Phenotypic and genotypic assessment of fluoroquinolones and aminoglycosides resistances in Pseudomonas aeruginosa collected from Minia hospitals, Egypt during COVID-19 pandemic.

BACKGROUND: One of the most prevalent bacteria that cause nosocomial infections is Pseudomonas aeruginosa. Fluoroquinolones (FQ) and aminoglycosides are vital antipseudomonal drugs, but resistance is increasingly prevalent. The study sought to investigate the diverse mechanisms underlying FQ and aminoglycoside resistance in various P. aeruginosa strains particularly during the COVID-19 crisis. METHODS: From various clinical and environmental samples, 110 P. aeruginosa isolates were identified and their susceptibility to several antibiotic classes was evaluated. Molecular techniques were used to track target gene mutations, the presence of genes encoding for quinolone resistance, modifying enzymes for aminoglycosides and resistance methyltransferase (RMT). Efflux pump role was assessed phenotypically and genotypically. Random amplified polymorphic DNA (RAPD) analysis was used to measure clonal diversity. RESULTS: QnrS was the most frequently encountered quinolone resistance gene (37.5%) followed by qnrA (31.2%) and qnrD (25%). Among aminoglycoside resistant isolates, 94.1% harbored modifying enzymes genes, while RMT genes were found in 55.9% of isolates. The aac(6')-Ib and rmtB were the most prevalent genes (79.4% and 32.3%, respectively). Most FQ resistant isolates overexpressed mexA (87.5%). RAPD fingerprinting showed 63.2% polymorphism. CONCLUSIONS: Aminoglycosides and FQ resistance observed in this study was attributed to several mechanisms with the potential for cross-contamination existence so, strict infection control practices are crucial.

Surveillance of fluoroquinolones resistance in rifampicin-susceptible tuberculosis in eastern China with whole-genome sequencing-based approach.

Background: Leveraging well-established DNA-level drug resistance mechanisms, whole-genome sequencing (WGS) has emerged as a valuable methodology for predicting drug resistance. As the most effective second-line anti-tuberculosis (anti-TB) drugs, fluoroquinoloness (FQs) are generally used to treat multidrug-resistant tuberculosis (MDR-TB, defined as being resistant to resistant to rifampicin and isoniazid) or rifampicin-resistant tuberculosis (RR-TB). However, FQs are also commonly used in the management of other bacterial infections. There are few published data on the rates of FQs resistance among rifampicin-susceptible TB. The prevalence of FQs resistance among TB patients who are rifampicin-susceptible has not been studied in Zhejiang Province, China. The goal of this study was to provide a baseline characterization of the prevalence of FQs resistance, particularly among rifampicin-susceptible TB in Zhejiang Province, China. Methods: Based on WGS, we have investigated the prevalence of FQs resistance among rifampicin-susceptible TB in Zhejiang Province. All pulmonary TB patients with positive cultures who were identified in Zhejiang area during TB drug resistance surveillance from 2018 to 2019 have enrolled in this population-based retrospective study. Results: The rate of FQs resistance was 4.6% (32/698) among TB, 4.0% (27/676) among rifampicin-susceptible TB, and 22.7% (5/22) among RR-TB. According to WGS, strains that differ within 12 single-nucleotide polymorphisms (SNPs) were considered to be transmission of FQ-resistant strains. Specifically, 3.7% (1/27) of FQs resistance was caused by the transmission of FQs-resistant strains among the rifampicin-susceptible TB and 40.7% (11/27) of FQs resistance was identified as hetero-resistance. Conclusion: The prevalence of FQs resistance among TB patients who were rifampicin-susceptible was severe in Zhejiang. The emergence of FQs resistance in TB isolates that are rifampicin-susceptible was mainly caused by the selection of drug-resistant strains. In order to prevent the emergence of FQs resistance, the WGS-based surveillance system for TB should be urgently established, and clinical awareness of the responsible use of FQs for respiratory infections should be enhanced.

Intramuscular therapeutic doses of enrofloxacin affect microbial community structure but not the relative abundance of fluoroquinolones resistance genes in swine manure.

Livestock manure is a major source of veterinary antibiotics and antibiotic resistance genes (ARGs). Elucidation of the residual characteristics of ARGs in livestock manure following the administration of veterinary antibiotics is critical to assess their ecotoxicological effects and environmental contamination risks. Here, we investigated the effects of enrofloxacin (ENR), a fluoroquinolone antibiotic commonly used as a therapeutic drug in animal husbandry, on the characteristics of ARGs, mobile genetic elements, and microbial community structure in swine manure following its intramuscular administration for 3 days and a withdrawal period of 10 days. The results revealed the highest concentrations of ENR and ciprofloxacin (CIP) in swine manure at the end of the administration period, ENR concentrations in swine manure in groups L and H were 88.67 ± 45.46 and 219.75 ± 88.05 mg/kg DM, respectively. Approximately 15 fluoroquinolone resistance genes (FRGs) and 48 fluoroquinolone-related multidrug resistance genes (F-MRGs) were detected in swine manure; the relative abundance of the F-MRGs was considerably higher than that of the FRGs. On day 3, the relative abundance of qacA was significantly higher in group H than in group CK, and no significant differences in the relative abundance of other FRGs, F-MRGs, or MGEs were observed between the three groups on day 3 and day 13. The microbial community structure in swine manure was significantly altered on day 3, and the altered community structure was restored on day 13. The FRGs and F-MRGs with the highest relative abundance were qacA and adeF, respectively, and Clostridium and Lactobacillus were the dominant bacterial genera carrying these genes in swine manure. In summary, a single treatment of intramuscular ENR transiently increased antibiotic concentrations and altered the microbial community structure in swine manure; however, this treatment did not significantly affect the abundance of FRGs and F-MRGs.

Transmission of fluoroquinolones resistance among multidrug-resistant tuberculosis in Shanghai, China: a retrospective population-based genomic epidemiology study.

Fluoroquinolones (FQ) are essential for the treatment of multidrug-resistant tuberculosis (MDR-TB). The FQ resistance (FQ-R) rate in MDR-TB in China and its risk factors remain poorly understood. We conducted a retrospective, population-based genomic epidemiology study of MDR-TB patients in Shanghai, China, from 2009 to 2018. A genomic cluster was defined as strains with genetic distances ≤ 12 single nucleotide polymorphisms. The transmitted FQ-R was defined as the same FQ resistance-conferring mutations shared by ≥ 2 strains in a genomic cluster. We used multivariable logistic regression analysis to identify the risk factors for drug resistance. Among the total 850 MDR-TB patients included in the study, 72.8% (619/850) were male, the median age was 39 (interquartile range 28, 55) years, 52.7% (448/850) were migrants, and 34.5% (293/850) were previously treated patients. Most of the MDR-TB strains belong to the Beijing lineage (91.7%, 779/850). Overall, the genotypic resistance rate of FQ was 34.7% (295/850), and 47.1% (139/295) FQ-R patients were in genomic clusters, of which 98 (33.2%, 98/295) were presumed as transmitted FQ-R. Patients with treatment-naïve (aOR = 1.84; 95% CI: 1.09, 3.16), diagnosed in a district-level hospital (aOR = 2.69; 95% CI: 1.56, 4.75), and streptomycin resistance (aOR = 3.69; 95% CI: 1.65, 9.42) were significantly associated with the transmission of FQ-R. In summary, the prevalence of FQ-R among MDR-TB patients was high in Shanghai, and at least one-third were transmitted. Enforced interventions including surveillance of FQ drug susceptibility testing and screening among MDR-TB before initiation of treatment were urgently needed.

Antibiotic susceptibility profiles of Mycoplasma hominis and Ureaplasma urealyticum isolated during a population-based study concerning women infertility in northeast Romania

The study was carried out on 1068 infertile women under initial evaluation. For Mycoplasma hominis, the highest resistance rates were registered for ciprofloxacin (72.22 percent), followed by macrolides and ofloxacin. For Ureaplasma urealyticum, the ciprofloxacin resistance was also high (51.72 percent), while the resistance rates to other tested antibiotics were significantly lower.

Antibiotic susceptibility profiles of Mycoplasma hominis and Ureaplasma urealyticum isolated during a population-based study concerning women infertility in northeast Romania

The study was carried out on 1068 infertile women under initial evaluation. For Mycoplasma hominis, the highest resistance rates were registered for ciprofloxacin (72.22%), followed by macrolides and ofloxacin. For Ureaplasma urealyticum, the ciprofloxacin resistance was also high (51.72%), while the resistance rates to other tested antibiotics were significantly lower.

Resistencia de Neisseria gonorrhoeae a ciprofloxacina según hábitos sexuales / Ciprofloxacin resistance of Neisseria gonorrhoeae according to sexual habits

En la Argentina los primeros hallazgos de Neisseria gonorrhoeae resistentes a las fluorquinolonas se documentaron en el año 2000. Desde enero de 2005 hasta junio de 2007, se evaluaron 595 hombres que tienen sexo con hombres (HSH) y 571 varones heterosexuales para investigar la presencia de N. gonorrhoeae y la resistencia a los antimicrobianos. La prevalencia de gonorrea en HSH y varones heterosexuales fue 0.091(91/1000) en ambos grupos y el % de N. gonorrhoeae resistente a ciprofloxacina (NGRC) fue 20.0% y 3.8% respectivamente (p: 0.0416). Trece de 106 aislamientos fueron NGRC, correspondieron a 11 HSH y 2 varones heterosexuales. Seis HSH presentaron uretritis, uno de ellos con localización simultánea en recto y cinco pacientes fueron asintomáticos (recto, 2; faringe, 2; uretra, 1). No se pudo demostrar relación epidemiológica entre ellos. Dos varones heterosexuales presentaron uretritis. Los 8 pacientes sintomáticos fueron tratados empíricamente con ciprofloxacina y se documentó fracaso de tratamiento. Estos y los portadores de NGRC recibieron tratamiento con 500 mg de ceftriaxona IM. Los controles postratamiento demostraron la erradicación del microorganismo. Los aislamientos de NGRC presentaron CIM de ciprofloxacina entre 2 y 32 µg/ml, todos fueron beta-lactamasa negativos, 4/13 presentaron resistencia cromosómica a penicilina (CIM= 1 µg/ml), y los rangos de CIM (µg/ml) para los siguientes antibióticos fueron: penicilina: 0.016-1; tetraciclina: 0.125-2; ceftriaxona: 0.004-0.008; eritromicina: 0.032-2; azitromicina: 0.032-0.5; espectinomicina: 8-32. Dado el elevado porcentaje de aislamientos de NGRC en HSH en nuestro hospital, debería utilizarse otro antimicrobiano para el tratamiento empírico en estos pacientes.

The first isolates of Neisseria gonorrhoeae resistant to fluorquinolones in Argentina were reported in 2000. Since January 2005 to June 2007 Neisseria gonorrhoeae was studied in 595 men who have sex with men (MSM) and 571 heterosexual men. The gonorrhea prevalence in MSM and heterosexual men was 0.091(91/1000) and the Neisseria gonorrhoeae ciprofloxacin resistant (CRNG) was 20% in MSM and 3.8% in heterosexual men (p: 0.0416). Thirteen out of 106 isolates from 11 MSM and 2 heterosexual men were CRNG. Six out of eleven MSM had urethritis, one also carried Neisseria gonorrhoeae in rectum and 5 patients were asymptomatic carriers (rectum 2, pharynx 2, urethra 1). No epidemiological relation was found among the patients. Two heterosexual men had urethritis. The 8 symptomatic men were treated with ciprofloxacin but treatment failed in all of them. These patients and the asymptomatic ones were treated with ceftriaxone, 500 mg IM. The post treatment microbiological controls were negative. The CRNG isolates had ciprofloxacin MIC between 2 and 32 (µg/ml), all were negative to penicillinase, 4 out of 13 were chromosomally resistant to penicillin (MIC: 1 µg/ml). The MICs (µg/ml) ranges for several antimicrobial agents were: penicillin: 0.016-1; tetracycline: 0.125-2; ceftriaxone: 0.004-0.008; erythromycin: 0.032-2; azithromycin: 0.032-0.5; spectinomycin: 8-32. Due to the high level of ciprofloxacin-resistant N. gonorrhoeae isolated from MSM in our hospital, another antimicrobial agent for empirical therapy should be used in these patients.