Antimicrobial resistance of clinical Enterobacterales isolates from urine samples, Germany, 2016 to 2021.

IntroductionEmpirical therapy for the treatment of urinary tract infections should be tailored to the current distribution and susceptibility of potential pathogens to ensure optimal treatment.AimWe aimed to provide an up-to-date overview of the epidemiology and susceptibility of Enterobacterales isolated from urine in Germany.MethodsWe retrospectively analysed antimicrobial susceptibility data from 201,152 urine specimens collected between January 2016 and June 2021 from in- and outpatients. Multiple logistic regression analysis was used to evaluate the association between year of investigation and antibiotic resistance, adjusted for age, sex and species subgroup. Subgroup analyses were performed for midstream urine samples obtained from (i) female outpatients aged 15 to 50 years, (ii) female outpatients older than 50 years and (iii) male outpatients.ResultsResistance rates of less than 20% were observed for nitroxoline (3.9%), fosfomycin (4.6%), nitrofurantoin (11.7%), cefuroxime (13.5%) and ciprofloxacin (14.2%). Resistance to trimethoprim/sulfamethoxazole (SXT) (20.1%), amoxicillin-clavulanic acid (20.5%), trimethoprim (24.2%), pivmecillinam (29.9%) and ampicillin (53.7%) was considerably higher. In the subgroup of outpatient women aged 15-50 years, resistance rates were generally lower. Resistance rates of all antibiotics decreased from 2016 to 2021. Multiple logistic regression revealed the lowest adjusted odds ratio (ORadj) of 0.838 (95% confidence interval (CI): 0.819-0.858; p < 0.001) for pivmecillinam and the highest ORadj of 0.989 (95% CI: 0.972-1.007; p = 0.226) for nitrofurantoin.ConclusionsResistance has generally decreased over the past years, independent of sex, age and causative pathogen. Our data provide an important basis for empirical antibiotic recommendations in various settings and patient collectives.

Pivmecillinam, the paradigm of an antibiotic with low resistance rates in Escherichia coli urine isolates despite high consumption.

OBJECTIVES: Pivmecillinam, the oral version of mecillinam, represents one of the major recommended and used antibiotics for empiric and targeted treatment of urinary tract infections in primary care in Denmark, Norway and Sweden. Mecillinam resistant mutants in Escherichia coli develop easily in vitro, but their fitness cost has been shown to be high. METHODS: We revisited the resistance and consumption data from the monitoring programmes in the three countries and compared pivmecillinam with ciprofloxacin from 2010 to 2020. RESULTS: Mecillinam resistance rates in Escherichia coli remained around 6% in Denmark and Norway relative to a constant consumption in Norway of 1.6-1.8 DID (defined daily doses per 1000 inhabitants per day), and even increasing in Denmark from 1.6 to 2.3 DID. In Sweden resistance was significantly lower at 4% related to the lower consumption of 0.5 DID. For ciprofloxacin, resistance rates fluctuated around 6%-12%, highest in Sweden with the highest consumption (0.8-0.6 DID) and lowest in Denmark (0.55-0.35 DID) and Norway (0.7-0.3 DID), although consumption declined significantly in all three countries. CONCLUSIONS: Pivmecillinam is an example of an antibiotic, which easily develops resistance in vitro, but apparently can be used broadly in primary care without increase in resistance rates.

The efficacy of pivmecillinam in oral step-down treatment in hospitalised patients with E. coli bacteremic urinary tract infection; a single-arm, uncontrolled treatment study.

BACKGROUND: The role of oral beta-lactam antibiotics in treating febrile urinary tract infections (UTI) is not yet definite. Today, fluoroquinolones together with trimethoprim-sulfamethoxazole (TMP-MTX) are considered standard of care and often the only available evidence-based oral treatment for febrile UTI. This study clarifies the efficacy and safety of pivmecillinam (PIV) used as step-down therapy for bacteremic urinary tract infection (UTI). METHODS: A single-arm, uncontrolled treatment trial was conducted in the period September 2017-March 2020. Candidates for inclusion were men and women suffering from E. coli bacteremia due to UTI and were consecutively included in a Norwegian hospital. Exclusion criteria were among others: other ongoing bacterial infection, septic shock, pyonephrosis/abscess and pregnancy. After 3 days of parenteral antibiotic, the treatment was converted to the study drug; oral PIV 400 mg QID for 1 week. Primary endpoint was a combination of three elements; afebrility, no need for retreatment and improvement in self-reported health status. Test Of Cure (TOC) was 1 week post-treatment. Secondary endpoints included among others microbiological efficacy and CRP value < 30 mg/L. RESULTS: Of 476 screened subjects, 53 patients were included. Median age was 67 years, 28 (56%) were women. 50 patients were evaluated for per-protocol analysis. 44 of 50 patients (88%) (95% CI [75.7-95.5]) reached the primary endpoint on TOC. 14 of 48 patients (29.2%) had significant growth (> 103 CFU/mL) of E.coli on TOC. CRP-level was strongly associated to treatment outcome, (OR 0.006 [95% CI 0.00-0.11], p < 0.001). CONCLUSIONS: This trial documents that PIV 400 mg QID given for 1 week following 3 days of parenteral antibiotics, is a suitable treatment option in patients suffering from bacteremic UTI due to E. coli. Randomised clinical trials studying the efficacy of PIV vs standard of care of febrile UTI are warranted. Trial registration The trial was registered at ClinicalTrials.gov under the identifier: NCT03282006 13/09/2017 and approved by The Regional Committees for Medical Research Ethics South East Norway (2015/2384/REK sør-øst) and the Norwegian Medicines Agency (SLV; reference No 16/06018-09; EudraCT No 2016-000984-18) before initiation.

Treatment duration of pivmecillinam in men, non-pregnant and pregnant women for community-acquired urinary tract infections caused by Escherichia coli: a retrospective Danish cohort study.

OBJECTIVES: To evaluate the importance of treatment duration for therapeutic efficacy of pivmecillinam for community-acquired urinary tract infections (UTIs) caused by Escherichia coli. METHODS: A retrospective cohort study was conducted between 1 January 2010 and 30 September 2016 in adults with community-acquired E. coli bacteriuria, treated empirically with pivmecillinam. Regimens of 3, 5 and 7 days were compared using clinical treatment failure (i.e. redemption of a new antibiotic or hospitalization due to UTI) within 14 and 30 days as outcome. HR and risk difference with 95% CI were estimated for treatment failure. Results were stratified by age (18-50, 51-70, >70 years) and sex. RESULTS: Of the 21864 cases of E. coli UTI that were analysed, 2524 (11.5%) were in men. In 954 cases (4.4%) E. coli produced ESBL and 125 (13.1%) of the cases were in men. The 3 day regimen increased the risk of treatment failure for all groups. The risk differences between the 3 and 5 day regimens were <10% for women, but >10% for men. Comparing the 7 day and 5 day regimens, only women aged >50 years demonstrated an increased risk of treatment failure within 14 days with the 5 day regimen, but not within 30 days. CONCLUSIONS: With the current data, where data on clinical classification of the E. coli UTI were missing, a 5 day treatment with pivmecillinam at 400 mg three times daily seems to be the rational recommendation for lower UTI in men, pregnant women and women >50 years old. A 3 day regimen seems sufficient for non-pregnant women <50 years old.

In utero exposure to antibiotics and risk of congenital malformations: a population-based study.

BACKGROUND: Antibiotics are commonly prescribed during pregnancy. Although the safety of most penicillins is well established, some controversy and uncertainty are associated with the use of other commonly prescribed antibiotics. OBJECTIVE: To determine the risk of congenital malformations following first-trimester in utero exposure to 10 commonly prescribed antibiotics in Denmark. MATERIALS AND METHODS: This was a cohort study comprising all singleton liveborn children in Denmark between 2000 and 2015. Data on malformations were collected through 2016. Merging validated and comprehensive populationwide Danish healthcare and civic registries, we merged data on pregnancy, prescription drugs purchases during first trimester and congenital malformations. Using logistic regression, we calculated the odds ratio for congenital malformations (any), major congenital malformations, and cardiac congenital malformations for the 10 most commonly prescribed antibiotics (excluding 4 penicillins that served as control). In the primary analysis, the exposed cohort was compared to a cohort exposed to any of 4 penicillins considered safe during pregnancy (ampicillin, pivampicillin, benzylpenicillin, and phenoxymethylpenicillin). In sensitivity analysis, the exposed cohort was compared to an unexposed cohort. Covariate adjustments were made for maternal age at delivery, year of delivery, parity, pre-pregnancy body mass index, smoking, educational status, employment status, and annual personal income. RESULTS: We found no increased risk of congenital malformations to be related to first-trimester in utero exposure to the 10 most commonly prescribed antibiotics in Denmark compared to a cohort of pregnant women exposed to penicillins that are considered safe during pregnancy. Compared to unexposed pregnancies, small increased risks for major malformations and cardiac malformations were apparent for pivmecillinam (odds ratio, 1.13; confidence interval, 1.06-1.19; and odds ratio, 1.15; confidence interval, 1.04-1.28, respectively), sulfamethizole (odds ratio, 1.15; confidence interval, 1.07-1.24; and odds ratio, 1.22; confidence interval, 1.07-1.39, respectively), and azithromycin (odds ratio, 1.19, confidence interval, 1.03-1.38; and odds ratio, 1.29, confidence interval, 0.99-1.67, respectively). CONCLUSION: In this large populationwide cohort study, we found, with a high degree of precision, no increased risk of congenital malformations following first-trimester exposure to 10 commonly prescribed systemic antibiotics.

Prescription of antibiotics for urinary tract infection in general practice in Denmark.

OBJECTIVE: The aim of this study was to describe and characterize the prescription of antibiotics for urinary tract infection (UTI) in general practice in Denmark and to evaluate compliance with current recommendations. DESIGN: National registry-based study Setting: Danish general practice Patients: 267.539 patients who redeemed a prescription for antibiotics with the clinical indication UTI at community pharmacies between July 1st 2012 and June 31st 2013. MAIN OUTCOME MEASURES: Antibiotics prescribed for 1) acute lower UTI, 2) acute upper UTI and 3) recurrent UTI presented as amount of prescriptions, number of treatments per 1000 inhabitants per day (TID) and defined daily doses per 1000 inhabitants per day (DID). RESULTS: A total of 507.532 prescriptions were issued to 267.539 patients during the one year study period, representing 2.35 DID. Acute lower UTI was the most common reason for prescription of antibiotics (89.5%) followed by recurrent UTI (8.4%). The majority of the prescriptions were issued to people above 60 year old (57.6%). Pivmecillinam was the most commonly prescribed antibiotic in acute lower (45.8%) and acute upper (63.3%) UTI. Trimethroprim was the most commonly prescribed antibiotic in recurrent UTI (45.9%). Prescription of quinolones increased with increasing patient-age (p = <.0001). CONCLUSION: Compliance with current Danish recommendations was moderately high. Pivmecillinam is the first line antibiotic for the management of acute lower and upper UTI, and trimethroprim is the first line option of recurrent UTI. A high proportion of the antibiotic prescriptions were issued in the elderly population including a relatively high prescription rate of quinolones. Key points Urinary tract infection (UTI) is a common cause for prescription of antibiotics in general practice Poor compliance in general practice with recommendations for first-line treatment of UTI may increase antibiotic resistance Danish general practitioners are generally compliant with national and regional guidelines for antibiotic treatment of UTI There is high use of antibiotics in the elderly population including a worrisome high use of broad-spectrum antibiotics, such as Quinolones.

Ibuprofen versus pivmecillinam for uncomplicated urinary tract infection in women-A double-blind, randomized non-inferiority trial.

BACKGROUND: Although uncomplicated urinary tract infections (UTIs) are often self-limiting, most patients will be prescribed antibiotic treatment. We assessed whether treatment with ibuprofen was non-inferior to pivmecillinam in achieving symptomatic resolution by day 4, with a non-inferiority margin of 10%. METHODS AND FINDINGS: This was a randomized, controlled, double-blind non-inferiority trial. We recruited patients from 16 sites in a general practice setting in Norway, Sweden, and Denmark. Non-pregnant women aged 18-60 years presenting with symptoms of uncomplicated UTI were screened for eligibility from 11 April 2013 to 22 April 2016. Patients with informed consent were randomized (1:1 ratio) to treatment with either 600 mg ibuprofen or 200 mg pivmecillinam 3 times a day for 3 days. The patient, treating physician, and study personnel were blinded to treatment allocation. The primary outcome was the proportion of patients who felt cured by day 4, as assessed from a patient diary. Secondary outcomes included the proportion of patients in need of secondary treatment with antibiotics and cases of pyelonephritis. A total of 383 women were randomly assigned to treatment with either ibuprofen (n = 194, 181 analyzed) or pivmecillinam (n = 189, 178 analyzed). By day 4, 38.7% of the patients in the ibuprofen group felt cured versus 73.6% in the pivmecillinam group. The adjusted risk difference with 90% confidence interval was 35% (27% to 43%) in favor of pivmecillinam, which crossed the prespecified non-inferiority margin. Secondary endpoints were generally in favor of pivmecillinam. After 4 weeks' follow-up, 53% of patients in the ibuprofen group recovered without antibiotic treatment. Seven cases of pyelonephritis occurred, all in the ibuprofen group, giving a number needed to harm of 26 (95% CI 13 to 103). Five of these patients were hospitalized and classified as having serious adverse events; 2 recovered as outpatients. A limitation of the study was the extensive list of exclusion criteria, eliminating almost half of the patients screened. We did not register symptoms in the screening process; hence, we do not know the symptom burden for those who declined to participate. This might make our results less generalizable. CONCLUSIONS: Ibuprofen was inferior to pivmecillinam for treating uncomplicated UTIs. More than half of the women in the ibuprofen group recovered without antibiotics. However, pyelonephritis occurred in 7 out of 181 women using ibuprofen. Until we can identify those women who will develop complications, we cannot recommend ibuprofen alone as initial treatment to women with uncomplicated UTIs. TRIAL REGISTRATION: ClinicalTrials.gov NCT01849926 EU Clinical Trials Register (EU-CTR), EudraCT Number 2012-002776-14.

Antibiotic prescription and clinical management of common infections among general practitioners in Latvia, Lithuania, and Sweden: a pilot survey with a simple protocol.

Comparative information on diagnosis-related antibiotic prescribing patterns are scarce from primary care within and between countries. To describe and compare antibiotic prescription and routine management of infections in primary care in Latvia (LV), Lithuania (LT) and two study sites in Sweden (SE), a cross-sectional observational study on patients who consulted due to sypmtoms compatible with infection was undetraken. Infection and treatment was detected and recorded by physicians only. Data was collected from altogether 8786 consecutive patients with infections in the three countries. Although the overall proportion of patients receiving an antibiotic prescription was similar in all three countries (LV and LT 42%, SE 38%), there were differences in the rate of prescription between the countries depending on the respective diagnoses. While penicillins dominated among prescriptions (LV 58%, LT 67%, SE 70%), phenoxymethylpenicillin was most commonly prescribed in Sweden (57% of all penicillins), while it was amoxicillin with or without clavulanic acid in Latvia (99%) and Lithuania (85%) respectively. Pivmecillinam and flucloxacillin, which accounted for 29% of penicillins in Sweden, were available neither in Latvia nor in Lithuania. The applied methodology was simple, and provided useful information on differences in treatment of common infections in ambulatory care in the absence of available computerized diagnosis-prescription data. Despite some limitations, the method can be used for assessment of intention to treat and compliance to treatment guidelines and benchmarking locally, nationally, or internationally, just as the point prevalence surveys (PPS) protocols have been used in hospitals all over Europe.

Characteristics of gram-negative urinary tract infections caused by extended spectrum beta lactamases: pivmecillinam as a treatment option within South Dublin, Ireland.

BACKGROUND: The prevalence of urinary tract infections (UTIs) caused by extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae is increasing and the therapeutic options are limited, especially in primary care. Recent indications have suggested pivmecillinam to be a suitable option. This pilot study aimed to assess the viability of pivmecillinam as a therapeutic option in a Dublin cohort of mixed community and healthcare origin. METHODS: A prospective measurement of mean and fractional inhibitory concentrations of antibiotic use in 95 patients diagnosed with UTI caused by ESBL-producing Enterobacteriaceae was carried out. 36 % patients were from general practice, 40 % were admitted to hospital within south Dublin, and 25 % samples arose from nursing homes. EUCAST breakpoints were used to determine if an isolate was sensitive or resistant to antibiotic agents. RESULTS: Sixty-nine percent of patients (N = 66) with urinary ESBL isolates were female. The mean age of females was 66 years compared with a mean age of 74 years for males. Thirty-six percent of isolates originated from primary care, hospital inpatients (26 %), and nursing homes (24 %). The vast majority of ESBL isolates were E. coli (80 %). The E tests for mecillinam and co-amoxiclav had concentration ranges from 0.16 mg/L up to 256 mg/L. The mean inhibitory concentration (MIC) of mecillinam ranged from 0.25 to 256 mg/L, while co-amoxiclav MICs ranged from 6 to 256 mg/L. The percentage of isolates resistant to mecillinam and co-amoxiclav was found to be 5.26 and 94.74 % respectively. CONCLUSIONS: This is the first study exploring the use of pivmecillinam in an Irish cohort and has demonstrated that its use in conjunction with or without co-amoxiclav is an appropriate and useful treatment for urinary tract infections caused by ESBL-producing organisms.

Clinical and bacteriological effects of pivmecillinam for ESBL-producing Escherichia coli or Klebsiella pneumoniae in urinary tract infections.

OBJECTIVES: The prevalence of urinary tract infections (UTIs) caused by extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae is increasing and the therapeutic options are limited, especially in primary care. Recent indications have suggested pivmecillinam to be a suitable option. Here, we evaluated the clinical and bacteriological effects of pivmecillinam in UTIs caused by ESBL-producing Enterobacteriaceae. METHODS: We carried out a prospective follow-up of 39 patients diagnosed with UTI caused by ESBL-producing Enterobacteriaceae, initiated on pivmecillinam. The patients were from general practice (n = 29) or admitted to hospitals (n = 10) in the Copenhagen area, Denmark (n = 30) or Halland, Sweden (n = 9). Both patients and physicians were asked to complete a questionnaire on the pretreatment signs and symptoms. Patients were asked to send in two more urine samples for culture examination, together with questionnaires for clinical effect, 2-6 and 10-20 days, respectively, after end of treatment. RESULTS: Of the 39 patients included, 30 received a treatment regimen of 400 mg of pivmecillinam three times a day and 9 received 200 mg three times a day. All isolates were susceptible to mecillinam. The bacteriological cure rate was 79% (31/39); 80% (24/30) and 78% (7/9) for 400 and 200 mg three times a day, respectively. Relapse, i.e. ESBL-producing bacteria in the second control urine after previous bacteriological cure, was seen in five patients. Clinical cure was evaluable in 19 patients; 16 had a clinical effect (84%). CONCLUSIONS: Pivmecillinam was proven bacteriologically and clinically effective for treatment of lower UTIs caused by ESBL-producing Enterobacteriaceae.

Prescription of antibiotics for urinary tract infections in outpatient care in Bavaria: An analysis of routine data.

BACKGROUND: Patients with urinary tract infection (UTI) in German outpatient care are usually treated by general practitioners (GPs), as well as by other specialties. To prevent antibiotic resistances and side effects, German guidelines recommend fosfomycin, nitrofurantoin, pivmecillinam and nitroxoline as first-line treatments, and advice against broad-spectrum antibiotics such as fluoroquinolones and cephalosporins. However, data from the European Centre for Disease Prevention and Control indicates a significant proportion of second-line antibiotics in German outpatient care. Our aim was to analyze whether antibiotic prescription has changed over time in accordance with guidelines. In addition, we aimed to investigate whether specialties prescribe different antibiotics for UTIs and whether prescription varies according to patient age and sex. For patients receiving more than one antibiotic, we wanted to determine whether subsequent prescriptions show a change in substances and specialties involved. METHODS: This retrospective study involved routine data (2013 to 2019) provided by the Bavarian Association of Statutory Health Insurance Physicians. Data on diagnoses and prescriptions were transmitted from outpatient care physicians on a quarterly basis. UTI patients ≥12 years were included. RESULTS: We analyzed 1.7 million UTI prescription cases. In females, shares of fluoroquinolones decreased sharply over time, while shares of first-line substances fosfomycin and pivmecillinam increased. Gynecologists showed the highest shares of first-line substances compared to GPs and urologists. Fluoroquinolone shares decreased in all three specialty groups. In females, older patients showed lower shares of first-line substances than younger patients. If a second or third antibiotic was prescribed, fosfomycin shares decreased, while shares of nitrofurantoin, nitroxoline and cephalosporins increased. CONCLUSIONS: Our findings show a trend towards a more guideline-adherent prescribing in the treatment of UTI, with a significant increase of shares of fosfomycin and pivmecillinam, especially in women, and a sharp decrease of shares of fluoroquinolones.

Antimicrobial prescribing in nursing homes in Finland: results of three point prevalence surveys.

PURPOSE: The purpose of this study was to analyse the Finnish European Surveillance of Antimicrobial Consumption (ESAC) nursing home (NH) point prevalence surveys' (PPSs) data in detail, i.e. to evaluate the variability in the prevalence of antimicrobial prescription between NHs and its relationship to resident characteristics. METHODS: All residents present in NHs for ≥ 24 h and receiving systemic antimicrobials on the day of the survey were included. Data on antimicrobials and their indications (prophylaxis or treatment, type of infection) were collected. RESULTS: Three PPSs were performed: eight NHs participated in April and November 2009 and nine in May-September 2010. In total, there were 5,691 eligible residents (range by survey, 1,706-2,320; range by NH, 60-688), 716 (12.6 %; range by NH, 3.2-33.3 %) of which received at least one antimicrobial and 40 residents received two. The most common indication was prophylaxis (487/5,691, 8.6 %), mainly for urinary tract infection (UTI) (460/487, 94.5 %). Of the residents, 269/5,691 (4.7 %, range by NH, 1.5-6.0 %) were on antimicrobial treatment. UTI (119/269; 44.2 %) was the most common indication for treatment. Methenamine (306/756, 40.5 %) was the most commonly used antimicrobial, followed by trimethoprim (13.6 %) and pivmecillinam (11.0 %). In the eight NHs participating in all three surveys, the prevalence of residents receiving antimicrobials decreased from 16.6 to 9.7 %. CONCLUSIONS: Antimicrobial use was common in NHs in Finland and most were used for UTI prophylaxis and treatment. The usage, however, varied among NHs and tended to decrease during the surveys. NHs may benefit from antimicrobial stewardship interventions focused on UTI.

Use of antibiotics in nursing homes--surveillance with different methods.

BACKGROUND: Residents in nursing homes have a heightened risk of developing infections that should be treated with antibiotics. Inappropriate use of antibiotics may generate drug-related problems and increase resistance. In this study, we describe the use of antibiotics in nursing homes on the basis of prevalence surveys and drug sales statistics. MATERIAL AND METHODS: Five nursing homes in Oslo participated in two one-day surveys in 2009. All use of systemic antibiotics was registered. The data collection was undertaken according to a protocol developed by the European Surveillance of Antimicrobial Consumption (ESAC) Network and was part of a European study. The nursing homes' drug sales statistics for systemic antibiotics during 2009, distributed by the number of bed days for each nursing home, were estimated. Information on indications for each antibiotic from the prevalence surveys was collated with sales data to achieve an estimate of how the purchased antibiotics were used. RESULTS: The prevalence surveys showed that more than 8% of the residents received antibiotics. Prophylactic treatment accounted for 33% of the prescriptions. A prevalence of antibiotic use of 10% was estimated from the drug sales statistics. Urinary tract infection was the most frequently registered indication. Pivmecillinam and methenamine were most frequently prescribed and most frequently purchased. Most courses of treatment were prescribed in accordance with the national guidelines for antibiotic use. INTERPRETATION: The results from the drug sales statistics concurred well with the prevalence surveys, and the methods can thus be relevant for purposes of monitoring the use of antibiotics.

[Update on current care guidelines: urinary tract infections]. / Käypä hoito -suosituksen päivitystiivistelmä. Virtsatieinfektiot.

This guideline is focused on the diagnostics and treatment of acute, recurrent and relapsing urinary tract infections in adults and children. Sexually transmitted diseases are not addressed, but must be considered in differential diagnostics. The resistance prevalence of the causative microbes and the ecological adverse effects of antimicrobial agents were considered important factors in selecting optimal therapeutic choices for the guideline. Diagnosis and management of cystitis in otherwise healthy women aged 18-65 years can be based on structured telephone interviews. Primary antimicrobiotic drugs are nitrofurantoin, pivmesillinam and trimetoprim for three days.

Oral treatment options for ambulatory patients with urinary tract infections caused by extended-spectrum-beta-lactamase-producing Escherichia coli.

An increase in extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli has been observed in outpatient settings. Consequently, 100 ESBL-positive E. coli isolates from ambulatory patients with clinically confirmed urinary tract infections were collected by a single laboratory between October 2004 and January 2008. Antimicrobial susceptibility testing was carried out using the oral antibiotics fosfomycin, pivmecillinam, and nitrofurantoin and the parenteral antibiotic ertapenem. Susceptibility rates indicate that fosfomycin (97%), nitrofurantoin (94%), and pivmecillinam (85%) could be considered important oral treatment options.

Antibiotic switch after treatment with UTI antibiotics in male patients.

Background: There is a lack of evidence on treatment of urinary tract infections (UTIs) in male patients in a primary care setting, and whether narrow-spectrum antibiotics are safe and effective.Objectives: To explore antibiotic switch rates after treatment with UTI antibiotics in men over the last 11 years.Material: We analysed data from the Norwegian Prescription Database (NorPD). Men ≥16 years receiving cefalexin, ciprofloxacin, cotrimoxazole, nitrofurantoin, ofloxacin, pivmecillinam or trimethoprim during the period 2008-2018 were included. Antibiotic switch was defined as being prescribed a different antibiotic drug appropriate for UTI within 14 days after initial treatment. We calculated rates of antibiotic switch and corresponding odds ratios for each antibiotic drug.Results: Seven hundred twenty-six thousand and ninety-six (726,096) prescriptions to 429,807 men were defined as possible UTI episodes. Fluoroquinolones, pivmecillinam and cotrimoxazole were most frequently prescribed. Forty-nine thousand five hundred and thirty-one (49,531) (6.8%) of the treatments resulted in antibiotic switch. Compared to cotrimoxazole, the risk of antibiotic switch was higher for pivmecillinam (OR: 2.46; 95% CI, 2.39-2.53) and trimethoprim (OR: 2.12; 95% CI, 2.04-2.20), and lower for fluoroquinolones (OR: 0.40; 95% CI, 0.39-0.42) and cefalexin (OR: 0.28; 95% CI, 0.26-0.30). Treatment duration of ≥7 days and age of ≥50 years were associated with an increased risk of antibiotic switch.Conclusion: Fluoroquinolones and cefalexin were associated with lower antibiotic switch rates than the recommended UTI antibiotics (pivmecillinam, nitrofurantoin and trimethoprim). However, the rates of antibiotic switch following treatment of male patients with first-line empirical UTI antibiotics are relatively low, indicating that the current guidelines are safe.

Microbial risk factors for treatment failure of pivmecillinam in community-acquired urinary tract infections caused by ESBL-producing Escherichia coli.

The aim of this study was to identify microbial risk factors for treatment failure of pivmecillinam in community-acquired urinary tract infections (ca-UTIs) caused by ESBL-producing Escherichia coli. Eighty-nine ESBL-producing E. coli isolated from women suffering from ca-UTIs were included. The susceptibilities to mecillinam were determined using MIC gradient strip. Whole genome sequencing was performed on a MiSeq platform, and genome assembly was performed using SPAdes v3.11.0. Neither mecillinam MICs nor ESBL genotypes were associated with treatment outcome of patients treated with pivmecillinam. Specific STs, however, showed significant differences in treatment outcome. Patients infected with ST131 were more likely to experience treatment failure compared to patients infected with non-ST131 (p 0.02) when adjusted for pivmecillinam dose, mecillinam MIC and severity of infection. Patients infected with ST69 were more often successfully treated compared to patients infected with non-ST69 (p 0.04). Patients infected with blaCTX-M-15 ST131 strains were more likely to experience treatment failure than those infected with non-blaCTX-M-15 ST131 strains (p 0.02). The results suggest that specific STs are associated with the clinical efficacy of pivmecillinam. Further studies with a larger number of strains, including a larger number of mecillinam resistant strains, are needed to confirm these results.

Association between antimicrobial consumption and resistance in Escherichia coli.

During a 9-year study period from 1997 through 2005, the association between antimicrobial resistance rates in Escherichia coli and outpatient antimicrobial consumption was investigated in 20 hospital districts in Finland. A total of 754,293 E. coli isolates, mainly from urine samples, were tested for antimicrobial resistance in 26 clinical microbiology laboratories. The following antimicrobials were studied: ampicillin, amoxicillin-clavulanate, cephalosporins, fluoroquinolones, trimethoprim, trimethoprim-sulfamethoxazole, pivmecillinam, and nitrofurantoin. We applied a protocol used in earlier studies in which the level of antimicrobial consumption over 1 year was compared with the level of resistance in the next year. Statistically significant associations were found for nitrofurantoin use versus nitrofurantoin resistance (P < 0.0001), cephalosporin use versus nitrofurantoin resistance (P = 0.0293), amoxicillin use versus fluoroquinolone resistance (P = 0.0031), and fluoroquinolone use versus ampicillin resistance (P = 0.0046). Interestingly, we found only a few associations between resistance and antimicrobial consumption. The majority of the associations studied were not significant, including the association between fluoroquinolone use and fluoroquinolone resistance.