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Introduction: Antimicrobial susceptibility patterns of bacterial pathogens isolated from patients with complicated urinary tract infections were analyzed using the national surveillance data, comprising 793 bacterial strains from eight clinically relevant species., Materials and Methods: Data were collected for the fourth national surveillance project from July 2020 to December 2021 by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Disease, and the Japanese Society of Clinical Microbiology. Surveillance was supervised with the cooperation of 43 medical institutions throughout Japan., Results: Fluoroquinolone required a minimum inhibitory concentration (MIC) of 2-64 mg/L to inhibit the 330 tested Escherichia coli strains. The proportion of levofloxacin-resistant E. coli strains increased from 28.6% in 2008 to 29.6% in 2011, 38.5% in 2015, and 44.5% in 2021. The proportion of levofloxacin-resistant strains of Pseudomonas aeruginosa also increased from previous survey results, showing a continuing downward trend. Conversely, the proportion of levofloxacin-resistant strains of Enterococcus faecalis decreased relative to previous reports. Neither multidrug-resistant P. aeruginosa nor carbapenem-resistant Enterobacteriaceae were detected. For methicillin-resistant Staphylococcus aureus (MRSA), the proportion of vancomycin-susceptible strains (MIC of 2 μg/mL) decreased from 14.7% to 7.7%., Discussion: Bacterial strains that produced extended-spectrum β-lactamase included E. coli (82/330 strains, 24.8%), Klebsiella pneumoniae (11/68 strains, 16.2%), and Proteus mirabilis (4/26 strains, 15.4%). As compared to previous surveillance reports, these strains showed an increase in proportion over the years., Competing Interests: Declaration of competing interest Satoshi Takahashi received speaker honoraria from Fujirebio Inc. and research funding from Shino-Test Corporation, Roche Diagnostic K. K., Fujirebio Inc., and Abbott Japan Co., Ltd. Koichiro Wada received speaker honoraria from Janssen Pharmaceutical K.K., and MSD K.K. Shingo Yamamoto received speaker honoraria from MSD K.K., Fuso Pharmaceutical Industries, Ltd., Daiichi Sankyo Co., Ltd. and scholarship donations from Takeda Pharmaceutical Co., Ltd., Nippon Shinyaku Co., Ltd., Ono Pharmaceutical Co., Ltd., Bayer Yakuhin, Ltd. and research funding from Takeda Pharmaceutical Co., Ltd. Tetsuya Matsumoto received speaker honoraria from MSD K.K., Pfizer Japan Inc., and Kyorin Pharmaceutical Co., Ltd., and research funding from Kewpie Corporation., Biofermin Pharmaceutical Co., Ltd. Kazumasa Matsumoto received research funding from Sysmex Corporation. Tohru Nakagawa received speaker honoraria from Astellas Pharma Inc., AstraZeneca K.K., Ono Pharmaceutical Co., Ltd., and Janssen Pharmaceutical K.K., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

The Japanese Surveillance Committee conducted a second nationwide surveillance of antimicrobial susceptibility patterns of uropathogens responsible for acute uncomplicated cystitis (AUC) in premenopausal patients aged 16-40 years old at 31 hospitals throughout Japan from March 2015 to February 2016. In this study, the susceptibility of causative bacteria (Escherichia coli, Klebsiella pneumoniae, Staphylococcus saprophyticus) for various antimicrobial agents was investigated by isolation and culturing of organisms obtained from urine samples. In total, 324 strains were isolated from 361 patients, including E. coli (n = 220, 67.9%), S. saprophyticus (n = 36, 11.1%), and K. pneumoniae (n = 7, 2.2%). The minimum inhibitory concentrations (MICs) of 20 antibacterial agents for these strains were determined according to the Clinical and Laboratory Standards Institute (CLSI) manual. At least 93% of the E. coli isolates showed susceptibility to fluoroquinolones and cephalosporins, whereas 100% of the S. saprophyticus isolates showed susceptibility to fluoroquinolones and aminoglycosides. The proportions of fluoroquinolone-resistant and extended-spectrum β-lactamase (ESBL)-producing E. coli strains were 6.4% (13/220) and 4.1% (9/220), respectively. The antimicrobial susceptibility of K. pneumoniae was retained during the surveillance period, while no multidrug-resistant strains were identified. In summary, antimicrobial susceptibility results of our second nationwide surveillance did not differ significantly from those of the first surveillance. Especially the numbers of fluoroquinolone-resistant and ESBL-producing E. coli strains were not increased in premenopausal patients with AUC in Japan., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Flavophospholipol (FPL) is an antimicrobial feed additive that has been approved for use in livestock animals and has the potential to decrease horizontal dissemination of antimicrobial resistance genes. Since previous studies showed that FPL has an inhibitory effect on plasmid transfer, in vitro experiments have proven the efficacy of FPL in reducing the conjugative transfer of plasmids encoding the extended-spectrum β-lactamase (ESBL) and vanA genes. These are among the most important antimicrobial resistance loci known. ESBL-producing Escherichia coli and vancomycin-resistant Enterococcus faecalis (VRE) were exposed to several concentrations of FPL, and transfer frequency and plasmid curing activity were determined. FPL inhibited the conjugative transfer of plasmids harboring ESBL and vanA genes in a concentration-dependent manner in all strains. Further transfer experiments revealed that FPL could decrease or increase transfer frequency depending on plasmid type when transfer frequency was at low levels. The plasmid curing activity of FPL was also observed in ESBL-producing E. coli in a concentration-dependent manner, suggesting that they partially contribute to the inhibition of conjugative transfer. These results suggest that the use of FPL as a feed additive might decrease the dissemination of ESBL and vanA genes among livestock animals.

Genital chlamydial infection is a principal sexually transmitted infection worldwide. Chlamydia trachomatis can cause male urethritis, acute epididymitis, cervicitis, and pelvic inflammatory disease as sexually transmitted infections. Fortunately, homotypic resistant C. trachomatis strains have not been isolated to date; however, several studies have reported the isolation of heterotypic resistant strains from patients. In this surveillance study, clinical urethral discharge specimens were collected from patients with urethritis in 51 hospitals and clinics in 2009 and 38 in 2012. Based on serial cultures, the minimum inhibitory concentration (MIC) could be determined for 19 isolates in 2009 and 39 in 2012. In 2009 and 2012, the MICs (MIC90) of ciprofloxacin, levofloxacin, tosufloxacin, sitafloxacin, doxycycline, minocycline, erythromycin, clarithromycin, and azithromycin were 2 μg/ml and 1 μg/ml, 0.5 μg/ml and 0.5 μg/ml, 0.125 μg/ml and 0.125 μg/ml, 0.063 μg/ml and 0.063 μg/ml, 0.125 μg/ml and 0.125 μg/ml, 0.125 μg/ml and 0.125 μg/ml, 0.016 μg/ml and 0.016 μg/ml, and 0.063 μg/ml and 0.063 μg/ml, respectively. In summary, this surveillance project did not identify any resistant strain against fluoroquinolone, tetracycline, or macrolide agents in Japan., (Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

To investigate antimicrobial susceptibility patterns of various bacterial pathogens isolated from complicated urinary tract infection (UTI) cases, the Japanese Society of Chemotherapy, the Japanese Association of Infectious Disease, and the Japanese Society of Clinical Microbiology conducted the second nationwide surveillance from January to September 2011. With the cooperation of 42 medical institutions throughout Japan, 1036 strains belonging to 8 clinically relevant bacterial species were collected. Among methicillin-resistant Staphylococcus aureus (MRSA) strain, the vancomycin (VCM) MIC for 5.5% (3/55) of the strains was 2 μg/mL. Ampicillin, VCM, and linezolid were relatively active against 209 Enterococcus faecalis strains. The proportion of fluoroquinolone (FQ)-resistant strains was >20%. The MIC90 of FQs against the 382 Escherichia coli strains was 2-64 mg/L and the proportion resistant to FQs was approximately 30%. However, susceptibility of E. coli to sitafloxacin was still high (MIC90 = 2 mg/L). Fifty-eight (15.2%) of 382 E. coli, 6 (4.5%) of 132 Klebsiella pneumoniae, 1 (2.4%) of 41 Klebsiella oxytoca and 4 (6.8%) of 59 Proteus mirabilis strains were suspected of producing extended-spectrum beta-lactamase. Of 93 Pseudomonas aeruginosa strains, the proportions resistant to imipenem, amikacin, and ciprofloxacin were 21.5%, 4.3%, and 20.4%, respectively. Four strains (4.3%) were found to be multidrug-resistant. In complicated UTI cases, all of MRSA and E. faecalis were susceptible to all anti-MRSA agents. Sitafloxacin was active against other FQ-resistant E. coli strains. The isolation of extended-spectrum beta-lactamase-producing and multidrug-resistant strains increased., (Copyright © 2015. Published by Elsevier Ltd.)

Worldwide, the most important concern in the treatment of sexually transmitted infections is the increase in antimicrobial resistant Neisseria gonorrhoeae strains including resistance to cephalosporins, penicillins, fluoroquinolones or macrolides. To investigate the trends of antimicrobial susceptibility among N. gonorrhoeae strains isolated from male patients with urethritis, a Japanese surveillance committee conducted the second nationwide surveillance study. Urethral discharge was collected from male patients with urethritis at 26 medical facilities from March 2012 to January 2013. Of the 151 specimens, 103 N. gonorrhoeae strains were tested for susceptibility to 20 antimicrobial agents. None of the strains was resistant to ceftriaxone, but the minimum inhibitory concentration (MIC) 90% of ceftriaxone increased to 0.125 μg/ml, and 11 (10.7%) strains were considered less susceptible with an MIC of 0.125 μg/ml. There were 11 strains resistant to cefixime, and the MICs of these strains were 0.5 μg/ml. The distributions of the MICs of fluoroquinolones, such as ciprofloxacin, levofloxacin and tosufloxacin, were bimodal. Sitafloxacin, a fluoroquinolone, showed strong activity against all strains, including strains resistant to other three fluoroquinolones, such as ciprofloxacin, levofloxacin and tosufloxacin. The azithromycin MICs in 2 strains were 1 μg/ml., (Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objectives: The increasing prevalence of resistant bacteria such as fluoroquinolone-resistant or extended-spectrum β-lactamase-producing strains in pathogens causing acute uncomplicated cystitis has been of concern in Japan. Faropenem sodium is a penem antimicrobial that demonstrates a wide antimicrobial spectrum against both aerobic and anaerobic bacteria. It is stable against a number of β-lactamases., Methods: We compared 3 and 7 day administration regimens of faropenem in a multicentre, randomized, open-label, controlled study., Results: In total, 200 female patients with cystitis were enrolled and randomized into 3 day (N = 97) or 7 day (N = 103) treatment groups. At the first visit, 161 bacterial strains were isolated from 154 participants, and Escherichia coli accounted for 73.9% (119/161) of bacterial strains. At 5-9 days after the completion of treatment, 73 and 81 patients from the 3 day and 7 day groups, respectively, were evaluated by intention-to-treat analysis; the microbiological efficacies were 58.9% eradication (43/73), 20.5% persistence (15/73) and 8.2% replaced (6/73), and 66.7% eradication (54/81), 6.2% persistence (5/81) and 7.4% replaced (6/81), respectively (P = 0.048). The clinical efficacies were 76.7% (56/73) and 80.2% (65/81), respectively (P = 0.695). Adverse events due to faropenem were reported in 9.5% of participants (19/200), and the most common adverse event was diarrhoea., Conclusions: The 7 day regimen showed a superior rate of microbiological response. E. coli strains were in general susceptible to faropenem, including fluoroquinolone- and cephalosporin-resistant strains., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

To propose an appropriate prophylactic antimicrobial therapy for patients undergoing brachytherapy, we evaluated the relationships between various antimicrobial prophylaxis (AMP) protocols and the incidence of postimplant infections in a multicenter cohort study conducted in Japan. The records of 826 patients with localized prostate cancer who underwent a transperineal (125)I brachytherapy procedure between January 2009 and December 2010 were retrospectively reviewed. Perioperative infections, including surgical site and remote infections, were recorded up to postoperative day 30. A total of 6 (0.73%) patients had a perioperative infection following seed implantation, of whom all received AMP for 1 or more days. None of the patients who received a single-dose protocol of AMP using fluoroquinolone p.o. or penicillin with a beta-lactamase inhibitor i.v. developed a perioperative infection. Statistical analysis showed that a single-dose protocol was more significantly related to a lower risk of perioperative infection as compared to the other AMP protocols examined (p = 0.045). Furthermore, our results indicated that bacteriuria and preoperative hair removal were risk factors of perioperative infection with statistical significance (p = 0.007, p = 0.004). Analysis of patient clinical parameters, including age, American Society of Anesthesiologists score, diabetes mellitus, prostate volume, numbers of implanted seeds and needle punctures, operation time, and indwelling duration time of the Foley catheter, did not reveal significant differences in terms of perioperative infection. Our results indicated that a single-dose AMP protocol is sufficient to prevent perioperative infections following seed implantation. On the other hand, AMP is only one of several measures to prevent perioperative infectious complications. It is necessary to know that the patient must have no bacteriuria and that preoperative hair removal should be avoided.

Neisseria gonorrhoeae is one of the most important pathogens causing sexually transmitted infection, and strains that are resistant to several antimicrobials are increasing. To investigate the trends of antimicrobial susceptibility among N. gonorrhoeae strains isolated from male patients with urethritis, a Japanese surveillance committee conducted the first nationwide surveillance. The urethral discharge was collected from male patients with urethritis at 51 medical facilities from April 2009 to October 2010. Of the 156 specimens, 83 N. gonorrhoeae strains were tested for susceptibility to 18 antimicrobial agents. The prevalence of β-lactamase-producing strains and chromosomally mediated resistant strains were 7.2 % and 16.5 %, respectively. None of the strains was resistant to ceftriaxone, but the minimum inhibitory concentration (MIC) of ceftriaxone for 7 strains (8.4 %) was 0.125 μg/ml. One strain was resistant to cefixime (MIC 0.5 μg/ml). The MICs of fluoroquinolones, such as ciprofloxacin, levofloxacin, and tosufloxacin, showed a bimodal distribution. The MIC of sitafloxacin was lower than those of the three fluoroquinolones listed here, and it was found that the antimicrobial activity of sitafloxacin was stronger than that of the fluoroquinolones. The MIC of azithromycin in 2 strains was 2 μg/ml, but no high-level resistance to macrolides was detected.

The Japanese surveillance committee conducted the first nationwide surveillance of antimicrobial susceptibility patterns of uropathogens responsible for female acute uncomplicated cystitis at 43 hospitals throughout Japan from April 2009 to November 2010. In this study, the causative bacteria (Escherichia coli and Staphylococcus saprophyticus) and their susceptibility to various antimicrobial agents were investigated by isolation and culturing of bacteria from urine samples. In total, 387 strains were isolated from 461 patients, including E. coli (n = 301, 77.8 %), S. saprophyticus (n = 20, 5.2 %), Klebsiella pneumoniae (n = 13, 3.4 %), and Enterococcus faecalis (n = 11, 2.8 %). S. saprophyticus was significantly more common in premenopausal women (P = 0.00095). The minimum inhibitory concentrations of 19 antibacterial agents used for these strains were determined according to the Clinical and Laboratory Standards Institute manual. At least 87 % of E. coli isolates showed susceptibility to fluoroquinolones and cephalosporins, and 100 % of S. saprophyticus isolates showed susceptibility to fluoroquinolones and aminoglycosides. The proportions of fluoroquinolone-resistant E. coli strains and extended-spectrum β-lactamase (ESBL)-producing E. coli strains were 13.3 % and 4.7 %, respectively. It is important to confirm the susceptibility of causative bacteria for optimal antimicrobial therapy, and empiric antimicrobial agents should be selected by considering patient characteristics and other factors. However, the number of isolates of fluoroquinolone-resistant or ESBL-producing strains in gram-negative bacilli may be increasing in patients with urinary tract infections (UTIs) in Japan. Therefore, these data present important information for the proper treatment of UTIs and will serve as a useful reference for future surveillance studies.

Objective: The "Japanese guidelines for prevention of perioperative infections in urological field" was edited by the Japanese Urological Association in 2007. They are the first Japanese guidelines for antimicrobial prophylaxis specifically to prevent perioperative infections in the urological field. We report here the results of a multicenter prospective study conducted to examine the validity and usefulness of these guidelines., Patients and Methods: The subjects were 513 patients who had undergone urological surgeries between July and September 2008 at 10 nationwide university institutions in the Japanese Society of UTI Cooperative Study Group. These surgeries were transurethral resection of bladder (TURBT), transurethral resection of prostate (TURP), adrenalectomy, nephrectomy, nephroureterectomy, radical prostatectomy and total cystectomy. Analysis was performed on patient information, surgical procedures, types and durations of administration of prophylactic antibiotic agents, and the presence of surgical site infections (SSI) and remote infections (RI)., Results: Of 513 patients, 387 (75.4%) were administered prophylactic antibiotic agents according to the guidelines. In these patients, the incidences of SSI and RI were 5.9% and 4.1%, respectively. Multivariate analysis showed that significant factors for SSI were the surgical risk (according to the ASA physical status classification system), diabetes, and operation time, and that the only significant factor for RI was the operation time., Conclusions: More large-scale study and evidences are necessary in order to demonstrate the validity and usefulness of these guidelines.

We investigated whether the presence of menopause influenced the species and distribution of causative bacteria isolated from patients with acute uncomplicated cystitis (the most common urinary tract infection), and we also investigated the sensitivity of the isolated species to antibacterial agents. Using multivariate analysis, we also investigated risk factors for infection with quinolone-resistant Escherichia coli, because its frequency has increased and it is now a clinical problem in Japan. Six hundred and thirty-four strains were isolated from 489 premenopausal patients (mean age 32.3 ± 10.1 years). Major causative bacteria detected were Escherichia coli (65.0 %), Enterococcus faecalis (12.0 %), Streptococcus agalactiae (5.5 %), and Klebsiella pneumoniae (1.6 %). From 501 postmenopausal patients (mean age 68.7 ± 10.29 years), 657 strains were isolated, and the major causative bacteria detected were E. coli (61.5 %), E. faecalis (13.7 %), K. pneumoniae (5.2 %), and S. agalactiae (4.0 %). The sensitivities to fluoroquinolones (FQs) and cephems of E. coli isolated from premenopausal patients were both ≥90 %, while the sensitivities to FQs of E. coli isolated from postmenopausal patients were about 5 % lower. In regard to infection with quinolone-resistant E. coli (minimal inhibitory concentration of levofloxacin [LVFX] ≥4 μg/mL), significant risk factors were observed in patients with more than two episodes of cystitis within a year (p = 0.0002), patients to whom antibacterial agents were used previously for this episode of cystitis (p = 0.0175), and patients who had a history of FQ administration within 1 month. Although the species and distribution of causative bacteria of acute uncomplicated cystitis were the same regardless of the presence of menopause, the sensitivities to FQs of E. coli detected in postmenopausal patients were significantly lower than those in the premenopausal women. The major risk factors for infection with quinolone-resistant E. coli were a history of FQ administration and the morbidity of cystitis rather than the menopausal status. It was considered that taking an appropriate history including the morbidity of cystitis and history of FQ administration, and the appropriate selection of an antibacterial agent, would be important when empirical therapy is required.

Objectives: Coincident with their worldwide use, resistance to fluoroquinolones in Escherichia coli has increased. To identify the gene expression profiles underlying fluoroquinolone resistance, we carried out genome-wide transcriptome analysis of fluoroquinolone-sensitive E. coli., Methods: Four fluoroquinolone-sensitive E. coli and five fluoroquinolone-resistant E. coli clinical isolates were subjected to complementary deoxyribonucleic acid microarray analysis. Some upregulated genes' expression was verified by real-time polymerase chain reaction using 104 E. coli clinical isolates, and minimum inhibitory concentration tests were carried out by using their transformants., Results: A total of 40 genes were significantly upregulated in fluoroquinolone-resistant E. coli isolates (P < 0.05). The expression of phage shock protein operons, which are involved in biofilm formation, was markedly upregulated in our profile of fluoroquinolone-resistant E. coli. One of the phage shock protein operons, pspC, was significantly upregulated in 50 fluoroquinolone-resistant E. coli isolates (P < 0.0001). The expression of type I fimbriae genes, which are pilus operons involved in biofilm formation, were markedly downregulated in fluoroquinolone-resistant E. coli. Deoxyribonucleic acid adenine methyltransferase (dam), which represses type I fimbriae genes, was significantly upregulated in the clinical fluoroquinolone-resistant E. coli isolates (P = 0.007). We established pspC- and dam-expressing E. coli transformants from fluoroquinolone-sensitive E. coli, and the minimum inhibitory concentration tests showed that the transformants acquired fluoroquinolone resistance, suggesting that upregulation of these genes contributes to acquiring fluoroquinolone resistance., Conclusions: Upregulation of psp operones and dam underlying pilus operons downregulation might be associated with fluoroquinolone resistance in E. coli., (© 2011 The Japanese Urological Association.)

In this study, the causative bacteria and their sensitivity to various antimicrobial agents as well as risk factors for quinolone-resistant Escherichia coli were investigated in patients with acute uncomplicated cystitis or complicated cystitis by isolation and culture of bacteria from urine samples. In total, 1312 strains were isolated from 1009 patients with acute uncomplicated cystitis, including E. coli (63.3%), Enterococcus faecalis (12.8%) and Streptococcus agalactiae (4.6%). In addition, 994 strains were isolated from 725 patients with complicated cystitis, including E. coli (36.4%), E. faecalis (19.2%), Klebsiella pneumoniae (5.0%), S. agalactiae (4.7%) and Pseudomonas aeruginosa (4.5%). At least 90% of E. coli isolates from acute uncomplicated cystitis showed sensitivity to fluoroquinolones and cephems, whilst 70.4-88.4% of E. coli isolates from complicated cystitis were sensitive to fluoroquinolones and 85.4-89.5% were sensitive to cephems. Factors associated with quinolone-resistant E. coli included two or more episodes of cystitis within 1 year, failure of quinolone therapy, underlying urinary tract disease, prior quinolone treatment within 1 month and age ≥ 75 years. It is important to confirm the sensitivity of causative bacteria for optimal antimicrobial therapy, and empirical antimicrobial agents should be selected by considering patient characteristics and other factors., (Copyright © 2011. Published by Elsevier B.V.)

Background: The successful treatment of bacterial prostatitis depends on an effective antimicrobial concentration in prostatic tissue against the infecting organism. In this study we compared the diffusion of 5 types of antimicrobials into the prostate., Methods: The concentrations of piperacillin, cefotiam, minocycline, amikacin, and ofloxacin were determined in prostatic fluid, prostatic tissue, and serum 2.5 to 3 hours after a single administration from 55 patients with benign prostatic hypertrophy., Results: Although amikacin showed the highest mean concentration both in prostatic tissue and prostatic fluid, the prostatic tissue/serum ratio was significantly higher (P < 0.01) for ofloxacin (1.49 +/- 0.80) and minocycline (0.94 +/- 0.39) compared with those for amikacin (0.49 +/- 0.21) and piperacillin (0.21 +/- 0.15). Also, the prostatic fluid/serum ratio was lower than the prostatic tissue/serum ratio for each drug, however, the prostatic fluid/serum ratio of ofloxacin was significantly higher than that of other antimicrobials tested (P < 0.01)., Conclusion: These results support earlier studies demonstrating that fluoroquinolones are a useful class of antimicrobials for the treatment of chronic bacterial prostatitis. They also suggest that in view of the pharmacokinetic properties and antimicrobial activities, amikacin and minocycline may be alternate antimicrobial options for selected patients with bacterial infections of the prostate.