and virulence genes in the facial skin-origin S. epidermidis isolates. This may pose a potential risk for both public health and S. epidermidis infection.

Genome and antibiotic resistance characteristics of Shigella clinical isolates in Fujian Province, Southeast China, 2005-2019.

Shigellosis is a serious public health issue in many developing countries. The emergence of multidrug-resistant (MDR) Shigella isolates has deepened the treatment difficulty and health burden of shigellosis. China is the largest developing country in the world, but so far, the genome of MDR Shigella isolates has not been well characterized. In this study, 60 clinical isolates of Shigella spp. in Fujian Province, southeast China, from 2005 to 2019 were characterized for drug resistance phenotype, whole-genome sequencing and bioinformatics analysis. The results showed that the MDR rate of Shigella isolates was 100%, among which the resistance rates of cefotaxime, ciprofloxacin and azithromycin were 36.67, 21.67 and 10.00 %, respectively. The positive rate of extended-spectrum beta-lactamase (ESBL)-producing strains was 23.33%. The resistance profiles of Shigella flexneri and Shigella sonnei to some antimicrobials differed. The MDR isolates carried multiple antimicrobial resistance genes, among which blaCTX-M-14 and blaCTX-M-15 mediated ESBL resistance. 'ISEcp1 -blaCTX-M -IS903' (type I) and 'ISEcp1 -blaCTX-M' (type II) were the most common genetic environments around the blaCTX-M genes, and plasmids containing these structures included IncFII, IncI1, IncI2 and IncN. The double gene mutation pattern of gyrA and parC resulted in a significant decrease in the sensitivity of S. flexneri to ciprofloxacin. The overall resistance phenotype and genotype concordance rate was 88.50%, and the sensitivity and specificity of the genotype antimicrobial susceptibility test (AST) were 93.35 and 82.53 %, respectively. However, inconsistency occurred between phenotypic and genotype profiles for a few antibiotics. Phylogenomic investigation with core genome multi-locus sequence typing (cgMLST) and SNPs were used to characterize the endemic transmission of these infections in Fujian and their evolutionary origin within the global context. For S. flexneri, Fujian isolates were all limited to PG3 and could be divided into three phylogenetic clusters. The ciprofloxacin-resistant strains were mainly F2a and FXv and assigned to the three clusters with different quinolone resistance-determining region mutation patterns. For S. sonnei, most Fujian strains belonged to Lineage III with genotype 3.7.6, except three isolates of Lineage I with genotype 1.3. The strains carrying the blaCTX-M genes were dispersed, indicating different origins of gene acquisition. Most of the circulating isolates in Fujian Province were not related to major international outbreak lineages and were only endemic to the country. In conclusion, multi-drug resistance of Shigella isolates in Fujian Province was serious, and genome-based laboratory surveillance will be crucial to the clinical treatment and public health measures for shigellosis.

Antimicrobial Resistance of Environmental V. cholerae Non-O1/O139 Isolates: Systematic Review and Meta-analysis.

The understanding of the antibiotic resistance status of environmental nonO1/nonO139 V. cholerae [NOVC] in relation to other illnesses, which can vary in severity from mild to life-threatening, is limited. However, it is important to note that NOVC-related infections are increasing and serve as a significant illustration of emerging human diseases associated with climate change. The primary objective of the present study was to assess the rates of resistance observed in environmental NOVC isolates across various years, and regions, and their resistance rates. We performed a systematic search of Scopus, PubMed, Web of Science, and EMBASE databases [until May 2024] following PRISMA guidelines. All statistical analyses were carried out using the statistical package R. Our analysis included a total of 34 studies. According to the meta-regression, chlo-ramphenicol, rifampicin, ciprofloxacin, nalidixic acid, cotrimoxazole, kanamycin, trime-thoprim, amoxicillin/clavulanic acid, and tetracycline resistance rate increased over time. The lowest resistance rates were observed in Austria [amoxicillin; 0.6%], the United States [kana-mycin; 0.1% and tetracycline; 0.1%], Morocco [polymyxin B; 12%], and Spain [trimethoprim; 0.3%]. Conversely, the highest resistance rates were found in Spain [amoxicillin; 61%], Indo-nesia [kanamycin and tetracycline; 94.9%], India [polymyxin B; 97.8%], and Morocco [trime-thoprim; 48.9%]. The meta-analysis showed significant variability in antibiotic resistance patterns among environmental NOVC isolates across time and regions, emphasizing the need for tar-geted, time-specific, and country-specific approaches to address antibiotic resistance globally.

Phenotypic and Genotypic Profiles of Extended-Spectrum Beta-Lactamase-Producing Multidrug-Resistant Klebsiella pneumoniae in Northeastern Thailand.

The global emergence of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae presents a significant public health threat and complicates antibiotic treatment for infections. This study aimed to determine the prevalence of ESBL-producing K. pneumoniae in a clinical setting, analyze their antimicrobial susceptibility profiles, and characterize both phenotypic and genetic determinants. A total of 507 non-duplicate clinical isolates of Enterobacterales were collected between 2019 and 2020, and third-generation cephalosporin resistance was screened by disk diffusion. Identification of K. pneumoniae was confirmed using biochemical tests and PCR with species-specific primers. Antimicrobial susceptibility testing was conducted using disk diffusion, and phenotypic ESBL production was confirmed using the combined disk method. Multiplex PCR detected ESBL genes (blaTEM, blaSHV, and blaCTX-M) and identified blaCTX-M groups. The genetic relatedness of ESBL-producing strains was assessed using the ERIC-PCR approach. Fitty-four isolates were confirmed as ESBL producers, all classified as multidrug-resistant (MDR). All ESBL-producing K. pneumoniae isolates exhibited resistance to ampicillin and cefotaxime, with high resistance rates for ciprofloxacin (98.2%), azithromycin (94.4%), piperacillin-tazobactam (88.9%), and trimethoprim (83.3%). Genotypic analysis revealed blaCTX-M was present in 94.4% of isolates, blaSHV in 87%, and blaTEM in 55.5%. The blaCTX-M-1 group was the most prevalent, accounting for 96.1% of isolates. Co-harboring of blaCTX-M, blaSHV, and blaTEM occurred in 42.6% of isolates, with co-carrying of blaCTX-M, and blaSHV was observed in 23/54 isolates. The ERIC-PCR analysis revealed 15 distinct types, indicating high genetic diversity. These findings highlight the urgent need for ongoing monitoring to control the spread of ESBL among K. pneumoniae and emphasize the importance of early detection and appropriate antibiotic selection for effectively treating infection caused by these pathogens.

A molecular and phenotypic analysis of the prevalence and patterns of antimicrobial resistance in Neisseria gonorrhoeae isolates from Kwazulu Natal, South Africa

Antimicrobial drug resistance in Neisseria gonorrhoeae has been documented worldwide; however, the situation in Sub-Saharan Africa has received little attention. It is critical to establish diagnostics and extend surveillance to prevent the emergence of illnesses resistant to multiple treatments. Monitoring antimicrobial susceptibility is crucial to gather data that can inform treatment recommendations, resulting in effective therapy, reduced gonorrhea-related complications and transmission, and efficient treatment. Government authorities may set research and preventive objectives, as well as treatment recommendations, using data from the Gonococcal Antimicrobial Surveillance Program (GISP). Local and state health authorities may use GISP data to make decisions about the allocation of STI prevention services and resources, to guide preventive planning, and to disseminate information about the most successful treatment practices. Using molecular and culture approaches, we investigated the occurrence of antibiotic resistance in isolates from KwaZulu Natal, South Africa. The majority of gonococcal isolates (48 %) showed absolute resistance to ciprofloxacin, with penicillin and tetracycline resistance rates of 14 % each. Only one gonococcal isolate tested positive for azithromycin resistance, with a minimum inhibitory concentration (MIC) of 1.5 µg/mL. Ceftriaxone was effective against all gonococcal isolates tested.

Epidemiological and genetic characterization of multidrug-resistant non-O1 and non-O139 Vibrio cholerae from food in southern China

This study reports a comprehensive epidemiological and genetic analysis of V. cholerae strains, specifically non-O1/non-O139 serogroups, isolated from animal-derived food samples in Guangdong province from 2015 to 2019. A total of 21 V. cholerae strains were obtained, which exhibited high resistance rates for nalidixic acid (57.14 %, 12/21), ampicillin (33.33 %, 7/21), and ciprofloxacin (19.05 %, 4/21). The quinolone resistance-related gene, qnrVC, was prevalent in 80.95 % (17/21) of the isolates. Additionally, chromosomally mediated quinolone-resistance mutations, including mutations in GyrA at position 83 (S83I) and ParC at position 85 (S85L), were detected in 47.62 % of the isolates. The combination of target mutation and qnrVC genes was shown to mediate resistance or intermediate resistance to ciprofloxacin in V. cholerae. Furthermore, an IncC-type conjugative plasmid carrying thirteen antibiotic resistance genes, including genes conferring resistance to two clinically important antibiotics, cephalosporins and fluoroquinolones, was identified in the shrimp-derived strain Vc516. While none of our food isolates harbored the toxigenic CTX- and TCP-encoding genes, they did possess genes encoding toxins such as HlyA and Autoinducer-2. Notably, some V. cholerae strains from this study exhibited a close genetic relationship with clinical strains, suggesting their potential to cause human infections. Taken together, this study provides a comprehensive view of the epidemiological features and genetic basis of antimicrobial resistance and virulence potential of V. cholerae strains isolated from food in southern China, thereby advancing our understanding of this important pathogen.

Prevalence and antimicrobial resistance of bacterial enteropathogens in Crete, Greece, during 2011-2022.

Diarrheal diseases are of great concern worldwide and are responsible for considerable morbidity and mortality. This study investigated the epidemiology and the antibiotic susceptibility of bacterial enteropathogens among diarrheal patients of all ages in Crete, Greece during 2011-2022. Stool specimens were tested by conventional cultural methods for Salmonella, Shigella, Campylobacter, diarrheagenic Escherichia coli (EPEC, STEC), Yersinia enterocolitica, Aeromonas species and Clostridioides difficile. Antimicrobial susceptibility was determined by the disk diffusion method for Enterobacterales, Campylobacter and Aeromonas, and by the gradient diffusion method for C. difficile. Of the 26,060 stool samples from patients of any age, 1,022 (3.9%) were positive for bacterial enteropathogens. Campylobacter spp. were the most commonly isolated bacteria (56.4%), followed by Salmonella enterica (32.3%), and E. coli (EPEC, STEC) (6.5%). Toxigenic C. difficile was isolated from 341 out of 8,848 diarrheal specimens examined (3.9%). Resistance to ampicillin was observed in 12.4% of Salmonella, 66.7% of Shigella and 34.8% of E. coli (EPEC, STEC) isolates. Resistance to trimethoprim/sulfamethoxazole was observed in 5.8% of Salmonella, 33.3% of Shigella, and 15.1% of E. coli (EPEC, STEC) isolates. High rates of ciprofloxacin resistance (77.3%) were detected among Campylobacter isolates, while resistance to erythromycin was observed in 2.4% of them. All C. difficile isolates were susceptible to vancomycin and metronidazole. Our findings suggest declining trends in prevalence of bacterial enteropathogens, except for Campylobacter spp. and changes in the susceptibility rates to antimicrobials. Continuous surveillance of prevalence and antimicrobial susceptibility of bacterial enteropathogens is mandatory for implementing targeted and effective prevention and infection control measures.

Antimicrobial resistance of Salmonella isolates from cattle and horses with salmonellosis in Hokkaido, Japan.

In recent years, reported cases of salmonellosis in cattle and horses in Hokkaido, Japan, have increased. To optimize antimicrobial therapy, we assessed the antimicrobial susceptibility of Salmonella isolates from these animals. Among 112 bovine isolates, high resistance rates were observed for streptomycin (92.0%), ampicillin (88.4%), and tetracycline (79.5%), while resistance rates for kanamycin (8.9%), ciprofloxacin (1.8%), gentamicin (0.0%), and colistin (0.0%) were low. Additionally, 18.8% of the bovine isolates were resistant to cefotaxime, and all of these cefotaxime-resistant isolates carried blaCMY-2. Among 16 equine isolates, no resistance was observed to cefazolin, cefotaxime, gentamicin, nalidixic acid, ciprofloxacin, colistin, or chloramphenicol. Gentamicin and kanamycin are recommended as the first-line treatment for salmonellosis in cattle, with fluoroquinolones as the second choice.

Analysis of blood culture data at a university hospital: bacterial distribution and cumulative antimicrobial resistance (2016–2020)

Background: The distribution of bacteria isolated from bloodstream infections and cumulative antimicrobial susceptibility data are the basis for empirical decisions regarding antibiotics as an initial treatment. Therefore, it is important to consistently collect blood culture results of individual patients and analyze them correctly. Methods: The blood culture results of patients at Gachon University Gil Medical Center from 2016 to 2020 were analyzed retrospectively to determine the bacterial distributions and antibiotic resistance patterns. Duplicates were eliminated by including only the first isolate of each species per patient. Results: Escherichia coli (27.1%) was the most commonly isolated bacterium from blood cultures, followed by Klebsiella pneumoniae (10.1%) and Staphylococcus aureus (8.6%). The methicillin resistance rate of S. aureus was 49.2%, and the vancomycin resistance rate of Enterococcus faecium was 39.5%; with no significant changes over the study period. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of E. coli were 35.0%, 46.8%, and 0.7%, respectively. Seventeen carbapenem-resistant E. coli strains were isolated, of which 11 produced carbapenemase. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of K. pneumoniae were 29.5%, 31.7%, and 5.4%, respectively. Forty-eight carbapenem-resistant K. pneumoniae strains were isolated, of which 37 produced carbapenemase. The imipenem resistance rates of Acinetobacter baumannii and Pseudomonas aeruginosa were 72.3% and 23.4%, respectively. Conclusion: In the blood culture results from 2016 to 2020, the isolation frequency of E. coli, K. pneumoniae, and E. faecium showed an increasing trend, whereas that of S. aureus was stable. Over the 5 year study period, the ciprofloxacin resistance rate of E. coli and P. aeruginosa and ampicillin/sulbactam resistance rate of A. baumannii significantly increased.

Trimethoprim-Sulfamethoxazole and Ciprofloxacin Resistance Rates in Escherichia coli and Klebsiella spp. in Urinary Tract Infections: A 10-Year Evaluation

Objective: Urinary tract infections are the most common bacterial infections among community-acquired infections in all age groups. In this study, we aimed to evaluate the distribution of Escherichia coli and Klebsiella spp. in community-acquired urinary tract infections by years and the resistance rates to trimethoprim-sulfamethoxazole (TMP-SXT) and ciprofloxacin antibiotics, which are used as the first choice in community-acquired urinary tract infections. Methods: All urine culture samples from all age groups admitted to the medical microbiology laboratory from outpatient clinics and emergency services between January 2011 and August 2021 were retrospectively analyzed. Samples with E. coli and Klebsiella spp. detected as causative agents in urine cultures were included in the study. Conventional methods and automated systems were used to identify bacteria and for antibiotic susceptibility tests. Results: E. coli (n=50 430) and Klebsiella spp. (n=7763) isolated from urine cultures between January 2011 and August 2021 were evaluated. The lowest and highest resistance rates for ciprofloxacin and TMP-SXT for E. coli were 25-40% and 35-51%, respectively. Ciprofloxacin and TMP-SXT resistance rates for Klebsiella spp. were the lowest and highest at 17-43% and 31-43%, respectively. Conclusion: Knowing the resistance rates of antibiotics used as the first choice against common agents such as E. coli and Klebsiella spp. in treating community-acquired urinary tract infections may guide the empirical antimicrobial therapy.

The change of antibiotic resistance rates over the years in Enterococcus spp. isolated from clinical specimens

Aims: The aim of this study was to retrospectively evaluate the change in antibiotic resistance rates of Enterococcus species isolated from various clinical samples of outpatients and inpatients in our hospital over the years.
 Methods: Between January 2018 and December 2021, various clinical samples sent to Tekirdağ Namık Kemal University Hospital Microbiology Laboratory from outpatients, inpatients and intensive care patients were retrospectively examined. The samples were inoculated on 5% sheep blood agar, chocolate agar and EMB agar media according to their types and incubated at 37°C. The blood cultures were performed by BACTEC 1280 System (Becton Dickinson, MA, USA). Bacterial identification and antimicrobial sensitivity tests were made using conventional methods and automated systems.
 Results: A total of 417 Enterococcus strains were isolated in our laboratory at four years and included in the study. Of the 417 isolates, 204 (48.9%) were isolated from male patients and 213 (51.1%) from female patients. The mean age of the patients was 57.79±22.9 years (0-96 years). It was determined that 36.9% of the isolates belonged to outpatients, 33.4% to inpatients and 29.7% to intensive care unit patients. Of the 122 enterococci isolates identified as species, 49.2% were typed as Enterococcus faecalis (E. faecalis) and 40.2% as Enterococcus faecium (E. faecium). Of the 417 isolates, 60.4% were isolated from urine samples, 24.2% from blood samples, and 8.9% from wound samples. Considering the total antibiotic resistance rates; ampicillin was 34.9%, ciprofloxacin was 46.4%, vancomycin was 8.4%, tigecline was 3.2%, high-level gentamicin was 49.0%. Linezolid and nitrofurantoin resistance were not detected. Ampicillin and vancomycin resistance rates were determined to have a statistically significant increase within four years. Ampicillin, ciprofloxacin, vancomycin and high-level gentamicin resistance rates were found to be significantly higher in isolates obtained from inpatients and intensive care patients compared to enterococcal isolates obtained from outpatients.
 Conclusion: In our study, it was determined that antibiotic resistance in enterococcal isolates, which are the causative agents of infection in our hospital, increased over the years. In this way, determining the change in antibiotic resistance rates is beneficial in determining appropriate antibiotic use policies. It is thought that conducting surveillance studies on antibiotic resistance periodically and taking new measures according to changing antibiotic resistance rates will be beneficial in terms of treatment.

Clinical features and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen

Objective: To investigate the clinical characteristics, serogroups and antimicrobial resistance of invasive non-typhoid Salmonella infection in children at Xiamen. Methods: Retrospective cohort study. The clinical manifestations, treatment, prognosis, serogroups and antimicrobial resistance of 29 hospitalized children with invasive non-typhoid Salmonella infection confirmed by blood, cerebrospinal fluid, bone marrow and other sterile body fluids or deep pus culture at the Department of Infectious Diseases, the Department of Orthopedics and the Department of General Surgery in Xiamen Children's Hospital from January 2016 to December 2021 were analyzed. According to the clinical diagnosis criteria, the patients were divided into sepsis group and non-sepsis group (bacteremia and local suppurative infection). The inflammatory markers, serogroups distribution and drug resistance were compared between the two groups. Comparison between groups using Mann-Whitney U test and χ2 test. Results: Among the 29 cases, there were 17 males and 12 females, with an onset age of 14 (9, 25) months, and 10 cases (34%) of patients were younger than 1 year old, 15 cases (52%) under 1 to 3 years old, and 4 cases (14%) greater than or equal 3 years old. The onset time of 25 cases (86%) was from April to September. The diseases included 19 cases (66%) septicemia (2 of which were combined with suppurative meningitis), 10 cases (34%) non-sepsis group, including 7 cases bacteremia and 3 cases local suppurative infection (2 cases of osteomyelitis, 1 case of appendicitis with peritonitis). The clinical manifestations were fever in 29 cases (100%), diarrhea and abdominal pain in 18 cases (62%), cough and runny nose in 10 cases (34%). Eighteen cases (62%) were cured and 11 cases (38%) were improved by effective antibiotics treatment. C-reactive protein in sepsis group was significantly higher than that in non-sepsis group (25.2 (16.1, 56.4) vs. 3.4 (0.5, 7.5) mg/L, Z=-3.81, P<0.001).The serogroups of C, B and E were the most prevalent among non-typhoid Salmonella isolates, accounting for 10 cases (34%), 9 cases (31%) and 7 cases (24%) respectively. Antibacterial drug sensitivity test showed that the sensitivity rates of imipenem, ertapenem and piperaciratazobactam were all 100% (31/31), those of ceftazidime, ceftriaxone, and cefepime were 94% (29/31), 94% (29/31) and 97% (30/31) respectively. The drug resistance rates of ampicillin, ampicillin-sulbactam and trimethoprim-sulfamethoxazole were 51% (16/31), 48% (15/31) and 48% (15/31) respectively, those of cefazolin, cefotetan, tobramycin, gentamicin and amikacinwere all 100% (31/31). There were no significant differences in the drug resistance rates of ceftazidime, ceftriaxone, aztreonam, ampicillin-sulbactam, ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin between the sepsis group and the non-sepsis group (χ2=0.31,0.31,0.00,0.02,0.02,0.02,0.26, all P>0.05). Conclusions: Invasive non-typhoid Salmonella infection in children at Xiamen mainly occurred in infants younger than 3 years old.The main clinical manifestations are fever, abdominal pain and diarrhea. C-reactive protein can be served as the laboratory indicators for indicating sepsis. The third generation of cephalosporins is recommended as the first choice for treatment.

Assessment of blood culture and tube agglutination serology test for the diagnosis of typhoid fever amongst malaria-negative patients: a one-year hospital-based study

Salmonella serotypes, including Salmonella Typhi, S. Paratyphi A, S. Paratyphi B, and S. Paratyphi C, are responsible for the systemic, protracted febrile sickness known as typhoid fever. Various antibody-based tests are being used for diagnosing typhoid fever. This study was carried out to assess the performance of the widal test and blood culture for the diagnosis of typhoid fever among malaria-negative patients in a tertiary care hospital in east Delhi, India. The study was conducted from July 2021 to June 2022 in the Department of Microbiology of a tertiary care hospital in Delhi. Patients, including the adult and pediatric population, were evaluated for typhoid fever and participated in an observational, prospective study on febrile patients that was malaria-negative. Venous blood samples were obtained under strict aseptic conditions and further processed for widal serology and blood culture tests for typhoid fever. In our study, the prevalence of blood culture-positive Salmonella species was 0.3% (30/10,000 = 0.3%) Among antimicrobial susceptibility patterns, S. Typhi revealed the highest resistance rates for Ciprofloxacin (43.33%), Azithromycin (36.66%), and third-generation cephalosporins. Out of 30 blood culture-positive Salmonella Typhi of typhoid fever patients, 5 (17%) samples were negative for the Widal test. Among 30 samples, all were blood culture positive, but only 25 samples show Widal titer above the baseline i.e. &gt;1:64. Although blood culture is the gold standard for the diagnosis of typhoid fever, the Widal test does play a role in the diagnosis and management of typhoid fever, especially in suspected cases when blood culture is negative, especially in government tertiary care hospitals.

Investigation of Delafloxacin Resistance in Multidrug-Resistant Escherichia coli Strains and the Detection of E. coli ST43 International High-Risk Clone.

Delafloxacin is a novel fluoroquinolone agent that is approved for clinical application. In this study, we analyzed the antibacterial efficacy of delafloxacin in a collection of 47 Escherichia coli strains. Antimicrobial susceptibility testing was performed by the broth microdilution method and minimum inhibitory concentration (MIC) values were determined for delafloxacin, ciprofloxacin, levofloxacin, moxifloxacin, ceftazidime, cefotaxime, and imipenem. Two multidrug-resistant E. coli strains, which exhibited delafloxacin and ciprofloxacin resistance as well as extended-spectrum beta-lactamase (ESBL) phenotype, were selected for whole-genome sequencing (WGS). In our study, delafloxacin and ciprofloxacin resistance rates were 47% (22/47) and 51% (24/47), respectively. In the strain collection, 46 E. coli were associated with ESBL production. The MIC50 value for delafloxacin was 0.125 mg/L, while all other fluoroquinolones had an MIC50 value of 0.25 mg/L in our collection. Delafloxacin susceptibility was detected in 20 ESBL positive and ciprofloxacin resistant E. coli strains; by contrast, E. coli strains that exhibited a ciprofloxacin MIC value above 1 mg/L were delafloxacin-resistant. WGS analysis on the two selected E. coli strains (920/1 and 951/2) demonstrated that delafloxacin resistance is mediated by multiple chromosomal mutations, namely, five mutations in E. coli 920/1 (gyrA S83L, D87N, parC S80I, E84V, and parE I529L) and four mutations in E. coli 951/2 (gyrA S83L, D87N, parC S80I, and E84V). Both strains carried an ESBL gene, blaCTX-M-1 in E. coli 920/1 and blaCTX-M-15 in E. coli 951/2. Based on multilocus sequence typing, both strains belong to the E. coli sequence type 43 (ST43). In this paper, we report a remarkable high rate (47%) of delafloxacin resistance among multidrug-resistant E. coli as well as the E. coli ST43 international high-risk clone in Hungary.

Australian Gonococcal Surveillance Programme Annual Report, 2022.

The Australian Gonococcal Surveillance Programme (AGSP) has continuously monitored antimicrobial resistance in Neisseria gonorrhoeae for more than 40 years. In 2022, a total of 8,199 isolates from patients in the public and private sectors, in all jurisdictions, were tested for in vitro antimicrobial susceptibility by standardisedmethods. The current treatment recommendation for gonorrhoea, for the majority of Australia, continues to be dual therapy with ceftriaxone and azithromycin. In 2022, of N. gonorrhoeae isolates tested, 0.51% (42/8,199) met the WHO criterion for ceftriaxone decreased susceptibility (DS), defined as a minimum inhibitory concentration value ≥ 0.125mg/L. Resistance to azithromycin was reported in 3.9% of N. gonorrhoeae isolates, proportionally stable since 2019. There were nine isolates with high-level resistance to azithromycin (MIC value ≥ 256 mg/L) reported in Australia: Queensland (4), New South Wales (3), Victoria (1) and non-remote Western Australia (1). This is the highest number detected annually by the AGSP. In 2022, penicillin resistance was found in 38.8% of gonococcal isolates, and ciprofloxacin resistance in 63.3%, however, there was considerable variation by jurisdiction. In some remote settings, penicillin resistance remains low; in these settings, penicillin continues to be recommended as part of an empiric therapy strategy. In 2022, in remote Northern Territory, one penicillin-resistant isolate was reported; in remote Western Australia, 11.8% of gonococcal isolates (9/76) were penicillin resistant. There were three ciprofloxacin-resistant isolates reported from remote Northern Territory; ciprofloxacin resistance rates remain comparatively low in remote Western Australia (6/76;7.9%).

Cost Effectiveness of Rectal Culture-based Antibiotic Prophylaxis in Transrectal Prostate Biopsy: The Results from a Randomized, Nonblinded, Multicenter Trial

BackgroundCulture-based antibiotic prophylaxis is a plausible strategy to reduce infections after transrectal prostate biopsy (PB) related to fluoroquinolone-resistant pathogens. ObjectiveTo assess the cost effectiveness of rectal culture-based prophylaxis compared with empirical ciprofloxacin prophylaxis. Design, setting, and participantsThe study was performed alongside a trial in 11 Dutch hospitals investigating the effectiveness of culture-based prophylaxis in transrectal PB between April 2018 and July 2021 (trial registration number: NCT03228108). InterventionPatients were 1:1 randomized for empirical ciprofloxacin prophylaxis (oral) or culture-based prophylaxis. Costs for both prophylactic strategies were determined for two scenarios: (1) all infectious complications within 7 d after biopsy and (2) culture-proven Gram-negative infections within 30 d after biopsy. Outcome measurements and statistical analysisDifferences in costs and effects (quality-adjusted life-years [QALYs]) were analyzed from a healthcare and societal perspective (including productivity losses, and travel and parking costs) using a bootstrap procedure presenting uncertainty surrounding the incremental cost-effectiveness ratio in a cost-effectiveness plane and acceptability curve. Results and limitationsFor the 7-d follow-up period, culture-based prophylaxis (n = 636) was €51.57 (95% confidence interval [CI] 6.52–96.63) more expensive from a healthcare perspective and €16.95 (95% CI –54.29 to 88.18) from a societal perspective than empirical ciprofloxacin prophylaxis (n = 652). Ciprofloxacin-resistant bacteria were detected in 15.4%. Extrapolating our data, from a healthcare perspective, 40% ciprofloxacin resistance would lead to equal cost for both strategies. Results were similar for the 30-d follow-up period. No significant differences in QALYs were observed. ConclusionsOur results should be interpreted in the context of local ciprofloxacin resistance rates. In our setting, from a healthcare perspective, culture-based prophylaxis was significantly more expensive than empirical ciprofloxacin prophylaxis. From a societal perspective, culture-based prophylaxis was somewhat more cost effective against the threshold value customary for the Netherlands (€80.000). Patient summaryCulture-based prophylaxis in transrectal prostate biopsy was not associated with reduced costs compared with empirical ciprofloxacin prophylaxis.

Antimicrobial resistance profiles of Campylobacter jejuni and Salmonella spp. isolated from enteritis patients in Japan.

Understanding the antimicrobial resistance of Campylobacter jejuni and Salmonella spp. isolated from patients with enteritis will aid in therapeutic decision-making. This study aimed to characterize C. jejuni and Salmonella spp. isolates from patients with enteritis. For C. jejuni, the resistance rates against ampicillin, tetracycline, and ciprofloxacin were 17.2%, 23.8%, and 46.4%, respectively. All the C. jejuni isolates were susceptible to erythromycin, which is recommended as a first-choice antimicrobial if Campylobacter enteritis is strongly suspected. C. jejuni was classified into 64 sequence types (STs), and the five major STs were ST22, ST354, ST21, ST918, and ST50. The ciprofloxacin-resistance rate of ST22 was 85.7%. For Salmonella, the resistance rates against ampicillin, cefotaxime, streptomycin, kanamycin, tetracycline, and nalidixic acid were 14.7%, 2.0%, 57.8%, 10.8%, 16.7%, and 11.8%, respectively. All the Salmonella spp. isolates were susceptible to ciprofloxacin. Therefore, fluoroquinolones are the recommended antimicrobials against Salmonella enteritis. S. Thompson, S. Enteritidis, and S. Schwarzengrund were the three most prevalent serotypes. The two cefotaxime-resistant isolates were serotyped as S. Typhimurium and were found to harbor blaCMY-2. The results of this study would help select antimicrobials for treating patients with Campylobacter and Salmonella enteritis.

The Enterotoxin Production and Antimicrobial Resistance of Campylobacter Strains Originating from Slaughter Animals.

The pathogenicity of animal-origin Campylobacter strains, including antimicrobial resistance and enterotoxigenicity, was determined in this study. Overall, 149 Campylobacter isolates originating from cattle, swine and poultry were tested. The antimicrobial resistance profiles were examined by the diffusion disk method. The dominant resistance pattern was CIP_TET. The resistance rates for ciprofloxacin among swine, cattle and poultry isolates were 84%, 51% and 66%, respectively; for tetracycline, they were 82%, 57.1% and 76%, respectively. None of the obtained isolates was resistant to all four antimicrobials tested. The ability to produce enterotoxins was assessed by the use of a suckling mouse bioassay, with intestinal fluid accumulation as a positive result, and by CHO assay, with the elongation of cells as a positive result. The ability to produce enterotoxins was significantly higher among cattle isolates (61.2% and 71.4% positive isolates, respectively, in the bioassay and the CHO assay) than among swine (16% and 32% positive isolates, respectively) or poultry isolates (14% and 22% positive isolates, respectively). A strong positive correlation between in vitro and in vivo enterotoxicity tests was demonstrated.

Australian Gonococcal Surveillance Programme Annual Report, 2021.

The Australian Gonococcal Surveillance Programme, established in 1981, has continuously monitored antimicrobial resistance in Neisseria gonorrhoeae for more than 40 years. In 2021, a total of 6,254 isolates from patients in the public and private sectors, in all jurisdictions, were tested for in vitro antimicrobial susceptibility by standardised methods. The current treatment recommendation for gonorrhoea, for the majority of Australia, continues to be dual therapy with ceftriaxone and azithromycin. In 2021, of isolates tested, 0.9% were reported nationally with decreased susceptibility (DS) to ceftriaxone (minimum inhibitory concentration [MIC] value ≥ 0.06 mg/L). There was one isolate from non-remote Western Australia that was resistant to ceftriaxone (MIC value ≥ 0.25 mg/L). Resistance to azithromycin (MIC value ≥ 1.0 mg/L) was reported nationally in 4.7% of N. gonorrhoeae isolates. This is increased from that reported in 2020 (3.9%) but similar to the percentage reported in 2019 (4.6%). Isolates with high-level resistance to azithromycin (MIC value ≥ 256 mg/L) are identified sporadically in Australia; none were reported in 2021. In 2021, penicillin resistance was found in 38% of gonococcal isolates nationally, and ciprofloxacin resistance in 53%; however, there is considerable variation by jurisdiction. In some remote settings, penicillin resistance remains low; in these settings, penicillin continues to be recommended as part of an empiric therapy strategy. In 2021, in remote Northern Territory, one penicillin-resistant isolate was reported, and in remote Western Australia 2/83 of gonococcal isolates (2.4 %) were penicillin resistant. There were two ciprofloxacin-resistant isolates reported from remote Northern Territory; ciprofloxacin resistance rates remain comparatively low in remote Western Australia (3/83; 3.6 %).

Evaluation of agents grown from urine culture and antibiotic susceptibility in patients followed up with the diagnosis of urinary system infection

Aim: In this study, it was aimed to determine the reproducing agents and the antibiotic susceptibility of the agents in a total of 89 urine samples cultured in Ankara Training and Research Hospital, Infectious Diseases and Clinical Microbiology laboratory during the 6-month period between 2021-2022. Material and Method: While growth was detected in urine culture in 68 (76%) of 89 urine samples taken in the study, no growth was found in 21 (24%) of them. Antibiotic susceptibility was studied on Mueller-Hinton agar by the disc diffusion method in isolates with growth in urine culture. Results: Reproducing factors are in order of frequency; 25 E. coli, 17 extended-spectrum beta-lactamase (ESBL) positive E. coli, 10 Klebsiella pneumoniae, 3 Pseudomonas aeruginosa, 3 Proteus mirabilis, 3 Enterococcus faecalis, 1 Enterobacter cloacae, 1 Candida krusei, 1 Staphylococcus aureus, 1 patient E. coli and Proteus species were determined. Resistance rates in E. coli strains isolated from urine culture; 20% (4/20) for ciprofloxacin, 5% (1/19) for nitrofurantoin, 9.5% (2/21) for trimethoprim/ sulfamethoxazole (TMP/SMZ). No resistance was found to fosfomycin 0% (0/19) and to carbapenems (imipenem, meropenem, and ertapenem) (0/21). The resistance rates in ESBL positive E. coli strains are; 100% (13/13) for ciprofloxacin, 7% (1/14) for nitrofurantoin, 12.5% (1/8) for fosfomycin, 26.6% (4/15) for TMP-SMZ. No resistance was found to carbapenems (imipenem, meropenem and ertapenem). Conclusion: In our study, it was determined that the most common infectious agent causing urinary tract infection was E. coli. In our study, it was determined that the resistance rates for ciprofloxacin and TMP-SMZ, which are used in empirical treatment, are high, and the resistance rates for fosfomycin and nitrofurantoin are low in E. coli strains that cause urinary system infection. Due to the low rates of resistance in the empirical treatment of urinary system infections, it would be a suitable approach to prefer oral treatment options such as fosfomycin and nitrofurantoin in outpatients.