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

Review of the In Vitro Microbiological Activity of Mecillinam Against Common Uropathogens in Uncomplicated Urinary Tract Infection: Focus on Resistant Pathogens

Antimicrobial resistance in uropathogens commonly causing urinary tract infections (UTIs) is a growing problem internationally. Pivmecillinam, the oral prodrug of mecillinam, has been used for over 40 years, primarily in Northern Europe and Canada. It is recommended in several countries as a first-line agent for the treatment of uncomplicated UTIs (uUTIs) and is now approved in the United States. We performed a structured literature search to review the available evidence on susceptibility of common uUTI-causing uropathogens to mecillinam. Among 38 studies included in this literature review, susceptibility rates for Escherichia coli to mecillinam-including resistant phenotypes such as extended-spectrum β-lactamase-producing E. coli-exceed 90% in most studies. High rates of susceptibility were also reported among many other uropathogens including Klebsiella spp., Enterobacter spp., and Citrobacter spp. In the current prescribing climate within the United States, pivmecillinam represents a viable first-line treatment option for patients with uUTI.

[Therapy of cystitis with nitroxoline-NitroxWin : Prospective, multicenter, non-interventional study and microbiological resistance surveillance]

BACKGROUND

According to German AWMF S3 guideline nitroxoline is recommended as one of the first-choice antibiotics for treatment of acute uncomplicated cystitis (UC) in women. Under real-world conditions the clinical efficacy of nitroxoline should be checked in a noninterventional, prospective and multicenter study (NIS) and the prevalence of nitroxoline resistance in E. coli be monitored.

MATERIALS AND METHODS

Female patients with UC treated with nitroxoline (recommended dosage 250 mg tid for 5 days) were included by urologists, general practitioners (GPs), and internists in family medicine throughout Germany from April-December 2022 and followed for 21-28 days. The diagnosis and course of therapy were judged by the Acute Cystitis Symptom Score (ACSS) questionnaire and laboratory investigations (leukocyturia etc). Separately, a nationwide resistance surveillance was performed during 2019-2020 in collaboration with 23 laboratories to collect urinary E. coli isolates and test their susceptibility to nitroxoline.

RESULTS

Of the 316 patients with mean (SD) age of 57.2 (±20.4 [median 62.5]) years who were included in the NIS, 193/248 (86.3%) in the per-protocol group and in 193/263 (81.44%) in the intention-to-treat group were clinically successful. Furthermore, 96% of the patients rated the tolerability of nitroxoline as "very good" or "good". All 272 E. coli isolates tested were susceptible to nitroxoline.

CONCLUSIONS

Nitroxoline showed very good clinical results in the NIS, and 100% of the tested E. coli urine isolates were susceptible to nitroxoline. Nitroxoline can still be recommended as one of the first-choice antibiotics for treatment of UC in women.

Antimicrobial Resistance in Urinary Tract Infections: Is There an Issue and Does It Matter?

Antimicrobial resistance (AMR) has increased substantially among community-acquired uropathogens that cause urinary tract infections (UTI), limiting the availability of effective oral antibiotic treatments. This review includes coverage of an expert-led Learning Lounge, symposium session, and several poster presentations, that took place between 20th–22nd October 2022 as part of IDWeek2022 in Washington, D.C., USA. An immersive Learning Lounge, sponsored by GSK, opened with Keith Kaye, Department of Medicine, Rutgers–Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA, who illuminated the concerns of AMR in community-acquired UTIs, delivering contemporary surveillance data, and outlined how in vitro data may translate into practical advice. This led fittingly to Erin McCreary, Division of Infectious Diseases, Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania, USA, who enquired whether enough is being done in clinical practice regarding community-acquired infections, highlighting the importance of antimicrobial stewardship (AMS), and galvanising the audience to adapt healthcare settings to the changing landscape. The scientific programme also included three data-rich posters that showcased Kaye’s surveillance data on Escherichia coli and Klebsiella pneumoniae co-resistance, along with the geographical distribution of K. pneumoniae. An insightful poster by Claire Trennery, Value Evidence Outcomes, GSK, Brentford, UK, considered the patient perspective of UTI symptoms in defining antibiotic treatment success, and two posters presented by Rodrigo Mendes, JMI Laboratories, North Liberty, Iowa, USA, examined in vitro global surveillance data of emerging antimicrobial treatments.

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

BACKGROUND

Escherichia coli is the leading pathogen of community-acquired urinary tract infections. Gepotidacin is a novel, bactericidal, first-in-class triazaacenaphthylene oral antibiotic that inhibits bacterial DNA replication by a distinct mechanism of action that confers activity against most strains of target pathogens, such as E. coli, Staphylococcus saprophyticus and Neisseria gonorrhoeae, including those resistant to other antibiotics.

OBJECTIVES

This study assessed the in vitro activity of gepotidacin in comparison with ciprofloxacin and other oral standard-of-care antibiotics using a large collection of urine isolates of E. coli obtained from outpatients in Germany.

METHODS

Four hundred and sixty E. coli collected from 23 laboratories during a surveillance study in 2019/2020 were tested. Forty-six isolates (10.0%) produced an ESBL of the CTX-M family, half of which belonged to MDR clonal subgroups of E. coli ST131. Antibiotic susceptibilities were tested at a reference laboratory by broth microdilution according to the standard ISO 20776-1.

RESULTS

Fifty-three (11.5%) isolates were ciprofloxacin resistant, 25 (47.2%) of which also produced an ESBL. Overall, MIC50/90 values for gepotidacin were 2/4 mg/L (MIC range 0.125-16 mg/L), with no differences in activity between ciprofloxacin-susceptible and ciprofloxacin-resistant isolates, ESBL-producing and non-ESBL isolates, O25b-ST131 isolates, and isolates susceptible or resistant to fosfomycin, mecillinam or nitrofurantoin.

CONCLUSIONS

Gepotidacin showed promising in vitro activity against urine isolates of E. coli, including ciprofloxacin-resistant isolates, ESBL-producing isolates and isolates resistant to oral standard-of-care antibiotics.

Prior Antibiotic Use Increases Risk of Urinary Tract Infections Caused by Resistant Escherichia coli among Elderly in Primary Care: A Case-Control Study

We investigated whether prior use of antibiotics affects the risk of mecillinam/trimethoprim/nitrofurantoin/multi-resistant Escherichia coli urinary tract infection (UTI) among elderly patients in general practice. Data on urine culture came from urine samples performed in general practice and sent to hospitals in the Capital Region of Denmark, and prescription data came from a nationwide prescription database. The study population consisted of patients with UTI episodes (n = 41,027) caused by E. coli that received a concurrent antibiotic prescription against UTI from 2012 to 2017. We used a case-control design. Cases were UTI episodes caused by mecillinam, trimethoprim, nitrofurantoin or multi-resistant E. coli and controls were UTI episodes caused by E. coli not displaying the respective resistance pattern. We analyzed whether exposure to antibiotics in a period of 8-90 days prior to the UTI episode affected the risk of antibiotic resistant uropathogenic E coli. The analyses were adjusted for age, sex, hospital admission and nursing home status. The odds of resistance to all of the four antibiotics increased significantly after exposure to antibiotics within 90 days prior to the UTI episode. In general, mecillinam showed the lowest increase in the odds for selection of resistance. The results indicate that mecillinam is a favorable antibiotic choice in terms of selection of resistance.

Molecular Characterization of Extended Spectrum β-Lactamase (ESBL) and Virulence Gene-Factors in Uropathogenic Escherichia coli (UPEC) in Children in Duhok City, Kurdistan Region, Iraq

Background: The presence of extended-spectrum β-lactamase (ESBL)-producing bacteria among uropathogens is significantly increasing in children all over the world. Thus, this research was conducted to investigate the prevalence of E. coli and their antimicrobial susceptibility pattern, and both genes of ESBL-producing E. coli resistant and virulence factor in UTIs patients among children in Duhok Province, Kurdistan, Iraq. Method: a total of 67 E. coli were identified from 260 urine samples of pediatric patients diagnosed with UTIs aged (0−15 years) which were collected from Heevi Pediatric Teaching Hospital, from August 2021 to the end of February 2022. Result: a high proportion of UPEC infections at ages <5 years and the rates among girls (88%) were significantly higher than those among the boys. A wide variety of E. coli are resistant to most antibiotics, such as Amoxicillin, Ampicillin and Tetracycline, and 64% of them were positive for ESBL. Interestingly, the presence of both the ESBL marker genes (blaTEM, and blaCTX-M) as well as both virulence marker genes (pai and hly) were detected in above 90% of E. coli. Conclusion: the data illustrate an alarming increase in UPEC with ESBL production and the emergence of multidrug-resistant drugs in the early age of children. The public health sectors should further monitor the guidelines of using antibiotics in Kurdistan, Iraq.