New markers of urinary tract infection

Point of care testing for the diagnosis of periprosthetic joint infections: a review

BACKGROUND

Periprosthetic joint infection (PJI) remains a major complication following total joint arthroplasties (TJA), significantly affecting patient outcomes and healthcare costs. Despite advances in diagnostic techniques, challenges persist in accurately diagnosing PJI, underscoring the need for effective point-of-care testing (POCT).

METHODS

This review examines the current literature and latest developments in POCT for diagnosing PJI, focusing on biomarkers such as alpha-defensin, leukocyte esterase, calprotectin, and C-reactive protein (CRP). Criteria from various societies like the Musculoskeletal Infection Society, Infectious Diseases Society of America, and the International Consensus Meeting were compared to evaluate the effectiveness of these biomarkers in a point-of-care setting.

RESULTS

POCT provides rapid results essential for the timely management of PJI, with alpha-defensin and leukocyte esterase showing high specificity and sensitivity. Recent advancements have introduced novel biomarkers like calprotectin, which demonstrate high diagnostic accuracy. However, challenges such as the variability in test performance and the need for validation under different clinical scenarios remain.

DISCUSSION

While POCT for PJI shows promising results, their integration into clinical practice requires standardized protocols and further validation. The evolution of these diagnostic tools offers a potential shift toward more personalized and immediate care, potentially improving outcomes for patients undergoing TJA.

Urinary calprotectin as a diagnostic tool for detecting significant bacteriuria

Pyuria in dipstick examination serves as the most widespread screening tool for urinary tract infections (UTI). The absence of pyuria, however, does not exclude UTI. We investigated the diagnostic value of urinary calprotectin, a mediator protein of the innate immune system, which is released by leukocytes, for the detection of UTI and compared it with dipstick pyuria. Since even low numbers of leukocytes in the urine significantly increase urinary calprotectin concentrations, calprotectin might be a more sensitive marker than pyuria detected by dipstick. All 162 patients were prospectively included and underwent a urine dipstick, urine culture, quantification of proteinuria and determination of calprotectin in the urine. Urinary calprotectin was determined using an enzyme-linked immunosorbent assay (ELISA). UTI was defined as urine cultures with detection of one or a maximum of two uropathogenic bacteria with ≥ 105 colony-forming units per millilitre (CFU/ml). Exclusion criteria were acute kidney injury, chronic renal insufficiency and tumors of the urinary tract. 71 (43.8%) patients had a UTI. Of the 91 patients without UTI, 23 had a contamination and 19 had evidence of ≥ 105 CFU/ml considered to be asymptomatic bacteriuria. The median calprotectin concentration in patients with UTI and pyuria was significantly higher than in patients with UTI and without pyuria (5510.4 vs. 544.7 ng/ml). In ROC analyses, calprotectin revealed an area under the curve (AUC) of 0.70 for the detection of significant bacteriuria. Pyuria in dipstick examinations provided an AUC of 0.71. There was no significant difference between these AUCs in the DeLong test (p = 0.9). In patients with evidence of significant bacteriuria but without pyuria, a significantly higher calprotectin concentration was measured in the urine than in patients with neither pyuria nor UTI (544.7 ng/ml vs 95.6 ng/ml, p = 0.029). Urinary calprotectin is non-inferior to dipstick pyuria in the detection of UTI.

Perimenopausal syndrome and hypertension during perimenopause in South China: prevalence, relationships and risk factors

BACKGROUND

More than 2 billion women are experiencing the menopausal transition in China, and some of these women have hypertension. Limited studies has focused on perimenopausal syndrome and hypertension in a specific population, so we aimed to investigate the prevalence of perimenopausal syndrome and hypertension and to analyse their relationships and risk factors in perimenopausal women in South China.

METHODS

This cross-sectional study included 3553 women aged 40 to 60 years from South China. We collected medical report, lifestyle, blood sample, general condition questionnaire, and modified Kupperman index (mKMI) data. Multivariate logistic regression analysis was performed to identify risk factors for perimenopausal syndrome and hypertension during perimenopause.

RESULTS

The prevalence of hypertension in perimenopause patients was 16.58%, and the prevalence of perimenopausal syndrome was 9.9%. Compared with women without hypertension during perimenopause, women with HTN during perimenopause had an increased risk of perimenopausal syndrome (26.4% vs. 8.7%, P < 0.001). Lipid levels and urinary tract infections were risk factors for hypertension and perimenopausal syndrome, in addition to the presence of breast nodules, the intake of snacks at night, high-salt diets, red meat and sugar-sweetened beverages, and a history of smoking and drinking for perimenopausal syndrome and the presence of gestational hypertension and diabetes for hypertension.

CONCLUSION

We concluded that perimenopausal syndrome and HTN are common in perimenopausal women in South China, and the associations between them are strong and positive. Perimenopausal syndrome shares some common risk factors with HTN during perimenopause, such as BMI and dyslipidaemia. Therefore, gynaecological endocrinologists in China should consider screening for perimenopausal syndrome in hypertensive perimenopausal women, and appropriate management of perimenopause is needed to alleviate these conditions.

Microfluidic systems for infectious disease diagnostics

Microorganisms, encompassing both uni- and multicellular entities, exhibit remarkable diversity as omnipresent life forms in nature. They play a pivotal role by supplying essential components for sustaining biological processes across diverse ecosystems, including higher host organisms. The complex interactions within the human gut microbiota are crucial for metabolic functions, immune responses, and biochemical signalling, particularly through the gut-brain axis. Viruses also play important roles in biological processes, for example by increasing genetic diversity through horizontal gene transfer when replicating inside living cells. On the other hand, infection of the human body by microbiological agents may lead to severe physiological disorders and diseases. Infectious diseases pose a significant burden on global healthcare systems, characterized by substantial variations in the epidemiological landscape. Fast spreading antibiotic resistance or uncontrolled outbreaks of communicable diseases are major challenges at present. Furthermore, delivering field-proven point-of-care diagnostic tools to the most severely affected populations in low-resource settings is particularly important and challenging. New paradigms and technological approaches enabling rapid and informed disease management need to be implemented. In this respect, infectious disease diagnostics taking advantage of microfluidic systems combined with integrated biosensor-based pathogen detection offers a host of innovative and promising solutions. In this review, we aim to outline recent activities and progress in the development of microfluidic diagnostic tools. Our literature research mainly covers the last 5 years. We will follow a classification scheme based on the human body systems primarily involved at the clinical level or on specific pathogen transmission modes. Important diseases, such as tuberculosis and malaria, will be addressed more extensively.

Applications of Artificial Intelligence in Urinalysis: Is the Future Already Here?

BACKGROUND

Artificial intelligence (AI) has emerged as a promising and transformative tool in the field of urinalysis, offering substantial potential for advancements in disease diagnosis and the development of predictive models for monitoring medical treatment responses.

CONTENT

Through an extensive examination of relevant literature, this narrative review illustrates the significance and applicability of AI models across the diverse application area of urinalysis. It encompasses automated urine test strip and sediment analysis, urinary tract infection screening, and the interpretation of complex biochemical signatures in urine, including the utilization of cutting-edge techniques such as mass spectrometry and molecular-based profiles.

SUMMARY

Retrospective studies consistently demonstrate good performance of AI models in urinalysis, showcasing their potential to revolutionize clinical practice. However, to comprehensively evaluate the real clinical value and efficacy of AI models, large-scale prospective studies are essential. Such studies hold the potential to enhance diagnostic accuracy, improve patient outcomes, and optimize medical treatment strategies. By bridging the gap between research and clinical implementation, AI can reshape the landscape of urinalysis, paving the way for more personalized and effective patient care.

Antibiotic prescription patterns in patients with suspected urinary tract infections in Ecuador

BACKGROUND

Urinary tract infections (UTI) are among the most common cause to prescribe antibiotics in primary care. Diagnosis is based on the presence of clinical symptoms in combination with the results of laboratory tests. Antibiotic therapy is the primary approach to the treatment of UTIs; however, some studies indicate that therapeutics in UTIs may be suboptimal, potentially leading to therapeutic failure and increased bacterial resistance.

METHODS

This study aimed to analyze the antibiotic prescription patterns in adult patients with suspected UTIs and to evaluate the appropriateness of the antibiotic prescription. This is a cross-sectional study of patients treated in outpatient centers and in a second-level hospital of the Ministry of Public Health (MOPH) in a city in Ecuador during 2019. The International Classification of Disease Tenth Revision (ICD-10) was used for the selection of the acute UTI cases. The patients included in this study were those treated by family, emergency, and internal medicine physicians.

RESULTS

We included a total of 507 patients in the analysis and 502 were prescribed antibiotics at first contact, constituting an immediate antibiotic prescription rate of 99.01%. Appropriate criteria for antibiotic prescription were met in 284 patients, representing an appropriate prescription rate of 56.02%. Less than 10% of patients with UTI had a urine culture. The most frequently prescribed antibiotics were alternative antibiotics (also known as second-line antibiotics), such as ciprofloxacin (50.39%) and cephalexin (23.55%). Factors associated with inappropriate antibiotic prescribing for UTIs were physician age over forty years, OR: 2.87 (95% CI, 1.65-5.12) p<0.0001, medical care by a general practitioner, OR: 1.89 (95% CI, 1.20-2.99) p = 0.006, not using point-of-care testing, OR: 1.96 (95% CI, 1.23-3.15) p = 0.005, and care at the first level of health, OR: 15.72 (95% CI, 8.57-30.88) p<0.0001.

CONCLUSIONS

The results of our study indicate an appropriate prescription rate of 56.02%. Recommended antibiotics such as nitrofurantoin and fosfomycin for UTIs are underutilized. The odds for inappropriate antibiotic prescription were 15.72 times higher at the first level of care compared to the second. Effective strategies are needed to improve the diagnosis and treatment of UTIs.

Electrochemical Diagnosis of Urinary Tract Infection Using Boron-Doped Diamond Electrodes

Efficient detection of sodium nitrite in human urine could be used to diagnose urinary tract infections rapidly. Here, we demonstrate a fast and novel method for the selective detection of sodium nitrite in different human urine samples using electrolysis with a bare boron-doped diamond electrode. The measurement is performed without adding any other species, such as enzymes, and uses a simple electrochemical approach with an oxidation step followed by reduction. In the present study, we pay attention to the reduction potential range for the measurement, which is substantially different from many previous literature reports that focus on the oxidation reaction. The determination of added sodium nitrite based on cyclic voltammetry or differential pulse voltammetry is employed for two pooled urine samples and three individual urine matrices. From this, the linear response ranges for sodium nitrite detection are 0.5-10 mg/L (7.2-140 μmol/L) and 10-400 mg/L (140-5800 μmol/L). The results from these urine samples convert well to the calibration curve, with a limit of detection established as 0.82 mg/L (R2 = 0.9914), which is clinically relevant.

Elevated UTI Biomarkers in Symptomatic Patients with Urine Microbial Densities of 10,000 CFU/mL Indicate a Lower Threshold for Diagnosing UTIs

The literature lacks consensus on the minimum microbial density required for diagnosing urinary tract infections (UTIs). This study categorized the microbial densities of urine specimens from symptomatic UTI patients aged ≥ 60 years and correlated them with detected levels of the immune response biomarkers neutrophil gelatinase-associated lipocalin (NGAL), interleukin-8 (IL-8), and interleukin-1-beta (IL-1β). The objective was to identify the microbial densities associated with significant elevation of these biomarkers in order to determine an optimal threshold for diagnosing symptomatic UTIs. Biobanked midstream voided urine samples were analyzed for microbial identification and quantification using standard urine culture (SUC) and multiplex-polymerase chain reaction (M-PCR) testing, while NGAL, IL-8, and IL-1β levels were measured via enzyme-linked immunosorbent assay (ELISA). NGAL, IL-8, and IL-1β levels were all significantly elevated at microbial densities ≥ 10,000 cells/mL when measured via M-PCR (p < 0.0069) or equivalent colony-forming units (CFUs)/mL via SUC (p < 0.0104) compared to samples with no detectable microbes. With both PCR and SUC, a consensus of two or more elevated biomarkers correlated well with microbial densities > 10,000 cells/mL or CFU/mL, respectively. The association between ≥10,000 cells and CFU per mL with elevated biomarkers in symptomatic patients suggests that this lower threshold may be more suitable than 100,000 CFU/mL for diagnosing UTIs.

Bacterial profile, antimicrobial resistance, and molecular detection of ESBL and quinolone resistance gene of uropathogens causing urinary tract infection in the southeastern part of Bangladesh

Humans frequently contract urinary tract infections (UTIs), which can be brought on by uropathogens (UPs) that are multi-drug resistant. Treatment for UTIs brought on by pathogenic UPs that produce extended-spectrum lactamases (ESBLs) is more costly and potentially fatal. As a result, the objective of this study was to use culture, biochemical, and 16S rRNA sequencing to identify and characterize UPs isolated from outpatients in Noakhali, Bangladesh, who had symptoms of UTIs. ESBL gene identification and quinolone resistance gene typing were then performed on the isolates using polymerase chain reaction (PCR). Throughout the trial's 8-month duration, 152 (76%) of 200 urine samples were positive for the presence of UPs. The overall number of UPs recovered was 210, with 39 individuals having multiple UPs present in their samples. Among all of the isolates, Escherichia coli (45.24%, 95/210; 95% confidence interval (CI): 35.15-57.60%), Enterobacter spp. (24.76%, 52/210; CI: 19.15-35.77%), Klebsiella spp. (20.95%; 44/210; CI: 15.15-30.20%), and Providencia spp. (9.05%; 19/210; CI: 4.95-19.25%) were the four most prevalent bacteria found in the isolates. The UPs displayed a very high level of resistance to piperacillin 96.92% (126/130), ampicillin 90% (117/130), nalidixic acid 77.69% (101/130), cefazolin 70% (91/130), amoxicillin 50% (55/130), cefazolin 42.31% (55/130), nitrofurantoin 43.08% (56/130), and ciprofloxacin 33.08% (43/130), whereas resistance to netilmicin (3.85%), amikacin (4.62%), and imipenem (9.23%) was low. Individually, every species of E. coli and Providencia spp. showed greater ampicillin, amikacin, cefazolin, cefazolin, and nalidixic acid resistance than the others. The bivariate results indicate several antibiotic pairings, and isolates had meaningful associations. All MDR isolates were subjected to PCR, which revealed that blaCTX-M-15 genes predominated among the isolates, followed by the blaTEM class (37%). Isolates also had the qnrS, aac-6´-Ib-cr, and gyrA genes. The findings provide worrying indications of a major expansion of MDR isolates in the study locations, particularly the epidemiological balCTX-M 15, with the potential for the transmission of multi-drug-resistant UP strains in the population.

Urinary Biomarkers and Point-of-Care Urinalysis Devices for Early Diagnosis and Management of Disease: A Review

Biosensing and microfluidics technologies are transforming diagnostic medicine by accurately detecting biomolecules in biological samples. Urine is a promising biological fluid for diagnostics due to its noninvasive collection and wide range of diagnostic biomarkers. Point-of-care urinalysis, which integrates biosensing and microfluidics, has the potential to bring affordable and rapid diagnostics into the home to continuing monitoring, but challenges still remain. As such, this review aims to provide an overview of biomarkers that are or could be used to diagnose and monitor diseases, including cancer, cardiovascular diseases, kidney diseases, and neurodegenerative disorders, such as Alzheimer’s disease. Additionally, the different materials and techniques for the fabrication of microfluidic structures along with the biosensing technologies often used to detect and quantify biological molecules and organisms are reviewed. Ultimately, this review discusses the current state of point-of-care urinalysis devices and highlights the potential of these technologies to improve patient outcomes. Traditional point-of-care urinalysis devices require the manual collection of urine, which may be unpleasant, cumbersome, or prone to errors. To overcome this issue, the toilet itself can be used as an alternative specimen collection and urinalysis device. This review then presents several smart toilet systems and incorporated sanitary devices for this purpose.

Developing a machine learning prediction algorithm for early differentiation of urosepsis from urinary tract infection

OBJECTIVES

Early recognition and timely intervention for urosepsis are key to reducing morbidity and mortality. Blood culture has low sensitivity, and a long turnaround time makes meeting the needs of clinical diagnosis difficult. This study aimed to use biomarkers to build a machine learning model for early prediction of urosepsis.

METHODS

Through retrospective analysis, we screened 157 patients with urosepsis and 417 patients with urinary tract infection. Laboratory data of the study participants were collected, including data on biomarkers, such as procalcitonin, D-dimer, and C-reactive protein. We split the data into training (80%) and validation datasets (20%) and determined the average model prediction accuracy through cross-validation.

RESULTS

In total, 26 variables were initially screened and 18 were statistically significant. The influence of the 18 variables was sorted using three ranking methods to further determine the best combination of variables. The Gini importance ranking method was found to be suitable for variable filtering. The accuracy rates of the six machine learning models in predicting urosepsis were all higher than 80%, and the performance of the artificial neural network (ANN) was the best among all. When the ANN included the eight biomarkers with the highest influence ranking, its model had the best prediction performance, with an accuracy rate of 92.9% and an area under the receiver operating characteristic curve of 0.946.

CONCLUSIONS

Urosepsis can be predicted using only the top eight biomarkers determined by the ranking method. This data-driven predictive model will enable clinicians to make quick and accurate diagnoses.

Nomogram for predicting risk factors of fever in patients with negative preoperative urine culture after retrograde intrarenal surgery

PURPOSE

To determine the risk factors for postoperative fever after retrograde intrarenal surgery (RIRS) in patients with negative preoperative urine culture (UC), and to establish a nomogram for predicting postoperative fever based on these risk factors.

METHODS

This study collected 322 patients with negative UC who received RIRS at the First Affiliated Hospital of Anhui Medical University from March 2019 to May 2022. The study population was divided into a fever group and a non-fever group. The risk factors of postoperative fever were determined by univariate and multivariate logistic regression analyses, and a nomogram was established. The nomogram was evaluated in terms of differentiation, calibration, and clinical practicability.

RESULTS

In this study, 47 (14.6%) patients developed a fever after surgery. Multivariate logistic regression analysis showed that for patients with negative preoperative urine culture, urinary leucocyte esterase (P = 0.005), operative time (P = 0.019), and intraoperative hypotension (P = 0.028) were independent risk factors of postoperative fever, and a nomogram was constructed according to the above variables. The area under the curve (AUC) calculated by receiver operating characteristic (ROC) analysis was 0.807 (95% CI 0.739-0.876), indicating good discrimination. The calibration curves showed good consistency, and the clinical decision curve analysis (DCA) showed the clinical applicability of the model.

CONCLUSIONS

For patients with negative preoperative urine culture, urine leukocyte esterase, operative time, and intraoperative hypotension are independent risk factors of postoperative fever. The new nomogram can better assess the risk of infection in patients with negative UC after RIRS.

Application of metagenomic next-generation sequencing in the diagnosis of urinary tract infection in patients undergoing cutaneous ureterostomy

Objective

Urinary tract infection (UTI) is an inflammatory response of the urothelium to bacterial invasion and is a common complication in patients with cutaneous ureterostomy (CU). For such patients, accurate and efficient identification of pathogens remains a challenge. The aim of this study included exploring utility of metagenomic next-generation sequencing (mNGS) in assisting microbiological diagnosis of UTI among patients undergoing CU, identifying promising cytokine or microorganism biomarkers, revealing microbiome diversity change and compare virulence factors (VFs) and antibiotic resistance genes (ARGs) after infection.

Methods

We performed a case-control study of 50 consecutive CU patients from December 2020 to January 2021. According to the clinical diagnostic criteria, samples were divided into infected group and uninfected group and difference of urine culture, cytokines, microorganism, ARGs and VFs were compared between the two groups.

Results

Inflammatory responses were more serious in infected group, as evidenced by a significant increase in IFN-α (p=0.031), IL-1β (0.023) and IL-6 (p=0.018). Clinical culture shows that there is higher positive rate in infected group for most clinical pathogens like Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Candida auris etc. and the top three pathogens with positive frequencies were E. coli, K. pneumoniae, and Enterococcus faecalis. Benchmarking clinical culture, the total sensitivity is 91.4% and specificity is 76.3% for mNGS. As for mNGS, there was no significant difference in microbiome α- diversity between infected and uninfected group. Three species biomarkers including Citrobacter freundii, Klebsiella oxytoca, and Enterobacter cloacae are enriched in infected group based on Lefse. E. cloacae were significantly correlated with IL-6 and IL-10. K. oxytoca were significantly correlated with IL-1β. Besides, the unweighted gene number and weighted gene abundance of VFs or ARGs are significantly higher in infected group. Notablely, ARGs belonging to fluoroquinolones, betalatmas, fosfomycin, phenicol, phenolic compound abundance is significantly higher in infected group which may have bad effect on clinical treatment for patients.

Conclusion

mNGS, along with urine culture, will provide comprehensive and efficient reference for the diagnosis of UTI in patients with CU and allow us to monitor microbial changes in urine of these patients. Moreover, cytokines (IL-6, IL-1β, and IFN-a) or microorganisms like C. freundii, K. oxytoca or E. cloacae are promising biomarkers for building effective UTI diagnostic model of patients with CU and seriously the VFs and ARGs abundance increase in infected group may play bad effect on clinical treatment.

Microbiome and Prostate Cancer: A Novel Target for Prevention and Treatment

Growing evidence of the microbiome's role in human health and disease has emerged since the creation of the Human Microbiome Project. Recent studies suggest that alterations in microbiota composition (dysbiosis) may play an essential role in the occurrence, development, and prognosis of prostate cancer (PCa), which remains the second most frequent male malignancy worldwide. Current advances in biological technologies, such as high-throughput sequencing, transcriptomics, and metabolomics, have enabled research on the gut, urinary, and intra-prostate microbiome signature and the correlation with local and systemic inflammation, host immunity response, and PCa progression. Several microbial species and their metabolites facilitate PCa insurgence through genotoxin-mediated mutagenesis or by driving tumor-promoting inflammation and dysfunctional immunosurveillance. However, the impact of the microbiome on PCa development, progression, and response to treatment is complex and needs to be fully understood. This review addresses the current knowledge on the host-microbe interaction and the risk of PCa, providing novel insights into the intraprostatic, gut, and urinary microbiome mechanisms leading to PCa carcinogenesis and treatment response. In this paper, we provide a detailed overview of diet changes, gut microbiome, and emerging therapeutic approaches related to the microbiome and PCa. Further investigation on the prostate-related microbiome and large-scale clinical trials testing the efficacy of microbiota modulation approaches may improve patient outcomes while fulfilling the literature gap of microbial-immune-cancer-cell mechanistic interactions.

Urinary Tract Infection Induced Delirium in Elderly Patients: A Systematic Review

Urinary tract infection (UTI) is common in older adults, mainly due to several age-related risk factors. Symptoms of UTI are atypical in the elderly population, like hypotension, tachycardia, urinary incontinence, poor appetite, drowsiness, frequent falls, and delirium. UTI manifests more commonly and specifically for this age group as delirium or confusion in the absence of a fever. This systematic review aims to highlight the relationship between UTI and delirium in the elderly population by understanding the pathologies individually and collectively. A systematic review is conducted by searching PubMed with regular keywords and major Medical Subject Heading (MeSH) keywords, Science Direct, and Google Scholar. The inclusion criteria consisted of studies based on male and female human populations above the age of 65 in the English language, available in full text published between 2017 and 2022. However, the exclusion criteria were animal studies, clinical trials, literature published before 2017, and papers published in any other language except English. A total of 106 articles were identified, and nine final studies were selected after a quality assessment, following which a valid relationship between delirium and UTI was identified in this systematic review.

Ureaplasma urealyticum induces polymorphonuclear elastase to change semen properties and reduce sperm motility: a prospective observational study

Objective

To elucidate the mechanism underlying how Ureaplasma urealyticum (UU) affects sperm quality and identify a therapeutic target.

Methods

In this prospective observational study, the differences in and relationships among semen volume, pH, viscosity, liquefaction time, sperm concentration, sperm motility [progressive motility (PR)], and seminal polymorphonuclear (PMN) elastase were analyzed in 198 normal semen samples (control group) and 198 UU-infected semen samples (observation group). The UU-infected samples were treated and the above parameters were compared between the two groups.

Results

The semen volume, viscosity, liquefaction time, and seminal PMN elastase were significantly higher in the observation than control group, but the pH and PR were significantly lower. In the observation group, the pH and PR were significantly higher after than before treatment, whereas the semen volume, PMN elastase, viscosity, and liquefaction time were lower. UU was closely related to semen volume, pH, viscosity, liquefaction time, sperm motility (PR), and PMN elastase. PMN elastase had significant negative effects on semen pH and sperm motility (PR) but positive effects on viscosity and liquefaction time.

Conclusion

UU might induce PMN elastase to increase the liquefaction time and viscosity of semen, eventually decreasing PR. PMN elastase might be a therapeutic target of UU.

Pathogen profile of urinary tract infections in Nephrology Unit

Introduction. Urinary tract infection (UTI) is one of the most common types of infection in both hospitalized and outpatient settings. The etiology is mostly bacterial, and the typical causative agent is uropathogenic Escherichia coli. There is a noticeable increase in drug resistance of pathogenic microorganisms.

The aim of the study was retrospective analyses of etiological agents of UTI and their antibiotic resistance patterns in Nephrology Unit patients.

Material and methods. An infection was diagnosed based on the patient’s symptoms and positive results of urine culture, carried out over 26 months. The clinical material was tested by using the VITEK system, the drug susceptibility of the emerged pathogens was identified.

Results. The most common etiological agents of UTI were Gram-negative rods: Escherichia coli (51.23%), Klebsiella spp. (19.3%) and Proteus spp. (13.68%). The analysis of drug resistance profiles of these pathogens showed a high percentage of strains resistant to broad-spectrum penicillins and fluoroquinolones. At the same time, it seems that E. coli isolates presented the most favorable pattern of drug susceptibility in this comparison.

Conclusions. The alarming tendency of increasing drug resistance among pathogens causing UTIs to antibiotics such as penicillins or fluoroquinolones prompts a careful choice of drugs in empirical therapies. The most appropriate practice in this regard seems to be meticulous control of nosocomial infections and making therapeutic decisions based on the knowledge of local microbiological data.

Urinary tract infection in patients with chronic kidney disease under conservative treatment

OBJECTIVES

to assess the prevalence and associated risk factors for urinary tract infection in patients with chronic kidney disease under conservative treatment and identify the microorganisms isolated in the urine of these patients and the staging of chronic kidney disease.

METHODS

a cross-sectional, analytical study carried out at the Conservative Treatment Outpatient Clinic of a university hospital in the city of São Paulo.

RESULTS

the prevalence of urinary tract infection is 22%. The risk factors Diabetes Mellitus, hypertension, heart disease, neoplasms and thyroid and autoimmune diseases stand out in the infected group (p < 0.001). Most of the microorganisms found in urine cultures (87.9%) were Gram-negative, being Escherichia coli (50.70%), followed by Klebsiella pneumoniae (23.1%) and Enterococcus spp. (9.7%).

CONCLUSIONS

the findings of this investigation reveal the intrinsic association between risk factors and microorganisms for the development of urinary tract infection.

Revisiting approaches to and considerations for urinalysis and urine culture reflexive testing

Urinalysis is considered the world's oldest laboratory test. Today, many laboratories use macroscopic urinalysis as a screening tool to determine when to subject urine samples for a microscopic urinalysis and/or bacterial culture. While reflexive urine microscopy has been practiced for decades, and reflexive urine culture, more recently, evidence-based guidelines regarding optimal reflexive criteria and workflows are lacking. Standard approaches are hindered, in part, by a lack of harmonization of urinalysis and urine culture practices, heterogeneity in patient populations that are studied, and lack of provider adherence to recommended practices. This review summarizes studies that have evaluated the performance of reflexive urine microscopy and reflexive urine culture, particularly in the context of urinary tract infections. It also examines reported clinical outcomes from reflexive urinalysis interventions and their impact on antibiotic stewardship efforts. Finally, it discusses laboratory operational considerations for the implementation of reflexive algorithms.

Improved diagnostics of infectious diseases in emergency departments: a protocol of a multifaceted multicentre diagnostic study

BACKGROUND

The major obstacle in prescribing an appropriate and targeted antibiotic treatment is insufficient knowledge concerning whether the patient has a bacterial infection, where the focus of infection is and which bacteria are the agents of the infection. A prerequisite for the appropriate use of antibiotics is timely access to accurate diagnostics such as point-of-care (POC) testing.The study aims to evaluate diagnostic tools and working methods that support a prompt and accurate diagnosis of hospitalised patients suspected of an acute infection. We will focus on the most common acute infections: community-acquired pneumonia (CAP) and acute pyelonephritis (APN). The objectives are to investigate (1) patient characteristics and treatment trajectory of the different acute infections, (2) diagnostic and prognostic accuracy of infection markers, (3) diagnostic accuracy of POC urine flow cytometry on diagnosing and excluding bacteriuria, (4) how effective the addition of POC analysis of sputum to the diagnostic set-up for CAP is on antibiotic prescriptions, (5) diagnostic accuracy of POC ultrasound and ultralow dose (ULD) computerized tomography (CT) on diagnosing CAP, (6) diagnostic accuracy of specialist ultrasound on diagnosing APN, (7) diagnostic accuracy of POC ultrasound in diagnosing hydronephrosis in patients suspected of APN.

METHODS AND ANALYSIS

It is a multifaceted multicentre diagnostic study, including 1000 adults admitted with suspicion of an acute infection. Participants will, within the first 24 hours of admission, undergo additional diagnostic tests including infection markers, POC urine flow cytometry, POC analysis of sputum, POC and specialist ultrasound, and ULDCT. The primary reference standard is an assigned diagnosis determined by a panel of experts.

ETHICS, DISSEMINATION AND REGISTRATION

Approved by Regional Committees on Health Research Ethics for Southern Denmark, Danish Data Protection Agency and clinicaltrials.gov. Results will be presented in peer-reviewed journals, and positive, negative and inconclusive results will be published.

TRIAL REGISTRATION NUMBERS

NCT04661085, NCT04681963, NCT04667195, NCT04652167, NCT04686318, NCT04686292, NCT04651712, NCT04645030, NCT04651244.

A Proteomics Approach to Identify Possible Biomarkers of Early and Late Stages of E. coli-induced Urinary Tract Infections

As one of the most common bacterial infections globally, urinary tract infections (UTI)s affect the bladder and kidneys of many the bladders and kidneys of many. Along with gram-negative bacteria, Escherichia coli (E. coli) causes nearly 40% of nosocomial UTIs, 25% of recurrent infections, and between 80 to 90% of community-acquired infections. Proteomics, commonly used to study changes in protein expression of organisms, can be used to explore candidate biomarkers useful for the diagnosis of pathological conditions. Here, protein profiles of samples from patients diagnosed with E. coli-induced UTI were compared to identify distinctive proteins. Extracted proteins from bacteria from patients’ urine samples were separated into excisable spots using 2D-gel electrophoresis. The gels were then analyzed using Progenesis SameSpot software to select uniquely expressed protein spots, excised, and analyzed by LC/MS. The results were then compared against a database of known proteins. We identified two proteins, outer membrane protein A (OmpA) and RNA polymerase-binding transcription factor (DksA), involved in the survival of E. coli in the harsh environment of the host. We suggest their use as a part of a battery of possible biomarkers proteins for E. coli-induced UTI, and suggest that their overexpression is possibly associated with the stage of infection, early or late.

Factors for return to emergency department and hospitalization in elderly urinary tract infection patients

BACKGROUND

Appropriate decision of emergency department (ED) disposition is essential for improving the outcome of elderly urinary tract infection (UTI) patients. However, studies on early return visit (ERV) to the ED in elderly UTI patients are limited. Therefore, we aimed to identify factors for ERV and hospitalization after return visit (HRV) in this population.

METHODS

Elderly patients discharged from the ED with International Classification of diseases 10th Revision codes of UTI were selected from the registry for evaluation of ED revisit in 6 urban teaching hospitals. Retrospective data were extracted from the electronic medical records and ERV and hospitalization to scheduled revisit (SRV) were compared.

RESULT

Among a total of 419 patients found in the study period, 45 were ERV patients and 24 were HRV patients. Absence of UTI-specific symptoms (odds ratio [OR] 2.789; 95% confidence interval [CI] 1.368-5.687; P = 0.005), C-reactive protein (CRP) levels >30 mg/L (OR 2.436; 95% CI 1.017-3.9; P = 0.024), and body temperature ≥ 38 °C (OR 1.992; 95% CI 1.017-3.9; P = 0.044) were independent risk factors for ERV, and absence of UTI-specific symptoms (OR 3.832; 95% CI 1.455-10.088; P = 0.007), CRP levels >30 mg/L (OR 3.224; 95% CI 1.235-8.419; P = 0.017), and systolic blood pressure ≤ 100 mmHg (OR 3.795;95% CI 1.156-12.462; P = 0.028) were independent risk factors for HRV. However, there was no significant difference in empirical antibiotic resistance in ERV and HRV patients, compared to SRV patients.

CONCLUSION

The independent risk factors of ERV and HRV should be considered for ED disposition in elderly UTI patients; the resistance to empirical antibiotics was not found to affect ERV or HRV within 3 days.

Plasma D-Dimer as a Marker of Urinary Tract Infection in Children

Background: Urinary tract infections (UTIs) are very common in children. Several biomarkers have been used for the diagnosis of UTI and prediction of renal parenchymal involvement. Objectives: This study aimed to evaluate plasma D-dimer as a diagnostic marker of UTI in children. Methods: This cross-sectional study included 41 children aged 1 month to 14 years with their first febrile UTI confirmed by positive urine culture referred to Bandar Abbas Children’s Hospital, Iran, from October 1, 2017, to April 1, 2018. Participants’ demographic features, including age and gender were recorded. White blood cell (WBC) count, percentage of neutrophils, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum D-dimer were measured in random blood samples for all the patients. Results: Out of 41 children (mean age: 5.50 ± 4.01 years) evaluated in this study, 6 (14.6%) were male, and 35 (85.4%) were female. The mean plasma D-dimer level was 1496.49 ± 2787.55 µg/L. A significant positive correlation was found between D-dimer with ESR (r = 0.647, P = 0.026) and CRP (r = 0.525, P = 0.001). Plasma D-dimer was not associated with age; however, age was inversely correlated with WBC count (r = -0.327, P = 0.037). No significant relationship was found between plasma D-dimer, ESR, CRP, WBC count, and neutrophil percentage with gender (P > 0.05). Conclusions: According to our results, in children aged 1 month to 14 years with culture-confirmed UTI, plasma D-dimer is positively correlated with ESR and CRP. Nevertheless, D-dimer appears not to be influenced by age or gender. Further studies are required to confirm the utility of D-dimer as a diagnostic marker of UTI in children.

Driving to Safety: CRISPR-Based Genetic Approaches to Reducing Antibiotic Resistance

Bacterial resistance to antibiotics has reached critical levels, skyrocketing in hospitals and the environment and posing a major threat to global public health. The complex and challenging problem of reducing antibiotic resistance (AR) requires a network of both societal and science-based solutions to preserve the most lifesaving pharmaceutical intervention known to medicine. In addition to developing new classes of antibiotics, it is essential to safeguard the clinical efficacy of existing drugs. In this review, we examine the potential application of novel CRISPR-based genetic approaches to reducing AR in both environmental and clinical settings and prolonging the utility of vital antibiotics.

The impact of obesity on immune response to infection: Plausible mechanisms and outcomes

Emerging data suggest an association between obesity and infectious diseases. Although the mechanisms underlying this link are not well established, a number of potential factors may be involved. Indeed, the obesity-related vulnerability to infectious diseases could be due to chronic low-grade inflammation, hyperglycemia, hyperinsulinemia, and hyperleptinemia, which lead to a weakening of both the innate and adaptive immune responses. In addition, obesity results in anatomical-functional changes by the mechanical obstacle of excessive adipose tissue that blunt the respiratory mechanisms and predisposing to respiratory infections. Subjects with obesity are also at risk of skin folds and sweat more profusely due to the thick layers of subcutaneous fat, favoring the proliferation of microorganisms and slowing the repair of wounds down. All these factors make subjects with obesity more prone to develop nosocomial infections, surgical site, skin and soft tissue infections, bacteremia, urinary tract infections, and mycosis. Furthermore, infections in subjects with obesity have a worse prognosis, frequently prolonging hospitalization time as demonstrated for several flu viruses and recently for COVID-19. Thus, the aim of this manuscript is to provide an overview of the current clinical evidence on the associations between obesity and infectious diseases highlighting physio pathological insights involved in this link.

What Is the Optimal Timing for Reading the Leukocyte Esterase Strip for the Diagnosis of Periprosthetic Joint Infection?

BACKGROUND

The leucocyte esterase (LE) strip test often is used to diagnose periprosthetic joint infection (PJI). In accordance with the manufacturer's directions, the LE strip test result is read 3 minutes after exposing it to joint fluid, but this has not been supported by robust research. Moreover, we have noted that the results of the LE strip test might change over time, and our previous studies have found that centrifugation causes the results of the LE strip test to degrade. Still, there is no evidence-based recommendation as to when to read the LE strip test to maximize diagnostic accuracy, in general, and the best reading times for the LE strip test before and after centrifugation need to be determined separately, in particular.

QUESTIONS/PURPOSES

(1) What is the optimal timing for reading LE strip test results before centrifugation to diagnose PJI? (2) What is the optimal timing for reading LE strip test results after centrifugation to diagnose PJI?

METHODS

This study was a prospective diagnostic trial. In all, 120 patients who were scheduled for revision arthroplasty and had signs of infection underwent joint aspiration in the outpatient operating room between July 2018 and July 2019 and were enrolled in this single-center study. For inclusion, patients must have had a diagnosis of PJI or nonPJI, valid synovial fluid samples, and must not have received antibiotics within 2 weeks before arthrocentesis. As such, 36 patients were excluded; 84 patients were included for analysis, and all 84 patients agreed to participate. The 2018 International Consensus Meeting Criteria (ICM 2018) was used for the classification of 49 patients with PJI (score ≥ 6) and 35 without PJI (score ≤ 2). The classification was used as the standard against which the different timings for reading LE strips were compared. All patients without PJI were followed for more than 1 year, during which they did not report the occurrence of PJI. All patients were graded against the diagnostic criteria regardless of their LE strip test results. In 83 patients, one drop of synovial fluid (50 μL) was applied to LE strips before and after centrifugation, and in one patient (without PJI), the sample was not centrifuged because the sample volume was less than 1.5 mL. The results of the strip test were read on an automated colorimeter. Starting from 1 minute after centrifugation, these strips were automatically read once every minute, 15 times (over a period of 16 minutes), and the results were independently recorded by two observers. Results were rated as negative, ±, 1+, and 2+ upon the machine reading. Grade 2+ (dark purple) was used as the threshold for a positive result. An investigator who was blinded to the study performed the statistics. Optimal timing for reading the LE strip before and after centrifugation was determined by using receiver operative characteristic (ROC) analysis. The specificity, sensitivity, and positive predictive and negative predictive values were calculated for key timepoints.

RESULTS

Before centrifugation, the area under the curve was the highest when the results were read at 5 minutes (0.90 [95% CI 0.83 to 0.98]; sensitivity 0.88 [95% CI 0.75 to 0.95]; specificity 0.89 [95% CI 0.72 to 0.96]). After centrifugation, the area under the curve was the highest when the results were read at 10 minutes (0.92 [95% CI 0.86 to 0.98]; sensitivity 0.65 [95% CI 0.50 to 0.78]; specificity 0.97 [95% CI 0.83 to 1.00]).

CONCLUSION

The LE strip test results are affected by time and centrifugation. For samples without centrifugation, we found that 5 minutes after application was the best time to read LE strips. We cannot deny the use of centrifuges because this is an effective way to solve the sample-mingling problem at present. We recommend 10 minutes postapplication as the most appropriate time to read LE strips after centrifugation. Multicenter and large-sample size studies are warranted to further verify our conclusion.

LEVEL OF EVIDENCE

Level II, diagnostic study.

Frailty associated urinary tract infections (FaUTIs)

This review summarizes the current literature on the correlation between frailty and urinary tract infections (UTIs), as well as the potential causes and measures that can be taken to prevent and treat these frailty associated UTIs (FaUTIs). A narrative review of the literature was carried out using the keywords and other associated terms (catheter associated UTIs and frailty, causes of UTIs, prevention of UTIs in the frail, treatment of UTIs in the frail). As it is shown in the literature, many risk factors that are associated with frailty such as dehydration, reduced mobility and cognitive impairment, as well as other anatomical or functional abnormalities can make frail patients prone to UTIs that are also more difficult to treat. Early correction of these risk factors (for example avoiding long term catheters, increasing hydration, treating lower urinary tract obstruction or incontinence), can prevent UTIs and improve the quality of life of frail patients. Prompt and individualized antimicrobial treatment of UTIs in the frail population can result in decreasing mortality rates but also minimize unnecessary antimicrobial drug use.

Manual treatment for kidney mobility and symptoms in women with nonspecific low back pain and urinary infections

CONTEXT

Recent studies have suggested a connection between low back pain (LBP) and urinary tract infections (UTI). These disturbances could be triggered via visceral-somatic pathways, and there is evidence that kidney mobility is reduced in patients suffering from nonspecific LBP. Manual treatment of the perinephric fascia could improve both kidney mobility and LBP related symptoms.

OBJECTIVES

To assess whether manual treatment relieves UTI and reduces pain in patients with nonspecific LBP through improvement in kidney mobility.

METHODS

Records from all patients treated at a single physical therapy center in 2019 were retrospectively reviewed. Patients were included if they were 18 years of age or older, had nonspecific LBP, and experienced at least one UTI episode in the 3 months before presentation. Patients were excluded if they had undergone manipulative treatment in the 6 months before presentation, if they had one of several medical conditions, if they had a history of chronic pain medication use, and more. Patient records were divided into two groups for analysis: those who were treated with manipulative techniques of the fascia with thrust movement (Group A) vs those who were treated without thrust movement (Group B). Kidney Mobility Scores (KMS) were analyzed using high resolution ultrasound. Symptoms as reported at patients' 1 month follow up visits were also used to assess outcomes; these included UTI relapse, lumbar spine mobility assessed with a modified Schober test, and lumbar spine pain.

RESULTS

Of 126 available records, 20 patients were included in this retrospective study (10 in Group A and 10 in Group B), all of whom who completed treatment and attended their 1 month follow up visit. Treatments took place in a single session for all patients and all underwent ultrasound of the right kidney before and after treatment. The mean (± standard deviation) KMS (1.9 ± 1.1), mobility when bending (22.7 ± 1.2), and LBP scores (1.2 ± 2.6) of the patients in Group A improved significantly in comparison with the patients in Group B (mean KMS, 1.1 ± 0.8; mobility when bending, 21.9 ± 1.1; and LBP, 3.9 ± 2.7) KMS, p<0.001; mobility when bending, p=0.003; and LBP, p=0.007). At the 1 month follow up visit, no significant statistical changes were observed in UTI recurrence (secondary outcome) in Group A (-16.5 ± 4.3) compared with Group B (-20.4 ± 7) (p=0.152).

CONCLUSIONS

Manual treatments for nonspecific LBP associated with UTI resulted in improved mobility and symptoms for patients in this retrospective study, including a significant increase in kidney mobility.

Nanomaterials for the Diagnosis and Treatment of Urinary Tract Infections

The diagnosis and treatment of urinary tract infections (UTIs) remain challenging due to the lack of convenient assessment techniques and to the resistance to conventional antimicrobial therapy, showing the need for novel approaches to address such problems. In this regard, nanotechnology has a strong potential for both the diagnosis and therapy of UTIs via controlled delivery of antimicrobials upon stable, effective and sustained drug release. On one side, nanoscience allowed the production of various nanomaterial-based evaluation tools as precise, effective, and rapid procedures for the identification of UTIs. On the other side, nanotechnology brought tremendous breakthroughs for the treatment of UTIs based on the use of metallic nanoparticles (NPs) for instance, owing to the antimicrobial properties of metals, or of surface-tailored nanocarriers, allowing to overcome multidrug-resistance and prevent biofilm formation via targeted drug delivery to desired sites of action and preventing the development of cytotoxic processes in healthy cells. The goal of the current study is therefore to present the newest developments for the diagnosis and treatment of UTIs based on nanotechnology procedures in relation to the currently available techniques.

Microbiological profile of urinary tract infections in a tertiary medical facility in Western Mexico: An update

Urinary tract infections (UTIs) are one of the most important issues in modern medicine. In developing countries, the use of antibiotics is a common practice, and due to this, antibiotic resistance has increased. The objective of this research was to update and report on the microbiological profile of urinary tract infections based on the number of positive urine cultures (UCs), resistance, sensitivity, and the prevalence of bacterial strains. The results were obtained from the database of a tertiary medical facility in Western Mexico. The number of positive UCs was 1769 from inpatients and outpatients who were users of medical services in the hospital from January to December of 2017. The most commonly isolated microorganism was E. coli, with 1225 cases, of which 603 (49.2%) were ESBL (Extended-Spectrum Beta-Lactamase-producing bacteria) strains. The resistance rate of nitrofurantoin was 36.6%, and meropenem showed the most promising results with a resistance rate of only 7.1%. Resistances to quinolones and cephalosporins among the isolates investigated were 51%-67%. Based on our results, it is necessary to increase controls and to improve management protocols in order to achieve better medical practices by reducing antibiotic resistance.

Procalcitonin as an early indicator of urosepsis following prostate biopsy

BACKGROUND

To investigate the usefulness of serum procalcitonin (PCT) in the early diagnosis of urinary tract infection (UTI) and urosepsis following transrectal prostate biopsy.

METHODS

In this prospective observational study, 227 patients who underwent transrectal ultrasound-guided prostate biopsy were evaluated. The relationship between urosepsis and age, serum PCT, C-reactive protein, prostate-specific antigen (PSA), prostate volume, PSA density and pathologic results following biopsy was assessed. Serum PCT level was measured in all patients immediately before the biopsy and at the post-biopsy day 2.

RESULTS

Of the 227 patients, 11 (4.8%) developed UTI with positive urine culture without urosepsis and 5 (2.2%) developed urosepsis within 30 days after biopsy. The concentration of PCT was within the normal range before the biopsy. Procalcitonin concentration at post-biopsy day 2 was significantly higher in patients who developed urosepsis (1.91 ± 2.99 ng/ml vs. 0.05 ± 0.08 ng/ml; p = .004) compared with non-UTI patients. Only elevated PCT level at post-biopsy day 2 was a statistically significant independent predictor of post-biopsy urosepsis. The area under the ROC curve for the prediction of urosepsis was 0.976 (95%CI: 0.941-1.000) and a cut-off 0.095 ng/ml in the level of PCT at post-biopsy day 2 yielded a sensitivity of 100% and specificity of 93.8% in detecting urosepsis following biopsy.

CONCLUSIONS

Procalcitonin appears to be a useful early biomarker to predict the urosepsis following prostate biopsy. Patients with elevated PCT value should be closely monitored after the biopsy.

The Use of Serum Procalcitonin in the Setting of Infected Ureteral Stones: A Prospective Observational Study

Introduction: Infected ureteral stones are a urologic emergency and require urgent decompression. We set out to determine whether serum procalcitonin (PCT) could aid in the diagnosis of infected ureteral stones. Methods: All consecutive patients presenting to the emergency room from November 9, 2016, to November 10, 2018, with an obstructing ureteral stone were included. All patients had complete blood count, urinalysis (UA), PCT, and urine culture (UCx). Subgroup analysis was performed in a "clinically equivocal" cohort of afebrile patients defined as a leukocytosis >10⁴/μL and UA with <50 white blood cells (WBCs) per high powered field (hpf). Patients with positive and negative UCx were compared. Results: A total of 231 patients were included, of whom 56 had a positive UCx. Of all covariates, UA WBCs with a cutoff of 9 per hpf performed best at predicting positive UCx with an area under the curve (AUC) of 0.87. PCT did not perform as well with an ideal cutoff of 0.08 ng/mL, having an AUC of 0.77, sensitivity 70.6%, specificity 73.9%, positive predictive value (PPV) 34.3%, and negative predictive value (NPV) 92.9%. When looking at the clinically equivocal cohort, UA WBCs with a cutoff of 6 per hpf appeared to perform best at predicting a positive UCx with an AUC of 0.72. PCT was less predictive in this cohort with an ideal cutoff of 0.3 ng/mL, having an AUC of 0.32, sensitivity 47.1%, specificity 85.2%, PPV 38.1%, and NPV 89.3%. Conclusion: PCT does not appear to be a superior marker for diagnosing urinary tract infection in the setting of obstructing ureterolithiasis when compared with components of the standard work-up.

Application of leukocyte esterase strip test in the screening of periprosthetic joint infections and prospects of high-precision strips

Periprosthetic joint infection (PJI) represents one of the most challenging complications after total joint arthroplasty (TJA). Despite the availability of a variety of diagnostic techniques, the diagnosis of PJI remains a challenge due to the lack of well-established diagnostic criteria. The leucocyte esterase (LE) strips test has been proved to be a valuable diagnostic tool for PJI, and its weight in PJI diagnostic criteria has gradually increased. Characterized by its convenience, speed and immediacy, leucocyte esterase strips test has a prospect of broad application in PJI diagnosis. Admittedly, the leucocyte esterase strips test has some limitations, such as imprecision and liability to interference. Thanks to the application of new technologies, such as machine reading, quantitative detection and artificial intelligence, the LE strips test is expected to overcome the limitations and improve its accuracy.

Quantitative determination of leukocyte esterase with a paper-based device

The commercially-available colorimetric urine dipstic for the early detection of urinary tract infection (UTI) has several limitations. The quantitative determination of urinary leukocyte esterase (LE) for predicting UTI remains uncertain. This study presents a paper-based analytical device to detect LE (LE-PAD) as a point-of-care quantitative test for UTI. The LE-PAD is composed of a coating of mixed 3-(N-tosyl-L-alaninyloxy)-5-phenylpyrrole (PE) and 1-diazo-2-naphthol-4-sulfonic acid (DAS) deposited onto a silver conducting film (Ag film). The LE/urine reacts with the PE and DAS, and the resulting products in turn react with the silver coating, causing a change in resistivity. The quantitative calibration curve was established in this study and has been used to analyse urine samples from inpatients with urinary catheters (n = 21). The results revealed that the level of LE determined by LE-PADs was predictive of UTI diagnosis with an area under the receiver operating characteristic curve of 0.875 (95% confidence interval, 0.704-1.000). Using an appropriate cut-off value, the sensitivity and specificity of UTI diagnosis by LE-PAD were 87.5% and 92.3%, while the LE-positivities of urine dipstics were 62.5% and 76.9%, respectively. For UTI diagnosis, the LE-PAD demonstrated positive and negative likelihood ratios of 11.38 and 0.14, suggesting that the novel LE-PAD is a reliable test.

Current controversies in urinary tract infections: ICI-RS 2017

AIMS

The current definition of urinary tract infection (UTI) relies on laboratory and clinical findings, which may or may not be relevant, depending upon the patient group under consideration. This report considers the utility of current definitions for UTI in adults with and without underlying neurological conditions in order to identify gaps in current understanding and to recommend directions for research.

METHODS

This is a consensus report of the proceedings of Think Tank TT3: "How do we define and when do we treat UTI in neurological and non-neurological adult patients?" from the annual International Consultation on Incontinence-Research Society (ICI-RS), June 8-10, 2017 (Bristol, UK).

RESULTS

Evidence considering the definitions of UTI in patients with and without neurological diseases was reviewed and synthesized. We examined research on laboratory methods and clinical definitions, focusing on specific cut-off values for the quantification of significant bacteriuria, and leucocyturia. Several areas were identified, mostly related to the lack of evidence-based definitions of significant bacteriuria for different patient groups, as well as uncertainties about the role of inflammatory biomarkers, and non-specific symptoms and signs.

CONCLUSIONS

One of the biggest challenges in clinical practice is to discriminate between asymptomatic bacteriuria and symptomatic UTI. Future research should concentrate on risk factors for developing symptomatic UTI in different patient groups. Targeted investigations for specific populations, such as the frail elderly, and patients with neurogenic bladder dysfunction, are still needed.

Which near-patient tests might improve the diagnosis of UTI in older people in urgent care settings? A mapping review and consensus process

PURPOSE

The aim of this study was to map out the existing knowledge on near-patient tests for urinary tract infections, and use a consensus building approach to identify those which might be worthy of further evaluation in the urgent care context, defined as clinically useful and feasible results available within 4-24 h.

METHODS

A systematic search for reviews describing diagnostic tests for UTI was undertaken in Medline, EMBASE, Cochrane database of systematic reviews and CINAHL selected reviews were retained according to a priori inclusion and exclusion criteria, and then graded for quality using the CASP tool for reviews. A consensus process involving microbiologists and chemical pathologists helped identify which test might conceivably be applied in the urgent care context (e.g. Emergency Department, giving results within 24 h).

RESULTS

The initial search identified 1079 papers, from which 26 papers describing 35 diagnostic tests were retained for review. The overall quality was limited, with only 7/26 retained papers scoring more than 50% on the CASP criteria. Reviews on urine dipstick testing reported wide confidence intervals for sensitivity and specificity; several raised concerns about urine dip testing in older people. A number of novel biomarkers were reported upon but appeared not to be helpful in differentiating infection from asymptomatic bacteriuria. Blood markers such as CRP and procalcitonin were reported to be helpful in monitoring rather than diagnosing UTI. The consensus process helped to refine the 35 test down to 17 that might be useful in the urgent care context: urinalysis (nitrites and leucocytes), uriscreen catalase test, lactoferrin, secretory immunoglobulin A, xanthine oxidase, soluble triggering receptor expressed on myeloid cells, A-1 microglobulin (a1 Mg) and a1 Mg/creatinine ratio, cytokine IL-6, RapidBac, MALDI-TOF, electronic noses, colorimetric sensor arrays, electro chemical biosensor, WBC count (blood), C-reactive peptide, erythrocyte sedimentation rate.

CONCLUSIONS

A wide range of diagnostic tests have been explored to diagnose UTI, but, in general, have been poorly evaluated or have wide variation in predictive properties. This study identified 17 tests for UTI that seemed to offer some primes and merit further evaluation for diagnosing UTI in older people in urgent care settings.

Augmentation of Urinary Lactoferrin Enhances Host Innate Immune Clearance of Uropathogenic Escherichia coli

Urinary tract infection (UTI) is a prominent global health care burden. Although UTI is readily treated with antibiotics in healthy adults, complicated cases in immune-compromised individuals and the emerging antibiotic resistance of several uropathogens have accelerated the need for new treatment strategies. Here, we surveyed the composition of urinary exosomes in a mouse model of uropathgenic Escherichia coli (UPEC) UTI to identify specific urinary tract defense constituents for therapeutic development. We found an enrichment of the iron-binding glycoprotein lactoferrin in the urinary exosomes of infected mice. In subsequent in vitro studies, we identified human bladder epithelial cells as a source of lactoferrin during UPEC infection. We further established that exogenous treatment with human lactoferrin (hLf) reduces UPEC epithelial adherence and enhances neutrophil antimicrobial functions including bacterial killing and extracellular trap production. Notably, a single intravesicular dose of hLf drastically reduced bladder bacterial burden and neutrophil infiltration in our murine UTI model. We propose that lactoferrin is an important modulator of innate immune responses in the urinary tract and has potential application in novel therapeutic design for UTI.

Synergy between nanomaterials and volatile organic compounds for non-invasive medical evaluation

This article is an overview of the present and ongoing developments in the field of nanomaterial-based sensors for enabling fast, relatively inexpensive and minimally (or non-) invasive diagnostics of health conditions with follow-up by detecting volatile organic compounds (VOCs) excreted from one or combination of human body fluids and tissues (e.g., blood, urine, breath, skin). Part of the review provides a didactic examination of the concepts and approaches related to emerging sensing materials and transduction techniques linked with the VOC-based non-invasive medical evaluations. We also present and discuss diverse characteristics of these innovative sensors, such as their mode of operation, sensitivity, selectivity and response time, as well as the major approaches proposed for enhancing their ability as hybrid sensors to afford multidimensional sensing and information-based sensing. The other parts of the review give an updated compilation of the past and currently available VOC-based sensors for disease diagnostics. This compilation summarizes all VOCs identified in relation to sickness and sampling origin that links these data with advanced nanomaterial-based sensing technologies. Both strength and pitfalls are discussed and criticized, particularly from the perspective of the information and communication era. Further ideas regarding improvement of sensors, sensor arrays, sensing devices and the proposed workflow are also included.

Urinary Tract Infection Antibiotic Resistance in the United States

Urinary tract infection (UTI) is one of the most common entities in medicine and affected patients present daily in a typical family medicine practice. The patients often present with the "classic symptoms" of dysuria and increased frequency, but sometimes they are asymptomatic or have a mixed picture. In most cases, an antibiotic is prescribed, and this practice is likely contributing to increasing worldwide antibiotic resistance. To help combat this problem, it is important that clinicians seek out their local bacterial resistance patterns and antibiograms, properly diagnose and treat UTI if indicated, and recognize their role in antibiotic stewardship.

A case-control study of lower urinary-tract infections, associated antibiotics and the risk of developing prostate cancer using PCBaSe 3.0

Objectives

To investigate the association between lower urinary-tract infections, their associated antibiotics and the subsequent risk of developing PCa.

Subjects/Patients (or materials) and methods

Using data from the Swedish PCBaSe 3.0, we performed a matched case-control study (8762 cases and 43806 controls). Conditional logistic regression analysis was used to assess the association between lower urinary-tract infections, related antibiotics and PCa, whilst adjusting for civil status, education, Charlson Comorbidity Index and time between lower urinary-tract infection and PCa diagnosis.

Results

It was found that lower urinary-tract infections did not affect PCa risk, however, having a lower urinary-tract infection or a first antibiotic prescription 6–12 months before PCa were both associated with an increased risk of PCa (OR: 1.50, 95% CI: 1.23–1.82 and 1.96, 1.71–2.25, respectively), as compared to men without lower urinary-tract infections. Compared to men with no prescriptions for antibiotics, men who were prescribed ≥10 antibiotics, were 15% less likely to develop PCa (OR: 0.85, 95% CI: 0.78–0.91).

Conclusion

PCa was not found to be associated with diagnosis of a urinary-tract infection or frequency, but was positively associated with short time since diagnoses of lower urinary-tract infection or receiving prescriptions for antibiotics. These observations can likely be explained by detection bias, which highlights the importance of data on the diagnostic work-up when studying potential risk factors for PCa.

Utility of initial procalcitonin values to predict urinary tract infection

BACKGROUND

Urinary tract infections (UTIs) are one of the most common reasons women seek treatment in the emergency department (ED). The biomarker procalcitonin (PCT) has gained popularity over the last decade to improve the diagnosis of bacterial infections and reduce unnecessary exposure to antibiotics. PCT has been extensively studied in patients with pneumonia and sepsis and may have additional role in UTI.

METHODS

A retrospective study of patients who presented to the ED in which a urinalysis test and a PCT level was obtained within the first 24h of presentation. Signs and symptoms of UTI and urine cultures were reviewed to determine a positive diagnosis of UTI. The area under the receiver operating curve was used to calculate the test characteristics of PCT. Different breakpoints were analyzed to determine which PCT level corresponded to the highest sensitivity and specificity.

RESULTS

293 patients were included in this single center, retrospective study. The AUC of PCT to predict UTI was 0.717; 95% CI: 0.643-0.791 (p<0.001). A PCT threshold of 0.25ng/ml corresponded to the best combination of sensitivity (67%) and specificity (63%), with a positive predictive value and negative predictive value of 26% and 91%, respectively.

CONCLUSIONS

A PCT threshold <0.25ng/ml was a strong predictor of the absence of UTI. The high negative predictive value of PCT may be useful as an adjunct to urinalysis results to rule out UTI and facilitate noninitiation or earlier discontinuation of empiric antibiotics.