False amoxicillin/clavulanic acid susceptibility in Bacteroides fragilis using gradient strip tests.

BACKGROUND: Repeatedly, too low MIC results were obtained in Bacteroides fragilis quality assessment strains, using gradient strip tests with a ratio of amoxicillin:clavulanic acid of 2:1. We aimed to find the most accurate available gradient strip tests for susceptibility testing of amoxicillin/clavulanic acid in B. fragilis in comparison with agar dilution with EUCAST methodology and breakpoints. METHODS: Twenty-seven clinical B. fragilis isolates were investigated using gold standard EUCAST amoxicillin/clavulanic acid agar dilution (fixed clavulanic acid concentration at 2 mg/L, with increasing amoxicillin concentrations) as well as three commercial gradient strip tests: XL (ratio), AUG (ratio) or AMC (fixed concentration). RESULTS: Using agar dilution (fixed concentration), 19 isolates were susceptible, 1 isolate was susceptible increased exposure (I) and 7 isolates were resistant. Categorical agreement of the gradient strip tests with agar dilution (fixed concentration) was 70% for XL (ratio), 71% for AUG (ratio) and 89% for AMC (fixed concentration). Very major error rates in comparison with agar dilution (fixed concentration) were 100%, 0%, and 0%, respectively. CONCLUSIONS: EUCAST breakpoint usage in amoxicillin/clavulanic acid susceptibility tests for B. fragilis should be accompanied by EUCAST methodology. When using alternative methods such as gradient strip tests, a higher degree of alignment with EUCAST methodology, such as using fixed clavulanic acid concentrations, improves precision.

Empiric antibiotic treatment for urinary tract infection in preschool children: susceptibilities of urine sample isolates.

BACKGROUND: Antibiotic treatment recommendations based on susceptibility data from routinely submitted urine samples may be biased because of variation in sampling, laboratory procedures and inclusion of repeat samples, leading to uncertainty about empirical treatment. OBJECTIVE: To describe and compare susceptibilities of Escherichia coli cultured from routinely submitted samples, with E. coli causing urinary tract infection (UTI) from a cohort of systematically sampled, acutely unwell children. METHODS: Susceptibilities of 1458 E. coli isolates submitted during the course of routine primary care for children <5 years (routine care samples), compared to susceptibilities of 79 E. coli isolates causing UTI from 5107 children <5 years presenting to primary care with an acute illness [systematic sampling: the Diagnosis of Urinary Tract infection in Young children (DUTY) cohort]. RESULTS: The percentage of E. coli sensitive to antibiotics cultured from routinely submitted samples were as follows: amoxicillin 45.1% (95% confidence interval: 42.5-47.7%); co-amoxiclav using the lower systemic break point (BP) 86.6% (84.7-88.3%); cephalexin 95.1% (93.9-96.1%); trimethoprim 74.0% (71.7-76.2%) and nitrofurantoin 98.2% (97.4-98.8%). The percentage of E. coli sensitive to antibiotics cultured from systematically sampled DUTY urines considered to be positive for UTI were as follows: amoxicillin 50.6% (39.8-61.4%); co-amoxiclav using the systemic BP 83.5% (73.9-90.1%); co-amoxiclav using the urinary BP 94.9% (87.7-98.4%); cephalexin 98.7% (93.2-99.8%); trimethoprim 70.9% (60.1-80.0%); nitrofurantoin 100% (95.3-100.0%) and ciprofloxacin 96.2% (89.4-98.7%). CONCLUSION: Escherichia coli susceptibilities from routine and systematically obtained samples were similar. Most UTIs in preschool children remain susceptible to nitrofurantoin, co-amoxiclav and cephalexin.

Global prevalence of antibiotic resistance in paediatric urinary tract infections caused by Escherichia coli and association with routine use of antibiotics in primary care: systematic review and meta-analysis.

OBJECTIVES: To systematically review studies investigating the prevalence of antibiotic resistance in urinary tract infections caused by Escherichia coli in children and, when appropriate, to meta-analyse the relation between previous antibiotics prescribed in primary care and resistance. DESIGN AND DATA ANALYSIS: Systematic review and meta-analysis. Pooled percentage prevalence of resistance to the most commonly used antibiotics in children in primary care, stratified by the OECD (Organisation for Economic Co-operation and Development) status of the study country. Random effects meta-analysis was used to quantify the association between previous exposure to antibiotics in primary care and resistance. DATA SOURCES: Observational and experimental studies identified through Medline, Embase, Cochrane, and ISI Web of Knowledge databases, searched for articles published up to October 2015. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies were eligible if they investigated and reported resistance in community acquired urinary tract infection in children and young people aged 0-17. Electronic searches with MeSH terms and text words identified 3115 papers. Two independent reviewers assessed study quality and performed data extraction. RESULTS: 58 observational studies investigated 77,783 E coli isolates in urine. In studies from OECD countries, the pooled prevalence of resistance was 53.4% (95% confidence interval 46.0% to 60.8%) for ampicillin, 23.6% (13.9% to 32.3%) for trimethoprim, 8.2% (7.9% to 9.6%) for co-amoxiclav, and 2.1% (0.8 to 4.4%) for ciprofloxacin; nitrofurantoin was the lowest at 1.3% (0.8% to 1.7%). Resistance in studies in countries outside the OECD was significantly higher: 79.8% (73.0% to 87.7%) for ampicillin, 60.3% (40.9% to 79.0%) for co-amoxiclav, 26.8% (11.1% to 43.0%) for ciprofloxacin, and 17.0% (9.8% to 24.2%) for nitrofurantoin. There was evidence that bacterial isolates from the urinary tract from individual children who had received previous prescriptions for antibiotics in primary care were more likely to be resistant to antibiotics, and this increased risk could persist for up to six months (odds ratio 13.23, 95% confidence interval 7.84 to 22.31). CONCLUSIONS: Prevalence of resistance to commonly prescribed antibiotics in primary care in children with urinary tract infections caused by E coli is high, particularly in countries outside the OECD, where one possible explanation is the availability of antibiotics over the counter. This could render some antibiotics ineffective as first line treatments for urinary tract infection. Routine use of antibiotics in primary care contributes to antimicrobial resistance in children, which can persist for up to six months after treatment.

Childhood urinary tract infection in primary care: a prospective observational study of prevalence, diagnosis, treatment, and recovery.

BACKGROUND: The prevalence of targeted and serendipitous treatment for, and associated recovery from, urinary tract infection (UTI) in pre-school children is unknown. AIM: To determine the frequency and suspicion of UTI in children who are acutely ill, along with details of antibiotic prescribing, its appropriateness, and whether that appropriateness impacted on symptom improvement and recovery. DESIGN AND SETTING: Prospective observational cohort study in primary care sites in urban and rural areas in England and Wales. METHOD: Systematic urine sampling from children aged <5 years presenting in primary care with acute illness with culture in NHS laboratories. RESULTS: Of 6079 children's urine samples, 339 (5.6%) met laboratory criteria for UTI and 162 (47.9%) were prescribed antibiotics at the initial consultation. In total, 576/7101 (8.1%) children were suspected of having a UTI prior to urine sampling, including 107 of the 338 with a UTI (clinician sensitivity 31.7%). Children with a laboratory-diagnosed UTI were more likely to be prescribed antibiotics when UTI was clinically suspected than when it was not (86.0% versus 30.3%, P<0.001). Of 231 children with unsuspected UTI, 70 (30.3%) received serendipitous antibiotics (that is, antibiotics prescribed for a different reason). Overall, 176 (52.1%) children with confirmed UTI did not receive any initial antibiotic. Organism sensitivity to the prescribed antibiotic was higher when UTI was suspected than when treated serendipitously (77.1% versus 26.0%; P<0.001). Children with UTI prescribed appropriate antibiotics at the initial consultation improved a little sooner than those with a UTI who were not prescribed appropriate antibiotics initially (3.5 days versus 4.0 days; P = 0.005). CONCLUSION: Over half of children with UTI on culture were not prescribed antibiotics at first presentation. Serendipitous UTI treatment was relatively common, but often inappropriate to the organism's sensitivity. Methods for improved targeting of antibiotic treatment in children who are acutely unwell are urgently needed.

Point of care testing for urinary tract infection in primary care (POETIC): protocol for a randomised controlled trial of the clinical and cost effectiveness of FLEXICULT™ informed management of uncomplicated UTI in primary care.

BACKGROUND: Urinary tract infections (UTI) are the most frequent bacterial infection affecting women and account for about 15% of antibiotics prescribed in primary care. However, some women with a UTI are not prescribed antibiotics or are prescribed the wrong antibiotics, while many women who do not have a microbiologically confirmed UTI are prescribed antibiotics. Inappropriate antibiotic prescribing unnecessarily increases the risk of side effects and the development of antibiotic resistance, and wastes resources. METHODS/DESIGN: 614 adult female patients will be recruited from four primary care research networks (Wales, England, Spain, the Netherlands) and individually randomised to either POCT guided care or the guideline-informed 'standard care' arm. Urine and stool samples (where possible) will be obtained at presentation (day 1) and two weeks later for microbiological analysis. All participants will be followed up on the course of their illness and their quality of life, using a 2 week self-completed symptom diary. At 3 months, a primary care notes review will be conducted for evidence of further evidence of treatment failures, recurrence, complications, hospitalisations and health service costs. DISCUSSION: Although the Flexicult™ POCT is used in some countries in routine primary care, it's clinical and cost effectiveness has never been evaluated in a randomised clinical trial. If shown to be effective, the use of this POCT could benefit individual sufferers and provide evidence for health care authorities to develop evidence based policies to combat the spread and impact of the unprecedented rise of infections caused by antibiotic resistant bacteria in Europe. TRIAL REGISTRATION NUMBER: ISRCTN65200697 (Registered 10 September 2013).