Validating the prediction of lower urinary tract infection in primary care: sensitivity and specificity of urinary dipsticks and clinical scores in women

'When all you have is a hammer, everything has to be a nail': Managing diagnostic uncertainty in urinary tract infection

Diagnosis of urinary tract infections (UTI) is a routine part of medical work and yet is well recognised to be an area of high clinical uncertainty. Meanwhile, diagnosis of UTI is becoming increasingly important to policymakers globally due to concerns about antibiotic over-prescription. Drawing on Mol's concept of ontological multiplicity in clinical work, I explore how diagnostic uncertainty is co-ordinated into certainty by a UK national diagnostic algorithm for UTI. The diagnosis of UTI is produced or withheld as a post hoc rationalisation of a prior decision whether to prescribe antibiotics or not. Work in the sociology of diagnosis has already noted that diagnostic steps are often re-ordered by health-care professionals taking diverse actions in the best interest of their patients. This article contributes an argument that ordering diagnostic work around antimicrobial stewardship agendas has the effect of narrowing possible actions. Exploring the consequences and effects of doing diagnosis in this way for different groups, I argue that a greater creativity about what could be done to care for painful bladders could be found in a return to more clinical ways of working.

Performance of an innovative culture-based digital dipstick for detection of bacteriuria

IMPORTANCE

In this study, we explore the transformative potential of UTI-lizer, an emerging technology not yet commercially available. Our manuscript shows that UTI-lizer is a promising alternative for detecting the five main pathogens that cause urinary tract infections (UTIs). The results also indicate that digital dipsticks have the potential to uniquely provide UTI diagnostic quality on par with that of gold-standard testing, with the added benefits of ease of testing, rapid test handling time, and simple test equipment. This technology can be helpful in quickly ruling out bacterial infections and reducing the unnecessary use of antibiotics, especially in primary care settings or at the point of care. Moreover, the UTI-lizer test can reduce the number of negative urine samples sent to central laboratories, thus easing the burden of UTI diagnostics on the healthcare system. We believe our study, as well as current and upcoming research based on this technology, is highly relevant for clinical microbiologists, microbiology scientists, general practitioners, and urologists.

Impact of sociodemographic status and UTI symptoms on women's health-care seeking and management in England: findings from an e-survey conducted during the first year of the COVID-19 pandemic

BACKGROUND

Multiple factors may influence women's experiences of urinary tract infection (UTI) and its clinical management.

AIM

To explore how women's background, symptoms, and severity of symptoms influence UTI reporting and management.

DESIGN & SETTING

Internet questionnaire targeting women in England, focusing on UTI symptoms, care seeking, and management.

METHOD

A total of 1096 women aged ≥16 years with UTI symptoms in the previous year completed the questionnaire in March and April 2021. Multivariable logistic regression was ued to estimate the odds of relevant outcomes while adjusting for background characteristics.

RESULTS

Women with children in their household, who were aged under 45 years, or who were married or cohabitating were more likely to experience UTI symptoms. The odds of antibiotic prescribing were lower if women reported dysuria (adjusted odds ratio [AOR] = 0.65, 95% confidence interval [CI] = 0.49 to 0.85), frequency (AOR = 0.63, 95% CI = 0.48 to 0.83), or vaginal discharge (AOR = 0.69, 95% CI = 0.50 to 0.96), but higher if reporting haematuria (AOR = 2.81, 95% CI = 1.79 to 4.41), confusion (AOR = 2.14, 95% CI = 1.16 to 3.94), abdominal pain (AOR = 1.35, 95% CI = 1.04 to 1.74), or systemic symptoms (AOR = 2.04, 95% CI = 1.56 to 2.69). Those with abdominal pain or two or more of nocturia, dysuria, or cloudy urine had lower odds of receiving a delayed antibiotic, while those with incontinence, confusion, unsteadiness, or low temperature had higher odds of a delayed prescription. Increasing symptom severity was associated with greater odds of receiving antibiotics.

CONCLUSION

Except for reduced prescribing if a woman had dysuria and frequency, antibiotic prescribing followed an expected pattern, aligning generally with national guidance. Symptom severity and the likelihood of systemic infection probably influenced care seeking and prescribing. Sexual intercourse and childbirth may be key times to target women with messages about UTI prevention.

Impact of Menopausal Status and Recurrent UTIs on Symptoms, Severity, and Daily Life: Findings from an Online Survey of Women Reporting a Recent UTI

Introduction: Current UKHSA UTI diagnostic guidance advises empirical antibiotics if two of the following symptoms are present: cloudy urine, dysuria, and new onset nocturia. Hormonal changes during menopause may impact UTI symptoms, and qualitative studies suggest women with recurrent UTIs may present with different UTI symptoms. This study aims to assess whether menopausal status and the presence of recurrent UTIs impact UTI symptoms in women. Methods: An e-survey was conducted between 13 March 2021 and 13 April 2021. Women aged 16 years or older with a history of a UTI in the last year were eligible for inclusion. We defined menopause as those aged 45-64 years; pre-menopause as those less than 45 years; and post-menopause as those 65 years and older. Recurrent UTIs were defined as three or more UTIs in the last year. The data were weighted to be representative of the UK population. Crude unadjusted and adjusted odds ratios were estimated using logistic regression. Results: In total, 1096 women reported a UTI in the last year. There were significant differences in UTI symptoms based on menopausal status and the presence of recurrent UTIs. Post-menopausal women self-reported more incontinence (OR 2.76, 95% CI 1.50,5.09), whereas menopausal women reported more nocturia. Women with recurrent UTIs reported less dysuria, more severe symptoms (OR 1.93 95% CI 1.37,2.73) and a greater impact on daily life (OR 1.68, 95% CI 1.19,2.37). Conclusions: This survey provides evidence that acute UTIs present differently based on menopausal status and in women with recurrent UTIs. It is important that healthcare professionals are aware of these differences when assessing women presenting with an acute UTI and, therefore, further research in this area is needed.

Evidence-based appraisal of two guidelines for the diagnosis of suspected, uncomplicated urinary tract infections in primary care: a diagnostic accuracy validation study

OBJECTIVES

Given the lack of accurate rapid diagnostics for urinary tract infection (UTI) in women, many countries have developed guidelines aiming to support appropriate antibiotic prescribing, but some guidelines have not been validated. We performed a diagnostic accuracy validation study of two guidelines: Public Health England (GW-1263) and Scottish Intercollegiate Guidelines Network (SIGN160).

METHODS

We used data from women with symptoms suggestive of uncomplicated UTI from a randomized controlled trial comparing urine collection devices. Symptom information was recorded via baseline questionnaire and primary care assessment. Women provided urine samples for dipstick testing and culture. We calculated the number within each risk category of diagnostic flowcharts who had positive/mixed growth/no significant growth urine culture. Results were presented as positive/negative predictive values, with 95% CIs.

RESULTS

Of women aged under 65 years, 311/509 (61.1%, 95% CI 56.7%-65.3%) classified to the highest risk category (recommended to consider immediate antibiotic prescribing) and 80/199 (40.2%, 95% CI 33.4%-47.4%) classified to the lowest risk category (recommended to reassure that UTI is less likely) by the GW-1263 guideline (n = 810) had positive culture. For the SIGN160 guideline (n = 814), the proportion with positive culture ranged from 60/82 (73.2%, 95% CI 62.1%-82.1%) in those for whom immediate treatment was indicated to 33/76 (43.4%, 95% CI 32.3%-55.3%) in those recommended a self-care/waiting strategy.

CONCLUSIONS

Clinicians should be aware of the potential for diagnostic error when using diagnostic guidelines for managing uncomplicated UTI and making antimicrobial prescribing decisions. Infection cannot be excluded on the basis of symptoms and dipstick testing alone.

Women’s information needs around urine testing for urinary tract infections: a qualitative study

Background

Urinary tract infection (UTI) is one of the commonest bacterial infections in general practice, with urine testing a frequent feature of its management. Urinary dipsticks are widely used, with urine culture the reference standard test. To avoid contamination, patients are advised to discard the first part of the urine stream, retaining the midstream part for the sample. This process, however, can be challenging both to explain and to perform. There is a lack of literature investigating women’s perceptions and understanding of urine sampling.

Aim

To explore women’s understanding of urine collection, sample contamination, and how information from samples informed UTI management.

Design and setting

Qualitative study embedded in a UK randomised controlled trial (RCT) of urinary collection devices (UCDs) among women attending primary care with a suspected UTI.

Method

Semi-structured telephone interviews were conducted with 29 women participating in the RCT. Interviews were transcribed and thematically analysed.

Results

Participants were not always aware about what midstream samples were and why they were preferable. They also lacked understanding about how urine samples may be contaminated, and sources of contamination. Participants experienced variability in the information received following analysis of their sample.

Conclusion

Provision of clear information could help provide better urine samples, aiding the diagnosis of UTIs, presenting results with greater clarity, and creating less need for repeat samples. Sharing of information derived from uncontaminated samples may also support better UTI management, helping to reduce unnecessary prescribing and antibiotic resistance.

Uncomplicated urinary tract infection in primary health care: presentation and clinical outcome

BACKGROUND

Uncomplicated urinary tract infection (UTI) causes bothersome symptoms among women and is a leading cause for antibiotic prescribing in primary healthcare (PHC).

METHODS

A prospective observational study in eight different PHC centres in Sweden including 192 women with symptoms of uncomplicated UTI. Questionnaires and symptom diaries were used to retrieve patient data. All urine samples were analysed with urine culture and susceptibility testing. The aim was to describe the clinical presentation of symptoms in uncomplicated UTI in relation to bacterial findings in urine and to describe the course and duration of symptoms in relation to anamnestic factors, bacterial findings and antibiotic treatment.

RESULTS

Median symptom duration before seeking care was four days (IQR 1-7). Restrictions in daily life related to symptoms of uncomplicated UTI were reported by the majority (74%) of respondents. The median number of days concerning any symptom after consultation was 4.0 days (IQR 2.0-5.0) for patients treated with antibiotics, and 6.5 days (IQR 3.0-10.0) for patients not treated with antibiotics. There was an association between longer symptom duration after consultation and age over 50 years, relative risk (RR) 1.76 (95% CI 1.25-2.49). Antibiotic treatment RR 0.47 (95% CI 0.27-0.81) was associated with reported shorter duration of symptoms.

CONCLUSIONS

Women visiting primary health care with symptoms indicating uncomplicated UTI have symptoms for several days before seeking care and after consulting. A majority of patients feel restricted in their daily activities due to uncomplicated UTI. Older women and women not treated with antibiotics have the longest symptom duration after consultation.

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.

Predicting the use of antibiotics after initial symptomatic treatment of an uncomplicated urinary tract infection: analyses performed after a randomised controlled trial

OBJECTIVE

To predict antibiotic use after initial treatment with ibuprofen using data from a randomised controlled trial comparing ibuprofen to pivmecillinam in the treatment of women with symptoms of an uncomplicated urinary tract infection (UTI).

SETTING

16 sites in a primary care setting in Norway, Sweden and Denmark.

PARTICIPANTS

Data from 181 non-pregnant women aged 18-60 presenting with symptoms of uncomplicated UTI, initially treated with ibuprofen.

METHODS

Using the least absolute shrinkage and selection operator logistic regression model, we conducted analyses to see if baseline information could help us predict which women could be treated with ibuprofen without risking treatment failure and which women should be recommended antibiotics.

RESULTS

Of the 143 women included in the final analysis, 77 (53.8%) recovered without antibiotics and 66 (46.2 %) were subsequently prescribed antibiotics. In the unadjusted binary logistic regression, the number of days with symptoms before inclusion (<3 days) and feeling moderately unwell or worse (≥4 on a scale of 0-6) were significant predictors for subsequent antibiotic use. In the adjusted model, no predictors were significantly associated with subsequent antibiotic use. The area under the curve of the final model was 0.66 (95% CI: 0.57 to 0.74).

CONCLUSION

We did not find any baseline information that significantly predicted the use of antibiotic treatment. Identifying women who need antibiotic treatment to manage their uncomplicated UTI is still challenging. Larger data sets are needed to develop models that are more accurate.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT01849926).

Antibiotic prescribing for the older adult: beliefs and practices in primary care

BACKGROUND

Older adults suffer high morbidity and mortality following serious infections, and hospital admissions with these conditions are increasingly common. Antibiotic prescribing in the older adult population, especially in long-term care facilities, has been argued to be inappropriately high. In order to develop the evidence base and provide support to GPs in achieving antimicrobial stewardship in older adults it is important to understand their attitudes and beliefs toward antibiotic prescribing in this population.

OBJECTIVES

To understand the attitudes and beliefs held by GPs regarding antibiotic prescribing in older adults.

METHODS

Semi-structured qualitative interviews were conducted with 28 GPs working in the UK. Data analysis followed a modified framework approach.

RESULTS

GPs described antibiotic prescribing in older adults as differing from prescribing in other age groups in a number of ways, including prescribing broad-spectrum, longer and earlier antibiotics in this population. There were also rationales for situations where antibiotics were prescribed despite there being no clear diagnosis of infection. Trials of antibiotics were used both as diagnostic aids and in an attempt to avoid admission. The risks of antibiotics were understood, but in some cases restrictions on antibiotic use were thought to hamper optimal management of infection in this age group.

CONCLUSIONS

Diagnosing serious infections in older adults is challenging and antibiotic prescribing practices reflect this challenge, but also reflect an absence of clear guidance or evidence. Research that can fill the gaps in the evidence base is required in order to support GPs with their critical antimicrobial stewardship role in this population.

Evaluation of a community pharmacy-led test-and-treat service for women with uncomplicated lower urinary tract infection in England

Background

Uncomplicated lower urinary tract infections (UTIs) are common in women consulting primary healthcare, taking up GP resources. Delayed consultation can increase the risk of serious infections such as pyelonephritis or bacteraemia.

Objectives

To evaluate the effectiveness and uptake of a lower UTI test-and-treat service for women presenting with urinary symptoms within a community pharmacy in supporting self-care and appropriate use of antibiotics and reducing demand on other NHS resources.

Methods

The service was aligned to national guidelines to diagnose and treat lower UTI in women aged 16–64 years and used national resources to provide safety-netting and self-care advice. Consultation included clinical assessment and a urine dipstick test alongside a novel smartphone app, with diagnosis informed by test results. Women were provided with safety-netting advice and either advised on self-care, supplied with antibiotics or referred to their GP.

Results

Data were analysed for 764 women who presented to 23 pharmacies during December 2018 to April 2019. Lower UTI was found to be likely in 372/496 (75.0%) women, most of whom purchased antibiotics on the same day. Had the service not been available, approximately three-quarters of women who had completed the service and responded to the question would have visited their GP (214/301) and more than one-third would have used self-care with or without going to see their GP (116/301).

Conclusions

A community pharmacy-led UTI test-and-treat service for women aged 16–64 years presenting with urinary symptoms provided accessible and timely care aligned to national guidance, with 75.0% of consultations requiring antibiotic treatment.

Automated urinalysis combining physicochemical analysis, on-board centrifugation, and digital imaging in one system: A multicenter performance evaluation of the cobas 6500 urine work area

BACKGROUND

We evaluated the analytical performance of the fully automated cobas® 6500 urine work area and its automated components-cobas u 601 and cobas u 701.

DESIGN AND METHODS

The study was conducted at three European centers using un-centrifuged surplus routine urine samples; all measurements were performed within 2 h of sample collection. Precision, sample carry-over, and method comparisons were evaluated per Clinical and Laboratory Standards Institute guidelines. Method comparisons: cobas u 601 versus Urisys 2400 and cobas u 411 urine test strips; and cobas u 701 versus KOVA® visual microscopy and iQ200 analyzer. Operability and functionality were assessed using questionnaires.

RESULTS

Precision of the entire cobas 6500 system was within predefined acceptance limits and no significant carry-over was observed. Erythrocytes, leukocytes, nitrites, and protein were in good agreement (≥93%) with cobas u 411 reflectometry. High correlation was shown between the cobas u 701 analyzer and KOVA visual microscopy for red blood cells (RBC; slope, 0.89; Pearson's r, 0.95) and white blood cells (WBC; slope, 0.96; Pearson's r, 0.96), demonstrating equivalence of test results. The 97.5% percentile reference values on the cobas u 701 analyzer were 5.3 cells/μL (RBC) and 6.2 cells/μL (WBC). The cobas 6500 system showed good sensitivity for small bacteria (>1 μm) and pathological casts, and the user interface, maintenance wizards, and system design were highly rated by operators.

CONCLUSIONS

The fully automated workflow, high precision, and high throughput of the cobas 6500 system have the potential to facilitate standardization of urine screening.

A cost-minimization analysis of treatment options for postmenopausal women with dysuria

BACKGROUND

Empiric therapy for urinary tract infection is difficult in postmenopausal women because of the higher rates of confounding lower urinary tract symptoms and differential resistance profiles of uropathogens in this population.

OBJECTIVE

The objective of the study was to determine the least costly strategy for treatment of postmenopausal women with the primary complaint of dysuria.

STUDY DESIGN

We performed a cost minimization analysis modeling the following clinical options: (1) empiric antibiotic therapy followed by urine culture, (2) urinalysis with empiric antibiotic therapy only if positive nitrites and leukocyte esterase, or (3) waiting for culture prior to initiating antibiotics. For all strategies we included nitrofurantoin, trimethoprim/sulfamethoxazole, fosfomycin, ciprofloxacin, or cephalexin. Pathogens included Escherichia coli, Enterococcus faecalis, Klebsiella pneumonaie, or Proteus mirabalis. Pathogens, resistance, treatment success, and medication side effects were specific to postmenopausal women.

RESULTS

Cost minimization modeling with TreeAge Pro assumed 73.4% of urinary tract infections were caused by Escherichia coli with 24.4% resistance to nitrofurantoin, trimethoprim/sulfamethoxazole. With our assumptions, empiric antibiotics with nitrofurantoin, trimethoprim/sulfamethoxazole was the least costly approach ($89.64/patient), followed by waiting for urine culture ($97.04/patient). Except for empiric antibiotics with fosfomcyin, empiric antibiotics was always less costly than using urinalysis to discriminate antibiotic use. This is due to the cost of urinalysis ($38.23), high rate of both urinary tract infection (91%), and positive urinalysis (69.3%) with dysuria in postmenopausal women and resultant high rate of antibiotic use with or without urinalysis. Options with fosfomycin were the most expensive because of the highest drug costs ($98/dose), and tornado analyses showed fosfomycin cost was the most impactful variable for model outcomes. Sensitivity analyses showed empiric fosfomycin became the least costly option if drug costs were $25.80, a price still more costly than almost all modeled baseline drug costs. This outcome was largely predicated on low resistance to fosfomycin. Conversely, ciprofloxacin was never the least costly option because of higher resistance and side effect cost, even if the drug cost was $0. We modeled 91% positive urine culture rate in postmenopausal women with dysuria; waiting for the urine culture prior to treatment would be the least costly strategy in a population with a predicted positive culture rate of <65%.

CONCLUSION

The least costly strategy was empiric antibiotics with nitrofurantoin and trimethoprim/sulfamethoxazole, followed by waiting on culture results. Local resistance patterns will have an impact on cost minimization strategies. Empiric fosfomycin would be least costly with reduced drug costs, even at a level at which drug costs were higher than almost all other antibiotics. In a population with high posttest probability of positive urine culture, urinalysis adds unnecessary cost. Antibiotic stewardship programs should continue efforts to decrease fluoroquinolone use because of high resistance, side effects, and increased cost.

Treatment of infections caused by multidrug-resistant Gram-negative bacteria: report of the British Society for Antimicrobial Chemotherapy/Healthcare Infection Society/British Infection Association Joint Working Party

The Working Party makes more than 100 tabulated recommendations in antimicrobial prescribing for the treatment of infections caused by multidrug-resistant (MDR) Gram-negative bacteria (GNB) and suggest further research, and algorithms for hospital and community antimicrobial usage in urinary infection. The international definition of MDR is complex, unsatisfactory and hinders the setting and monitoring of improvement programmes. We give a new definition of multiresistance. The background information on the mechanisms, global spread and UK prevalence of antibiotic prescribing and resistance has been systematically reviewed. The treatment options available in hospitals using intravenous antibiotics and in primary care using oral agents have been reviewed, ending with a consideration of antibiotic stewardship and recommendations. The guidance has been derived from current peer-reviewed publications and expert opinion with open consultation. Methods for systematic review were NICE compliant and in accordance with the SIGN 50 Handbook; critical appraisal was applied using AGREE II. Published guidelines were used as part of the evidence base and to support expert consensus. The guidance includes recommendations for stakeholders (including prescribers) and antibiotic-specific recommendations. The clinical efficacy of different agents is critically reviewed. We found there are very few good-quality comparative randomized clinical trials to support treatment regimens, particularly for licensed older agents. Susceptibility testing of MDR GNB causing infection to guide treatment needs critical enhancements. Meropenem- or imipenem-resistant Enterobacteriaceae should have their carbapenem MICs tested urgently, and any carbapenemase class should be identified: mandatory reporting of these isolates from all anatomical sites and specimens would improve risk assessments. Broth microdilution methods should be adopted for colistin susceptibility testing. Antimicrobial stewardship programmes should be instituted in all care settings, based on resistance rates and audit of compliance with guidelines, but should be augmented by improved surveillance of outcome in Gram-negative bacteraemia, and feedback to prescribers. Local and national surveillance of antibiotic use, resistance and outcomes should be supported and antibiotic prescribing guidelines should be informed by these data. The diagnosis and treatment of both presumptive and confirmed cases of infection by GNB should be improved. This guidance, with infection control to arrest increases in MDR, should be used to improve the outcome of infections with such strains. Anticipated users include medical, scientific, nursing, antimicrobial pharmacy and paramedical staff where they can be adapted for local use.

Pre-test probability of urinary tract infection in dogs with clinical signs of lower urinary tract disease

Clinical signs of lower urinary tract disease in dogs are characteristic but non-specific for infection. It has been hypothesized that age, sex and neuter status influences the prevalence of urinary tract infection (UTI), but the predictive value of the combined clinical presentation has not been explored in dogs. The aim of the study was to assess clinical predictors (sex/neuter status, age, dysuria/stranguria, pollakiuria, macroscopic hematuria, malodorous urine and history of recurrent UTI) for bacterial cystitis, and to develop a clinical decision rule. Data was retrieved from medical records (retrospective cases) or from standardized recording sheets (prospective cases). Bacterial cystitis was defined as significant bacteriuria on quantitative bacterial culture in dogs with compatible clinical signs of urinary tract disease. Dogs of any breed, sex and age were included. A total of 1727 microbiology records were screened and 424 samples were included in the analysis. Bacterial cystitis was confirmed in 46% of the cases. Four variables predicted bacterial cystitis: sex/neuter status, age, pollakiuria and hematuria. A score was designated to each variable and a clinical rule was constructed. This rule attained an AUC of 0.75 and had sensitivity of 83% and specificity of 55% at its optimal cut-off (score ≥2.0). A score cut-off of ≥3.0 had a positive predictive value of 70%. Several factors predicted bacterial cystitis, but the clinical rule had only modest predictive value. Other variables or point-of-care test results should be included in future research to optimize overall precision.

Uncomplicated urinary tract infections in Swedish primary care; etiology, resistance and treatment

Background

Uncomplicated urinary tract infection (uUTI) is common and a majority of patients are prescribed antibiotics. There is little knowledge about antibiotic resistance in urine samples from patients with uUTI in primary health care (PHC).

The aim was to describe antibiotic treatment, bacterial findings, the prevalence of resistant E.coli and factors associated with antibiotic resistance. The aim was also to compare the prevalence of resistant E.coli in clinical practice with the prevalence of resistant E.coli in routine microbiological laboratory data.

Methods

This observational study in PHC setting started in November 2014 and ended in March 2016. Women aged 17 years and older with symptoms indicating uUTI from eight PHCs were included. Questionnaires were used to retrieve anamnestic data. All urine samples were sent to the local laboratory of microbiology for diagnostic analysis and susceptibility testing. Proportions of resistant E.coli were compared with corresponding data from the regional laboratory.

Results

Urine cultures were analysed in 304 women with a median age of 46 (IQR 32–66) years. Bacterial growth was found in 243 (80%) of urine samples, and E.coli in 72% of the positive samples. A total of 80% of detected E.coli isolates were susceptible to all tested antimicrobials and resistance rates to ciprofloxacin were lower than reported from the local clinical laboratory. Antibiotic treatment within the last year was independently associated with antibiotic resistant E.coli in the urine sample adjusted OR 4.97 (95% CI 2.04–12.06). A total of 74% of the women were treated with antibiotics. The most prescribed was pivmecillinam followed by nitrofurantoin.

Conclusions

Antibiotic resistance in E.coli was low. Antibiotic treatment within the last year was associated with antibiotic resistant E.coli. Data from the clinical microbiology laboratory indicates that laboratory data may overestimate antibiotic resistance and lead to an unnecessary change in empiric antibiotic treatment of uUTI in primary care. The empirically prescribed antibiotics, were inline with Swedish treatment recommendations for uUTI.

Predictors of Symptom Duration and Bacteriuria in Uncomplicated Urinary Tract Infection

OBJECTIVE

To identify baseline predictors of symptom duration after empirical treatment for uncomplicated urinary tract infection (UTI) and significant bacteriuria in a cohort of women treated for UTI.

DESIGN

Prospective single-centre cohort study.

SETTING

Outpatient clinic in Norway.

PATIENTS

From September 2010 to November 2011, 441 women aged 16-55 years with symptoms of uncomplicated UTI were included.

RESULTS

Dipstick findings of leukocyte esterase 1 + (incidence rate ratio (IRR) 1.93, 95% confidence interval (CI) 1.23-3.01, p < 0.01) and microbe resistant to mecillinam treatment (IRR 1.41, 95% CI 1.07-1.89, p = 0.02) predicted longer symptom duration. More pronounced symptoms did not predict longer symptom duration (IRR 1.18, 95% CI 0.94-1.46, p = 0.15) or significant bacteriuria (odds ratio [OR] 1.16, 95% CI 0.72-1.88, p = 0.54). Leukocyte esterase 2 + (OR 2.51, 95% CI 0.92-6.83, p = 0.07) or 3 + (OR 2.40, 95% CI 0.88-6.05, p = 0.09) and nitrite positive urine dipstick test (OR 3.22, 95% CI 1.58-7.01, p = <0.01) were associated with bacteriuria.

CONCLUSION

More pronounced symptoms did not correlate with significant bacteriuria or symptom duration after empirical treatment for acute cystitis. One might reconsider the current practice of treating uncomplicated UTI based on symptoms alone. Key Points Treatment strategies for milder infectious diseases must consider ways of reducing antibiotic consumption to decelerate the increase in antibiotic resistance. Our findings suggest that more emphasis should be put on urine dipstick results and bacteriological findings in the clinical setting. One might reconsider the current practice of treating uncomplicated UTIs based on symptoms alone.

Diagnosis and treatment of urinary tract infections across age groups

Urinary tract infections are the most common outpatient infections, but predicting the probability of urinary tract infections through symptoms and test results can be complex. The most diagnostic symptoms of urinary tract infections include change in frequency, dysuria, urgency, and presence or absence of vaginal discharge, but urinary tract infections may present differently in older women. Dipstick urinalysis is popular for its availability and usefulness, but results must be interpreted in context of the patient's pretest probability based on symptoms and characteristics. In patients with a high probability of urinary tract infection based on symptoms, negative dipstick urinalysis does not rule out urinary tract infection. Nitrites are likely more sensitive and specific than other dipstick components for urinary tract infection, particularly in the elderly. Positive dipstick testing is likely specific for asymptomatic bacteriuria in pregnancy, but urine culture is still the test of choice. Microscopic urinalysis is likely comparable to dipstick urinalysis as a screening test. Bacteriuria is more specific and sensitive than pyuria for detecting urinary tract infection, even in older women and during pregnancy. Pyuria is commonly found in the absence of infection, particularly in older adults with lower urinary tract symptoms such as incontinence. Positive testing may increase the probability of urinary tract infection, but initiation of treatment should take into account risk of urinary tract infection based on symptoms as well. In cases in which the probability of urinary tract infection is moderate or unclear, urine culture should be performed. Urine culture is the gold standard for detection of urinary tract infection. However, asymptomatic bacteriuria is common, particularly in older women, and should not be treated with antibiotics. Conversely, in symptomatic women, even growth as low as 10² colony-forming unit/mL could reflect infection. Resistance is increasing to fluoroquinolones, beta-lactams, and trimethoprim-sulfamethoxazole. Most uropathogens still display good sensitivity to nitrofurantoin. First-line treatments for urinary tract infection include nitrofurantoin, fosfomycin, and trimethoprim-sulfamethoxazole (when resistance levels are <20%). These antibiotics have minimal collateral damage and resistance. In pregnancy, beta-lactams, nitrofurantoin, fosfomycin, and trimethoprim-sulfamethoxazole can be appropriate treatments. Interpreting the probability of urinary tract infection based on symptoms and testing allows for greater accuracy in diagnosis of urinary tract infection, decreasing overtreatment and encouraging antimicrobial stewardship.

Point-of-care urine culture for managing urinary tract infection in primary care: a randomised controlled trial of clinical and cost-effectiveness

BACKGROUND

The effectiveness of using point-of-care (POC) urine culture in primary care on appropriate antibiotic use is unknown.

AIM

To assess whether use of the Flexicult^™ SSI-Urinary Kit, which quantifies bacterial growth and determines antibiotic susceptibility at the point of care, achieves antibiotic use that is more often concordant with laboratory culture results, when compared with standard care.

DESIGN AND SETTING

Individually randomised trial of females with uncomplicated urinary tract infection (UTI) in primary care research networks (PCRNs) in England, the Netherlands, Spain, and Wales.

METHOD

Multilevel regression compared outcomes between the two groups while controlling for clustering.

RESULTS

In total, 329 participants were randomised to POC testing (POCT) and 325 to standard care, and 324 and 319 analysed. Fewer females randomised to the POCT arm than those who received standard care were prescribed antibiotics at the initial consultation (267/324 [82.4%] versus 282/319 [88.4%], odds ratio [OR] 0.56, 95% confidence interval [CI] = 0.35 to 0.88). Clinicians indicated the POCT result changed their management for 190/301 (63.1%). Despite this, there was no statistically significant difference between study arms in antibiotic use that was concordant with laboratory culture results (primary outcome) at day 3 (39.3% POCT versus 44.1% standard care, OR 0.84, 95% CI = 0.58 to 1.20), and there was no evidence of any differences in recovery, patient enablement, UTI recurrences, re-consultation, antibiotic resistance, and hospitalisations at follow-up. POCT culture was not cost-effective.

CONCLUSION

Point-of-care urine culture was not effective when used mainly to adjust immediate antibiotic prescriptions. Further research should evaluate use of the test to guide initiation of 'delayed antibiotics'.

Variations in presentation, management, and patient outcomes of urinary tract infection: a prospective four-country primary care observational cohort study

BACKGROUND

Regional variations in the presentation of uncomplicated urinary tract infection (UTI) and pathogen sensitivity to antibiotics have been cited as reasons to justify differences in how the infections are managed, which includes the prescription of broad-spectrum antibiotics.

AIM

To describe presentation and management of UTI in primary care settings, and explore the association with patient recovery, taking microbiological findings and case mix into account.

DESIGN AND SETTING

Prospective observational study of females with symptoms of uncomplicated UTI presenting to primary care networks in England, Wales, the Netherlands, and Spain.

METHOD

Clinicians recorded history, symptom severity, management, and requested mid-stream urine culture. Participants recorded, in a diary, symptom severity each day for 14 days. Time to recovery was compared between patient characteristics and between countries using two-level Cox proportional hazards models, with patients nested within practices.

RESULTS

In total, 797 females attending primary care networks in England (n = 246, 30.9% of cohort), Wales (n = 213, 26.7%), the Netherlands (n = 133, 16.7%), and Spain (n = 205, 25.7%) were included. In total, 259 (35.8%, 95% confidence interval 32.3 to 39.2) of 726 females for whom there was a result were urine culture positive for UTI. Pathogens and antibiotic sensitivities were similar. Empirical antibiotics were prescribed for 95.1% in England, 92.9% in Wales, 95.1% in Spain, and 59.4% in the Netherlands There were no meaningful differences at a country network level before and after controlling for severity, prior UTIs, and antibiotic prescribing.

CONCLUSION

Variation in presentation and management of uncomplicated UTI at a country primary care network level is clinically unwarranted and highlights a lack of consensus concerning optimal symptom control and antibiotic prescribing.

External validation study of a clinical decision aid to reduce unnecessary antibiotic prescriptions in women with acute cystitis

Background

Empirical prescribing of antibiotics to women with symptoms of acute cystitis prior to culture results is common, but subsequent culture results are often negative. A clinical decision aid for prescribing decisions in acute cystitis was previously developed that could reduce these unnecessary antibiotic prescriptions but has not been validated. This study sought to validate this decision aid for empirical antibiotic prescribing decisions in a new cohort of women with suspected acute cystitis.

Methods

External validation study of a clinical decision aid in 397 women with symptoms of acute cystitis, involving 230 Canadian family practitioners across Canada between 2009 and 2011. The sensitivity and specificity of the decision aid compared to a gold standard positive urine culture (defined as ≥10² cfu/ml (≥10⁵ CFU/L)) was determined, and compared with physician management, and the earlier development cohort study estimates. Other outcomes assessed were total antibiotic prescriptions, unnecessary antibiotics for negative urine cultures, and recommendations for urine culture testing. Chi-square tests were used for unpaired comparisons, adjusted for physician clustering. McNemar’s test was used for paired comparisons.

Results

There were 245/397 (61.7%) positive urine cultures. The cystitis aid sensitivity was 202/245 (82.5%, 95% Confidence Interval (CI)) = 77.1%, 86.8%), compared to 167/208 (80.3%) in the previous development cohort (p = 0.54), and 239/245 (97.6%) by family physicians in the current study (p < 0.001). Specificity was low for physicians (10/152, 6.6%) compared to the decision aid (54/152, 35.5%; p < 0.001, resulting in more antibiotic prescriptions by physicians (381/397, 96.0%) than would occur with decision aid recommendations (300/397, 75.6%, p < 0.001). Unnecessary antibiotic prescriptions where urine cultures were negative would be reduced an absolute 11.1% with cystitis aid recommendations (98/397, 24.7%) compared to usual physician care (142/397, 35.8%; p = 0.001). Urine cultures would also be reduced (97/397, 24.4% decision aid vs 351/397, 88.4% physicians; p < 0.001).

Conclusions

A 3-item clinical decision aid demonstrated reproducible accuracy in two cohorts of women with acute cystitis symptoms. Clinically important reductions in total and unnecessary antibiotic use, as well as urine culture testing, could result with routine clinical use compared to current empirical physician management practices.

Electronic supplementary material

The online version of this article (10.1186/s12875-017-0660-y) contains supplementary material, which is available to authorized users.

Diagnosis, Treatment, and Prevention of Urinary Tract Infection

UTI may involve the lower or upper urinary tract and may be uncomplicated or complicated. The emphasis of this chapter is uncomplicated UTI. The diagnosis of uncomplicated cystitis (bladder infection) and pyelonephritis (kidney infection) is usually easily made based on the clinical presentation, whereas the diagnosis in patients with complicated UTI is often more complex. Thus uncomplicated cystitis is usually manifested by dysuria, frequency and/or urgency without fever, and pyelonephritis is usually manifested by fever and back pain/costovertebral angle tenderness. However, pyuria is usually present with UTI, regardless of location, and its absence suggests that another condition may be causing the patient's symptoms. Treatment of cystitis is usually straightforward with one of several effective short-course antimicrobial regimens, although antimicrobial resistance continues to increase and can complicate treatment choices in certain areas. Likewise, antimicrobial resistance has complicated our management of uncomplicated pyelonephritis since resistance of uropathogens to the fluoroquinolone class, the mainstay of oral treatment for pyelonephritis, is increasing worldwide, and some of the other agents used for cystitis are not recommended for pyelonephritis due to low tissue levels. The goal of prevention of recurrent cystitis is to minimize the use of antimicrobials and there are several research efforts in progress to develop effective and safe antimicrobial-sparing preventive approaches for this common condition.

Proposed Clinical Decision Rules to Diagnose Acute Rhinosinusitis Among Adults in Primary Care

PURPOSE

To reduce inappropriate antibiotic prescribing, we sought to develop a clinical decision rule for the diagnosis of acute rhinosinusitis and acute bacterial rhinosinusitis.

METHODS

Multivariate analysis and classification and regression tree (CART) analysis were used to develop clinical decision rules for the diagnosis of acute rhinosinusitis, defined using 3 different reference standards (purulent antral puncture fluid or abnormal finding on a computed tomographic (CT) scan; for acute bacterial rhinosinusitis, we used a positive bacterial culture of antral fluid). Signs, symptoms, C-reactive protein (CRP), and reference standard tests were prospectively recorded in 175 Danish patients aged 18 to 65 years seeking care for suspected acute rhinosinusitis. For each reference standard, we developed 2 clinical decision rules: a point score based on a logistic regression model and an algorithm based on a CART model. We identified low-, moderate-, and high-risk groups for acute rhinosinusitis or acute bacterial rhinosinusitis for each clinical decision rule.

RESULTS

The point scores each had between 5 and 6 predictors, and an area under the receiver operating characteristic curve (AUROCC) between 0.721 and 0.767. For positive bacterial culture as the reference standard, low-, moderate-, and high-risk groups had a 16%, 49%, and 73% likelihood of acute bacterial rhinosinusitis, respectively. CART models had an AUROCC ranging from 0.783 to 0.827. For positive bacterial culture as the reference standard, low-, moderate-, and high-risk groups had a likelihood of acute bacterial rhinosinusitis of 6%, 31%, and 59% respectively.

CONCLUSIONS

We have developed a series of clinical decision rules integrating signs, symptoms, and CRP to diagnose acute rhinosinusitis and acute bacterial rhinosinusitis with good accuracy. They now require prospective validation and an assessment of their effect on clinical and process outcomes.

Inadequate adherence to Swedish guidelines for uncomplicated lower urinary tract infections among adults in general practice

In a primary care study of urinary tract infections (UTIs) performed 2008 in Uppsala County, Sweden, 43% of the patients were culture negative. In order to investigate the background to the observed overdiagnosis of UTI, study invitations were sent to the previously included patients. A total of 256 patients (88% women) approved to participate. Patient charts and recorded laboratory data were reviewed. Two or more of the cardinal symptoms were reported in 53% of the women and in 19% of the men. A dipstick test was performed in 93% of the consultations. The highest positive predicted values in women had a positive nitrite test (95%, 95% CI 87; 99) and dysuria in combination with urgency (81%, 95% CI 72; 88). Seventy-one percent of the women who fulfilled the symptom criteria received an antibiotic prescription directly, 87% of these had a positive culture. The drug of choice was pivmecillinam for women (51%) and quinolones (50%) for men. The treatment duration was too long for the women; 68% were treated for ≥7 days. In conclusion, the adherence to national guidelines/recommendations was inadequate. To reduce the selection of multiresistant bacteria, an improvement of the use of diagnostic criteria/tools and antibiotic drugs in primary care is necessary.

Incidence, severity, help seeking, and management of uncomplicated urinary tract infection: a population-based survey

BACKGROUND

Limited knowledge of the population incidence and management of uncomplicated urinary tract infection (UTI) limits information provision and interventions to enhance care in the community.

AIM

To describe incidence and severity, help seeking, and management of UTI from a population perspective.

DESIGN AND SETTING

Household survey in England in 2014.

METHOD

In total, a random sample of 2424 females aged ≥16 years were interviewed in their own homes using computer-assisted interviewing about their UTI symptoms, help seeking, and management. Data were weighted by sex, age, ethnicity, working status, social grade, and housing tenure, and Government Office Region to be broadly representative of the general population.

RESULTS

Of the females interviewed, 892 (37%) reported having had at least one UTI in their lifetime (29% had more than one episode). In the past year, 11% of all females reported a UTI and 3% recurrent UTI (≥3 or more). Of those who had ever had a UTI, 48% rated their last UTI as fairly or very severe. In total, 95% consulted a health professional; 65% at their local GP practice during routine consulting hours. Out-of-hours consulting was uncommon but more prevalent in younger females. Of those contacting a health professional, 76% had a urine test, 74% were prescribed an antibiotic, but only 63% of these reported taking the antibiotic. Delayed antibiotic prescribing was rare.

CONCLUSION

UTI symptoms are common; most females consult in general practice, and are prescribed antibiotics, but one-third report not taking the antibiotics as prescribed. Benefit and harms in those taking, and not taking, antibiotics need to be better understood in order to improve help seeking, management, and adherence. Urine tests and antibiotics could be reduced by basing empirical antibiotics on symptoms, and increasing use of back-up prescriptions.

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.

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.

Abnormal urinalysis results are common, regardless of specimen collection technique, in women without urinary tract infections

BACKGROUND

Voided urinalysis to test for urinary tract infection (UTI) is prone to false-positive results for a number of reasons. Specimens are often collected at triage from women with any abdominal complaint, creating a low UTI prevalence population. Improper collection technique by the patient may affect the result. At least four indices, if positive, can indicate UTI.

OBJECTIVE

We examine the impact of voided specimen collection technique on urinalysis indicators of UTI and on urine culture contamination in disease-free women.

METHODS

In this crossover design, 40 menstrual-age female emergency department staff without UTI symptoms collected urine two ways: directly in a cup ("non-clean") and midstream clean catch ("ideal"). Samples underwent standard automated urinalysis and culture. Urinalysis indices and culture contamination were compared.

RESULTS

The proportion of abnormal results from samples collected by "non-clean" vs. "ideal" technique, respectively, were: leukocyte esterase (>trace) 50%, 35% (95% confidence interval for difference -6% to 36%); nitrites (any) 2.5%, 2.5% (difference -2.5 to 2.5%); white blood cells (>5/high-powered field [HPF]) 50%, 27.5% (difference 4 to 41%); bacteria (any/HPF) 77.5%, 62.5%, (difference -7 to 37%); epithelial cells (>few) 65%, 30% (difference 13 to 56%); culture contamination (>1000 colony-forming units of commensal or >2 species) 77%, 63% (difference -5 to 35%). No urinalysis index was positively correlated with culture contamination.

CONCLUSION

Contemporary automated urinalysis indices were often abnormal in a disease-free population of women, even using ideal collection technique. In clinical practice, such false-positive results could lead to false-positive UTI diagnosis. Only urine nitrite showed a high specificity. Culture contamination was common regardless of collection technique and was not predicted by urinalysis results.

Antibiotic treatment of acute uncomplicated cystitis based on rapid urine test and local epidemiology: lessons from a primary care series

Background

Acute uncomplicated cystitis (AUC) is an ideal target of optimization for antibiotic therapy in primary care. Because surveillance networks on urinary tract infections (UTI) mix complicated and uncomplicated UTI, reliable epidemiological data on AUC lack. Whether the antibiotic choice should be guided by a rapid urine test (RUT) for leukocytes and nitrites has not been extensively studied in daily practice. The aim of this primary care study was to investigate local epidemiology and RUT-daily use to determine the optimal strategy.

Methods

General practitioners included 18–65 years women with symptoms of AUC, performed a RUT and sent urines for analysis at a central laboratory. Different treatment strategies were simulated based on RUT and resistance results.

Results

Among 347 enrolled patients, 78% had a positive urine culture. Escherichia coli predominated (71%) with high rates of susceptibility to nitrofurantoin (100%), fosfomycin (99%), ofloxacin (97%), and even pivmecillinam (87%) and trimethoprim-sulfamethoxazole (87%). Modelization showed that the systematic use of RUT would reduce by 10% the number of patients treated. Fosfomycin for patients with positive RUT offered a 90% overall bacterial coverage, compared to 98% for nitrofurantoin. 95% for ofloxacin, 86% for trimethoprim-sulfamethoxazole and 78% for pivmecillinam.

Conclusion

Local epidemiology surveillance data not biased by complicated UTI demonstrates that the worldwide increase in antibiotic resistance has not affected AUC yet. Fosfomycin first line in all patients with positive RUT seems the best treatment strategy for AUC, combining good bacterial coverage with expected low toxicity and limited effect on fecal flora.

Trial registration

The current study was registered at clinicaltrials.gov (NCT00958295)

Diagnostic approach to urinary tract infections in male general practice patients: a national surveillance study

BACKGROUND

Diagnostic urinary tract infection (UTI) studies have primarily been performed among female patients.

AIM

To create a diagnostic algorithm for male general practice patients suspected of UTI.

DESIGN AND SETTING

Surveillance study in the Dutch Sentinel General Practice Network.

METHOD

Clinical information and dipstick results were collected from 603 patients. Algorithm-predicted care was compared with care as usual in terms of sensitivity (antibiotic recommended when UTI was confirmed) and specificity (no antibiotic recommended when no UTI was observed).

RESULTS

Complete information was available from 490/603 (81%) males, of whom 66% (321/490) had a UTI. A diagnostic algorithm recommending antimicrobial prescription in the case of a positive nitrite test or a positive leukocyte esterase test in males aged ≥60 years, had a positive predictive value (PPV) of 83% (95% confidence interval [CI] = 78 to 87) and a negative predictive value (NPV) of 60% (95% CI = 52 to 66), respectively (area under the ROC curve: 0.78, 95% CI = 0.74 to 0.82). When both dipstick results were positive in males aged ≥60 years, PPV increased to 90% (95% CI = 83 to 94), whereas NPV was highest in males <60 years with negative dipstick results (71%, 95% CI = 59 to 81). Sensitivity and specificity of predicted UTI care and usual care did not differ (75% versus 79%, P = 0.30, and 70% versus 63%, P = 0.17, respectively).

CONCLUSION

UTI care provided to Dutch male GP patients is as accurate as predicted care from a diagnostic algorithm. The studied clinical information and dipstick tests are useful for ruling in UTI in males, but have limited value in ruling out this diagnosis.

Management of urinary tract infections in the era of increasing antimicrobial resistance

Antimicrobial resistance of urinary pathogens is increasing. Most urinary tract infections (UTIs) should still be treated empirically. However, patients with recurrence or other risk factors for resistance may benefit from urine culture. Patients with recurrent UTI often resort to antibiotic prevention, a risky proposition in terms of resistance. Non-antimicrobial preventative methods should be considered first. If preventative antibiotics must be used, postcoital patient-initiated protocols are effective and reduce overall antibiotic exposure compared with continuous prophylaxis. Consider referring patients for urologic evaluation when at risk for complicated UTIs or when recurrence continues despite conservative interventions.

Can routine automated urinalysis reduce culture requests?

OBJECTIVES

There are a substantial number of unnecessary urine culture requests. We aimed to investigate whether urine dipstick and microscopy results could accurately rule out urinary tract infection (UTI) without urine culture.

DESIGN AND METHODS

The study included a total of 32,998 patients (11,928 men and 21,070 women, mean age: 39 ± 32 years) with a preliminary diagnosis of UTI and both urinalysis and urinary culture were requested. All urine cultures were retrospectively reviewed; association of culture positivity with a positive urinalysis result for leukocyte esterase (LE) and nitrite in chemical analysis and pyuria (WBC) and bacteriuria in microscopy was determined. Diagnostic performance of urinalysis parameters for detection of UTI was evaluated.

RESULTS

In total, 758 (2.3%) patients were positive by urine culture. Out of these culture positive samples, ratios of positive dipstick results for LE and nitrite were 71.0% (n=538) and 17.7% (n=134), respectively. The positive microscopy results for WBC and bacteria were 68.2% (n=517) and 78.8% (n=597), respectively. Negative predictive values for LE, nitrite, bacteriuria and WBC were very close to 100%.

CONCLUSIONS

Most of the samples have no or insignificant bacterial growth. Urine dipstick and microscopy can accurately rule out UTI. Automated urinalysis is a practicable and faster screening test which may prevent unnecessary culture requests for majority of patients.