The nationwide study of bacterial pathogens associated with urinary tract infections conducted by the Japanese Society of Chemotherapy

Fourth national Japanese antimicrobial susceptibility pattern surveillance program: Bacterial isolates from patients with complicated urinary tract infections

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.

Endogenous endophthalmitis due to Serratia marcescens secondary to late-onset empyema Post-Cardiac surgery in an End-Stage renal disease patient on peritoneal dialysis

Endogenous bacterial endophthalmitis results from bacterial seeding of the eye during bacteremia. A diagnosis of endogenous bacterial endophthalmitis requires clinical findings such as vitritis or hypopyon along with positive blood cultures. Serratia marcescens is the second most common pathogen causing hospital-acquired ocular infections. This report describes a case of endogenous bacterial endophthalmitis caused by S. marcescens in an older adult with end-stage renal disease (ESRD) on peritoneal dialysis, who had late-onset pleural empyema secondary to coronary artery bypass grafting (CABG). A 61-year-old gentleman presented with a two-day history of cloudy vision, black floaters, pain, swelling, and gradual vision loss in his right eye. There was no history of trauma, ocular surgeries, or previous similar episodes. He had myocardial infarction treated with CABG 3 months back. Examination showed a 3 mm hypopyon in the anterior chamber. He had classic signs of endophthalmitis with positive blood cultures for S. marcescens. He was treated with high-dose intravenous meropenem and intravitreal ceftazidime without vitrectomy. Endophthalmitis progressed to complete vision loss in his right eye, requiring evisceration. Endophthalmitis caused by S. marcescens is rare, but long-term outcomes can be severe, causing complete vision loss in about 60% of the patients. It is usually hospital-acquired, and the source can be late-onset empyema several months after cardiac surgery, in an immunocompromised patient. Systemic antibiotics should be supplemented with intravitreal agents with or without pars plana vitrectomy.

Serratia marcescens Endocarditis

Severe infections due to Serratia marcescens have been documented with increasing frequency in persons who inject drugs and are frequently associated with nosocomial outbreaks. S marcescens endocarditis is rare, and there are very few, if any, reported cases secondary to an infected wound acquired at home. We present such a case in an immunocompetent 50-year-old man with paraplegia for 30 years and chronic decubitus ulcers who likely contracted the rare opportunistic Serratia following sacral wound contact with unclean surfaces in his hotel room bathroom. While it is also possible that the organism was obtained during a hospital admission 2 months before the positive blood cultures, he was found sitting with his ulcer in direct contact with red-pigmented accumulations on the shower floor. Therefore, it is more likely that he acquired the infection outside of the hospital setting. Early and effective management with advanced cardiac techniques and appropriate antibiotic coverage resulted in a positive outcome.

[An analysis of the outbreak situation and background risk factors for drug-resistant urinary tract infection in nursing homes]

AIM

The present study clarified the outbreak situation and background risk factors for drug-resistant bacteria infection in nursing homes.

METHODS

Subjects were 48 elderly individuals with urinary tract infections in 3 nursing homes during the 12-month period from January to December 2020. We analyzed the drug resistance of cultured bacteria using medical records.

RESULTS

Escherichia coli was the most frequently cultured bacteria (37.1%), and extended-spectrum β-lactamase (ESBL) -producing E. coli accounted for 26.1% of specimens. E. coli susceptibility to levofloxacin (LVFX) was seen in 47.8%, resistance in 47.8%, and intermediate response in 4.4%. E. coli susceptibility to ceftriaxone (CTRX) was seen in 73.9%, and resistance in 26.1%. E. coli susceptibility to sulfamethoxazole trimethoprim (ST) mixture was seen 81.8%, while resistance was seen in 18.2%. In addition, among ESBL-producing E. coli, susceptibility to LVFX was seen in 0% and resistance in 83.3%, and an intermediate response was seen in 16.7%, while susceptibility to ST mixture was seen in 83.3% and resistance in 16.7%. No marked differences in background risk factors were seen between the groups with LVFX-resistant and LVFX-susceptible E. coli. However, the body mass index was significantly lower (p=0.0389), and significantly more patients were treated with antimicrobial agents during the 1-year period preceding the sample acquisition and analysis (p=0.0418) in the group with CTRX-resistant E. coli than in the group with CTRX-susceptible E. coli.

CONCLUSION

In the nursing homes examined, LVFX-resistant E. coli were highly prevalent, and ESBL-producing bacteria were also common. When we treat urinary tract infections, refraining from the use of LVFX is desirable, and antimicrobials should be chosen with care.

Molecular Characterization of Enterobacter cloacae Isolated from Urinary Tract Infections

Background: Urinary tract infections represent a major expensive, common public health problem worldwide due to their high prevalence and the difficulties associated with their management. Objectives: This study aimed to characterize the Enterobacter cloacae strains isolated from urinary tract infections in the medical diagnostic laboratories of Shahrekord, Iran. Methods: Urine samples from patients with urinary tract infections from the Shahrekord medical diagnostic laboratories located in Chaharmahal and Bakhtiari Province, Iran, were collected from June 2019 to February 2020. When the samples were cultured, the different isolates of E. cloacae were identified by biochemical tests. Biofilm production capacity was evaluated. Bacterial susceptibility to antibiotics was determined using the Kirby Bauer method, and antibiotic resistance genes were researched by the multiplex PCR technique. Results: In this study, 65 isolates of E. cloacae were obtained. The highest percentage of resistance was observed for co-trimoxazole (84.62%), ampicillin (76.93%), tetracycline (73.85%), and above half of the E. cloacae strain isolates (53,85%) were strongly involved in biofilm production. Some genes, including qnr A, qnr B, qnr S, tetA, tet B, sul1, bla CTXM, bla SHV, and(2)la, ant(3)la, and aac(3)IIa, were detected in the genome of these isolates. Conclusions: The strains are multi-resistant, and their resistance has already reached the carbapenem class. This requires further investigation, and urgent measures must be adopted.

Antimicrobial prescription practices for outpatients with uncomplicated cystitis in Japan

To promote antimicrobial stewardship, we studied antimicrobial prescription rates for uncomplicated cystitis, a common outpatient disease requiring antibiotic treatment. This multicenter retrospective study was performed from January 1, 2018, to December 31, 2020, in Japan, targeting outpatients aged ≥ 20 years whose medical records revealed International Classification of Diseases (ICD-10) codes suggesting uncomplicated cystitis (N300). The data of 1445 patients were collected and that of 902 patients were analyzed. The overall median patient age was 71 years and a proportion of those aged less than 50 years was 18.8% with a female dominance (82.6%). Antimicrobials were prescribed for 884 patients (98.0%) and a total of 623 patients (69.1%) were treated with broad-spectrum drugs, including fluoroquinolones (36.0%), third-generation cephalosporins (29.9%) and faropenem (3.1%). A logistic regression model revealed that the broad-spectrum agents were significantly prescribed for the older patients, male patients, and those who visited internists. Recurrence was observed in 37 (4.1%) cases, and the multivariate analysis suggested any of age, sex, or antimicrobial types were not associated with the recurrence. Collectively, approximately two-thirds of antimicrobials prescribed for uncomplicated cystitis were broad-spectrum agents. The present data would be an indicator for antimicrobial prescriptions in uncomplicated cystitis in Japan.

Classification of the metallo β-lactamase subtype produced by the carbapenem-resistant Pseudomonas aeruginosa isolates in Japan

INTRODUCTION

Multidrug resistant microorganisms are a serious threat to human health. Under the circumstances, a front line of antimicrobials in clinical setting may be carbapenem β-lactams (CRBP). However, emergence of CRBP resistant (CRBP-r) Gram-negative bacteria are the most alarming. CRBP-r is mainly caused to the production of β-lactamase, down and up expression of the diffusion channel and the efflux pump genes, respectively. Among them, production of metallo-β-lactamase (MBL) is a major cause of high-level of CRBP-r.

METHOD

We analyzed the MBL subtypes by PCR and DNA sequencing in CRBP-r Psudomonas aeruginosa in the collection of the joint program by the Japanese Association for Infectious Diseases, Japan Society for Clinical Microbiology and Japanese Society of Chemotherapy (2006-2015 in Japan).

RESULTS

Among 275 strains out of a total 1716 isolates, 23 (8.3%) were MBL-positive exhibiting resistant to meropenem (MEPM), imipenem, ceftazidime, cefepime, ciprofloxacin and levofloxacin without exception and the MIC of MEPM appeared over 128 μg/mL. Their MBL subtype analysis revealed that 16, 2, and 2 isolates were IMP-1, IMP-7 and VIM-2 positive, respectively, and one isolate each expressed either IMP-10, IMP-34 or IMP-41.

CONCLUSIONS

This study revealed that all the MBL-positive CRBP-r isolates were highly resistant to carbapenems dominating IMP-1 production.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Cefaclor as a first-line treatment for acute uncomplicated cystitis: a retrospective single-center study

Background

Wide-spectrum antibiotics have been favored to treat acute uncomplicated cystitis (AUC) for a long time, leading to the emergence of multi-drug resistant bacteria. We hypothesize that narrow-spectrum antibiotics might mitigate the issue and aim to investigate the clinical efficacy of cefaclor in patients with AUC.

Methods

We retrospectively reviewed the clinical data of female outpatients with AUC treated with cefaclor and evaluated the safety and clinical efficacy. Clinical cure was defined as the elimination of clinical symptom under 4 white blood cells (WBCs) per high power field on microscopy.

Results

Overall, 223 women with AUC were enrolled. Escherichia coli was the dominant pathogen (n = 160; 68.6%), followed by Klebsiella species and E. coli-extended spectrum β-lactamase (ESBL) (n = 19; 8.1% and n = 18; 7.7%). Overall success rate was 94.0% (n = 219) and susceptibility rate of cefazolin was 84.1%, which was close to that of levofloxacin (82.9%). Ampicillin showed the lowest rate of 63.7% with a significantly greater resistance rate of 35.3% among all antibiotics (P < 0.001). In the subgroup analysis, the success rate in patients with resistance to levofloxacin or cefazolin was 100% (n = 24) or 93.3% (n = 14). The rate in patients with resistance to both antibiotics was 60.0% (n = 9), and the pathogens in the other 40.0% (n = 6) of patients with treatment failure were E. coli-ESBL.

Conclusion

Cefaclor showed excellent efficacy in AUC patients, even in those with in vitro resistance to cefazolin or levofloxacin. Cefaclor may be considered as a first-line option in patients with AUC and a second-line option for those with levofloxacin treatment failure.

The third national Japanese antimicrobial susceptibility pattern surveillance program: Bacterial isolates from complicated urinary tract infection patients

The antimicrobial susceptibility patterns of bacterial pathogens isolated from patients with complicated urinary tract infections were analyzed using national surveillance data. The data consisted of 881 bacterial strains from eight clinically relevant species. The data were collected for the third national surveillance project from January 2015 to March 2016 by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Disease, and the Japanese Society of Clinical Microbiology. Surveillance was undertaken with the cooperation of 41 medical institutions throughout Japan. Fluoroquinolone required a MIC₉₀ of 2-64 mg/L to inhibit the 325 Escherichia coli strains tested and the proportion of levofloxacin resistant E. coli strains increased to 38.5% from 29.6% in 2011 and 28.6% in 2008. The proportion of levofloxacin resistant strains of Pseudomonas aeruginosa and Enterococcus faecalis decreased from previous reports and the proportion of multidrug-resistant P. aeruginosa and carbapenem-resistant Enterobacteriaceae remained low. Among methicillin-resistant Staphylococcus aureus (MRSA) strains, strains with reduced susceptibility to vancomycin (minimum inhibitory concentration, 2 μg/mL) increased to 14.7% from 5.5%. Bacterial strains that produced extended-spectrum β-lactamase included E. coli (79 of 325 strains, 24.3%), Klebsiella pneumoniae (9 of 177 strains, 7.7%), and Proteus mirabilis (6 of 55 strains, 10.9%). The proportion of extended-spectrum β-lactamase producing E. coli and K. pneumoniae strains increased from previous surveillance reports.

Clinical outcomes of urinary tract infection caused by extended spectrum beta-lactamase producing Enterobacteriaceae: a retrospective observational study comparing patients with and without systemic inflammatory response syndrome

Aim

In severe urinary tract infection (UTI), susceptible antibiotics should be given. With the recent increase of multidrug‐resistant bacteria, especially extended spectrum beta‐lactamase producing Enterobacteriaceae (ESBL‐E), broad‐spectrum antibiotics, such as carbapenems, are used more frequently, which could lead to a further increase of multidrug‐resistant bacteria. We aimed to analyze the relationship between initial empirical antibiotic appropriateness and clinical outcomes in UTI, especially in patients with systemic inflammatory response syndrome (SIRS) and ESBL‐E.

Methods

A retrospective observational study from 2012 to 2017.

Results

Among urine culture‐positive cases with ≥10⁵ colony‐forming units/mL (n = 1,880), true UTI cases were extracted (n = 844) and divided into the SIRS group (n = 336 [ESBL‐E12.8% (43/336)]) and non‐SIRS group (n = 508 [ESBL‐E12.6% (64/508)]). In the SIRS ESBL‐E group, the initial antibiotics were susceptible in 55.8% (24/43), among which 91.7% (22/24) improved and 8.3% (2/24) deteriorated or died. The initial antibiotics were resistant in 44.2% (19/43), among which 47.4% (9/19) improved with the initial antibiotics, 47.4% (9/19) improved after escalating antibiotics, and 5.3% (1/19) deteriorated or died. In the SIRS group, 14 cases had true bacteremia with ESBL‐E. Seven cases were initiated with inappropriate antibiotics; four cases showed improvement before or without antibiotic change and three cases improved after antibiotic escalation.

Conclusion

Initiation of narrow‐spectrum antibiotics in septic UTI with ESBL‐E might not deteriorate the clinical outcome if promptly escalated on clinical deterioration or with ESBL‐E culture results. Further investigation is warranted to guide judicious use of initial antibiotics.

Comparison between local and national epidemiology of antimicrobial resistance using the JANIS data

The Japanese Ministry of Health, Labor and Welfare established the Japanese Nosocomial Infection Surveillance (JANIS) system in July 2000 to provide nationwide epidemiological information. The data of all clinically isolated bacteria at participating hospitals were collected, treated according to a protocol, and analyzed by the JANIS office. Nationwide and individual hospital data were reported to participating hospitals monthly and yearly. In this study, we surveyed local antimicrobial resistance of clinically isolated bacteria in Kawasaki City between 2014 and 2016 using JANIS data. There were 8, 14, and 16 major hospitals in Kawasaki City that participated in the surveillance in 2014, 2015, and 2016, respectively. The data were returned to each hospital monthly from JANIS, totaled for Kawasaki City, and compared with the nationwide data. The Kawasaki City data were approximately the same as the nationwide data, and most resistant bacteria decreased gradually over the three years examined. The incidence of methicillin-resistant Staphylococcus aureus (MRSA) in S. aureus (Kawasaki City, Japan) was (56.6%, 48.8%), (50.5%, 47.9%), and (51.6%, 46.9%), the incidence of penicillin-resistant Streptococcus pneumoniae (PRSP) in S. pneumoniae, was (43.4%, 37.5%), (34.3%, 38.0%), and (31.4%, 36.9%) in 2014, 2015, and 2016, respectively. Therefore, in Kawasaki City the incidence of MRSA was relatively higher and that of PRSP was relatively lower than the nationwide incidences. Both continuous local and national surveillance are important for monitoring antimicrobial resistance in clinical isolates. The JANIS database is a powerful tool for the epidemiology of nosocomial infections in Japanese hospitals.

Characterization of antimicrobial resistance and quinolone resistance factors in high-level ciprofloxacin-resistant Enterococcus faecalis and Enterococcus faecium isolates obtained from fresh produce and fecal samples of patients

BACKGROUND

The emergence of fluoroquinolone-resistant enterococci is worldwide. Antimicrobial resistance was characterized and the effect of quinolone-resistance factors was analyzed in high-level ciprofloxacin-resistant (HLCR) Enterococcus faecalis and Enterococcus faecium isolated from fresh produce and fecal samples of patients.

RESULTS

Among the 81 ciprofloxacin-resistant Enterococcus isolates, 46 showed high levels of ciprofloxacin resistance, resistance to other quinolone antibiotics, and multidrug resistance profiles. The virulence factors esp and hyl were identified in 27 (58.7%) and 25 (54.3%) of isolates, respectively. Sequence type analysis showed that 35 strains of HLCR E. faecium were clonal complex 17. Eleven strains of HLCR E. faecalis were confirmed as sequence type (ST) 28, ST 64 and ST 125. Quinolone resistance-determining region mutation was identified in HLCR Enterococcus isolates; with serine being changed in gyrA83, gyrA87 and parC80. This result shows that gyrA and parC mutations could be important factors for high-level resistance to fluoroquinolones.

CONCLUSION

No significant differences were observed in antimicrobial resistance patterns and genetic characteristics among the isolates from fresh produce and fecal samples. Therefore, good agricultural practices in farming and continuous monitoring of patients, food and the environment for Enterococcus spp. should be performed to prevent antimicrobial resistance and enable reduction of resistance rates. © 2016 Society of Chemical Industry.

Efficacy and safety of 3 day versus 7 day cefditoren pivoxil regimens for acute uncomplicated cystitis: multicentre, randomized, open-label trial

BACKGROUND

Fluoroquinolone-non-susceptible Escherichia coli isolated from patients with acute uncomplicated cystitis are a matter of increasing concern. Cefditoren pivoxil is an oral, β-lactamase-stable, extended-spectrum cephalosporin that is effective against fluoroquinolone-non-susceptible bacteria.

OBJECTIVES

To evaluate the clinical and microbiological efficacies of cefditoren pivoxil against acute uncomplicated cystitis and to determine the optimal duration of cefditoren pivoxil treatment.

METHODS

We compared 3 and 7 day regimens of cefditoren pivoxil in a multicentre, randomized, open-label study.

RESULTS

A total of 104 female patients with acute uncomplicated cystitis were enrolled and randomized into 3 day (n = 51) or 7 day (n = 53) treatment groups. At first visit, 94 bacterial strains were isolated from the 104 participants of which 81.7% (85/104) were E. coli. Clinical and microbiological efficacies were evaluated 5-9 days following administration of the final dose of cefditoren pivoxil. The clinical efficacies of the 3 and 7 day groups were 90.9% (40/44) and 93.2% (41/44), respectively (P = 1.000). The microbiological efficacies of the 3 and 7 day groups were 82.5% (33/40) and 90.2% (37/41), respectively (P = 0.349). There were no adverse events due to cefditoren pivoxil treatment, with the exception of a mild allergic reaction in one patient, after which the cefditoren pivoxil was exchanged for another antimicrobial.

CONCLUSIONS

Cefditoren pivoxil is safe and effective for uncomplicated cystitis, with no significant differences in clinical and microbiological efficacies between 3 and 7 day regimens.

Marvelous but Morbid: Infective endocarditis due to Serratia marcescens

A 46-year-old man with HIV infection and active intravenous drug use presented with approximately two weeks of fevers and body aches. On physical examination he was somnolent, had a new systolic murmur, bilateral conjunctival hemorrhages, diffuse petechiae, and left-sided arm weakness. Echocardiography revealed a large mitral valve vegetation and brain imaging demonstrated numerous embolic infarctions. Blood cultures grew Serratia marcescens. Despite aggressive treatment with meropenem the patient died due to intracranial hemorrhage complicated by herniation. Serratia marcescens is an uncommon cause of infective endocarditis. While this disease has historically been associated with intravenous drug use, more recent reports suggest that it is now largely a consequence of opportunistic infections of the chronically ill. Our case highlights several characteristic features of this infection, including isolation of a non-pigmented strain of the organism, an antibiotic susceptibility profile suggestive of AmpC β-lactamase production, and rapid clinical deterioration with multiple embolic complications resulting in death. In this review we discuss the history, epidemiology, and management of endovascular infections due to Serratia spp., emphasizing the continued importance of considering this organism in the differential diagnosis of endocarditis among intravenous drug users and as a potential indication for surgical therapy.

Serratia marcescens osteomyelitis in Cushing's disease

We report a case of a 46-year-old man with fever, hypotension and arthralgias of the ankles and knees after brain surgery for a pituitary tumour causing Cushing's disease. Blood and urine cultures isolated Serratia marcescens; antibiotic susceptibility testing showed sensitivity to piperacillin-tazobactan and ciprofloxacin. Articular MRI showed inflammation and necrosis of both knees and ankles, and left hip and right elbow (compatible with osteomyelitis). Culture of an ankle abscess on the ankle joint was positive for Serratia marcescens. Bone scintigraphy confirmed osteomyelitic lesions. Medical treatment included antibiotics and strong opioid therapy for 14 weeks. The patient was discharged clinically improved maintaining ciprofloxacin for 24 additional weeks based on clinical and analytic recovery.

Efficacy of two-time prophylactic intravenous administration of tazobactam/piperacillin for transrectal ultrasound-guided needle biopsy of the prostate

BACKGROUND

Prevalence of fluoroquinolone (FQ)-resistant Escherichia coli has been recently increasing worldwide. We analyzed the incidence and characteristics of acute bacterial prostatitis after transrectal ultrasound-guided needle prostate biopsy (TRUSP-Bx) with prophylactic tazobactam/piperacillin (TAZ/PIPC) treatment as an alternative regimen.

METHODS

A total of 391 patients who underwent TRUSP-Bx were included in the study. All patients received intravenous TAZ/PIPC (4.5 g) 30 minutes before and 6 hours after TRUSP-Bx.

RESULTS

Acute bacterial prostatitis developed in six patients (1.5%); the frequency of its occurrence was significantly higher in patients in whom rectal disinfection was not performed (P < 0.05). These six patients developed clinical symptoms of acute bacterial prostatitis a median of 24 hours after the biopsy. Escherichia coli was isolated in urine or blood bacterial cultures in four cases, and Klebsiella pneumoniae in two cases. All of the isolated organisms showed excellent sensitivity to TAZ/PIPC.

CONCLUSIONS

The incidence rate of acute prostatitis with prophylactic TAZ/PIPC was consistent with those reported previously with FQ-based regimens, despite the favorable sensitivity of isolated organisms. Two-time regimen of TAZ/PIPC may not always prevent the post-TRUSP-Bx infection, possibly due to the pharmacokinetic characteristics of TAZ/PIPC. However, if each case was considered individually to select the best setting and frequency of dosage of TAZ/PIPC, this can be an optimal prophylaxis in the era of widespread FQ-resistant microorganisms.

Molecular epidemiological characterization of uropathogenic escherichia coli from an outpatient urology clinic in rural Japan

In the remote Japanese community of Saku, a rural town in the Nagano Prefecture, a large proportion of outpatient urinary tract infections was caused by well-recognized globally dispersed clonal lineages of uropathogenic Escherichia coli (UPEC). However, most of these strains were drug susceptible, suggesting that factors other than selection pressure account for the clonal spread of drug-susceptible UPEC.

[Mortality predictive factors in patients with urinary sepsis associated to upper urinary tract calculi]

PURPOSE

The aims of this study were to determine the clinical characteristics of patients with urinary sepsis associated to ureteral calculi admitted to the Intensive Care Unit (ICU), and to identify predictors of mortality in the first 24 hours of admission.

DESIGN

A retrospective observational study covering a 16-year period (2006-2011) was carried out.

SETTING

The combined clinical/surgical ICU of a secondary-level University hospital.

PATIENTS

All patients admitted to the ICU due to obstructive urinary sepsis.

INTERVENTIONS

None.

MAIN VARIABLES

We analyzed general clinical and laboratory test and urological data. The diagnostic technique, affected side, decompression technique, isolated microorganism and antibiotic therapy used were also considered. The assessment of risk factors was performed by multiple logistic regression analysis.

RESULTS

A total of 107 patients admitted to the ICU were included in the study, with a mortality rate of 19.6%. The diagnosis was mainly established by ultrasound, and the most commonly used decompression technique was retrograde JJ stenting. Microorganisms were isolated in 48.6% of the patients. In total, 20.6% of the patients had bacteremia. Multivariate analysis found age, acute renal failure and the use of vasoactive drugs administered continuously for the first 24 hours of admission to be independently associated to mortality.

CONCLUSIONS

Advanced age, acute renal failure and the need for vasoactive drugs were associated to an increased risk of mortality in patients with urinary sepsis associated to upper urinary tract calculi.

Efficacy and safety of intravenous sulbactam/ampicillin 3 g 4 times daily in Japanese adults with moderate to severe community-acquired pneumonia: a multicenter, open-label, uncontrolled study

Although sulbactam/ampicillin (SBT/ABPC) 3 g 4 times daily (QID) is widely used worldwide for patients with moderate to severe community-acquired pneumonia (CAP), the 3 g QID regimen was not available in Japan. In fact, there has been no evidence from a formal clinical study regarding the efficacy and safety of SBT/ABPC 3 g QID in these patients. We report the first results of a multicenter, unblinded, non-comparative, phase 3 study of SBT/ABPC 3 g QID in Japanese adults with moderate to severe CAP. Forty-seven subjects with moderate to severe CAP were enrolled and received SBT/ABPC 3 g QID intravenously for 3-14 days. The clinical responses assessed by the data review committee (DRC) were the primary endpoints. The secondary endpoints included the bacteriological responses assessed by the DRC. The clinical efficacy rate at the test of cure (TOC) was 94.6%. The bacterial eradication rate at TOC was 91.7%. Causative pathogens were isolated from sputum sample taken at baseline in 28 subjects (59.6%). Common causative pathogens included Streptococcus pneumoniae (14 strains), Haemophilus influenzae (9 strains), and Moraxella catarrhalis (8 strains). The clinical efficacy rate and the bacterial eradication rate at TOC of the common pathogens were, respectively, 92.3% and 90.0% in subjects with S. pneumoniae, 83.3% and 75.0% in subjects with H. influenzae, and 87.5% and 87.5% in subjects with M. catarrhalis. All treatment-related adverse events were mild or moderate in severity. SBT/ABPC 3 g QID was well tolerated and demonstrated excellent clinical and bacteriological responses. ClinicalTrials.gov Identifier: NCT01189487.

Expression of marA is remarkably increased from the early stage of development of fluoroquinolone-resistance in uropathogenic Escherichia coli

BACKGROUND

Analyses of efflux pumps overexpression and mutations in quinolone resistance determining region (QRDR) in early stage of development of resistance to fluoroquinolones (FQs) are valuable to discuss countermeasures against them. We induced levofloxacin (LVFX)-resistant strains from susceptible uropathogenic Escherichia coli in vitro to analyze the mechanisms of development of FQs-resistance.

METHODS

89 strains were exposed to discontinuous elevation of LVFX dose, and mRNA level of efflux pumps and their regulators as well as mutations developed in QRDR of LVFX-resistant strains were analyzed.

RESULTS

In 5 strains, a stepwise increase in MIC to LVFX (up to >128 μg/ml)was observed. Compared to the parent strains, additional mutations in QRDR were observed in the strains developing high MIC. Remarkable increase of marA expression was observed even in the early stage of LVFX-resistance development, and it lasted until high-level resistance was developed. On the other hand, moderate increase in acrB expression but only low increase in yhiU, yhiV, mdfA, tolC and sdiA were observed.

CONCLUSIONS

These results suggested that marA expression is a sensitive marker for early detection of development of LVFX-resistance.

Clinical effectiveness and safety of tazobactam/piperacillin 4.5 g for the prevention of febrile infectious complication after prostate biopsy

We investigated the clinical effectiveness and safety of tazobactam/piperacillin (TAZ/PIPC) in a 1:8 ratio, a β-lactamase inhibitor with penicillin antibiotic, for the prevention of febrile infectious complication after prostate biopsy. Each patient received a single dose of TAZ/PIPC 4.5 g, 30 min before the biopsy in Group 1 or TAZ/PIPC 4.5 g twice, once 30 min before and once after the biopsy (just before discharge or 5 h after the biopsy), in Group 2. Estimation of efficacy was performed within 1-month after prostate biopsy. Clinical diagnosis of febrile infectious complication was based on a body temperature elevation greater than 38 °C. Infectious complication after prostate biopsy was detected in 2.5% (4/160 patients) in Group 1 and in 0.45% (2/442 patients) in Group 2. All of the patients with febrile infectious complication had risk factors: 5 patients had voiding disturbance, 2 patients had diabetes mellitus and 1 patient had steroid dosing. In group 1, 88 patients had at least one risk factor and 72 patients had no risk factors. Of the patients with a risk factor, 4 had febrile infectious complication after prostate biopsy, but there was no significant difference between the two groups. In group 2, 87 patients had at least one risk factor and 255 patients had no risk factors. The patients with a risk factor had febrile infectious complication significantly more frequently than did patients without a risk factor (P = 0.038). Therefore, TAZ/PIPC appears to be effective as preoperative prophylaxis against the occurrence of febrile infectious complication after prostate biopsy.

Treatment of acute uncomplicated cystitis with faropenem for 3 days versus 7 days: multicentre, randomized, open-label, controlled trial

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.

Interactions of Pseudomonas aeruginosa in predominant biofilm or planktonic forms of existence in mixed culture with Escherichia coli in vitro

Pseudomonas aeruginosa and Escherichia coli are known to be involved in mixed communities in diverse niches. In this study we examined the influence of the predominant form of cell existence of and the exometabolite production by P. aeruginosa strains on interspecies interactions, in vitro. Bacterial numbers of P. aeruginosa and E. coli in mixed plankton cultures and biofilms compared with their numbers in single plankton cultures and biofilms changed in a different way, but were in accordance with the form of P. aeruginosa cell existence. The mass of a mixed-species biofilm was greater than the mass of a single-species biofilm. Among the mixed biofilms, the one with the "planktonic" P. aeruginosa strain had the least biomass. The total pyocyanin and pyoverdin levels were found to be lower in all mixed plankton cultures. Despite this, clinical P. aeruginosa strains irrespective of the predominant form of existence ("biofilm" or "planktonic") had a higher total concentration of exometabolites than did the reference strain in 12-24 h mixed cultures. The metabolism of E. coli, according to its bioluminescence, was reduced in mixed cultures, and the decrease was by 20- to 100-fold greater with the clinical Pseudomonas strains than the reference Pseudomonas strain. Thus, both the predominant form of existence of and the exometabolite production by distinct P. aeruginosa strains should be considered to fully understand the interspecies relationship and bacteria survival in natural communities.

Ciprofloxacin Resistance in Enterococcus faecalis Strains Isolated From Male Patients With Complicated Urinary Tract Infection

PURPOSE

Urinary tract infection (UTI) is one of the most prevalent bacterial infections, and fluoroquinolone therapy is a well-known standard regimen for UTI. The prevalence and risk factor analysis of fluoroquinolone resistance in enterococcal UTIs are not well documented. The aim of this study was to evaluate the antimicrobial susceptibility and risk factors for ciprofloxacin resistance in Enterococcus faecalis strains isolated from patients with complicated UTI.

MATERIALS AND METHODS

We evaluated 81 E. faecalis strains isolated from 81 male patients at a single teaching hospital over 3 years. The Vitek 2 automatic system was used for antimicrobial susceptibility analysis.

RESULTS

Antimicrobial resistance rates were rare for ampicillin/sulbactam, imipenem, and vancomycin in E. faecalis. Forty-six percent of the E. faecalis strains were resistant to levofloxacin, 47% were resistant to ciprofloxacin, and 58% were resistant to norfloxacin. E. faecalis strains were highly resistant to erythromycin (92%) and ftetracycline (96%). The risk factor analysis revealed that age intervals, the underlying diseases, catheterization, and the number of admissions did not increase the risk of ciprofloxacin resistance, whereas patients with hospital-acquired infection (odds ratio [OR], 18.15; 95% confidence interval [CI], 3.46 to 95.13; p=0.001), patients who were treated in a urological department (OR, 6.15; 95% CI, 1.5 to 25.41; p=0.012), and patients who were transferred from health care centers (OR, 7.393; 95% CI, 1.32 to 41.22; p=0.023) had an increased risk of ciprofloxacin resistance compared with the matched controls.

CONCLUSIONS

Ciprofloxacin is no longer a recommended therapy for E. faecalis from complicated UTI in men with risk factors. We suggest that ampicillin/sulbactam can be recommended as alternatives for treating ciprofloxacin-resistant E. faecalis strains associated with UTI in Korea.

Synthesis and Antimicrobial Evaluation of a New Series ofN-1,3-Benzothiazol-2-ylbenzamides

Enterococcus faecalisis a Gram-positive commensal inhabitant of the intestinal tract of humans, animals, and insects. However, it is also an opportunistic pathogen and has emerged as a leading cause of hospital-acquired extraintestinal infections. Fluoroquinolones have been frequently used to treatE. faecalisinfections, and the emergence of fluoroquinolone-resistantE. faecalisstrains has recently been reported in several countries. Thus, the identifications of new antibiotics specifically directed toE. faecalismay be envisaged. In this paper, a new series ofN-1,3-benzothiazol-2-ylbenzamides have been designed, synthesized, and evaluated for theirin vitroantimicrobial activities. Among the tested compounds,3iwas active againstE. faecalis.

The efficacy of sequential therapy using pazufloxacin followed by oral fluoroquinolones for treatment of pyelonephritis

The efficacy of sequential therapy of pazufloxacin (PZFX), which is a parenteral fluoroquinolone, followed by oral fluoroquinolones [tosufloxacin tosilate (TFLX) or levofloxacin (LVFX)] for treatment of pyelonephritis, was evaluated. Patients with pyelonephritis who had fever (≥37.5 °C), pyuria (≥10 white blood cells/high-power field), and bacteriuria (≥10(4) colony-forming units/ml) were eligible for this study. PZFX (500 mg) was given intravenously twice a day for at least 3 days. If the patients were clinically improved, TFLX (150 mg) or LVFX (100 mg) was then administered orally three times a day for at least 5 days. Patients underwent clinical and microbiological evaluation at 5-9 days after final drug administration. Clinical and microbiological efficacy could be assessed in 21 of 25 cases enrolled. Both clinical and microbiological efficacy rates were 81.0 % (17/21 cases). In the effective cases, the mean administration time was 4.2 days for PZFX and 6.0 days for oral fluoroquinolones. The mean time to defervescence was 3.4 days for the effective cases. In the four treatment failure cases, three quinolone-resistant Escherichia coli and a quinolone-resistant Enterococcus faecalis were isolated. This sequential therapy seemed to be clinically effective in the treatment of pyelonephritis; however, the prevalence of quinolone-resistant E. coli should be taken into account.

Serratia infections: from military experiments to current practice

Serratia species, in particular Serratia marcescens, are significant human pathogens. S. marcescens has a long and interesting taxonomic, medical experimentation, military experimentation, and human clinical infection history. The organisms in this genus, particularly S. marcescens, were long thought to be nonpathogenic. Because S. marcescens was thought to be a nonpathogen and is usually red pigmented, the U.S. military conducted experiments that attempted to ascertain the spread of this organism released over large areas. In the process, members of both the public and the military were exposed to S. marcescens, and this was uncovered by the press in the 1970s, leading to U.S. congressional hearings. S. marcescens was found to be a certain human pathogen by the mid-1960s. S. marcescens and S. liquefaciens have been isolated as causative agents of numerous outbreaks and opportunistic infections, and the association of these organisms with point sources such as medical devices and various solutions given to hospitalized patients is striking. Serratia species appear to be common environmental organisms, and this helps to explain the large number of nosocomial infections due to these bacteria. Since many nosocomial infections are caused by multiply antibiotic-resistant strains of S. marcescens, this increases the danger to hospitalized patients, and hospital personnel should be vigilant in preventing nosocomial outbreaks due to this organism. S. marcescens, and probably other species in the genus, carries several antibiotic resistance determinants and is also capable of acquiring resistance genes. S. marcescens and S. liquefaciens are usually identified well in the clinical laboratory, but the other species are rare enough that laboratory technologists may not recognize them. 16S rRNA gene sequencing may enable better identification of some of the less common Serratia species.

Mechanisms of and risk factors for fluoroquinolone resistance in clinical Enterococcus faecalis isolates from patients with urinary tract infections

We examined Enterococcus faecalis strains clinically isolated from 100 patients with urinary tract infections (UTIs) for their susceptibility to levofloxacin (LVX) by measuring the MIC and investigated amino acid mutations by direct DNA sequencing, which were then correlated with LVX resistance. Next, we studied risk factors for LVX resistance, such as age, gender, and previous fluoroquinolone use, and investigated the statistical correlation of these risk factors with each amino acid mutation and LVX resistance. Of the 100 isolates tested, 14 isolates showed LVX resistance and all of these isolates had amino acid mutations. We demonstrated that 2 out of 4 mutations (Ser83-to-Ile in gyrA and Ser80-to-Ile in parC) had a significant correlation with LVX resistance. There was a significant relationship between isolates with 2 or 3 amino acid mutations and LVX resistance. In addition, we found a significant correlation between the previous use of fluoroquinolones and LVX resistance or the presence of mutations and also demonstrated that previous use of other types of antibiotics was significantly related to the presence of mutations by multivariate analysis. In conclusion, we found significant correlation between amino acid mutations in E. faecalis, LVX resistance, and risk factors such as previous use of fluoroquinolones.