Potential Biomarkers Utilized to Define and Manage Overactive Bladder Syndrome

Predictive role of neutrophil-percentage-albumin ratio (NPAR) in overactive bladder (OAB) in adults in the United States: a cross-sectional study

BACKGROUND

There is mounting evidence suggesting a direct connection between inflammatory responses and the pathophysiology of overactive bladder (OAB). However, conventional inflammatory markers do not directly indicate a correlation with OAB. Therefore, our goal was to investigate the relationship between OAB and a novel inflammatory marker, the neutrophil percentage-to-plasma-albumin ratio (NPAR).

METHODS

This study included 28,906 participants from the 2005-2018 National Health and Nutrition Examination Survey (NHANES). Weighted multivariate regression models and multiple regression equations were applied to evaluate the correlation between NPAR and OAB. Additionally, to evaluate the possibility of a linear relationship between NPAR and OAB, smoothed curve fitting was used. Sensitivity and stratified analyses were conducted to assess the robustness of the results.

RESULTS

The final sample size consisted of 28,906 individuals, with an overall OAB prevalence of 24.6%. Using a weighted multivariate logistic model and adjusting for multiple covariates, we identified a strong association between NPAR and OAB (OR 1.074, 95% CI 1.06-1.08). Individuals in the highest NPAR quartile had a 32% greater prevalence of OAB compared to those in the lowest quartile. Smoothed curve fitting showed a nonlinear connection between NPAR and OAB, and the effect sizes remained consistent across specific subgroups (P for interaction < 0.05).

CONCLUSION

The incidence of OAB was shown to positively correlate with higher NPAR levels in this investigation. NPAR might be a useful and affordable biomarker for determining who is at risk for OAB, facilitating timely intervention.

Focal or diffuse bladder wall thickness on bladder computed tomography indicates more severe bladder wall inflammation in patients with interstitial cystitis

PURPOSE

The classification of different phenotypes of interstitial cystitis/ bladder pain syndrome (IC/BPS) provides different pathophysiology and associated treatment strategies. Most clinical studies have focused on bladder symptoms and cystoscopic findings. This study analyzed bladder wall thickness (BWT) and compared bladder conditions, urinary biomarkers, and histopathology among patients of IC/BPS with different BWT.

METHODS

A total of 182 patients with cystoscopy-proven IC/BPS underwent abdominal computed tomography (CT) before intervention. The BWT on CT was classified as smooth, focal thickness, and diffuse thickness. Clinical symptoms, urodynamic findings, cystoscopic characteristics, presence of Hunner's lesion, urinary biomarkers, and bladder histopathology were compared among the three subgroups.

RESULTS

Among the patients, 85 had smooth, 64 had focal, and 33 had diffuse BWT. There was a significant trend of patients with focal and diffuse BWT being significantly older with higher symptom scores, smaller bladder capacity, higher grade of glomerulations, and incidence of Hunner's IC. Pathological findings revealed that patients with diffused BWT, followed by those with focal thickness, had the greatest uroepithelial cell denudation and plasma cell infiltration. Patients with diffuse BWT has higher rate of inflammatory cell infiltration, nerve bundle hyperplasia, and granulation tissue. The urinary levels of tumor necrosis factor-alpha and oxidative stress biomarkers in IC/BPS patients with different BWT were significantly higher than those in the controls.

CONCLUSION

BWT in CT scans can reflect chronic inflammation of the bladder wall in patients with IC/BPS, which is clinically relevant for the diagnosis and treatment of IC subtypes.

Urine biomarker could be a useful tool for differential diagnosis of a lower urinary tract dysfunction

A precision diagnosis of lower urinary tract dysfunctions (LUTD) such as bladder outlet obstruction, detrusor overactivity (DO), interstitial cystitis/bladder pain syndrome (IC/BPS), dysfunctional voiding (DV), or detrusor underactivity (DU) needs invasive videourodynamic study. Exploring non-invasive tools to help screening LUTD is necessary for clinicians in their daily practice. This article reviews recently clinical studies of using urinary inflammatory proteins and oxidative stress biomarkers in the identification of specific LUTD among men and women with lower urinary tract symptoms (LUTS). Some important findings have been reported: (1) Using urine chemokines CXCL-1 and interleukin-8 (IL-8), we may discriminate overactive bladder (OAB) symptoms in women between DO and urinary tract infection. (2) Urinary levels of oxidative stress biomarkers such as 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane have a potential being used as a tool to identify women with mixed DO and stress urinary incontinence. (3) Urine levels of total antioxidant capacity (TAC), and prostaglandin E2 (PGE2) are positively correlated with voiding detrusor pressure in patients with DU. (4) Urine levels of brain-derived neurotrophic factor (BDNF) and PGE2 were significantly higher in the DU patients with detrusor function recovery. (5) Women with DV had higher urinary levels of tumor necrosis factor-alpha (TNF-α) and 8-OHdG, and urinary IL-2 level was significantly lower. (6) Urine level of 8-isoprostane was higher in the patients with idiopathic DO and neurogenic DO. (7) Higher urine cytokine levels of monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T-cell expressed and secreted (RANTES), CXCL-10, IL-7, and eotaxin-1 in patients with IC/BPS than controls. (8) The urine levels of IL-8, CXCL-10, BDNF, IL-6, and RANTES were significantly higher in patients with Hunner's IC than non-Hunner's IC. (9) Male patients with IC/BPS had a significantly higher level of eotaxin, MCP-1, TNF-α, 8-OHdG, and TAC. Combining a higher eotaxin and a higher TNF-α can provide a satisfactory diagnostic value in discriminating IC/BPS from other LUTD in men. These studies provide evidence that measurement of cluster of urine biomarkers could be used as a diagnostic tool to differentiate different LUTD in patients with similar LUTS.

Neuro-Urology and Biobanking: An Integrated Approach for Advancing Research and Improving Patient Care

Understanding the molecular mechanisms underlying neuro-urological disorders is crucial for the development of targeted therapeutic interventions. Through the establishment of comprehensive biobanks, researchers can collect and store various biological specimens, including urine, blood, tissue, and DNA samples, to study these mechanisms. In the context of neuro-urology, biobanking facilitates the identification of genetic variations, epigenetic modifications, and gene expression patterns associated with neurogenic lower urinary tract dysfunction. These conditions often present as symptoms of neurological diseases such as Alzheimer's disease, multiple sclerosis, Parkinson's disease, spinal cord injury, and many others. Biobanking of tissue specimens from such patients is essential to understand why these diseases cause the respective symptoms and what can be done to alleviate them. The utilization of high-throughput technologies, such as next-generation sequencing and gene expression profiling, enables researchers to explore the molecular landscape of these conditions in an unprecedented manner. The development of specific and reliable biomarkers resulting from these efforts may help in early detection, accurate diagnosis, and effective monitoring of neuro-urological conditions, leading to improved patient care and management. Furthermore, these biomarkers could potentially facilitate the monitoring of novel therapies currently under investigation in neuro-urological clinical trials. This comprehensive review explores the synergistic integration of neuro-urology and biobanking, with particular emphasis on the translation of biobanking approaches in molecular research in neuro-urology. We discuss the advantages of biobanking in neuro-urological studies, the types of specimens collected and their applications in translational research. Furthermore, we highlight the importance of standardization and quality assurance when collecting samples and discuss challenges that may compromise sample quality and impose limitations on their subsequent utilization. Finally, we give recommendations for sampling in multicenter studies, examine sustainability issues associated with biobanking, and provide future directions for this dynamic field.

Discriminating Different Bladder and Bladder Outlet Dysfunctions by Urinary Biomarkers in Women with Frequency–Urgency Syndrome

Objectives: To investigate the role of urinary biomarkers in discriminating different bladder and bladder outlet dysfunctions in women with frequency–urgency syndrome. Materials and Methods: Urine samples collected from 146 women with frequency–urgency syndrome and 34 controls were investigated. All patients were included in previous clinical trials of functional urology studies and underwent a videourodynamic study. Patients with frequency–urgency syndrome were subdivided into idiopathic detrusor overactivity (IDO), neurogenic detrusor overactivity (NDO), dysfunctional voiding (DV), and hypersensitive bladder (HSB) subgroups. Urine samples were collected before any treatment, and urinary inflammatory proteins (interleukin- (IL-) 1β, IL-2, IL-6, IL-8, tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor (VEGF)), neurogenic proteins (nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and prostaglandin E2 (PGE2)), and oxidative stress biomarkers (8-isoprostane, total antioxidant capacity (TAC), and 8-hydroxydeoxyguanosine (8-OHdG)) were measured and compared between the different OAB subgroups and controls. Results: Of the 146 patients, 31 had IDO, 41 had NDO, 45 had DV, and 29 had HSB. The control group included 34 women. The patients with HSB had lower urinary TAC and IL-2 levels than the controls. The patients with IDO, NDO, and DV had significantly higher urinary TNF-α levels than those with HSB. The patients with IDO and NDO showed an increase in the urinary 8-isoprostane levels, whereas the patients with IDO had higher urinary IL-2, NGF, and BDNF levels than those with NDO. The other urinary inflammatory biomarkers did not show enough significant differences to discriminate between the different bladder and bladder outlet dysfunctions. Conclusions: The urinary levels of inflammatory, neurogenic, and oxidative stress biomarkers varied widely among the patients with bladder and bladder outlet dysfunction. This study’s results provide evidence that women with frequency–urgency syndrome and different urodynamic subtypes have varying bladder inflammation and oxidative stress conditions, which might have an impact on treatment outcomes.

Systematic review of urinary biomarkers of female bladder outlet obstruction (fBOO)

Objective: Diagnosis of bladder outlet obstruction (BOO) in females is often challenging, not only because of the overlap in storage and voiding symptoms in women with various etiologies of lower urinary tract (LUT) dysfunction but also due to the lack of standardized urodynamic criteria to define the condition. There is an unmet need of biologic markers to evaluate BOO in females as an adjunct to other clinical criteria. We sought to elucidate the role of urinary biomarkers in female BOO. Material and methods: We performed a systematic review of studies involving urinary biomarkers in female BOO. The search was performed in PubMed. A total of 58 papers were retrieved and 2 were included for final analysis.Results: Currently, there are no validated biologic markers for female BOO available. Having a biomarker that can be obtained through a urine sample will be an invaluable tool to evaluate and counsel patients with LUT symptoms and possible BOO. The use of NGF as an indicator of BOO in female patients seems to be promising: NGF levels are elevated in women with BOO when compared with normal controls. Conclusions: We found that NGF levels may be applied as a useful biomarker in the diagnosis and evaluation of female patients with BOO symptoms. It will not completely replace other clinical diagnostic tools such as formal urodynamic testing but play a role as a supplement to it. Nevertheless, further studies should be conducted to establish NGF levels as a female BOO biomarker and a routine testing modality.

Performance of urinary biomarkers in differentiating dysfunctional voiding in women with overactive bladder syndrome: a prospective pilot study

PURPOSE

Dysfunctional voiding (DV) in women is a common disorder that causes bladder outlet obstruction (BOO) and may aggravate overactive bladder (OAB) symptoms. The diagnosis of DV relies on clinical alertness and videourodynamic study (VUDS). In this pilot study, we aimed to explore the diagnostic potential of urinary biomarkers in women with DV.

METHODS

Women who visited our institute for the management of OAB were enrolled in this prospective study. Urine samples were collected before treatment and urinary proteins were quantified using enzyme-linked immunosorbent assay (ELISA) kits. Patients with DV and patients with normal tracings were included in the study and control group, respectively. The patients with DV were further divided into two subgroups: those with and those without detrusor overactivity (DO). VUDS parameters and urinary protein levels were compared between each subgroup.

RESULTS

A total of 67 women were enrolled. There were 47 patients with VUDS-diagnosed DV and 20 patients in the control group. Urinary 8-OHdG level (32.65 vs. 15.59, p < 0.001) and urinary TNF-α level (1.43 vs. 0.83, p = 0.031) were significantly higher in the DV group, and urinary IL-2 level (0.29 vs. 0.83, p < 0.001) was significantly lower in the DV group. Among the DV patients, urinary PGE2 level was higher in the DO group (240.4 vs 149.6, p = 0.049).

CONCLUSIONS

In women with DV, urinary 8-OHdG level is elevated compared to women with normal VUDS. Urinary PGE2 level is elevated in patients with DV and DO. These finding suggests increased reactive-oxidative stress response and detrusor hyperactivity in DV patients. Urinary biomarkers can serve as potential non-invasive diagnostic tools in women with OAB.

The use of urinary biomarkers in the diagnosis of overactive bladder in female patients. A systematic review and meta-analysis

INTRODUCTION AND HYPOTHESIS

Nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and other proteins are related to overactive bladder (OAB) syndrome, as their urinary concentrations are significantly different from those of the general non-OAB population. This review aims to systematically assess whether NGF, BDNF, and other urinary by-products can be used as potential biomarkers to manage women with OAB.

METHODS

This was a systematic review and metanalysis that was conducted according to PRISMA guidelines. Studies were identified by electronic search of Medline, Scopus, ScienceDirect, Embase, and Cochrane Register until October 2020. The included studies investigated the correlation of OAB with NGF, BDNF, and other potential biomarkers in symptomatic women and their controls.

RESULTS

Twelve studies (581 female OAB patients and 394 female controls) were included. Urinary NGF, NGF/Cr, BDNF/Cr, ATP/Cr, and PGE2/Cr ratios were identified as potential biomarkers in female OAB patients. Results of the meta-analysis indicated that uNGF [standard mean difference (SMD) 1.45, 95% CI 0.53-2.36], NGF/Cr ratio (SMD 1.23, 95% CI 0.67-1.78), BDNF/Cr ratio (SMD 0.78, 95% CI 0.006-1.50), and BDNF/Cr ratio (RR 0.78, 95% CI 0.006-1.50) were increased in female OAB patients compared to healthy controls, whereas no difference was found for the PGE2/Cr and ATP/Cr ratios. Current data are inadequate to assess any other potential biomarkers, such as urinary MDA, ATP, and cytokines, in the management of OAB in female patients.

CONCLUSIONS

uNGF, NGF/Cr, and BDNF/Cr ratio could be used in the assessment of female OAB patients. Further studies are needed to specify OAB urinary titer levels in OAB subgroups and healthy women and their potential as diagnostic and management tools in OAB women.

Diagnostic value of nerve growth factor in detrusor overactivity: a study on women with mixed urinary incontinence

OBJECTIVE

Urinary incontinence has a profound impact on women's quality of life. Studies have shown that changes in urinary protein levels could be a potential diagnostic biomarker in some urological diseases. The aim of present study is to determine the diagnostic value of nerve growth factor (NGF) in women with mixed urinary incontinence (MUI) as a diagnostic biomarkers of detrusor overactivity (DO).

METHODS

Seventy women aged between 20 and 75 years with MUI were enrolled in this prospective study. All participants underwent urodynamic study. Urine NGF levels were measured using an ELISA method. NGF level was compared between groups using Mann-Whitney U test. Receiver Operator Characteristic (ROC) analysis was employed to evaluate the diagnostic performance of urinary NGF.

RESULTS

The results showed that the median (min, max) of NGF in patients with DO was significantly higher in comparing to its level in women without DO [184.10 (31, 346.60) pg/ml vs. 151.80 (21, 210.70)], respectively (P = 0.035). Using receiver-operator characteristics analysis, the threshold urinary NGF value of 102.00 pg/ml provided a sensitivity of 88% and specificity of 40% in diagnosing DO, PPV of 39.1%, and NPV of 88.2%, positive likelihood ratio 2.18 and negative likelihood ratio of 0.45 (P = 0.02).

CONCLUSION

Based on high sensitivity and low specificity, we can conclude that NGF can be a good tool for ruling out the OAB when the test is negative. However, the future investigations are needed to expand the observed correlation in larger groups of women with DO.

Biomarkers in urinary tract infections - which ones are suitable for diagnostics and follow-up?

Introduction: Urinary tract infections (UTIs) are one of the most common infections worldwide. Under special circumstances, clinicians must rely on laboratory findings, which might have a weak predicting value, misguiding the practitioners and leading to incorrect diagnosis and overuse of antibiotics. Therefore, there is an urgent need for reliable biomarkers in UTIs. Methods: We performed a literature search for biomarkers used in UTIs from January 1999 until May 2020. We used "urinary tract infection" and "biomarker" as the main key words in the PubMed, Medline and Cochrane databases. After peer review, we excluded the duplicates and identified the suitable articles, from which we collected the data and divided the available biomarkers into 5 groups: i) conventional markers; ii) promising, thoroughly studied biomarkers; iii) promising biomarkers that need further studies; iv) biomarkers of unknown significance; v) controversial, not useful markers. Results: We found 131 articles, mostly from the paediatric population. Neutrophil gelatinase-associated lipocalin (NGAL) and interleukins (IL) have a leading role in diagnosing and differentiating UTIs based on a lot of observational, comparative trials. Heparin Binding Protein (HBP), Lactoferrin (LF), Heat-Shock Protein-70 (HSP-70), Human Defensin-5 (HD-5), Lipopolysaccharide Binding Protein (LBP) and mass spectrometry studies are promising, but confirming data are lacking. The measurable components of the innate immune system and local host cell response could be appropriate biomarkers, but their significance is currently unknown. Conclusions: Conventional biomarkers for UTIs have low specificity. The use of urinary NGAL and interleukins could improve the sensitivity and specificity of laboratory diagnosis of UTIs.

The profile of urinary biomarkers in overactive bladder

AIMS

In overactive bladder (OAB) research, different biomarkers have been proposed as diagnostic tools and may be used to create individual patient profiles. Assessing the diagnostic performance of biomarkers would better outline their utility. Therefore, our aim was to investigate the diagnostic value of four urinary biomarkers: human brain derived neurotrophic factor (hBDNF), malondialdehyde (MDA), h nerve growth factor (hNGF) and h 8-hydroxydeoxyguanosine in women with OAB. These are neurotrophins/oxidative stress markers that have been linked to lower urinary tract symptoms.

METHODS

A total of 105 women were included in the study and distributed in two groups: a group with OAB (n = 53) and a control group (n = 50). The levels of the biomarkers were determined using enzyme-linked immunosorbent assay technique and they were compared between the groups. If the Mann-Whitney test demonstrated a statistically significant difference, receiver operating curves (ROC) analysis was undertaken.

RESULTS

When normalized to urinary creatinine, hBDNF, MDA, and hNGF showed significantly increased values in women with OAB as compared to controls, whereas 8-OHdG showed no significant difference. The diagnostic performance of these biomarkers was analyzed based on the area under the ROC curve (AUC). MDA had the highest AUC (0.75), followed by hNGF (0.69) and hBDNF (0.67).

CONCLUSIONS

Our findings suggest that MDA, a relatively novel biomarker in OAB research, has a fair performance as a diagnostic tool for OAB. Moreover, urinary neurotrophins (NGF and BDNF) as biomarkers may have a role in the diagnostic pathways of women with OAB symptoms.

Do urodynamic findings influence the approach to mid-urethral sling surgery for stress urinary incontinence?

Recent press coverage on vaginal mesh surgery has resulted in a change in how patients are counselled, managed and treated in the UK. For stress urinary incontinence surgical procedures such as insertion of tension-free vaginal tape are commonplace and generally performed as a day-case procedure. Effective and successful management of female urinary incontinence is difficult, even when using diagnostic testing where all conservative managements have failed, and this indicates a need to investigate further. Specialist texts in the fields of urology and urogynaecology argue that urodynamics can help inform the success of surgical intervention for stress urinary incontinence. The aim of this review was to look for evidence of practice where urodynamic findings are used to determine the successful outcome of mid-urethral sling surgery in females. A literature search to identify research on this topic was performed with appraisal of qualifying literature. The qualifying research included attitudes towards urodynamic studies among urogynaecologists and urologists, demonstration that urodynamics has been proven to influence changes in diagnosis and surgical approaches, and the capacity for urodynamics to predict successful outcomes in mid-urethral sling surgery. Analysis of the literature found no evidence to suggest that urodynamic findings can be used to determine successful outcomes following mid-urethral sling surgery.

Urinary biomarkers in patients with detrusor underactivity with and without bladder function recovery

PURPOSE

Detrusor underactivity (DU) is frequently encountered in elderly patients. Part of patients with DU might have bladder function recovery after treatment. This study investigated urinary proteins in these DU patients with and without bladder function recovery.

METHODS

A total of 37 patients with chronic urinary retention and urodynamically proven DU were enrolled. After treatment, 24 DU patients had bladder function recovery whereas 13 had not, after 1-year follow-up. Urine collection at baseline was performed, and the urinary protein including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and prostaglandin E2 (PGE2) were measured by ELISA. Twenty urodynamically normal, 34 detrusor overactivity (DO) and 15 detrusor hyperactivity and inadequate contractility (DHIC) patients served as comparative groups.

RESULTS

Urinary NGF levels were significantly higher than normal in patients with DU (9.2 ± 20.3 vs 1.85 ± 2.9 pg/ml, p = 0.037). Urinary BDNF level was only significantly higher in patients with DU than that of the control group (153 ± 199 vs 77.4 ± 47.7 pg/ml, p = 0.033) but not in patients with DHIC or DO. Compared with the control group, the urinary BDNF level was significantly higher in DU patients with bladder function recovery (190 ± 239 pg/ml, p = 0.033) but not in patients without recovery (85.8 ± 43.7 pg/ml, p = 0.612). The PGE2 level was significantly higher than the control group in DU patients with bladder function recovery (1290 ± 836 pg/ml, p < 0.0001) but not in patients without recovery (383 ± 237 pg/ml, p = 0.130).

CONCLUSION

Patients with DU and higher urinary PGE2 and BDNF levels might have a chance to recover bladder function than those with a lower protein level.

The immunohistochemical and urodynamic evaluation towards the collagen-coated and non-coated polypropylene meshes implanted in the pelvic wall of the rats

Our aim is to study the inflammatory response towards the collagen-coated and non-coated polypropylene meshes in rats and the urodynamic investigation post-operatively. Forty-two female Sprague Dawley were divided into 7 groups of 6 rats; Control, Day 7 and 30 for Sham, Avaulta Plus (MPC), Perigee (MP). UDS were taken at days 7 and 30. Mesh with the vagina and bladder wall was removed and sent for immunohistochemical examination. Results showed intense inflammatory reaction on day 7 in the study groups which decreased on day 30. IL-1, TNF-α, MMP-2 and CD31 were observed to decrease from day 7 to day 30. NGF was almost normal on day 30 in all groups. UDS showed no difference in voiding pressure. Both Study and Sham groups had shorter voiding interval (VI) on day 7 but significantly lower in MPC. VI had significantly increased on day 30 in all groups. Voided volume was significantly lower in the mesh groups even when an increase was seen on day 30. In conclusion, the higher levels of IL-1, TNF-α and MMP-2 in collagen-coated polypropylene mesh imply greater inflammation than the non-coated polypropylene mesh. Mesh implantation can lead to shorter voiding interval and smaller bladder capacity.