Deconstructing the urinalysis: A novel approach to diagnostic and antimicrobial stewardship

Guidelines for the Prevention, Diagnosis, and Management of Urinary Tract Infections in Pediatrics and Adults: A WikiGuidelines Group Consensus Statement

Importance

Traditional approaches to practice guidelines frequently result in dissociation between strength of recommendation and quality of evidence.

Objective

To create a clinical guideline for the diagnosis and management of urinary tract infections that addresses the gap between the evidence and recommendation strength.

Evidence Review

This consensus statement and systematic review applied an approach previously established by the WikiGuidelines Group to construct collaborative clinical guidelines. In May 2023, new and existing members were solicited for questions on urinary tract infection prevention, diagnosis, and management. For each topic, literature searches were conducted up until early 2024 in any language. Evidence was reported according to the WikiGuidelines charter: clear recommendations were established only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were developed discussing the available literature and associated risks and benefits of various approaches.

Findings

A total of 54 members representing 12 countries reviewed 914 articles and submitted information relevant to 5 sections: prophylaxis and prevention (7 questions), diagnosis and diagnostic stewardship (7 questions), empirical treatment (3 questions), definitive treatment and antimicrobial stewardship (10 questions), and special populations and genitourinary syndromes (10 questions). Of 37 unique questions, a clear recommendation could be provided for 6 questions. In 3 of the remaining questions, a clear recommendation could only be provided for certain aspects of the question. Clinical reviews were generated for the remaining questions and aspects of questions not meeting criteria for a clear recommendation.

Conclusions and Relevance

In this consensus statement that applied the WikiGuidelines method for clinical guideline development, the majority of topics relating to prevention, diagnosis, and treatment of urinary tract infections lack high-quality prospective data and clear recommendations could not be made. Randomized clinical trials are underway to address some of these gaps; however further research is of utmost importance to inform true evidence-based, rather than eminence-based practice.

A Cross-Sectional Survey to Identify Sociodemographic Factors Associated with the Frequency of Urinalysis in a Representative Sample of Adults in Poland, 2024

A general urine test is considered one of the basic diagnostic tests using in healthcare. This study aimed to analyze sociodemographic factors associated with the frequency of urine testing in Poland. This cross-sectional survey was conducted using computer-assisted web interviewing (CAWI) between 1 March and 4 March 2024. A representative sample of 1113 adults in Poland (aged 18-86 years, 52.5% of whom were females) took part in the study. The survey showed that 46.3% of adults in Poland had a urinalysis in the last 12 months. One-fifth (20.7%) of the participants had a urinalysis more than a year ago but not more than 2 years ago. Moreover, 26.7% had a urinalysis performed 2-3 years ago. Among all participants, female gender (OR = 1.31 [1.01-1.68]; p < 0.05), being aged 70 years and over (OR = 2.22 [1.23-4.02]; p < 0.01), having children (OR = 1.45 [1.01-2.09]; p < 0.05), and having urologic diseases (OR = 2.34 [1.79-3.02]; p < 0.001) were significantly associated with having urinalysis in the last 12 months. Among respondents without urologic diseases, female gender (OR = 1.33 [1.02-1.74]; p < 0.05), being aged 60 years and over (p < 0.05), and being married (OR = 1.45 [1.09-1.94]; p < 0.05) were significantly associated with having a urinalysis in the last 12 months. There was no significant impact of educational level, occupational status, or financial situation on the frequency of urinalysis.

Reprint of: Impact of altered mental status on antibiotic prescribing and outcomes in hospitalized patients presenting with pyuria

BACKGROUND

Pyuria is nonspecific and may result in over-treatment of asymptomatic bacteriuria (ASB). The Infectious Diseases Society of America recommends against antibiotic treatment of ASB for most patients including those presenting with altered mental status (AMS). Close observation is recommended over treatment to avoid missing alternative causes of AMS and overuse of antibiotics resulting in adverse events and resistance.

OBJECTIVES

The purpose of this study was to evaluate patient outcomes associated with antibiotic treatment of pyuria in patients presenting with AMS at hospital admission without specific urinary tract infection (UTI) symptoms. The primary objective was to compare 30-day readmission rates of patients with pyuria and AMS treated with antibiotics (AMS+Tx) versus those who were not treated (AMS-NoTx). Secondary outcomes included identifying risk factors for antibiotic treatment, comparing alternative diagnoses for AMS, and comparing safety outcomes.

METHODS

This retrospective cohort study evaluated adult patients with AMS and pyuria (10 WBC/hpf) admitted between February 1, 2020 and October 1, 2021, in a 350-bed community teaching hospital. Patients with documented urinary symptoms were excluded. Additional exclusion criteria included admission to critical care, history of renal transplant, urological surgery, coinfections, pregnancy, and neutropenia.

RESULTS

Two-hundred patients were included (AMS+Tx, n = 162; AMS-NoTx, n=38). There was no difference in 30-day hospital readmission rate for AMS between groups (AMS+Tx 16.7% vs AMS-NoTx 23.7%, P = 0.311). An alternative diagnosis of AMS occurred more frequently when antibiotics were withheld (AMS+Tx 66% vs. AMS-NoTx 86.8%, P = 0.012). Urinalyses showing bacteria (odds ratio 2.52; 95% CI, 1.11-5.731) and positive urine culture (OR 3.36; 95% CI, 1.46-7.711) were associated with antibiotic prescribing.

CONCLUSIONS

Inappropriate antibiotic use is common among hospitalized patients presenting with AMS and pyuria; however, treatment of asymptomatic pyuria did not decrease rates of subsequent readmission for AMS or retreatment of symptomatic UTI. Patients who were monitored off antibiotics had higher rates of alternative AMS diagnosis.

Sticker-Type Remote Monitoring System for Early Risk Detection of Catheter Associated Urinary Tract Infections

A substantial number of critically ill patients in intensive care units (ICUs) rely on indwelling urinary catheters (IDCs), demanding regular monitoring of urine bags. This process increases the workload for healthcare providers and elevates the risk of exposure to contagious diseases. Moreover, IDCs are a primary cause of catheter-associated urinary tract infections (UTIs) in ICU patients whose delayed detection can have life-threatening complications. To address this, we have developed a Sticker Type Antenna for Remote Sensing (STARS) system capable of measuring urine flow rate and conductivity as early-risk markers for UTIs, alongside tracking patients' urine bag status to facilitate medical automation for healthcare providers. STARS comprises a simple, low-cost, disposable antenna module for contactless measurements of urine volume and conductivity, and a reusable wireless module for real-time data transmission. Systematic studies on STARS revealed its stable performance within physiologically relevant ranges of urine volume (0 to 2000 ml) and conductivity (5 to 40 mS/cm) in urine bags. As a proof-of-concept, STARS was tested in artificially created healthy and infected urine specimens to validate its non-contact sensing performance in detecting the onset of UTIs in catheterized patients within a hospital-like environment. STARS represents the first application of a real-time, contactless, wireless monitoring platform for simultaneous urine bag management and early risk detection of UTIs.

Diagnostic Stewardship for Urine Cultures

Urinary tract infections are among the most common infectious diagnoses in health care, but most urinary tract infections are diagnosed inappropriately in patients without signs or symptoms of infection. Asymptomatic bacteriuria leads to inappropriate antibiotic prescribing and negative downstream effects, including antimicrobial resistance, health care-associated infections, and adverse drug events. Diagnostic stewardship is the process of modifying the ordering, performing, or reporting of test results to improve clinical care. Diagnostic stewardship impacts the diagnostic pathway to decrease inappropriate detection and treatment of asymptomatic bacteriuria. This article reviews diagnostic stewardship methods and closes with a case study illustrating these principles in practice.

Laboratory Tests, Bacterial Resistance, and Treatment Options in Adult Patients Hospitalized with a Suspected Urinary Tract Infection

Patients treated for systemic urinary tract infections commonly have nonspecific presentations, and the specificity of the results of the urinalysis and urine cultures is low. In the following narrative review, we will describe the widespread misuse of urine testing, and consider how to limit testing, the disutility of urine cultures, and the use of antibiotics in hospitalized adult patients. Automated dipstick testing is more precise and sensitive than the microscopic urinalysis which will result in false negative test results if ordered to confirm a positive dipstick test result. There is evidence that canceling urine cultures if the dipstick is negative (negative leukocyte esterase, and nitrite) is safe and helps prevent the overuse of urine cultures. Because of the side effects of introducing a urine catheter, for patients who cannot provide a urine sample, empiric antibiotic treatment should be considered as an alternative to culturing the urine if a trial of withholding antibiotic therapy is not an option. Treatment options that will decrease both narrower and wider spectrum antibiotic use include a period of watching and waiting before antibiotic therapy and empiric treatment with antibiotics that have resistance rates > 10%. Further studies are warranted to show the option that maximizes patient comfort and safety.

Alternative Strategies to Provide Actionable Results When a Supply of Urinalysis Strips Is Unavailable

CONTEXT.—

Urinalysis instrument-specific dip strips offer physicians qualitative results for actionable analytes (protein, glucose, leukocyte esterase, nitrates, hemoglobin, and ketones).

OBJECTIVE.—

To explain a strategy implemented to support clinical decision-making by providing urine quantification of protein, glucose, white blood cells (WBCs), and red blood cells because of urine strip shortages.

DESIGN.—

During shortages, we implemented an automated algorithm that triggered sending urine samples to the automation line for quantification of protein and glucose and ensured that urine microscopy was performed to obtain WBC and red blood cell counts. The algorithm printed 2 labels so nursing staff would collect 2 specimens. We monitored the turnaround time from the specimen being received in the laboratory to result verification, ensured that the culture reflex order was triggered, and tracked complaints by physicians regarding not having usual urinalysis results. Prior to implementation, correlation between sample types for protein and glucose measurement was found acceptable.

RESULTS.—

The algorithm was put in place twice during 2022. The turnaround time of urine microscopic study was identical to that obtained when the urinalysis was done with the strips; however, the quantification of glucose and protein took approximately 30 minutes more. Urine reflex cultures were triggered correctly with the algorithm, as they were derived entirely from a WBC count higher than 10 per high-power field. During the shortage period we had only 1 complaint, by a physician wanting to have results of nitrates.

CONCLUSIONS.—

During urine strip shortages, we successfully implemented a diversion algorithm that provided actionable urinalysis analytes in a timely manner with minimal provider complaints.

De-implementation strategy to reduce overtreatment of asymptomatic bacteriuria in the emergency department: a stepped-wedge cluster randomised trial

Background

Asymptomatic bacteriuria (ASB) is the presence of bacteria in the urine of patients without symptoms of a urinary tract infection. Generally, treating ASB is not beneficial.

Objective

We aimed to reduce overtreatment of ASB in the emergency department (ED) through a multifaceted de-implementation strategy.

Design

A stepped-wedge cluster randomised trial.

Methods

We performed our study in five EDs in the Netherlands from December 2020 to December 2021. Adult patients with urine cultures obtained during ED presentation were screened for inclusion and we excluded patients with indications for antibiotic therapy. The de-implementation strategy included education, reminders and competitive feedback on baseline results. The primary endpoint was patients with ASB treated with antibiotics. Secondary endpoints included the treatment duration and the number of urine tests ordered (urinalyses and urine cultures) in the ED per 1000 adult patients.

Results

In total, 6837 urine cultures were screened. ASB was present in 224/3289 (7%) and 201/3548 (6%) patients, from whom 65/224 (29%) and 46/201 (23%) were inappropriately treated with antibiotics in the baseline and intervention period, respectively (adjusted odds ratio 1.20, 95% CI 0.56-2.62, p = 0.65). The number of urinalyses ordered decreased from 182 to 153 per 1000 patients (incidence rate difference -29.10, 95% CI -46.36 to -11.78, p < 0.001). Further, the treatment duration was shortened for patients with ASB in the intervention period (baseline period: 7.98 days (standard deviation (SD) 4.31) vs 5.79 days (SD 3.33), p = 0.006).

Conclusion

Diagnostic stewardship by our de-implementation strategy reduced the number of urinalyses ordered and treatment duration in the ED, but we found no significant reduction in overtreatment of ASB.

Trial registration

The trial was registered at https://onderzoekmetmensen.nl/en/trial/25918, on 17-12-2019, registration number NL8242. The first participants were enrolled on 01-12-2020.

Profile, Risk Factors, and Outcomes of Asymptomatic Bacteriuria in Kidney Transplant Recipients with Normal Pretransplant Genitourinary Tract: A Single-Center Experience

Introduction

There is a paucity of studies on asymptomatic bacteriuria (ASB) among kidney transplant recipients (KTR) in developing countries. This study assessed the clinical profile, risk factors, outcomes, and impact of treatment of ASB in KTRs with a normal genitourinary tract.

Methods

Consecutive KTRs from 2009 to 2018 with no clinical or radiological evidence of obstructive uropathy were included. Urinary tract infection (UTI) after ASB was defined as occurrence of cystitis, pyelonephritis, or urosepsis, with ASB being the first bacteriuric episode.

Results

Seven hundred ten out of 794 patients with median follow up of 47 months were included. The mean age was 35.5 ± 12 years. Eighty-one patients (11.4%) developed ASB at a median of 25 days (IQR 10, 134.5). Fifty-three percent and 4.9% of ASB episodes were extended-spectrum beta-lactamase (ESBL) positive and carbapenem-resistant organisms, respectively. Eighteen patients (32.1%) with early ASB (<3 months) and 5 (20%) with late ASB developed UTI on follow-up. Fifty-five percent of early and 16% of late ASB episodes were treated, with no significant difference observed in the risk of development of UTI when compared to untreated ASB episodes.

Conclusion

The incidence of ASB as first bacteriuric episode in our cohort was 11.4%, with there being significant antimicrobial resistance. Female gender, pretransplant UTI, and delayed graft function were independently associated with development of ASB. Treatment of ASB episodes either early or late did not decrease the risk of development of UTI.

Antimicrobial Stewardship in Immunocompromised Patients: Current State and Future Opportunities

Immunocompromised (IC) patients are high risk for complications due to a high rate of antibiotic exposure. Antimicrobial stewardship interventions targeted to IC patients can be challenging due to limited data in this population and a high risk of severe infection-related outcomes. Here, the authors review immunocompromised antimicrobial stewardship barriers, metrics, and opportunities for antimicrobial use and testing optimization. Last, the authors highlight future steps in the field.

Improving antimicrobial use through better diagnosis: The relationship between diagnostic stewardship and antimicrobial stewardship

Antimicrobial stewardship programs (ASPs) exist to optimize antibiotic use, reduce selection for antimicrobial-resistant microorganisms, and improve patient outcomes. Rapid and accurate diagnosis is essential to optimal antibiotic use. Because diagnostic testing plays a significant role in diagnosing patients, it has one of the strongest influences on clinician antibiotic prescribing behaviors. Diagnostic stewardship, consequently, has emerged to improve clinician diagnostic testing and test result interpretation. Antimicrobial stewardship and diagnostic stewardship share common goals and are synergistic when used together. Although ASP requires a relationship with clinicians and focuses on person-to-person communication, diagnostic stewardship centers on a relationship with the laboratory and hardwiring testing changes into laboratory processes and the electronic health record. Here, we discuss how diagnostic stewardship can optimize the "Four Moments of Antibiotic Decision Making" created by the Agency for Healthcare Research and Quality and work synergistically with ASPs.

Antibiotic management of urinary tract infections in the post-antibiotic era: a narrative review highlighting diagnostic and antimicrobial stewardship

BACKGROUND

As one of the most common indications for antimicrobial prescription in the community, the management of urinary tract infections (UTIs) is both complicated by, and a driver of, antimicrobial resistance.

OBJECTIVES

To highlight the key clinical decisions involved in the diagnosis and treatment of UTIs in adult women, focusing on clinical effectiveness and both diagnostic and antimicrobial stewardship as we approach the post-antimicrobial era.

SOURCES

Literature reviewed via directed PubMed searches and manual searching of the reference list for included studies to identify key references to respond to the objectives. A strict time limit was not applied. We prioritised recent publications, randomised trials, and systematic reviews (with or without meta-analyses) where available. Searches were limited to English language articles. A formal quality assessment was not performed; however, the strengths and limitations of each paper were reviewed by the authors throughout the preparation of this manuscript.

CONTENT

We discuss the management of UTIs in ambulatory adult women, with particular focus on uncomplicated infections. We address the diagnosis of UTIs, including the following: definition and categorisation; bedside assessments and point-of-care tests; and the indications for, and use of, laboratory tests. We then discuss the treatment of UTIs, including the following: indications for treatment, antimicrobial sparing approaches, key considerations when selecting a specific antimicrobial agent, specific treatment scenarios, and duration of treatment. We finally outline emerging areas of interest in this field.

IMPLICATIONS

The steady increase in antimicrobial resistance among common uropathogens has had a substantial affect on the management of UTIs. Regarding both diagnosis and treatment, the clinician must consider both the patient (clinical effectiveness and adverse effects, including collateral damage) and the community more broadly (population-level antimicrobial selection pressure).

Optimizing reflex urine cultures: Using a population-specific approach to diagnostic stewardship

BACKGROUND

Clinicians and laboratories routinely use urinalysis (UA) parameters to determine whether antimicrobial treatment and/or urine cultures are needed. Yet the performance of individual UA parameters and common thresholds for action are not well defined and may vary across different patient populations.

METHODS

In this retrospective cohort study, we included all encounters with UAs ordered 24 hours prior to a urine culture between 2015 and 2020 at 3 North Carolina hospitals. We evaluated the performance of relevant UA parameters as potential outcome predictors, including sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV). We also combined 18 different UA criteria and used receiver operating curves to identify the 5 best-performing models for predicting significant bacteriuria (≥100,000 colony-forming units of bacteria/mL).

RESULTS

In 221,933 encounters during the 6-year study period, no single UA parameter had both high sensitivity and high specificity in predicting bacteriuria. Absence of leukocyte esterase and pyuria had a high NPV for significant bacteriuria. Combined UA parameters did not perform better than pyuria alone with regard to NPV. The high NPV ≥0.90 of pyuria was maintained among most patient subgroups except females aged ≥65 years and patients with indwelling catheters.

CONCLUSION

When used as a part of a diagnostic workup, UA parameters should be leveraged for their NPV instead of sensitivity. Because many laboratories and hospitals use reflex urine culture algorithms, their workflow should include clinical decision support and or education to target symptomatic patients and focus on populations where absence of pyuria has high NPV.

A Baker's Dozen of Top Antimicrobial Stewardship Intervention Publications for Hospitalized Patients in 2021

Keeping abreast of the antimicrobial stewardship-related articles published each year is challenging. The Southeastern Research Group Endeavor (SERGE-45) identified antimicrobial stewardship-related, peer-reviewed literature that detailed an "actionable" intervention among hospitalized populations during 2021. The top 13 publications were selected using a modified Delphi technique. These manuscripts were reviewed to highlight "actionable" interventions used by antimicrobial stewardship programs in hospitalized populations to capture potentially effective strategies for local implementation.

Why Are We Frequently Ordering Urinalyses in Patients without Symptoms of Urinary Tract Infections in the Emergency Department?

(1) Background: In the emergency department (ED), ordering urine tests in patients without symptoms of a urinary tract infection can lead to inappropriate antimicrobial treatment. We aimed to identify factors contributing to the unnecessary ordering of urinalyses in the ED. (2) Methods: An online survey study among nurses and physicians working in the EDs of five hospitals in the Netherlands was conducted. (3) Results: The overall response rate was 26% (221/850; 85 nurses and 136 physicians). The vast majority of the respondents reported knowing when to order urine tests (197/221; 90%). Almost two-thirds of the respondents (145/221; 66%) agreed that they ordered urinalyses because it is rapid and non-invasive to patients. Most nurses (66/86; 78%) said they informed the doctor if they thought the urine test would not contribute to the patient's diagnosis, but only one-third of the physicians agreed with this statement (44/136; 32%). Most respondents (160/221; 72%) thought guidelines or protocols about urinalyses in the ED would be functional. (4) Conclusions: These results suggest urinalyses were frequently ordered in the ED to achieve a fast work process. Nurses and physicians could improve their communication about the indications for urine tests. Developing diagnostic guidelines for urine testing may be convenient.

Predictive System Implementation to Improve the Accuracy of Urine Self-Diagnosis with Smartphones: Application of a Confusion Matrix-Based Learning Model through RGB Semiquantitative Analysis

Urinalysis, an elementary chemical reaction-based method for analyzing color conversion factors, facilitates examination of pathological conditions in the human body. Recently, considerable urinalysis-centered research has been conducted on the analysis of urine dipstick colors using smartphone cameras; however, such methods have a drawback: the problem of reproducibility of accuracy through quantitative analysis. In this study, to solve this problem, the function values for each concentration of a range of analysis factors were implemented in an algorithm through urine dipstick RGB semi-quantitative color analysis to enable real-time results. Herein, pH, glucose, ketones, hemoglobin, bilirubin, protein (albumin), and nitrites were selected as analysis factors, and the accuracy levels of the existing equipment and the test application were compared and evaluated using artificial urine. In the semi-quantitative analysis, the red (R), green (G), and blue (B) characteristic values were analyzed by extracting the RGB characteristic values of the analysis factors for each concentration of artificial urine and obtaining linear function values. In addition, to improve the reproducibility of detection accuracy, the measurement value of the existing test equipment was set to an absolute value; using a machine-learning technique, the confusion matrix, we attempted to stabilize test results that vary with environment.

Top Myths of Diagnosis and Management of Infectious Diseases in Hospital Medicine

Antimicrobial agents are among the most frequently prescribed medications during hospitalization. However, approximately 30% to 50% or more of inpatient antimicrobial use is unnecessary or suboptimal. Herein, we describe 10 common myths of diagnosis and management that often occur in the hospital setting. Further, we discuss supporting data to dispel each of these myths. This analysis will provide hospitalists and other clinicians with a foundation for rational decision-making about antimicrobial use and support antimicrobial stewardship efforts at both the patient and institutional levels.

Combined Training Intervention Targeting Medical and Nursing Staff Reduces Ciprofloxacin Use and Events of Urinary Tract Infection

Inappropriate diagnosis of urinary tract infections (UTI) contributes to antimicrobial overuse. A combined training intervention for medical and nursing staff mainly addressing the analytic process reduced UTI events (9.20 vs. 7.36 per 1000 PD, −20.0%, p = 0.003) and the utilization rate of ciprofloxacin (11.6 vs. 3.5, −69.6 p = 0.001) in a Bavarian University Hospital. Combined training intervention—as part of an antibiotic stewardship program—can be effective in avoiding unnecessary urinalysis and reducing antibiotic consumption.

Opportunities for antibiotic stewardship in emergency department or hospitalized patients with asymptomatic bacteriuria: identifying risk factors for antibiotic treatment

Antibiotic treatment of asymptomatic bacteriuria (ASB) is considered inappropriate and may lead to adverse events. This 2-center, retrospective cohort study including emergency department or inpatient adults identified pyuria (odds ratio, 2.43; 95% confidence interval, 1.17–5.01; P = .02) as the only independent risk factor for antibiotic treatment of ASB.

Quality Improvement Interventions and Implementation Strategies for Urine Culture Stewardship in the Acute Care Setting: Advances and Challenges

PURPOSE OF REVIEW

The goal of this article is to highlight how and why urinalyses and urine cultures are misused, review quality improvement interventions to optimize urine culture utilization, and highlight how to implement successful, sustainable interventions to improve urine culture practices in the acute care setting.

RECENT FINDINGS

Quality improvement initiatives aimed at reducing inappropriate treatment of asymptomatic bacteriuria often focus on optimizing urine test utilization (i.e., urine culture stewardship). Urine culture stewardship interventions in acute care hospitals span the spectrum of quality improvement initiatives, ranging from strong systems-based interventions like suppression of urine culture results to weaker interventions that focus on clinician education alone. While most urine culture stewardship interventions have met with some success, overall results are mixed, and implementation strategies to improve sustainability are not well understood.

SUMMARY

Successful diagnostic stewardship interventions are based on an assessment of underlying key drivers and focus on multifaceted and complementary approaches. Individual intervention components have varying impacts on effectiveness, provider autonomy, and sustainability. The best urine culture stewardship strategies ultimately include both technical and socio-adaptive components with long-term, iterative feedback required for sustainability.