Bacterial urinary tract infections (UTI) are a major growing concern worldwide. Uropathogenic Escherichia coli has been shown to invade the urothelium during acute UTI in mice and humans, forming intracellular reservoirs that can evade antibiotics and the immune response, allowing recurrence at a later date. Other bacterial species, such as Staphylococcus saprophyticus, Klebsiella pneumonia and Salmonella enterica have also been shown to be invasive in acute UTI. However, the role of intracellular infection in chronic UTI causing more subtle lower urinary tract symptoms (LUTS), a particular problem in the elderly population, is poorly understood. Moreover, the species of bacteria involved remains largely unknown. A previous study of a large cohort of non-acute LUTS patients found that Enterococcus faecalis was frequently found in urine specimens. E. faecalis accounts for a significant proportion of chronic bladder infections worldwide, although the invasive lifestyle of this uropathogen has yet to be reported. Here, we wanted to explore this question in more detail. We harvested urothelial cells shed in response to inflammation and, using advanced imaging techniques, inspected them for signs of bacterial pathology and invasion. We found strong evidence of intracellular E. faecalis harboured within urothelial cells shed from the bladder of LUTS patients. Furthermore, using a culture model system, these patient-isolated strains of E. faecalis were able to invade a transitional carcinoma cell line. In contrast, we found no evidence of cellular invasion by E. coli in the patient cells or the culture model system. Our data show that E. faecalis is highly competent to invade in this context; therefore, these results have implications for both the diagnosis and treatment of chronic LUTS.
What's known on the subject? and What does the study add?• Microscopic pyuria is widely used as a surrogate marker of infection, although there is little data supporting its use in patients who present with non-acute LUTS. The effects of urinary storage, preservation, and the use of laboratory methods to enhance leucocyte detection, are also unclear.• This large, prospective study highlights the poor performance of dipstick urine analysis, and direct microscopy, as surrogate markers of UTI in patients with LUTS. A series of laboratory analyses also examine the effects of urine handling and processing on test integrity, which have important implications for clinical practice. Objective• To evaluate the diagnostic performance of pyuria as a surrogate marker of urinary tract infection (UTI) in patients with chronic lower urinary tract symptoms (LUTS), and determine the impact of sample storage, cytocentrifugation, and staining techniques, on test performance. Patients and Methods• Between 2008 and 2011, we recruited 1223 patients (120 men; 1103 women; mean age 54 years) with one or more LUTS from a specialist urological outpatient service. We conducted a prospective observational study to determine the performance of microscopic pyuria Ն10 wbc/mL as a surrogate marker of UTI in patients with LUTS.• All patients provided clean-catch midstream urine (MSU) samples for analysis, and routine microbiological cultures were used as our reference standard. We also scrutinised the performance of dipstick leucocyte esterase Ն 'trace' in the detection of microscopic pyuria.• The influence of sample handling and processing on test performance was examined in a series of laboratory studies.• The effects of storage on leucocyte decay were determined using repeated microscopic assessments of individual urine samples, to plot temporal changes in leucocyte numbers. This study used varied storage conditions (ª20°C and 4°C), and boric acid preservation.• Paired microscopic assessments were used to determine the effects of centrifugation on leucocyte salvage in spun/unspun samples (relative centrifugal force range 39-157 g). Similar methods were used to assess microscopic leucocyte quantification in stained/unstained urine (Sternheimer-Malbin protocol). Results• The positive predictive value (PPV) and negative predictive value (NPV) of pyuria as a surrogate marker of UTI were 0.40 (95% confidence interval [CI] 0.37-0.43) and 0.75 (95% CI 0.73-0.76), respectively. • The dipstick was unable to identify significant microscopic pyuria (Ն10 wbc/mL) in 60% of the samples: PPV 0.51 (95% CI 0.48-0.55); NPV 0.75 (95% CI 0.73-0.76). Microscopic pyuria performed poorly as a surrogate of UTI defined by bacterial culture.
Midstream urine (MSU) culture remains the gold standard diagnostic test for confirming urinary tract infection (UTI). We previously showed that patients with chronic lower urinary tract symptoms (LUTS) below the diagnostic cutoff on MSU culture may still harbor bacterial infection and that their antibiotic treatment was associated with symptom resolution. Here, we evaluated the results of the United Kingdom’s MSU culture in symptomatic patients and controls. Next, we compared the bacterial enrichment capabilities of the MSU culture with those of a 50-µl uncentrifuged culture, a 30-ml centrifuged sediment culture, and 16S rRNA gene sequencing. This study was conducted on urine specimens from 33 LUTS patients attending their first clinical appointment (mean age, 48.7 years; standard deviation [SD], 16.5 years), 30 LUTS patients on treatment (mean age, 47.8 years; SD, 16.5 years) whose symptoms had relapsed, and 29 asymptomatic controls (mean age, 40.7 years, SD, 15.7 years). We showed that the routine MSU culture, adopting the UK interpretation criteria tailored to acute UTI, failed to detect a variety of bacterial species, including recognized uropathogens. Moreover, the diagnostic MSU culture was unable to discriminate between patients and controls. In contrast, genomic analysis of urine enriched by centrifugation discriminated between the groups, generating a more accurate understanding of species richness. In conclusion, the United Kingdom’s MSU protocol misses a significant proportion of bacteria, which include recognized uropathogens, and may be unsuitable for excluding UTI in patients with LUTS.
Objective To understand health-related issues in women following mesh-augmented prolapse surgery. Design Inductive thematic analysis of free-text comments from participants in a cross-sectional study of laparoscopic mesh sacrohysteropexy. Setting Tertiary urogynaecology centres, United Kingdom. Population Women who underwent laparoscopic mesh sacrohysteropexy by surgeons based at two tertiary urogynaecology centres between 2010 and 2018. Methods A total of 1766 potential participants were contacted by post and invited to complete paper, online or telephone questionnaires containing a free-text comments section. Of 1121 participants (response proportion 63.5%), 752 (67.1%) provided such comments. These were analysed with a six-stage inductive thematic analysis, using NVIVO 11â software. Main outcome measures Themes developed from free-text comments. Results Following familiarisation, 29 codes and 189 sub-codes were identified. These defined six themes: pelvic floor symptoms, health status, treatment success, mesh, pain and care received. The majority of comments centred on the first of these six themes. There were concerns about mesh use and a desire for more information. A range of pain symptoms were mentioned, often associated with pelvic floor symptoms, prolapse surgery or mesh. Conclusions Despite the mesh controversy, pelvic floor symptoms and their impact on quality of life remain the principle concern of women following mesh-augmented prolapse surgery. There is a need for quality, accessible and evidence-based information sources for those women with concerns, and for those considering such surgery in the future, particularly regarding mesh safety and postoperative recovery. The relationships between pain, prolapse, mesh and pelvic floor surgery require further study.
BackgroundAdenosine-5′-triphosphate (ATP) is a neurotransmitter and inflammatory cytokine implicated in the pathophysiology of lower urinary tract disease. ATP additionally reflects microbial biomass thus has potential as a surrogate marker of urinary tract infection (UTI). The optimum clinical sampling method for ATP urinalysis has not been established. We tested the potential of urinary ATP in the assessment of lower urinary tract symptoms, infection and inflammation, and validated sampling methods for clinical practice.MethodsA prospective, blinded, cross-sectional observational study of adult patients presenting with lower urinary tract symptoms (LUTS) and asymptomatic controls, was conducted between October 2009 and October 2012. Urinary ATP was assayed by a luciferin-luciferase method, pyuria counted by microscopy of fresh unspun urine and symptoms assessed using validated questionnaires. The sample collection, storage and processing methods were also validated.Results75 controls and 340 patients with LUTS were grouped as without pyuria (n = 100), pyuria 1-9 wbc μl-1 (n = 120) and pyuria ≥10 wbc μl-1 (n = 120). Urinary ATP was higher in association with female gender, voiding symptoms, pyuria greater than 10 wbc μl-1 and negative MSU culture. ROC curve analysis showed no evidence of diagnostic test potential. The urinary ATP signal decayed with storage at 23°C but was prevented by immediate freezing at ≤ -20°C, without boric acid preservative and without the need to centrifuge urine prior to freezing.ConclusionsUrinary ATP may have a role as a research tool but is unconvincing as a surrogate, clinical diagnostic marker.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.