Dipsticks and diagnostic algorithms in urinary tract infection: development and validation, randomised trial, economic analysis, observational cohort and qualitative study

Delayed and Non-Antibiotic Therapy for Urinary Tract Infections: A Literature Review

Urinary tract infections are among the most common infections encountered in the clinic and remain a top indication for women to receive antibiotics. Delayed antibiotic prescribing and non-antibiotic symptomatic therapies are treatment paradigms common to other uncomplicated infectious diseases, such as upper respiratory infections. We aimed to review the literature on delayed antibiotics and non-antibiotic treatments as alternatives to immediate antibiotic prescriptions for uncomplicated cystitis. A literature search was performed in PubMed, Google Scholar, and Web of Science to identify relevant clinical trials and reference lists of included articles were examined to find additional studies. All published trials where same day treatment with antibiotics was compared to scenarios where antibiotics were intentionally delayed or withheld or where antibiotics were compared to non-antimicrobial agents or placebo were analyzed. A total of 13 articles were included. Trials were grouped into categories based on their comparator groups: placebo (n = 5), delayed antibiotic therapy (n = 3), and symptomatic treatment (n = 5). Antibiotic delay and ibuprofen, while less effective than antibiotics in early microbiologic and clinical cure, may still be considered plausible alternatives to immediate antibiotic treatment in non-pregnant women with cystitis. Day 7 and later symptomatic resolution ranges from 26-75% with delayed or placebo therapy and 70-83% with nonsteroidal anti-inflammatory drugs. Symptom improvement, however, may be delayed compared to immediate antibiotics. These approaches have shown to decrease antibiotic use in primary care settings with low rates of pyelonephritis. Methodology included in these studies may be considered in stewardship interventions for outpatient clinics.

Treating urinary tract infections in the era of antibiotic resistance

INTRODUCTION

Urinary tract infections (UTIs) are associated with 25-40% of antibiotics consumed in primary care and are, therefore, driving antibiotic resistance. The worldwide increase in antibiotic resistance especially in Escherichia coli has complicated the treatment choices for UTIs and absence of effective oral antibiotics may lead to increasing need for more effective treatments.

AREAS COVERED

In this review we focus on the importance of the correct diagnosis of UTI as based on proof of urinary pathogens in the urine and discuss diagnostic measures including microscopy, dipstick, and culture. Antibiotic treatment can often await diagnostic measures with pain relief such as ibuprofen. The risk of an uncomplicated UTI leading to pyelonephritis is low (1-2%) and presence of bacteria in the bladder leaves some time for the immune system to react. Three antibiotics are recommended as based on their activity, and low propensity to select for resistance, i.e. nitrofurantoin, fosfomycin, and pivmecillinam, and in general, 3-5 days of treatment will suffice.

EXPERT OPINION

Understanding the usual benign course of uUTIs can help reduce antibiotic treatment in many cases, e.g. starting treatment by pain relief and awaiting the course of infection without antibiotics. Better rapid tests in primary care are urgently needed to enforce such policies.

Development, Evaluation, and Multisite Deployment of a Machine Learning Decision Tree Algorithm To Optimize Urinalysis Parameters for Predicting Urine Culture Positivity

PittUDT, a recursive partitioning decision tree algorithm for predicting urine culture (UC) positivity based on macroscopic and microscopic urinalysis (UA) parameters, was developed in support of a broader system-wide diagnostic stewardship initiative to increase appropriateness of UC testing. Reflex algorithm training utilized results from 19,511 paired UA and UC cases (26.8% UC positive); the average patient age was 57.4 years, and 70% of samples were from female patients. Receiver operating characteristic (ROC) analysis identified urine white blood cells (WBCs), leukocyte esterase, and bacteria as the best predictors of UC positivity, with areas under the ROC curve of 0.79, 0.78, and 0.77, respectively. Using the held-out test data set (9,773 cases; 26.3% UC positive), the PittUDT algorithm met the prespecified target of a negative predictive value above 90% and resulted in a 30 to 60% total negative proportion (true-negative plus false-negative predictions). These data show that a supervised rule-based machine learning algorithm trained on paired UA and UC data has adequate predictive ability for triaging urine specimens by identifying low-risk urine specimens, which are unlikely to grow pathogenic organisms, with a false-negative proportion under 5%. The decision tree approach also generates human-readable rules that can be easily implemented across multiple hospital sites and settings. Our work demonstrates how a data-driven approach can be used to optimize UA parameters for predicting UC positivity in a reflex protocol, with the intent of improving antimicrobial stewardship and UC utilization, a potential avenue for cost savings.

A semi-supervised decision support system to facilitate antibiotic stewardship for urinary tract infections

Urinary Tract Infections (UTIs) are among the most frequently occurring infections in the hospital. Urinalysis and urine culture are the main tools used for diagnosis. Whereas urinalysis is sufficiently sensitive for detecting UTI, it has a relatively low specificity, leading to unnecessary treatment with antibiotics and the risk of increasing antibiotic resistance. We performed an evaluation of the current diagnostic process with an expert-based label for UTI as outcome, retrospectively established using data from the Electronic Health Records. We found that the combination of urinalysis results with the Gram stain and other readily available parameters can be used effectively for predicting UTI. Based on the obtained information, we engineered a clinical decision support system (CDSS) using the reliable semi-supervised ensemble learning (RESSEL) method, and found it to be more accurate than urinalysis or the urine culture for prediction of UTI. The CDSS provides clinicians with this prediction within hours of ordering a culture and thereby enables them to hold off on prematurely prescribing antibiotics for UTI while awaiting the culture results.

Reducing antibiotic use in uncomplicated urinary tract infections in adult women: a systematic review and individual participant data meta-analysis

BACKGROUND

Randomised controlled trials (RCTs) investigated analgesics, herbal formulations, delayed prescription of antibiotics and placebo to prevent overprescription of antibiotics in women with uncomplicated urinary tract infections (uUTI).

OBJECTIVES

To estimate the effect of these strategies and to identify symptoms, signs or other factors that indicate a benefit from these strategies.

DATA SOURCES

MEDLINE, EMBASE, Web of Science, LILACS, Cochrane Database of Systematic Reviews and of Controlled Trials, and ClinicalTrials.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

RCTs investigating any strategies to reduce antibiotics versus immediate antibiotics in adult women with uUTI in primary care.

DATA SYNTHESIS

We extracted individual participant data (IPD) if available, otherwise aggregate data (AD). Bayesian random-effects meta-analysis of the AD was used for pairwise comparisons. Candidate moderators and prognostic indicators of treatment effects were investigated using generalised linear mixed models based on IPD.

RESULTS

We analysed IPD of 3524 patients from eight RCTs and AD of 78 patients. Non-antibiotic strategies increased the rates of incomplete recovery (odds ratio [OR] 3.0; 95% credible interval [CI] 1.7-5.5; Bayesian p-value p_B=0.0017; τ=0.6), subsequent antibiotic treatment (OR 3.5 [95% CI 2.1, 5.8; p_B=0.0003) and pyelonephritis (OR 5.6; 95% CI 2.3, 13.9; p_B=0.0003). Conversely, they decreased overall antibiotic use by 63%. In patients positive for urinary erythrocytes and urine culture were at increased risk for incomplete recovery (OR 4.7; 95% CI 2.1-10.8; p_B =0.0010), but no difference was apparent where both were negative (OR 0.8; 95% CI 0.3-2.0; p_B =0.667). In patients treated with using non-antibiotic strategies, urinary erythrocytes and positive urine culture were independent prognostic indicators for subsequent antibiotic treatment and pyelonephritis.

CONCLUSIONS AND RELEVANCE

Compared to immediate antibiotics, non-antibiotic strategies reduce overall antibiotic use but result in poorer clinical outcomes. The presence of erythrocytes and tests to confirm bacteria in urine could be used to target antibiotic prescribing.

Use and quality of point-of-care microscopy, urine culture and susceptibility testing for urinalysis in general practice

Objective: To describe the use and quality of point-of-care (POC) microscopy, urine culture and susceptibility testing performed in general practice in Northern Denmark from 2013 to 2018.Design: Descriptive studySetting: General practices receiving a fee for examining urine samples.Subjects: Simulated urine samples containing uropathogenic bacteria distributed by the organisation for improvement of microbiological quality (MIKAP).Main outcome measures: Percentage of use and correct answers for microscopy, culture and susceptibility testing.Results: A total of 5361 samples were analysed by the use of microscopy (39.7%), culture (66.0%) and/or susceptibility testing (76.5%). For culture, Flexicult SSI urinary kittm (87.6%) demonstrated the highest percentage of correct answers followed by chromogenic agar (85.1%) and 2-plate dipslide (85.2%). Mueller Hinton agar with tablets had the highest percentage of correct answers for susceptibility testing of most bacterial strains (84.6%), followed by Flexicult (77.2%). Furthermore, susceptibility testing with tablets (range: 76.1-84.6%) was found to be more accurate than discs (range: 72.9-75.5%). Overall, the highest percentage of correct answers was obtained when examining urine samples containing Escherichia coli: Microscopy (78.3%), culture (87.0%) and susceptibility testing (range: 84.3-90.7%).Conclusion: The quality of POC testing in general practice was high when examining urine samples containing the most common uropathogen E. coli. Surprisingly, susceptibility testing was more frequently used than culture. This approach may compromise the treatment decision as only cultures contribute with information about the flora composition and bacterial quantification. Interestingly, microscopy was the least used method even though the result may be reached within a few minutes.Key pointsThe quality of POC tests (microscopy, urine culture, susceptibility testing) performed in general practice was high when examining urine containing E. coli, whereas difficulties were observed for samples including S. saprophyticus or K. pneumoniae.Susceptibility testing was more often performed than urine culture, which indicates a problem as only urine cultures contribute with information about the flora composition and bacterial quantification.

Experiences of urinary tract infection: A systematic review and meta-ethnography

AIM

To understand the experience of urinary tract infection (UTI) by synthesizing primary qualitative research findings and developing a conceptual model that illustrates this experience.

METHOD

A systematic search of Medline, PsychInfo, Embase, and CINAHL from inception to August 2020 to find qualitative research exploring the experience of UTI. Qualitative evidence synthesis in the form of meta-ethnography was undertaken. Findings are reported in keeping with eMERGe guidance.

RESULTS

We included 16 qualitative studies in the synthesis of evidence, providing data from over 1038 participants aged 13-97 years. We developed nine themes: the impact of UTI on my whole body; impact on quality of life, activities, and the associated psychological toll; I know my body and my experience has taught me when I need to seek care; worry and the transition to medicalization; antibiotics are a valuable treatment approach; antibiotics are a last resort; being heard, seen, and cared for with dignity; self-judgment; and the end of the road, a need for information and cure. These themes supported a conceptual model to illustrate the patient experience of UTI.

CONCLUSIONS

The conceptual model communicates the wide and varied symptoms of patients' UTI experiences and how they process this and make care decision based on past health experiences. For some, there appears to be a sense of hopelessness and frustration. This model may be used to highlight the need for improvements in diagnostic and treatment pathways. Future research to further understand the nuances of acute, recurrent, and persistent UTI is needed.

Comprehensive review of statistical methods for analysing patient-reported outcomes (PROs) used as primary outcomes in randomised controlled trials (RCTs) published by the UK's Health Technology Assessment (HTA) journal (1997-2020)

OBJECTIVES

To identify how frequently patient-reported outcomes (PROs) are used as primary and/or secondary outcomes in randomised controlled trials (RCTs) and to summarise what statistical methods are used for the analysis of PROs.

DESIGN

Comprehensive review.

SETTING

RCTs funded and published by the United Kingdom's (UK) National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme.

DATA SOURCES AND ELIGIBILITY

HTA reports of RCTs published between January 1997 and December 2020 were reviewed.

DATA EXTRACTION

Information relating to PRO use and analysis methods was extracted.

PRIMARY AND SECONDARY OUTCOME MEASURES

The frequency of using PROs as primary and/or secondary outcomes; statistical methods that were used for the analysis of PROs as primary outcomes.

RESULTS

In this review, 37.6% (114/303) of trials used PROs as primary outcomes, and 82.8% (251/303) of trials used PROs as secondary outcomes from 303 NIHR HTA reports of RCTs. In the 114 RCTs where the PRO was the primary outcome, the most used PRO was the Short-Form 36 (8/114); the most popular methods for multivariable analysis were linear mixed model (45/114), linear regression (29/114) and analysis of covariance (13/114); logistic regression was applied for binary and ordinal outcomes in 14/114 trials; and the repeated measures analysis was used in 39/114 trials.

CONCLUSION

The majority of trials used PROs as primary and/or secondary outcomes. Conventional methods such as linear regression are widely used, despite the potential violation of their assumptions. In recent years, there is an increasing trend of using complex models (eg, with mixed effects). Statistical methods developed to address these violations when analysing PROs, such as beta-binomial regression, are not routinely used in practice. Future research will focus on evaluating available statistical methods for the analysis of PROs.

Presentation, Treatment, and Natural Course of Severe Symptoms of Urinary Tract Infections Measured by a Smartphone App: Observational and Feasibility Study

Background

Urinary tract infections (UTIs) are one of the most common conditions in women. Current information on the presentation, management, and natural course of the infection is based on paper diaries filled out and subsequently posted by patients.

Objective

The aim of this study is to explore the feasibility of a smartphone app to assess the natural course and management of UTIs.

Methods

A smartphone app was developed to collect data from study participants presenting with symptoms of UTI in general practice. After initial demographic and treatment information, symptom severity was recorded by the patient after a reminder on their smartphone, which occurred twice daily for a period of 7 days or until symptom resolution.

Results

A total of 181 women aged 18-76 years downloaded the smartphone app. The duration of symptoms was determined from the results of 178 participants. All patients submitted a urine sample, most patients were prescribed an antibiotic (163/181, 90.1%), and 38.7% (70/181) of the patients had a positive culture. Moderately bad or worse symptoms lasted a mean of 3.8 (SD 3.2; median 4) days, and 70.2% (125/178) of the patients indicated that they were cured on day 4 after consultation. This compares with other research assessing symptom duration and management of UTIs using paper diaries. Patients were very positive about the usability of the smartphone app and often found the reminders supportive. On the basis of the feedback and the analysis of the data, some suggestions for improvement were made.

Conclusions

Smartphone diaries for symptom scores over the course of infections are an efficient and acceptable means of collecting data in research.

Diarrhoea Management using Over-the-counter Nutraceuticals in Daily practice (DIAMOND): a feasibility RCT on alternative therapy to reduce antibiotic use

BACKGROUND

Although rarely indicated, antibiotics are commonly used for acute diarrhoea in China. We conducted a randomised, double blind exploratory clinical trial of loperamide, berberine and turmeric for treatment of acute diarrhoea.

METHODS

Adults with acute uncomplicated diarrhoea aged 18 to 70 were randomised to 4 groups: (A) loperamide; (B) loperamide and berberine; (C) loperamide and turmeric; (D) loperamide, berberine and turmeric. All participants were given rescue ciprofloxacin for use after 48 h if symptoms worsened or were unimproved. Primary endpoints were feasibility and ciprofloxacin use during the 2-week follow-up period. Semi-structured interviews were conducted following recruitment and were analysed thematically. Recruiting doctors, delivery pharmacists and research assistants were blinded to treatment allocation.

RESULTS

Only 21.5% (278/1295) of patients screened were deemed eligible, and 49% (136/278) of these consented and were entered into the final analysis. Most participants had mild symptoms, because most patients with moderate or severe symptoms wanted to be given antibiotics. Follow-up was good (94% at 2 weeks). Only three participants used rescue antibiotics compared to 67% of acute diarrhoea patients in the hospital during the recruitment period. The median symptom duration was 14 h in group B (interquartile range (IQR) 10-22), 16 h in group D (IQR 10-22), 18 h in group A (IQR 10-33) and 20 h in group C (IQR 16-54). Re-consultation rates were low. There were no serious treatment-related adverse events. Most interviewed participants said that although they had believed antibiotics to be effective for diarrhoea, they were surprised by their quick recovery without antibiotics in this trial.

CONCLUSION

Although recruitment was challenging because of widespread expectations for antibiotics, patients with mild diarrhoea accepted trying an alternative. The three nutraceuticals therapy require further evaluation in a fully powered, randomised controlled trial among a broader sample.

TRIAL REGISTRATION

ChiCTR-IPR-17014107.

Rapid uropathogen identification using surface enhanced Raman spectroscopy active filters

Urinary tract infection is one of the most common bacterial infections leading to increased morbidity, mortality and societal costs. Current diagnostics exacerbate this problem due to an inability to provide timely pathogen identification. Surface enhanced Raman spectroscopy (SERS) has the potential to overcome these issues by providing immediate bacterial classification. To date, achieving accurate classification has required technically complicated processes to capture pathogens, which has precluded the integration of SERS into rapid diagnostics. This work demonstrates that gold-coated membrane filters capture and aggregate bacteria, separating them from urine, while also providing Raman signal enhancement. An optimal gold coating thickness of 50 nm was demonstrated, and the diagnostic performance of the SERS-active filters was assessed using phantom urine infection samples at clinically relevant concentrations (10⁵ CFU/ml). Infected and uninfected (control) samples were identified with an accuracy of 91.1%. Amongst infected samples only, classification of three bacteria (Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae) was achieved at a rate of 91.6%.

Impact of Obesity on Urinary Tract Infections in Korean Adults: Secondary Data Analysis Using Community-Based Cohort Study

PURPOSE

This study investigated the incidence of urinary tract infection (UTI) in community-dwelling adults and identified the association between obesity and UTI.

METHODS

The participants were 4,926 adults aged over 40 years who had no UTIs at the baseline survey of the Korean Genome Epidemiology Study. Obesity was defined according to the cirtieria of Korean Society for the Study of Obesity using body mass index (BMI) data. UTI was defined as those who had self-reported UTI or had either nitrite, or both leukocytes and blood in the urine dipstick test. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using a multivariate Cox proportional hazards regression analysis to identify the association between the obesity and UTI.

RESULTS

The incidence proportion of UTI was 5.1%, and the incidence density per 1,000 person-years was 25.5. After controlling general characteristics, people with BMI ≥30.0 kg/m² remained 1.66 times (HR = 1.66, 95% CI = 1.06~2.60; p < .05) more likely to have UTI than those with normal weight. This trend was also present in men or people aged ≥ 60 years. Among women aged ≥ 60 years, people with BMI ≥ 30.0 kg/m² were 1.98 times (HR = 1.98, 95% CI = 1.01~3.86; p < .05) more likely to have UTI than those with normal weight.

CONCLUSION

The BMI ≥ 30.0 kg/m² is a risk factor of UTIs in Korean adult men over 40 years and women aged ≥ 60 years. It is necessary to emphasize the importance of obesity management to men or women aged ≥ 60 years, specifically.

Cranberry Extract for Symptoms of Acute, Uncomplicated Urinary Tract Infection: A Systematic Review

BACKGROUND

Effective alternatives to antibiotics for alleviating symptoms of acute infections may be appealing to patients and enhance antimicrobial stewardship. Cranberry-based products are already in wide use for symptoms of acute urinary tract infection (UTI). The aim of this review was to identify and critically appraise the supporting evidence.

METHODS

The protocol was registered on PROSPERO. Searches were conducted of Medline, Embase, Amed, Cinahl, The Cochrane library, Clinicaltrials.gov and WHO International Clinical Trials Registry Platform. We included randomised clinical trials (RCTs) and non-randomised studies evaluating the effect of cranberry extract in the management of acute, uncomplicated UTI on symptoms, antibiotic use, microbiological assessment, biochemical assessment and adverse events. Study risk of bias assessments were made using Cochrane criteria.

RESULTS

We included three RCTs (n = 688) judged to be at moderate risk of bias. One RCT (n = 309) found that advice to consume cranberry juice had no statistically significant effect on UTI frequency symptoms (mean difference (MD) -0.01 (95% CI: -0.37 to 0.34), p = 0.94)), on UTI symptoms of feeling unwell (MD 0.02 (95% CI: -0.36 to 0.39), p = 0.93)) or on antibiotic use (odds ratio 1.27 (95% CI: 0.47 to 3.43), p = 0.64), when compared with promoting drinking water. One RCT (n = 319) found no symptomatic benefit from combining cranberry juice with immediate antibiotics for an acute UTI, compared with placebo juice combined with immediate antibiotics. In one RCT (n = 60), consumption of cranberry extract capsules was associated with a within-group improvement in urinary symptoms and Escherichia coli load at day 10 compared with baseline (p < 0.01), which was not found in untreated controls (p = 0.72). Two RCTs were under-powered to detect differences between groups for outcomes of interest. There were no serious adverse effects associated with cranberry consumption.

CONCLUSION

The current evidence base for or against the use of cranberry extract in the management of acute, uncomplicated UTIs is inadequate; rigorous trials are needed.

Strategies to reduce antibiotic use in women with uncomplicated urinary tract infection in primary care: protocol of a systematic review and meta-analysis including individual patient data

INTRODUCTION

Uncomplicated urinary tract infection (UTI) in women is a common reason to present in general practice and is usually treated with antibiotics to reduce symptom severity and duration. Results of recent clinical trials indicate that non-antibiotic treatment approaches can also be effective. However, it remains unclear which patients would benefit from antibiotic treatment and which can effectively and safely be treated without antibiotics. This systematic review and meta-analysis aims to estimate the effect of treatment strategies to reduce antibiotic use in comparison with immediate antibiotic treatment and to identify prognostic factors and moderators of treatment effects. A further aim is to identify subgroups of patients benefiting from a specific therapy.

METHODS AND ANALYSIS

A systematic literature search will be performed to identify randomised controlled trials which investigated the effect of treatment strategies to reduce antibiotic use in female adults with uncomplicated UTI compared with immediate antibiotic treatment. Therefore, the primary outcome of the meta-analysis is incomplete recovery. Anonymised individual patient data (IPD) will be collected. Aggregate data will be used for pairwise comparisons of treatment strategies using meta-analysis models with random effects accounting for potential between-study heterogeneity. Potential effect moderators will be explored in meta-regressions. For IPD, generalised linear mixed models will be used, which may be adjusted for baseline characteristics. Interactions of baseline variables with treatment effects will be explored. These models will be used to assess direct comparisons of treatment, but might be extended to networks.

ETHICS AND DISSEMINATION

The local institutional review and ethics board judged the project a secondary analysis of existing anonymous data which meet the criteria for waiver of ethics review. Dissemination of the results will be via published scientific papers and presentations. Key messages will be promoted for example, via social media or press releases.

PROSPERO REGISTRATION NUMBER

CRD42019125804.

Diagnosis and Management of UTI in Primary Care Settings-A Qualitative Study to Inform a Diagnostic Quick Reference Tool for Women Under 65 Years

Background: To inform interventions to improve antimicrobial use in urinary tract infections (UTIs) and contribute to a reduction in Escherichia coli bloodstream infection, we explored factors influencing the diagnosis and management of UTIs in primary care. Design: Semi-structured focus groups informed by the Theoretical Domains Framework. Setting: General practice (GP) surgeries in two English clinical commissioning groups (CCGs), June 2017 to March 2018. Participants: A total of 57 GP staff within 8 focus groups. Results: Staff were very aware of common UTI symptoms and nitrofurantoin as first-line treatment, but some were less aware about when to send a urine culture, second-line and non-antibiotic management, and did not probe for signs and symptoms to specifically exclude vaginal causes or pyelonephritis before prescribing. Many consultations were undertaken over the phone, many by nurse practitioners, and followed established protocols that often included urine dipsticks and receptionists. Patient expectations increased use of urine dipsticks, and immediate and 5 days courses of antibiotics. Management decisions were also influenced by patient co-morbidities. No participants had undertaken recent UTI audits. Patient discussions around antibiotic resistance and back-up antibiotics were uncommon compared to consultations for respiratory infections. Conclusions: Knowledge and skill gaps could be addressed with education and clear, accessible, UTI diagnostic and management guidance and protocols that are also appropriate for phone consultations. Public antibiotic campaigns and patient-facing information should cover UTIs, non-pharmaceutical recommendations for "self-care", prevention and rationale for 3 days antibiotic courses. Practices should be encouraged to audit UTI management.

Is Non-Steroidal Anti-Inflammatory Therapy Non-Inferior to Antibiotic Therapy in Uncomplicated Urinary Tract Infections: a Systematic Review

BACKGROUND

Amid growing antimicrobial resistance, there is an increasing focus on antibiotic stewardship efforts to reduce inappropriate antibiotic prescribing. In this context, novel approaches for treating infections without antibiotics are being explored. One such strategy is the use of non-steroidal anti-inflammatory drugs (NSAIDs) for uncomplicated urinary tract infections (UTIs). Therefore, we conducted a systematic review of randomized controlled trials to evaluate the rates of symptom resolution and infectious complications in adult women with uncomplicated UTIs treated with antibiotics versus NSAIDs.

METHODS

We systematically searched PubMed, CINHAL, Scopus, Web of Science Core Collection, EMBASE, and ClinicalTrials.gov from inception until January 13, 2020, for randomized controlled trials comparing NSAIDs with antibiotics for treatment of uncomplicated UTIs in adult women. Studies comparing symptom resolution between groups were eligible. Two authors screened all studies independently and in duplicate; data were abstracted using a standardized template. Risk of bias was assessed using the Cochrane Collaboration tool.

RESULTS

Five randomized trials that included 1309 women with uncomplicated UTI met inclusion criteria. Three studies (1130 patients) favored antibiotic therapy in terms of symptom resolution. Two studies (179 patients) found no difference between NSAIDs and antibiotics in terms of symptom resolution. Three studies reported rates of pyelonephritis, two of which found higher rates in patients treated with NSAIDs versus antibiotics. Between two studies that reported this outcome (747 patients), patients randomized to NSAIDs received fewer antibiotic prescriptions compared with those in the antibiotics group. Three studies were at low risk of bias, one had an unclear risk of bias, and one was at high risk of bias.

DISCUSSION

For the outcomes of symptom resolution and complications in adult women with UTI, evidence favors antibiotics over NSAIDs.

PROSPERO

CRD42018114133.

Identification of clinical and urine biomarkers for uncomplicated urinary tract infection using machine learning algorithms

Women with uncomplicated urinary tract infection (UTI) symptoms are commonly treated with empirical antibiotics, resulting in overuse of antibiotics, which promotes antimicrobial resistance. Available diagnostic tools are either not cost-effective or diagnostically sub-optimal. Here, we identified clinical and urinary immunological predictors for UTI diagnosis. We explored 17 clinical and 42 immunological potential predictors for bacterial culture among women with uncomplicated UTI symptoms using random forest or support vector machine coupled with recursive feature elimination. Urine cloudiness was the best performing clinical predictor to rule out (negative likelihood ratio [LR−] = 0.4) and rule in (LR+ = 2.6) UTI. Using a more discriminatory scale to assess cloudiness (turbidity) increased the accuracy of UTI prediction further (LR+ = 4.4). Urinary levels of MMP9, NGAL, CXCL8 and IL-1β together had a higher LR+ (6.1) and similar LR− (0.4), compared to cloudiness. Varying the bacterial count thresholds for urine culture positivity did not alter best clinical predictor selection, but did affect the number of immunological predictors required for reaching an optimal prediction. We conclude that urine cloudiness is particularly helpful in ruling out negative UTI cases. The identified urinary biomarkers could be used to develop a point of care test for UTI but require further validation.

Validity of microscopy for diagnosing urinary tract infection in general practice - a systematic review

Objective: To investigate the validity of microscopy as a diagnostic tool for urinary tract infection in general practice. Methods: (Design/setting) A systematic review was conducted by searching Medline for clinical studies made in general practice, outpatient clinics or similar settings in which the accuracy/validity of microscopy was evaluated with urine culture as the reference standard. Results: Our search resulted in 108 titles. 28 potentially eligible studies were retrieved for full-text reading. We included eight studies involving 4582 patients in this review. The quality of the studies was moderate to high. Specificity ranged from 27% to 100%, sensitivity from 47% to 97%. The variation between studies did not allow for meta-analysis. Conclusion: We did not find substantial evidence to determine the clinical validity of microscopy performed in general practice on urine samples from patients with symptoms of UTI. Key points Urinary tract infection is common in general practice. Methods for precise diagnosis are needed in order to avoid inappropriate treatment. Currently no evidence-based consensus exists regarding the use of urinary microscopy in general practice. We did not find substantial evidence to determine the overall clinical validity of microscopy performed in general practice on urine samples from patients with symptoms of UTI. Light microscopy with oil immersion had high sensitivity and specificity but is time-consuming. Phase-contrast microscopy is quick and had high specificity but lower sensitivity.

Models and applications for measuring the impact of health research: update of a systematic review for the Health Technology Assessment programme

BACKGROUND

This report reviews approaches and tools for measuring the impact of research programmes, building on, and extending, a 2007 review.

OBJECTIVES

(1) To identify the range of theoretical models and empirical approaches for measuring the impact of health research programmes; (2) to develop a taxonomy of models and approaches; (3) to summarise the evidence on the application and use of these models; and (4) to evaluate the different options for the Health Technology Assessment (HTA) programme.

DATA SOURCES

We searched databases including Ovid MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature and The Cochrane Library from January 2005 to August 2014.

REVIEW METHODS

This narrative systematic literature review comprised an update, extension and analysis/discussion. We systematically searched eight databases, supplemented by personal knowledge, in August 2014 through to March 2015.

RESULTS

The literature on impact assessment has much expanded. The Payback Framework, with adaptations, remains the most widely used approach. It draws on different philosophical traditions, enhancing an underlying logic model with an interpretative case study element and attention to context. Besides the logic model, other ideal type approaches included constructionist, realist, critical and performative. Most models in practice drew pragmatically on elements of several ideal types. Monetisation of impact, an increasingly popular approach, shows a high return from research but relies heavily on assumptions about the extent to which health gains depend on research. Despite usually requiring systematic reviews before funding trials, the HTA programme does not routinely examine the impact of those trials on subsequent systematic reviews. The York/Patient-Centered Outcomes Research Institute and the Grading of Recommendations Assessment, Development and Evaluation toolkits provide ways of assessing such impact, but need to be evaluated. The literature, as reviewed here, provides very few instances of a randomised trial playing a major role in stopping the use of a new technology. The few trials funded by the HTA programme that may have played such a role were outliers.

DISCUSSION

The findings of this review support the continued use of the Payback Framework by the HTA programme. Changes in the structure of the NHS, the development of NHS England and changes in the National Institute for Health and Care Excellence's remit pose new challenges for identifying and meeting current and future research needs. Future assessments of the impact of the HTA programme will have to take account of wider changes, especially as the Research Excellence Framework (REF), which assesses the quality of universities' research, seems likely to continue to rely on case studies to measure impact. The HTA programme should consider how the format and selection of case studies might be improved to aid more systematic assessment. The selection of case studies, such as in the REF, but also more generally, tends to be biased towards high-impact rather than low-impact stories. Experience for other industries indicate that much can be learnt from the latter. The adoption of researchfish^® (researchfish Ltd, Cambridge, UK) by most major UK research funders has implications for future assessments of impact. Although the routine capture of indexed research publications has merit, the degree to which researchfish will succeed in collecting other, non-indexed outputs and activities remains to be established.

LIMITATIONS

There were limitations in how far we could address challenges that faced us as we extended the focus beyond that of the 2007 review, and well beyond a narrow focus just on the HTA programme.

CONCLUSIONS

Research funders can benefit from continuing to monitor and evaluate the impacts of the studies they fund. They should also review the contribution of case studies and expand work on linking trials to meta-analyses and to guidelines.

FUNDING

The National Institute for Health Research HTA programme.

Probiotic capsules and xylitol chewing gum to manage symptoms of pharyngitis: a randomized controlled factorial trial

BACKGROUND

Reducing the use of antibiotics for upper respiratory tract infections is needed to limit the global threat of antibiotic resistance. We estimated the effectiveness of probiotics and xylitol for the management of pharyngitis.

METHODS

In this parallel-group factorial randomized controlled trial, participants in primary care (aged 3 years or older) with pharyngitis underwent randomization by nurses who provided sequential intervention packs. Pack contents for 3 kinds of material and advice were previously determined by computer-generated random numbers: no chewing gum, xylitol-based chewing gum (15% xylitol; 5 pieces daily) and sorbitol gum (5 pieces daily). Half of each group were also randomly assigned to receive either probiotic capsules (containing 24 × 10⁹ colony-forming units of lactobacilli and bifidobacteria) or placebo. The primary outcome was mean self-reported severity of sore throat and difficulty swallowing (scale 0-6) in the first 3 days. We used multiple imputation to avoid the assumption that data were missing completely at random.

RESULTS

A total of 1009 individuals consented, 934 completed the baseline assessment, and 689 provided complete data for the primary outcome. Probiotics were not effective in reducing the severity of symptoms: mean severity scores 2.75 with no probiotic and 2.78 with probiotic (adjusted difference -0.001, 95% confidence interval [CI] -0.24 to 0.24). Chewing gum was also ineffective: mean severity scores 2.73 without gum, 2.72 with sorbitol gum (adjusted difference 0.07, 95% CI -0.23 to 0.37) and 2.73 with xylitol gum (adjusted difference 0.01, 95% CI -0.29 to 0.30). None of the secondary outcomes differed significantly between groups, and no harms were reported.

INTERPRETATION

Neither probiotics nor advice to chew xylitol-based chewing gum was effective for managing pharyngitis. Trial registration: ISRCTN, no. ISRCTN51472596.

Symptomatic treatment of uncomplicated lower urinary tract infections in the ambulatory setting: randomised, double blind trial

Objective To investigate whether symptomatic treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is non-inferior to antibiotics in the treatment of uncomplicated lower urinary tract infection (UTI) in women, thus offering an opportunity to reduce antibiotic use in ambulatory care.Design Randomised, double blind, non-inferiority trial.Setting 17 general practices in Switzerland.Participants 253 women with uncomplicated lower UTI were randomly assigned 1:1 to symptomatic treatment with the NSAID diclofenac (n=133) or antibiotic treatment with norfloxacin (n=120). The randomisation sequence was computer generated, stratified by practice, blocked, and concealed using sealed, sequentially numbered drug containers.Main outcome measures The primary outcome was resolution of symptoms at day 3 (72 hours after randomisation and 12 hours after intake of the last study drug). The prespecified principal secondary outcome was the use of any antibiotic (including norfloxacin and fosfomycin as trial drugs) up to day 30. Analysis was by intention to treat.Results 72/133 (54%) women assigned to diclofenac and 96/120 (80%) assigned to norfloxacin experienced symptom resolution at day 3 (risk difference 27%, 95% confidence interval 15% to 38%, P=0.98 for non-inferiority, P<0.001 for superiority). The median time until resolution of symptoms was four days in the diclofenac group and two days in the norfloxacin group. A total of 82 (62%) women in the diclofenac group and 118 (98%) in the norfloxacin group used antibiotics up to day 30 (risk difference 37%, 28% to 46%, P<0.001 for superiority). Six women in the diclofenac group (5%) but none in the norfloxacin group received a clinical diagnosis of pyelonephritis (P=0.03).Conclusion Diclofenac is inferior to norfloxacin for symptom relief of UTI and is likely to be associated with an increased risk of pyelonephritis, even though it reduces antibiotic use in women with uncomplicated lower UTI.Trial registration ClinicalTrials.gov NCT01039545.

Cost-effectiveness of antibiotic treatment of uncomplicated urinary tract infection in women: a comparison of four antibiotics

Background

Urinary tract infections (UTIs) are one of the most common reasons for women to attend primary care. There are four different antibiotics currently recommended in England for treatment of uncomplicated UTI but little evidence on their comparative cost-effectiveness.

Aim

To assess the relative cost-effectiveness of the four antibiotics currently recommended in England for treatment of uncomplicated UTI in adult women.

Design & setting

A cost-effectiveness model in adult women with signs and symptoms of uncomplicated UTI in primary care in England treated with fosfomycin, nitrofurantoin, pivmecillinam, or trimethoprim.

Method

A decision tree economic model of the treatment pathway encompassed up to two rounds of treatment, accounting for different resistance levels. End points included recovery, persistence, pyelonephritis, and/or hospitalisation. Prescription, primary and secondary care treatment, and diagnostic testing costs were aggregated. Cost-effectiveness was assessed as cost per UTI resolved.

Results

Trimethoprim 200 mg twice daily (for 3 or 7 days) was estimated to be the most cost-effective treatment (£70 per UTI resolved) when resistance was <30%. However, if resistance to trimethoprim was ≥30%, fosfomycin 3 g once became more cost-effective; at resistance levels of ≥35% for trimethoprim, both fosfomycin 3 g once and nitrofurantoin 100 mg twice daily for 7 days were shown to be more cost-effective.

Conclusion

Knowing local resistance levels is key to effective and cost-effective empirical prescribing. Recent estimates of trimethoprim resistance rates are close to 50%, in which case a single 3 g dose of fosfomycin is likely to be the most cost-effective treatment option.

Uva-ursi extract and ibuprofen as alternative treatments of adult female urinary tract infection (ATAFUTI): study protocol for a randomised controlled trial

BACKGROUND

Women with acute uncomplicated urine infection are usually treated with antibiotics. One trial has demonstrated that delayed antibiotic treatment offered without symptom relief results in a modest reduction in antibiotic use. There is some evidence that ibuprofen provides symptom relief and reduces antibiotic use. Uva-ursi, a herbal product, has a traditional use for urinary infection symptom relief. We set out to test: in adult women with suspected UTI who accept the delayed prescription strategy: Do NSAIDs or uva-ursi (a herbal product) provide relief from urinary symptoms and reduce antibiotic use.

METHODS/DESIGN

Adult women with suspected urinary tract infection presenting to primary care will be randomised using a factorial trial design in which patients will be randomised to one of two interventions as below: Group 1 - Uva-ursi + advice to take ibuprofen Group 2 - Placebo + advice to take ibuprofen Group 3 - Uva-ursi + no advice to take ibuprofen Group 4 - Placebo + no advice to take ibuprofen Patients and physicians will be blinded to the randomised group for the herb. The main outcome is symptom severity at days 2-4 recorded in a validated, self-report diary used in previous studies. Secondary outcomes include antibiotic use and symptom duration. In total the trial will require 328 patients in order to achieve at least 90% power for the primary endpoint and 80% for the secondary endpoint. In accordance with CONSORT guidelines all comparative analyses will be conducted on an intention-to-treat basis using SPSS or similar package.

DISCUSSION

The outcomes from this trial have the potential to modify the current approach to the management of acute urinary symptoms with less dependence on the use of antibiotics.

TRIAL REGISTRATION

ISRCTN registry, ID: ISRCTN43397016 . Registered on 11 February 2015.

Performance of the dipstick screening test as a predictor of negative urine culture

Objective

To investigate whether the urine dipstick screening test can be used to predict urine culture results.

Methods

A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed.

Results

The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively).

Conclusion

A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture.

Implications of Antibiotic Resistance for Patients' Recovery From Common Infections in the Community: A Systematic Review and Meta-analysis

BACKGROUND

Antibiotic use is the main driver for carriage of antibiotic-resistant bacteria. The perception exists that failure of antibiotic treatment due to antibiotic resistance has little clinical impact in the community.

METHODS

We searched MEDLINE, EMBASE, PubMed, Cochrane Central Register of Controlled Trials, and Web of Science from inception to 15 April 2016 without language restriction. We included studies conducted in community settings that reported patient-level data on laboratory-confirmed infections (respiratory tract, urinary tract, skin or soft tissue), antibiotic resistance, and clinical outcomes. Our primary outcome was clinical response failure. Secondary outcomes were reconsultation, further antibiotic prescriptions, symptom duration, and symptom severity. Where possible, we calculated odds ratios with 95% confidence intervals by performing meta-analysis using random effects models.

RESULTS

We included 26 studies (5659 participants). Clinical response failure was significantly more likely in participants with antibiotic-resistant Escherichia coli urinary tract infections (odds ratio [OR] = 4.19; 95% confidence interval [CI] = 3.27-5.37; n = 2432 participants), Streptococcus pneumoniae otitis media (OR = 2.51; 95% CI = 1.29-4.88; n = 921 participants), and S. pneumoniae community-acquired pneumonia (OR = 2.15; 95% CI = 1.32-3.51; n = 916 participants). Clinical heterogeneity precluded primary outcome meta-analysis for Staphylococcus aureus skin or soft-tissue infections.

CONCLUSIONS

Antibiotic resistance significantly impacts on patients' illness burden in the community. Patients with laboratory-confirmed antibiotic-resistant urinary and respiratory-tract infections are more likely to experience delays in clinical recovery after treatment with antibiotics. A better grasp of the risk of antibiotic resistance on outcomes that matter to patients should inform more meaningful discussions between healthcare professionals and patients about antibiotic treatment for common infections.

New markers of urinary tract infection

Urinary tract infection (UTI) is the most common bacterial infection independent of age. It is also one of the most common causes of hospitalizations for infections among elderly people and the most common indication for antibiotic prescriptions in primary care. Both diagnostics and management of lower and upper urinary tract infections provide challenges in clinical practice due to their high prevalence and recurrence, and worldwide increase of antibiotic resistance. The clinical symptoms of UTI are often uncharacteristic or asymptomatic. The accurate diagnosis and early treatment are crucial due to risk of septicaemia and long-term consequences. Currently the diagnosis of urinary tract infection is based on the presence of clinical symptoms in combination with the results of nitrite strip test indicating the presence of bacteria in urine and semi-quantitative measurement of white blood cells count in urine. Although urine culture is the gold standard in UTI diagnostics it is both time-consuming and costly. Searching for novel biomarkers of UTI has attracted much attention in recent years. The article reviews several promising serum and urine biomarkers of UTI such as leukocyte esterase, C-reactive protein, procalcitonin, interleukins, elastase alpha (1)-proteinase inhibitor, lactofferin, secretory immunoglobulin A, heparin-binding protein, xanthine oxidase, myeloperoxidase, soluble triggering receptor expressed on myeloid cells-1, α-1 microglobulin (α1Mg) and tetrazolium nitroblue test (TNB).

High risk of lower urinary tract symptoms in patients with irritable bowel syndrome

BACKGROUND

The aim of the present study was to investigate the prevalence of urinary tract infection (UTI) and the risk of lower urinary tract symptoms (LUTS) in women with irritable bowel syndrome (IBS) (including each subtype: constipation, diarrhea, and mixed) compared to women in the general population.

METHODS

Between January 2014 and December 2015, consecutive adult female patients diagnosed with IBS at the outpatient clinic of the University of Salerno and healthy women with regular bowel habits were enrolled in the study. At baseline, we checked for UTI with a dipstick test and questioned patients about the presence of LUTS in the previous 24 h.

RESULTS

We enrolled 141 IBS patients and 91 healthy controls in the study. There was no difference in the prevalence of UTI between IBS patients and healthy controls (4.9 vs 3.3%, p = 0.5). When we excluded patients with UTI, we found a 2.79 higher risk of increased urinary frequency [odds ratio (OR) 2.79, 95% confidence interval (CI) 1.37-5.68], a 2.68 higher risk of urinary urgency (OR 2.68, 95% CI 1.04-6.91), and more than three times the risk of having dysuria (OR 3.25, 95% CI 1.06-9.97) in IBS women compared to healthy controls. The risk of having at least one urinary symptom was independent of IBS subtype and IBS severity.

CONCLUSIONS

Our study shows that IBS women have a similar risk of UTI compared to healthy women even if they complain more of LUTS, independently of IBS subtype and severity.

Evidence synthesis to inform model-based cost-effectiveness evaluations of diagnostic tests: a methodological review of health technology assessments

BACKGROUND

Evaluations of diagnostic tests are challenging because of the indirect nature of their impact on patient outcomes. Model-based health economic evaluations of tests allow different types of evidence from various sources to be incorporated and enable cost-effectiveness estimates to be made beyond the duration of available study data. To parameterize a health-economic model fully, all the ways a test impacts on patient health must be quantified, including but not limited to diagnostic test accuracy.

METHODS

We assessed all UK NIHR HTA reports published May 2009-July 2015. Reports were included if they evaluated a diagnostic test, included a model-based health economic evaluation and included a systematic review and meta-analysis of test accuracy. From each eligible report we extracted information on the following topics: 1) what evidence aside from test accuracy was searched for and synthesised, 2) which methods were used to synthesise test accuracy evidence and how did the results inform the economic model, 3) how/whether threshold effects were explored, 4) how the potential dependency between multiple tests in a pathway was accounted for, and 5) for evaluations of tests targeted at the primary care setting, how evidence from differing healthcare settings was incorporated.

RESULTS

The bivariate or HSROC model was implemented in 20/22 reports that met all inclusion criteria. Test accuracy data for health economic modelling was obtained from meta-analyses completely in four reports, partially in fourteen reports and not at all in four reports. Only 2/7 reports that used a quantitative test gave clear threshold recommendations. All 22 reports explored the effect of uncertainty in accuracy parameters but most of those that used multiple tests did not allow for dependence between test results. 7/22 tests were potentially suitable for primary care but the majority found limited evidence on test accuracy in primary care settings.

CONCLUSIONS

The uptake of appropriate meta-analysis methods for synthesising evidence on diagnostic test accuracy in UK NIHR HTAs has improved in recent years. Future research should focus on other evidence requirements for cost-effectiveness assessment, threshold effects for quantitative tests and the impact of multiple diagnostic tests.

Survival After Suspected Urinary Tract Infection in Individuals with Advanced Dementia

OBJECTIVES

To determine whether antimicrobial treatment for suspected urinary tract infections (UTIs) improves survival in nursing home residents with advanced dementia.

DESIGN

Prospective cohort study.

SETTING

Thirty-five nursing homes in Boston, Massachusetts.

PARTICIPANTS

Nursing home residents who experienced at least one suspected UTI over a 12-month period (N = 110); mean participant age 86.4 ± 6.2, 84% female.

MEASUREMENTS

Analyses were at the level of the UTI episode. Antimicrobial treatment for each suspected UTI was categorized as none, oral, intramuscular, or intravenous or hospitalization. Survival was calculated from the date of suspected UTI episode until death or last known follow-up date. Covariates included resident and episode characteristics. Cox proportional hazards regression was used to examine the association between treatment group and risk of death after adjusting for covariates.

RESULTS

Residents experienced 196 suspected UTIs over the follow-up period; 33% (n = 36) died during follow-up. There was no antimicrobial use for 25.0% of the 196 suspected UTIs, oral antimicrobial use in 59.7%; intramuscular antimicrobial use in 9.2%, and intravenous antimicrobial use or hospital transfer in 6.1%. After multivariable adjustment, antimicrobial treatment was not significantly associated with mortality (oral, adjusted hazard ratio for death (AHR) = 1.09, 95% confidence interval (CI) = 0.43-2.75; intramuscular, AHR = 0.66, 95% CI = 0.08-5.66; intravenous or hospitalization, AHR = 1.83, 95% CI = 0.44-7.60).

CONCLUSION

Although the majority of suspected UTIs that nursing home residents with advanced dementia experienced were treated with antimicrobials, treatment was not associated with survival.

Holm S, Ferry BM, Monsen TJ. High Diagnostic Accuracy of Nitrite Test Paired with Urine Sediment can Reduce Unnecessary Antibiotic Therapy

BACKGROUND

Urinary tract infections (UTIs) are common bacterial infections dominated by lower UTI in women (LUTIW). Symptoms only are insufficient for diagnosis and accordingly, near patient diagnostic tests confidently confirming significant bacteriuria are desirable. The nitrite test (NIT) has low sensitivity, while bacterial and leukocyte counts disjunctively paired in urine sediment microscopy (SED) have high sensitivity. Similar symptomatic cure rates are found post antibiotic vs. placebo therapy in patients with negative cultures. Consequently, prescription on symptoms only implies unnecessary antibiotic therapy.

AIMS

to evaluate the diagnostic outcomes of NIT, SED and NIT disjunctively paired with SED (NIT+SED) vs. urine culture, with special focus on bladder incubation time (BIT), and to assess if NIT+SED can reduce unnecessary antibiotic therapy.

METHODS

A diagnostic, primary care, multicentre study including 1070 women with symptoms suggestive of lower UTI.

RESULTS

Significant bacteriuria was found in 77%. The BIT highly influenced the diagnostic outcomes and the optimal duration was ≥4h with sensitivity of 66, 90 and 95% for NIT, SED and NIT+SED, respectively. SED performed only in NIT negative specimens could reduce unnecessary antibiotics by 10% vs. prescription on symptoms only. The number needed to test with SED to reduce one unnecessary antibiotic course was five patients at BIT ≥4h and six patients at ≤3h or overall.

CONCLUSION

The BIT highly influences the diagnostic outcomes with the highest accuracy of NIT+SED. Diagnosis of LUTIW with NIT+SED can reduce unnecessary antibiotic therapy and subsequently decrease antimicrobial resistance.

TRIAL REGISTRATION

The Swedish Medical Product Agency 1995 03 01:151:01783/94.

The role of point-of-care tests in antibiotic stewardship for urinary tract infections in a resource-limited setting on the Thailand-Myanmar border

Objective

Published literature from resource‐limited settings is infrequent, although urinary tract infections (UTI) are a common cause of outpatient presentation and antibiotic use. Point‐of‐care test (POCT) interpretation relates to antibiotic use and antibiotic resistance. We aimed to assess the diagnostic accuracy of POCT and their role in UTI antibiotic stewardship.

Methods

One‐year retrospective analysis in three clinics on the Thailand–Myanmar border of non‐pregnant adults presenting with urinary symptoms. POCT (urine dipstick and microscopy) were compared to culture with significant growth classified as pure growth of a single organism >10⁵ CFU/ml.

Results

In 247 patients, 82.6% female, the most common symptoms were dysuria (81.2%), suprapubic pain (67.8%) and urinary frequency (53.7%). After excluding contaminated samples, UTI was diagnosed in 52.4% (97/185); 71.1% (69/97) had a significant growth on culture, and >80% of these were Escherichia coli (20.9% produced extended‐spectrum β‐lactamase (ESBL)). Positive urine dipstick (leucocyte esterase ≥1 and/or nitrate positive) compared against positive microscopy (white blood cell >10/HPF, bacteria ≥1/HPF, epithelial cells <5/HPF) had a higher sensitivity (99% vs. 57%) but a lower specificity (47% vs. 89%), respectively. Combined POCT resulted in the best sensitivity (98%) and specificity (81%). Nearly one in ten patients received an antimicrobial to which the organism was not fully sensitive.

Conclusion

One rapid, cost‐effective POCT was too inaccurate to be used alone by healthcare workers, impeding antibiotic stewardship in a high ESBL setting. Appropriate prescribing is improved with concurrent use and concordant results of urine dipstick and microscopy.

Diagnosing and treating urinary tract infections in older people

Even though diagnosing and treating urinary tract infections (UTIs) in older people can be difficult, it is essential to prevent reduction in the patients' wellbeing. Near-patient testing can be useful, but guidelines on this discuss the use of urine dipstick testing and laboratory culture in some detail. In addition, there are significant differences in the management of males and females, those with recurrent infections, and those with catheters. Community nurses are well placed to assess and manage this common condition, implementing correct treatment and resolution, owing to the close relationships they cultivate with service users. This article discusses the diagnosis and management of UTIs in older people, highlighting the differentials and red flags that need to be addressed urgently.

Diagnosing inflammation and infection in the urinary system via proteomics

Background

Current methodology for the diagnosis of diseases in the urinary system includes patient symptomology, urine analysis and urine culture. Asymptomatic bacteriuria from urethral colonization or indwelling catheters, sample contamination from perineal or vaginal sources, and non-infectious inflammatory conditions can mimic UTIs, leading to uncertainty on medical treatment decisions.

Methods

Innovative shotgun metaproteomic methods were used to analyze urine sediments from 120 patients also subjected to conventional urinalysis for various clinical reasons including suspected UTIs. The proteomic data were simultaneously searched for the presence of microbial agents, inflammation, immune responses against pathogens, and evidence of urothelial tissue injury. Hierarchical clustering analysis was performed to identify host protein patterns discerning UTI from urethral colonization and vaginal contamination of urine samples.

Results

Organisms causing more than 98% of all UTIs and commensal microbes of the urogenital and perineal area were identified from 76 urine sediments with detection sensitivities estimated to be similar to urine culture. Proteomic data permitted a thorough evaluation of inflammatory and antimicrobial immune responses. Hierarchical clustering of the data revealed that high abundances of proteins from activated neutrophils were associated with pathogens in most cases, and correlated well with leukocyte esterase activities and leukocyte counts via microscopy. Proteomic data also allowed assessments of urothelial injury, by quantifying proteins highly expressed in red blood cells and contributing to the acute phase response. Lactobacillus and Gardnerella vaginalis were frequently identified suggesting urethral colonization and/or vaginal contamination of urine.

Conclusions

A metaproteomic approach of interest for routine urine clinical diagnostics is presented. As compared to urinalysis and urine culture methods, the data are derived from a single experiment for a given sample and provide additional insights into presence or absence of inflammatory responses and vaginal contamination of urine specimens.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0475-3) contains supplementary material, which is available to authorized users.

Urinary tract infections in patients with type 2 diabetes mellitus: review of prevalence, diagnosis, and management

Urinary tract infections are more common, more severe, and carry worse outcomes in patients with type 2 diabetes mellitus. They are also more often caused by resistant pathogens. Various impairments in the immune system, poor metabolic control, and incomplete bladder emptying due to autonomic neuropathy may all contribute to the enhanced risk of urinary tract infections in these patients. The new anti-diabetic sodium glucose cotransporter 2 inhibitors have not been found to significantly increase the risk of symptomatic urinary tract infections. Symptoms of urinary tract infection are similar to patients without diabetes, though some patients with diabetic neuropathy may have altered clinical signs. Treatment depends on several factors, including: presence of symptoms, severity of systemic symptoms, if infection is localized in the bladder or also involves the kidney, presence of urologic abnormalities, accompanying metabolic alterations, and renal function. There is no indication to treat diabetic patients with asymptomatic bacteriuria. Further studies are needed to improve the treatment of patients with type 2 diabetes and urinary tract infections.

PRImary care Streptococcal Management (PRISM) study: in vitro study, diagnostic cohorts and a pragmatic adaptive randomised controlled trial with nested qualitative study and cost-effectiveness study

BACKGROUND

Antibiotics are still prescribed to most patients attending primary care with acute sore throat, despite evidence that there is modest benefit overall from antibiotics. Targeting antibiotics using either clinical scoring methods or rapid antigen detection tests (RADTs) could help. However, there is debate about which groups of streptococci are important (particularly Lancefield groups C and G), and uncertainty about the variables that most clearly predict the presence of streptococci.

OBJECTIVE

This study aimed to compare clinical scores or RADTs with delayed antibiotic prescribing.

DESIGN

The study comprised a RADT in vitro study; two diagnostic cohorts to develop streptococcal scores (score 1; score 2); and, finally, an open pragmatic randomised controlled trial with nested qualitative and cost-effectiveness studies.

SETTING

The setting was UK primary care general practices.

PARTICIPANTS

Participants were patients aged ≥ 3 years with acute sore throat.

INTERVENTIONS

An internet program randomised patients to targeted antibiotic use according to (1) delayed antibiotics (control group), (2) clinical score or (3) RADT used according to clinical score.

MAIN OUTCOME MEASURES

The main outcome measures were self-reported antibiotic use and symptom duration and severity on seven-point Likert scales (primary outcome: mean sore throat/difficulty swallowing score in the first 2-4 days).

RESULTS

The IMI TestPack Plus Strep A (Inverness Medical, Bedford, UK) was sensitive, specific and easy to use. Lancefield group A/C/G streptococci were found in 40% of cohort 2 and 34% of cohort 1. A five-point score predicting the presence of A/C/G streptococci [FeverPAIN: Fever; Purulence; Attend rapidly (≤ 3 days); severe Inflammation; and No cough or coryza] had moderate predictive value (bootstrapped estimates of area under receiver operating characteristic curve: 0.73 cohort 1, 0.71 cohort 2) and identified a substantial number of participants at low risk of streptococcal infection. In total, 38% of cohort 1 and 36% of cohort 2 scored ≤ 1 for FeverPAIN, associated with streptococcal percentages of 13% and 18%, respectively. In an adaptive trial design, the preliminary score (score 1; n = 1129) was replaced by FeverPAIN (n = 631). For score 1, there were no significant differences between groups. For FeverPAIN, symptom severity was documented in 80% of patients, and was lower in the clinical score group than in the delayed prescribing group (-0.33; 95% confidence interval -0.64 to -0.02; p = 0.039; equivalent to one in three rating sore throat a slight rather than moderately bad problem), and a similar reduction was observed for the RADT group (-0.30; -0.61 to 0.00; p = 0.053). Moderately bad or worse symptoms resolved significantly faster (30%) in the clinical score group (hazard ratio 1.30; 1.03 to 1.63) but not the RADT group (1.11; 0.88 to 1.40). In the delayed group, 75/164 (46%) used antibiotics, and 29% fewer used antibiotics in the clinical score group (risk ratio 0.71; 0.50 to 0.95; p = 0.018) and 27% fewer in the RADT group (0.73; 0.52 to 0.98; p = 0.033). No significant differences in complications or reconsultations were found. The clinical score group dominated both other groups for both the cost/quality-adjusted life-years and cost/change in symptom severity analyses, being both less costly and more effective, and cost-effectiveness acceptability curves indicated the clinical score to be the most likely to be cost-effective from an NHS perspective. Patients were positive about RADTs. Health professionals' concerns about test validity, the time the test took and medicalising self-limiting illness lessened after using the tests. For both RADTs and clinical scores, there were tensions with established clinical experience.

CONCLUSIONS

Targeting antibiotics using a clinical score (FeverPAIN) efficiently improves symptoms and reduces antibiotic use. RADTs used in combination with FeverPAIN provide no clear advantages over FeverPAIN alone, and RADTs are unlikely to be incorporated into practice until health professionals' concerns are met and they have experience of using them. Clinical scores also face barriers related to clinicians' perceptions of their utility in the face of experience. This study has demonstrated the limitation of using one data set to develop a clinical score. FeverPAIN, derived from two data sets, appears to be valid and its use improves outcomes, but diagnostic studies to confirm the validity of FeverPAIN in other data sets and settings are needed. Experienced clinicians need to identify barriers to the use of clinical scoring methods. Implementation studies that address perceived barriers in the use of FeverPAIN are needed.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN32027234.

SOURCE OF FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 6. See the NIHR Journals Library website for further project information.

Heparin-binding protein: a diagnostic biomarker of urinary tract infection in adults

Background.

 Urinary tract infections (UTIs) are associated with significant morbidity and high frequency of antibiotic prescription. Diagnosing UTI is often difficult, particularly in the critically ill patient and in patients with unspecific and mild symptoms. The standard rapid tests have limited value, and there is a need for more reliable diagnostic tools. Heparin-binding protein (HBP) is released from neutrophils and has previously been studied as a diagnostic and predictive biomarker in different bacterial infections.

Methods.

 This prospective survey enrolled adult patients at 2 primary care units and 2 hospital emergency departments, to investigate in urine HBP as a biomarker of UTI. In addition, urine levels of interleukin-6, white blood cells, and nitrite were analyzed and compared with HBP. Based on symptoms of UTI and microbiological findings, patients were classified into different groups, UTI (cystitis and pyelonephritis) and no UTI.

Results.

 Three hundred ninety patients were evaluated. The prevalence of UTI in the study group was 45.4%. The sensitivity and specificity for HBP in urine as a marker for UTI were 89.2% and 89.8%, respectively. The positive and negative predictive values were 90.2% and 88.8%, respectively. Heparin-binding protein was the best diagnostic marker for UTI, with an area-under-curve value of 0.94 (95% confidence interval, 0.93–0.96). Heparin-binding protein was significantly better in distinguishing cystitis from pyelonephritis, compared with the other markers.

Conclusions.

 An elevated level of HBP in the urine is associated with UTI and may be a useful diagnostic marker in adult patients with a suspected UTI.

Antibiotic treatment of urinary tract infection by community pharmacists: a cross-sectional study

BACKGROUND

Urinary tract infections (UTIs) are one of the most common conditions seen in female patients within primary care. Community pharmacists are familiar with symptomatic UTI management and supplying trimethoprim under patient group direction (PGD) for moderate-to-severe uncomplicated UTIs could improve patient access to treatment.

AIM

To compare the care pathway of patients with UTI symptoms attending GP services with those receiving management, including trimethoprim supply under PGD, via community pharmacies.

DESIGN AND SETTING

Prospective, cross-sectional, mixed methods approach in 10 community pharmacies within NHS Greater Glasgow and Clyde.

METHOD

Pharmacies invited a purposive sample of female patients to participate. Pharmacists had the option of supplying trimethoprim under PGD to patients with moderate-to-severe infection meeting the PGD inclusion criteria. Data from patient (questionnaires and semi-structured telephone interviews) and pharmacist (questionnaires and semi-structured, face-to-face interviews) were quantitatively and qualitatively analysed.

RESULTS

Data were recorded on 153 patients, 97 presenting with GP prescriptions and 56 presenting directly in the pharmacy with symptoms suggestive of UTI, of whom 41 received trimethoprim via PGD and 15 received symptomatic management. Both GP adherence to local infection management guidelines and pharmacist application of PGD inclusion/exclusion criteria required improvement. There was demand and support, from patients and pharmacists, for access to antibiotic treatments for UTIs, without prescription, through community pharmacies.

CONCLUSION

Operating within PGD controls, antibiotic treatments for UTIs could be provided via community pharmacy to improve patient access to treatment which may also maintain antibiotic stewardship and reduce GP workload.

Prevalence and predictors of antibiotic administration during pregnancy and birth

Background

Antibiotic treatment during pregnancy and birth is very common. In this study, we describe the estimated prevalence of antibiotic administration during pregnancy and birth in the COPSAC₂₀₁₀ pregnancy cohort, and analyze dependence on social and lifestyle-related factors.

Methods

706 pregnant women from the novel unselected Copenhagen Prospective Study on Asthma in Childhood (COPSAC₂₀₁₀) pregnancy cohort participated in this analysis. Detailed information on oral antibiotic prescriptions during pregnancy filled at the pharmacy was obtained and verified longitudinally. Information on intrapartum antibiotics, social, and lifestyle-factors was obtained by personal interviews.

Results

The prevalence of antibiotic use was 37% during pregnancy and 33% intrapartum. Lower maternal age at birth; adjusted odds ratio (aOR) 0.94, 95% CI, [0.90-0.98], p = 0.003 and maternal smoking; aOR 1.97, 95% CI, [1.07-3.63], p = 0.030 were associated with use of antibiotics for urinary tract infection during pregnancy. Maternal educational level (low vs. high), aOR 2.32, 95% CI, [1.24-4.35], p = 0.011, maternal asthma; aOR 1.99, 95% CI, [1.33-2.98], p < 0.001 and previous childbirth; aOR 1.80, 95% CI, [1.21-2.66], p = 0.004 were associated with use of antibiotics for respiratory tract infection during pregnancy. Lower gestational age; aOR 0.72, 95% CI, [0.61-0.85], p < 0.001, maternal smoking; aOR 2.84, 95% CI, [1.33-6.06], p = 0.007, and nulliparity; aOR 1.79, 95% CI, [1.06-3.02], p = 0.030 were associated with administration of intrapartum antibiotics in women giving birth vaginally.

Conclusion

Antibiotic administration during pregnancy and birth may be influenced by social and lifestyle-factors. Understanding such risk factors may guide preventive strategies in order to avoid unnecessary use of antibiotics.

A qualitative study of GP, NP and patient views about the use of rapid streptococcal antigen detection tests (RADTs) in primary care: 'swamped with sore throats?'

OBJECTIVE

To explore patient and healthcare professionals' (HCP) views of clinical scores and rapid streptococcal antigen detection tests (RADTs) for acute sore throat.

DESIGN

Qualitative semistructured interview study.

SETTING

UK primary care.

PARTICIPANTS

General practitioners (GPs), nurse practitioners (NPs) and patients from general practices across Hampshire, Oxfordshire and the West Midlands who were participating in the Primary Care Streptococcal Management (PRISM) study.

METHOD

Semistructured, face-to-face and phone interviews were conducted with GPs, NPs and patients from general practices across Hampshire, Oxfordshire and the West Midlands.

RESULTS

51 participants took part in the study. Of these, 42 were HCPs (29 GPs and 13 NPs) and 9 were patients. HCPs could see a positive role for RADTs in terms of reassurance, as an educational tool for patients, and for aiding inexperienced practitioners, but also had major concerns about RADT use in clinical practice. Particular concerns included the validity of the tests (the role of other bacteria, and carrier states), the tension and possible disconnect with clinical assessment and intuition, the issues of time and resource use and the potential for medicalisation of self-limiting illness. In contrast, however, experience of using RADTs over time seemed to make some participants more positive about using the tests. Moreover, patients were much more positive about the place of RADTs in providing reassurance and in limiting their antibiotic use.

CONCLUSIONS

It is unlikely that RADTs will have a (comfortable) place in clinical practice in the near future until health professionals' concerns are met, and they have direct experience of using them. The routine use of clinical scoring systems for acute upper respiratory illness also face important barriers related to clinicians' perceptions of their utility in the face of clinician experience and intuition.

Challenges in assessing nursing home residents with advanced dementia for suspected urinary tract infections

OBJECTIVES

To describe the presentation of suspected urinary tract infections (UTIs) in nursing home (NH) residents with advanced dementia and how they align with minimum criteria to justify antimicrobial initiation.

DESIGN

Twelve-month prospective study.

SETTING

Twenty-five NHs.

PARTICIPANTS

Two hundred sixty-six NH residents with advanced dementia.

MEASUREMENTS

Charts were abstracted monthly for documentation of suspected UTI episodes to determine whether episodes met minimum criteria to initiate antimicrobial therapy according to consensus guidelines.

RESULTS

Seventy-two residents experienced 131 suspected UTI episodes. Presenting symptoms and signs for these episodes are mental status change (44.3%), fever (20.6%), hematuria (6.9%), dysuria (3.8%), costovertebral tenderness (2.3%), urinary frequency (1.5%), rigor (1.5%), urgency (0%), and suprapubic pain (0%). Only 21 (16.0%) episodes met minimal criteria to initiate antimicrobial therapy based on signs and symptoms. Of the 110 episodes that lacked minimum criteria to justify antimicrobial initiation, 82 (74.5%) were treated with antimicrobial therapy. Urinalyses and urine culture results were available for 101 episodes, of which 80 (79.2%) had positive results on both tests. The proportion of episodes with a positive urinalysis and culture was similar for those that met (83.3%) and did not meet (78.3%) minimum criteria (P = .06).

CONCLUSION

The symptoms and signs necessary to meet minimum criteria to support antimicrobial initiation for UTIs are frequently absent in NH residents with advanced dementia. Antimicrobial therapy is prescribed for the majority of suspected UTIs that do not meet these minimum criteria. Urine specimens are frequently positive regardless of symptoms. These observations underscore the need to reconsider the diagnosis and the initiation of treatment for suspected UTIs in advanced dementia.

Home screening for bacteriuria in children with spina bifida and clean intermittent catheterization

Background

Significant bacteriuria (SBU) and urinary tract infections (UTIs) are common in patients with spina bifida and neuropathic detrusor sphincter dysfunction. Laboratory agar plated culture is the gold standard to establish SBU. It has the disadvantage of diagnostic and subsequent therapeutic delay. Leukocyte esterase tests (LETs) and dip slides proved to be useful in the general populations to exclude SBU and UTI. The aim of this study was to evaluate the reliability of LET and dip slide in children with spina bifida without symptoms of UTI. The reliability in children with asymptomatic SBU was not studied before.

Methods

In one hundred and twelve children with spina bifida on clean intermittent catheterization LETs and dip slides were compared with laboratory cultures. Both tests and agar plated cultures were performed on catheterized urine samples. The hypothesis was that the home tests are as accurate as laboratory cultures.

Results

A SBU was found in 45 (40%) of the 112 laboratory cultures. A negative LET excluded SBU (negative predictive value 96%), while a positive LET had a positive predictive value of 72%. The false positive rate was 28%. Dip slide determination of bacterial growth had no added value, other than serving as transport medium.

Conclusions

In spina bifida children, leukocyte esterase testing can be used to exclude significant bacteriuria at home, while dip slide tests have no added value to diagnose or exclude significant bacteriuria.

Measurement of nitrite in urine by gas chromatography-mass spectrometry

Nitric oxide (NO) is enzymatically produced from L-arginine and has a variety of biological functions. Autoxidation of NO in aqueous media yields nitrite (O = N-O(-)). NO and nitrite are oxidized in erythrocytes by oxyhemoglobin to nitrate (NO(3)(-)). Nitrate reductases from bacteria reduce nitrate to nitrite. Nitrite and nitrate are ubiquitous in nature, they are present throughout the body and they are excreted in the urine. Nitrite in urine has been used for several decades as an indicator and measure of bacteriuria. Since the identification of nitrite as a metabolite of NO, circulating nitrite is also used as an indicator of NO synthesis and is considered an NO storage form. In contrast to plasma nitrite, the significance of nitrite in the urine beyond bacteriuria is poorly investigated and understood. This chapter describes a gas chromatography-mass spectrometry (GC-MS) protocol for the quantitative determination of nitrite in urine of humans. Although the method is useful for detection and quantification of bacteriuria, the procedures described herein are optimum for urinary nitrite in conditions other than urinary tract infection. The method uses [(15)N]nitrite as internal standard and pentafluorobenzyl bromide as the derivatization agent. Derivatization is -performed on 100-μL aliquots and quantification of toluene extracts by selected-ion monitoring of m/z 46 for urinary nitrite and m/z 47 for the internal standard in the electron-capture negative-ion chemical ionization mode.

Predicting acute uncomplicated urinary tract infection in women: a systematic review of the diagnostic accuracy of symptoms and signs

Background

Acute urinary tract infections (UTI) are one of the most common bacterial infections among women presenting to primary care. However, there is a lack of consensus regarding the optimal reference standard threshold for diagnosing UTI. The objective of this systematic review is to determine the diagnostic accuracy of symptoms and signs in women presenting with suspected UTI, across three different reference standards (10² or 10³ or 10⁵ CFU/ml). We also examine the diagnostic value of individual symptoms and signs combined with dipstick test results in terms of clinical decision making.

Methods

Searches were performed through PubMed (1966 to April 2010), EMBASE (1973 to April 2010), Cochrane library (1973 to April 2010), Google scholar and reference checking.

Studies that assessed the diagnostic accuracy of symptoms and signs of an uncomplicated UTI using a urine culture from a clean-catch or catherised urine specimen as the reference standard, with a reference standard of at least ≥ 10² CFU/ml were included. Synthesised data from a high quality systematic review were used regarding dipstick results. Studies were combined using a bivariate random effects model.

Results

Sixteen studies incorporating 3,711 patients are included. The weighted prior probability of UTI varies across diagnostic threshold, 65.1% at ≥ 10² CFU/ml; 55.4% at ≥ 10³ CFU/ml and 44.8% at ≥ 10² CFU/ml ≥ 10⁵ CFU/ml. Six symptoms are identified as useful diagnostic symptoms when a threshold of ≥ 10² CFU/ml is the reference standard. Presence of dysuria (+LR 1.30 95% CI 1.20-1.41), frequency (+LR 1.10 95% CI 1.04-1.16), hematuria (+LR 1.72 95%CI 1.30-2.27), nocturia (+LR 1.30 95% CI 1.08-1.56) and urgency (+LR 1.22 95% CI 1.11-1.34) all increase the probability of UTI. The presence of vaginal discharge (+LR 0.65 95% CI 0.51-0.83) decreases the probability of UTI. Presence of hematuria has the highest diagnostic utility, raising the post-test probability of UTI to 75.8% at ≥ 10² CFU/ml and 67.4% at ≥ 10³ CFU/ml. Probability of UTI increases to 93.3% and 90.1% at ≥ 10² CFU/ml and ≥ 10³ CFU/ml respectively when presence of hematuria is combined with a positive dipstick result for nitrites. Subgroup analysis shows improved diagnostic accuracy using lower reference standards ≥ 10² CFU/ml and ≥ 10³ CFU/ml.

Conclusions

Individual symptoms and signs have a modest ability to raise the pretest-risk of UTI. Diagnostic accuracy improves considerably when combined with dipstick tests particularly tests for nitrites.

The diagnosis of urinary tract infection: a systematic review

BACKGROUND

Urinary tract infections (UTI) are among the leading reasons for treatment in adult primary care medicine, accounting for a considerable percentage of antibiotic prescriptions. Because this problem is so common and so significant in routine clinical practice, a high level of diagnostic accuracy is essential. Antibiotics should not be prescribed excessively, particularly in view of the increasing prevalence of antibiotic resistance.

METHOD

Systematic review of relevant articles that were retrieved by a search of the Medline, Embase, and Cochrane Library databases. The recommendations of selected international guidelines were also taken into account, as were the German national quality standards for microbiological diagnosis.

RESULTS

The diagnosis of UTI by clinical criteria alone has an error rate of approximately 33%. The use of refined diagnostic algorithms does not completely eliminate uncertainty.

CONCLUSION

With the aid of a small number of additional diagnostic criteria, antibiotic treatment for UTI can be provided more specifically and thus more effectively. Differentiating UTI from asymptomatic bacteriuria, which usually requires no treatment, can lower the frequency of unnecessary antibiotic prescriptions.

Symptomatic treatment (ibuprofen) or antibiotics (ciprofloxacin) for uncomplicated urinary tract infection?--results of a randomized controlled pilot trial

BACKGROUND

Uncomplicated lower urinary tract infections (UTI) are usually treated with antibiotics. However, there is little evidence for alternative therapeutic options.This pilot study was set out 1) to make a rough estimate of the equivalence of ibuprofen and ciprofloxacin for uncomplicated urinary tract infection with regard to symptom resolution, and 2) to demonstrate the feasibility of a double-blind, randomized controlled drug trial in German general practices.

METHODS

We performed a double-blind, randomized controlled pilot trial in 29 German general practices. Eighty otherwise healthy women aged 18 to 85 years, presenting with at least one of the main UTI symptoms dysuria and frequency and without any complicating factors, were randomly assigned to receive either ibuprofen 3 x 400 mg oral or ciprofloxacin 2 x 250 mg (+1 placebo) oral, both for three days.Intensity of main symptoms--dysuria, frequency, low abdominal pain--was recorded at inclusion and after 4, 7 and 28 days, scoring each symptom from 0 (none) to 4 (very strong). The primary endpoint was symptom resolution on Day 4. Secondary outcomes were the burden of symptoms on Days 4 and 7 (based on the sum score of all symptoms), symptom resolution on Day 7 and frequency of relapses. Equivalence margins for symptom burden on Day 4 were pre-specified as +/- 0.5 sum score points. Data analysis was done by intention to treat and per protocol. Randomization was carried out on patient level by computer programme in blocks of six.

RESULTS

Seventy-nine patients were analyzed (ibuprofen n = 40, ciprofloxacin n = 39). On Day 4, 21/36 (58.3%) of patients in the ibuprofen-group were symptom-free versus 17/33 (51.5%) in the ciprofloxacin-group. On Day 4, ibuprofen patients reported fewer symptoms in terms of total sum score (1; SD 1,42) than ciprofloxacin patients (1,3; SD 1,9), difference -0,33 (95% CI (-1,13 to +0,47)), PP (per protocol) analysis. During Days 0 and 9, 12/36 (33%) of patients in the ibuprofen-group received secondary antibiotic treatment due to ongoing or worsening symptoms, compared to 6/33 (18%) in the ciprofloxacin-group (non significant). A total of 58 non-serious adverse events were reported, 32 in the ibuprofen group versus 26 in the ciprofloxacin group (non significant).

CONCLUSIONS

Our results support the assumption of non-inferiority of ibuprofen compared to ciprofloxacin for treatment of symptomatic uncomplicated UTI, but need confirmation by further trials.

TRIAL REGISTRATION

TRIAL REGISTRATION NUMBER

ISRCTN00470468. See Commentary http://www.biomedcentral.com/1471-2296/11/42.