Comparison of the efficacy of intravaginal electrical stimulation in women with idiopathic overactive bladder naive and refractory to pharmacological agents

INTRODUCTION AND HYPOTHESIS

This study aims to compare the effectiveness of intravaginal electrical stimulation (IVES) with regard to quality of life (QoL) and clinical parameters related to incontinence in women with idiopathic overactive bladder (iOAB) naive or refractory to treatment with pharmacological agents (PhA).

METHODS

In this prospective trial, PhA-naive women were included in Group 1 (n = 24) and women with PhA-resistant iOAB were included in Group 2 (n = 24). IVES was performed 3 days a week, with a total of 24 sessions for 8 weeks. Every session lasted 20 minutes. Women were evaluated for the severity of incontinence (24-hour pad test), pelvic floor muscle (PFM) strength (perineometer), 3-day voiding diary (frequency of voiding, nocturia, incontinence episodes, and the number of pads), symptom severity (OAB-V8), quality of life (IIQ-7), treatment success (positive response rate), cure/improvement rate, and treatment satisfaction.

RESULTS

A statistically significant improvement was found in all parameters for each group at the 8th week compared to the baseline values (p < 0.05). At the 8th week, there were no statistically significant differences in the severity of incontinence, PFM strength, incontinence episodes, nocturia, number of pads, QoL, treatment satisfaction, cure-improvement, or positive response rates between the two groups (p > 0.05). It was found that the frequency of voiding and symptom severity parameters were significantly more improved in Group 1 than in Group 2 (p < 0.05).

CONCLUSIONS

Although IVES was more effective in PhA-naive women with iOAB, it also appears to be an effective treatment in the management of women with PhA-resistant iOAB.

CLINICAL TRIAL REGISTRATION

This study was registered with ClinicalTrials.gov under no. NCT05416450.

Urinary brain-derived neurotrophic factor and nerve growth factor as noninvasive biomarkers of overactive bladder in children

Introduction

Overactive bladder (OAB) is the most common urinary disorder and the leading cause of functional daytime intermittent urinary incontinence in children. The aim of this study was to determine whether urinary brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) concentrations, normalized to urine creatinine, could be used as biomarkers for diagnosis and treatment monitoring of OAB in children.

Materials and methods

Urine samples of 48 pediatric patients with OAB were collected at the start of anticholinergic therapy (baseline), at follow-up visits (3 and 6 months), and from 48 healthy controls. Urinary BDNF and NGF concentrations were determined by ELISA method (Merck, Darmstadt, Germany) and Luminex method (Thermo Fisher Scientific, Waltham, USA). Differences of frequency between quantifiable analyte concentrations between subject groups were determined using Fisher’s exact test.

Results

There was no statistically significant difference between quantifiable analyte concentrations between patients at baseline and the control group for BDNF and NGF by either the ELISA or Luminex method (P = 1.000, P = 0.170, P = 1.000, and P = N/A, respectively). There was a statistically significant difference between quantifiable BDNF by the ELISA method between patients at baseline and complete success follow-up (P = 0.027), while BDNF by Luminex method and NGF by both methods were not statistically significant (P = 0.078, P = 0.519, and P = N/A, respectively).

Conclusions

This study did not demonstrate that urinary BDNF and NGF concentrations, can be used as biomarkers for diagnosis and therapy monitoring of OAB in children.

Could urinary nerve growth factor and bladder wall thickness predict the treatment outcome of children with overactive bladder?

Objective:

Bladder wall thickness (BWTh) measurements and Nerve Growth Factor (NGF) /creatinine (Cr) values, as noninvasive tools, were found to predict daytime voiding problems in children with overactive bladder (OAB). The goal of this research was to examine if bladder wall thickness together with urine NGF/Cr could be a clinical utility in treatment outcome of OAB in children.

Patients and Methods:

A total of 60 children with OAB, (Group 1; n=40) and healthy normal controls (Group 2; n=20), aged 6-14 years old were involved in this prospective study. Children were evaluated with detailed history and physical examination, including neurologic examination, and were asked to complete a self-reported questionnaire and a 3-day bladder diary with the aid of their parents. Uroflowmetry was performed in all cases. Urinary nerve growth factor levels were measured by the ELISA and BWTh was measured trans-abdominally by one uro-radiologist specialized in pediatric ultrasonography. Urinary NGF levels were normalized by urinary creatinine levels and compared among all subgroups. Children with OAB received urotherapy as first line treatment at least for three months. 18 children refractory to urotherapy received anticholinergic therapy defined as group 3.

Results:

The median age of the study group was 10 (range 6 to 16). After urotherapy, 22 children had similar BWTh and NGF/Cr values compared to controls. (2.75 ± 1.15; 2.40 ± 1.00 mm; p=0.86 and 1.02 ± 0.10; 0.78 ± 0.15; p=0.12, respectively). After anticholinergic treatment, BWTh levels (2.25 ± 0.90; 2.40 ± 1.00 mm; p=0.94) and NGF/Cr values (0.95 ± 0.10; 0.78 ± 0.15; p=0.42, respectively) had no significantly difference compared to controls (Group 2).

In receiver operating characteristic analysis, bladder wall thickness was found to have sensitivity of 85% and specificity of 84.2% (3,20 AUC, 913; 95 %) and NGF/Cr had sensitivity of 90% and specificity of 92.1% (1,595; AUC, 947; 95 %) in predicting treatment outcome in children with OAB.

Conclusions:

Bladder wall thickness measurements and NGF/Cr values, as noninvasive tools, could guide outcomes in the treatment of children with overactive bladder.

Correlation between the NGF levels and questionnaire forms in patients receiving antimuscarinic treatment and those receiving onabotulinum toxin-A injection

OBJECTIVE

To compare nerve growth factor (NGF) levels in patients who received antimuscarinic, versus onabotulinum toxin-A (onaBoNT-A) injection, as well as to investigate whether there is a correlation between NGF levels, and 8-item overactive bladder questionnaire(OAB-V8), urogenital distress inventory (UDI)-6, and incontinence impact questionnaire (IIQ)-7 forms.

MATERIAL AND METHODS

Fourty adult patients with OAB were enrolled in this prospective study. An antimuscarinic was prescribed to 20 naive patients, and onaBoNT-A injection was administered to 20 patients, who were refractory to antimuscarinics. Urine samples were obtained before, and after 3^rd and 6^th months of treatment, and NGF levels were measured. Symptom scores of OAB-V8, UDI-6,and IIQ-7 were recorded.

RESULTS

There was no significant difference between groups in terms of the initial OAB-V8, IIQ-7, and UDI-6 scores, whereas NGF values showed no significant difference over time in onaBoNT-A group (p=0.069, p=0.069). NGF levels were significantly lower in 3^rd and 6^th months, in patients receiving antimuscarinic (p=0.003, p=0.007); a strong correlation was found in 3rd month between the NGF levels, OAB-V8 scores (r=0.704, p=0.001), and IIQ-7 scores (r=0.676, p=0.001), and a moderate correlation between NGF levels, and UDI-6 scores (r=0.583, p=0.007). In the 6^th months, a very strong correlation was found between NGF levels, and OAB-V8 scores (r=0.811, p=0.004), and a strong correlation was found between NGF levels, and IIQ-7 scores (r=0.671, p=0.001). In onaBoNT-A group, there was no significant correlation between NGF levels, and other variables.

CONCLUSION

NGF level might be a good marker to evaluate effectiveness of treatment in patients receiving antimuscarinics, owing to correlation of urinary NGF levels with symptom scores. Lack of correlation in patients receiving onaBoNT-A injection could be a result of differences in the mechanism of action.

Genetic variants and expression changes in urgency urinary incontinence: A systematic review

Aim

To perform a systematic review summarizing the knowledge of genetic variants, gene, and protein expression changes in humans and animals associated with urgency urinary incontinence (UUI) and to provide an overview of the known molecular mechanisms related to UUI.

Methods

A systematic search was performed on March 2, 2020, in PubMed, Embase, Web of Science, and the Cochrane library. Retrieved studies were screened for eligibility. The risk of bias was assessed using the ROBINS‐I (human) and SYRCLE (animal) tool. Data were presented in a structured manner and in the case of greater than five studies on a homogeneous outcome, a meta‐analysis was performed.

Results

Altogether, a total of 10,785 records were screened of which 37 studies met the inclusion criteria. Notably, 24/37 studies scored medium‐high to high on risk of bias, affecting the value of the included studies. The analysis of 70 unique genes and proteins and three genome‐wide association studies showed that specific signal transduction pathways and inflammation are associated with UUI. A meta‐analysis on the predictive value of urinary nerve growth factor (NGF) levels showed that increased urinary NGF levels correlate with UUI.

Conclusion

The collective evidence showed the involvement of two molecular mechanisms (signal transduction and inflammation) and NGF in UUI, enhancing our understanding of the pathophysiology of UUI. Unfortunately, the risk of bias was medium‐high to high for most studies and the value of many observations remains unclear. Future studies should focus on elucidating how deficits in the two identified molecular mechanisms contribute to UUI and should avoid bias.

The urothelium, the urinary microbioma and men LUTS: a systematic review

INTRODUCTION

The pathophysiology and management of male patients with lower urinary tract symptoms (LUTS) is still a matter of debate. In the past few years, the urothelium and the urinary microbiota represented important areas of research to improve the understanding and management of these patients. Aim of the present review was to summarize the available data on the urothelium and the microbiota related to male LUTS.

EVIDENCE ACQUISITION

A National Center for Biotechnology Information (NCBI) PubMed search for relevant articles published between January 2000 and December 2019 was performed using the medical subjects heading "urothelium," "microbioma," "microbiota," "urobioma," "urobiota," "benign prostatic hyperplasia," "benign prostatic enlargement," "lower urinary tract symptoms," "lower urinary tract dysfunction," "men," "male," "overactive bladder," "receptors." Exclusion criteria included: animal studies and studies on muscarinic and adrenergic pathways.

EVIDENCE SYNTHESIS

The urothelium has been recently evaluated in humans to evaluate new possible markers and pathways. New possible targets for the treatment of male LUTS include the neural growth factor, the cannabinoid, the vanilloid and the ATP pathways. However, studies in humans are still needed to elucidate the exact role of these pathways in the management of male patients with LUTS. The available evidence on the urinary microbioma in male is poor. Standing to the available, urinary microbioma is evident in healthy urine in males. Moreover, the urinary microbioma varies depending on the method of collection, sexually transmitted disease status, inflammation and urinary symptoms. A possible role of probiotics in the management of LUTS in women has been proposed and may have a role in male patients as well.

CONCLUSIONS

The urothelium and the urinary microbiota are still poorly studied in men with LUTS. Most of the evidence and the hypothesis on the relationship between urothelium/urinary microbiota and LUTS comes from animal/in-vitro evidence while clinical trials are lacking. These pathways seem interesting even in LUTS pathogenesis in men but their possible role as a new therapeutic target is still an open debate.

Association between overactive bladder and serum nerve growth factor concentrations in women with high-grade uterine prolapse

INTRODUCTION AND HYPOTHESIS

The association between overactive bladder (OAB) and uterine prolapse remains unclear. The extent of the role of serum nerve growth factor (NGF) levels in this relationship is also not known. Therefore, our study evaluated the association among OAB, high-grade uterine prolapse and serum NGF levels.

METHODS

A total of 90 patients participated in our study and were grouped as follows. Group I included patients with high-grade uterine prolapse and OAB, group II included patients with only high-grade uterine prolapse, and group III included healthy women without uterine prolapse or OAB. Serum NGF level analysis was performed in all groups.

RESULTS

Serum NGF levels varied greatly among the three groups, with significantly higher levels in group 1 than in groups 2 and 3 (p < 0.001). Serum NGF levels with a cutoff point of 120.49 pg/ml identified women with significant OAB symptoms to discriminate among groups with a sensitivity of 80%, specificity of 86.7%, positive predictive value of 75.0%, negative predictive value of 89.7% and positive likelihood ratio of 6.01 (p < 0.001).

CONCLUSIONS

Our study showed that NGF-related pathways may play an active role in the pathophysiology of OAB with high-grade uterine prolapse patients based on obstruction hypothesis.

A Novel Alternative in the Treatment of Detrusor Overactivity? In Vivo Activity of O-1602, the Newly Synthesized Agonist of GPR55 and GPR18 Cannabinoid Receptors

The aim of the research was to assess the impact of O-1602—novel GPR55 and GPR18 agonist—in the rat model of detrusor overactivity (DO). Additionally, its effect on the level of specific biomarkers was examined. To stimulate DO, 0.75% retinyl acetate (RA) was administered to female rats’ bladders. O-1602, at a single dose of 0.25 mg/kg, was injected intra-arterially during conscious cystometry. Furthermore, heart rate, blood pressure, and urine production were monitored for 24 h, and the impact of O-1602 on the levels of specific biomarkers was evaluated. An exposure of the urothelium to RA changed cystometric parameters and enhanced the biomarker levels. O-1602 did not affect any of the examined cystometric parameters or levels of biomarkers in control rats. However, the O-1602 injection into animals with RA-induced DO ameliorated the symptoms of DO and caused a reversal in the described changes in the concentration of CGRP, OCT₃, BDNF, and NGF to the levels observed in the control, while the values of ERK1/2 and VAChT were significantly lowered compared with the RA-induced DO group, but were still statistically higher than in the control. O-1602 can improve DO, and may serve as a promising novel substance for the pharmacotherapy of bladder diseases.

Biomarkers Implicated in Lower Urinary Tract Symptoms: Systematic Review and Pathway Analyses

PURPOSE

Lower urinary tract symptoms are prevalent and burdensome, yet methods to enhance diagnosis and appropriately guide therapies are lacking. We systematically reviewed the literature for human studies of biomarkers associated with lower urinary tract symptoms.

MATERIALS AND METHODS

PubMed®, EMBASE® and Web of Science® were searched from inception to February 13, 2018. Articles were included if they were in English, performed in benign urological populations without neurological disorders or interstitial cystitis/bladder pain syndrome, and assessed a biomarker's association with or ability to predict specific lower urinary tract symptoms or urological conditions. Bioinformatic pathway analyses were conducted to determine whether individual biomarkers associated with symptoms are present in unifying pathways.

RESULTS

Of 6,150 citations identified 125 met the inclusion criteria. Most studies (93.6%) assessed biomarkers at 1 time point and were cross-sectional in nature. Few studies adjusted for potentially confounding clinical variables or assessed biomarkers in an individual over time. No individual biomarkers are currently validated as diagnostic tools for lower urinary tract symptoms. Compared to controls, pathway analyses identified multiple immune response pathways that were enriched in overactive bladder syndrome and cell migration/cytoskeleton remodeling pathways that were enriched in female stress incontinence.

CONCLUSIONS

Major deficiencies in the existing biomarker literature include poor reproducibility of laboratory data, unclear classification of patients with lower urinary tract symptoms and lack of adjustment for clinical covariates. Despite these limitations we identified multiple putative pathways in which panels of biological markers need further research.

The probability of re-treatment after discontinuation of a 3-month versus a 6-month course of solifenacin for female overactive bladder: A prospective randomized controlled study

OBJECTIVES

The aim of this study is to compare the re-treatment probabilities after a 3-month versus a 6-month course of antimuscarinic treatment for women with overactive bladder syndrome (OAB).

STUDY DESIGN

A prospective randomized controlled study.

MAIN OUTCOME MEASURES

Between-group differences in the probability of re-treatment for OAB between the 3-month and 6-month groups.

METHODS

Women with OAB were randomly allocated to receive solifenacin (5 mg per day) for a treatment interval of either 3 or 6 months.

RESULTS

Ninety-one patients were treated in each group. The probability of re-treatment did not differ between the 3-month and 6-month groups (P = 0.11). Parity (hazard ratio = 1.81, P = 0.001), number of incontinence episodes (hazard ratio = 1.09, P = 0.008) and suboptimal response (hazard ratio = 3.56, P = 0.006) were independent predictors of re-treatment of OAB. Physical limitation, as indicated on the King's Health Questionnaire, was the only independent factor predicting completion of the scheduled treatment period (odds ratio = 1.01, P = 0.008).

CONCLUSIONS

Prolonged antimuscarinic treatment does not decrease the need for re-treatment of OAB. Nonetheless, female patients with increased parity, more severe incontinence and a suboptimal response to antimuscarinic treatment are more likely to seek re-treatment of OAB due to recurrence of symptoms. In addition, patients with more serious physical limitation related to OAB are more likely to complete the scheduled treatment period. These findings could serve as a guide in clinical consultations regarding antimuscarinic treatment and if taken into consideration in future studies could lower the dropout rate.

Urinary Biomarkers in Overactive Bladder: Revisiting the Evidence in 2019

CONTEXT

In overactive bladder (OAB), after an initial outbreak of research, it is more consensual that biomarkers may be better used to phenotype patients. Herein, we revisit this topic, including some of the most promising biomarkers.

OBJECTIVE

To provide a comprehensive analysis of the actual role of biomarkers in OAB.

EVIDENCE ACQUISITION

A PubMed-based literature search was conducted, including the most relevant articles published in the last 15 yr, on nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), adenosine triphosphate (ATP), genomics, and microbiota as OAB biomarkers. Articles with no full text available or not written in English were excluded. Additional reviews were included.

EVIDENCE SYNTHESIS

Urinary NGF, BDNF, and ATP are increased in many OAB patients. These biomarkers can help identify OAB phenotypes and select the ideal candidates for new therapies directed to neurotrophic and purinergic pathways. Circulating urinary miRNA may be useful for establishing the ideal moment for bladder outlet obstruction relief and will eventually lead to the development of therapeutic agents that inhibit or reverse fibrotic pathways in the bladder. Urinary microbiota seems to be related to OAB symptoms, in particular urgency urinary incontinence, and may have strong implications in the prevention, diagnosis, and treatment of OAB.

CONCLUSIONS

In the future, physicians may consider the use of biomarkers to identify distinct OAB phenotypes, with distinct causal mechanisms, selecting patients for specific target therapies with expected better outcomes.

PATIENT SUMMARY

Overactive bladder biomarkers can be useful for phenotype patients and for selecting more effective target therapies.

Urinary Nerve Growth Factor Can Predict Therapeutic Efficacy in Children With Overactive Bladder

OBJECTIVE

To assess urinary nerve growth factor (NGF) in children with overactive bladder (OAB) and to investigate the relationship between urinary NGF/creatinine (Cr) levels and OAB.

PATIENTS AND METHODS

Thirty-five children (27 boys and 8 girls) with OAB and 11 children (6 boys and 5 girls) without OAB or any other urinary symptoms, who served as controls, were included in this study. Urinary NGF levels were measured using enzyme-linked immunosorbent assay. The total urinary NGF levels were adjusted with the concentration of urinary creatinine (NGF/Cr level). Refractory OAB was defined as little improvement in OAB symptoms despite at least 3 months of urotherapy and anticholinergic agent treatment. Urinary NGF/Cr was compared between the children with OAB and the controls. The relationship between urinary NGF/Cr and treatment outcomes was also evaluated.

RESULTS

Urinary NGF/Cr was significantly higher in the children with OAB when compared with those in the control group (0.65 ± 0.82 vs 0.11 ± 0.09, P = .0007). Improvement of OAB symptoms was observed in 26 out of 35 children (74%). The remaining 9 children showed refractory OAB symptoms (the refractory group). Urinary NGF/Cr was significantly higher in the refractory group than in the improved group (1.28 ± 1.34 vs 0.44 ± 0.39, P = .027).

CONCLUSION

Urinary NGF/Cr was significantly higher in the children with OAB than in the controls, and was significantly higher in the refractory group than in the improved group. Urinary NGF/Cr could not only be a potential biomarker for children with OAB, but also a predictor of therapeutic efficacy in children with OAB.

Efficacy of Transcutaneous Electrical Nerve Stimulation in the Treatment of Overactive Bladder

INTRODUCTION

Overactive Bladder (OAB) accounts for 40-70% cases of incontinence. The etiology is unknown though detrusor instability is found in urodynamic evaluation of almost all cases. Detrusor instability or hyperreflexia can be inhibited by direct inhibition of impulses in the pre-ganglionic afferent neuron or by inhibition of bladder pre-ganglionic neurons of the efferent limb of micturition reflex. Transcutaneous Electrical Nerve Stimulation (TENS) is based on the gate control theory of abolishing the local micturition reflex arc.

AIM

To assess the effectiveness and safety of TENS in idiopathic OAB.

MATERIALS AND METHODS

It is a prospective experimental study to evaluate the effectiveness of TENS v/s placebo in reducing OAB symptoms. (n1=20, n2 =20). Ten treatment sessions (5 sessions/week) of 30 minutes, were conducted.

RESULTS

There was a significant improvement in Overactive Bladder Symptom Scores (OABSS) in TENS group and 2 patients were completely dry following TENS therapy.

CONCLUSION

In elderly women, patients with OAB where other co-medications have their own anticholinergic side effects and impairment of cognition is a concern, TENS can be a useful intervention. TENS units are safe, economical and easily commercially available.

Urinary tract infections in women with urogynaecological symptoms

PURPOSE OF REVIEW

Urinary tract infections are common in the field of urogynaecology. Women with persistent urinary symptoms seem more likely to have bacteriuria despite negative cultures. In this review, we will give an overview of the recent insights on the relationship between urinary tract infection and persistent urinary symptoms and possible new therapeutic options.

RECENT FINDINGS

Recently published articles evaluated the prevalence of low-count bacteriuria (≥10 CFU/ml) or intracellular bacterial communities in women with overactive bladder symptoms (OAB). Differences in urinary microbioma observed in women with and without OAB symptoms were evaluated. In the light of these findings, current screening strategies were discussed and alternative screening methods for bacteriuria developed.

SUMMARY

Low-count bacteriuria (≥10 CFU/ml) seems to be more prevalent in women with OAB. Also intracellular bacterial communities are more commonly detected in these women. The microbioma found in women with urinary symptoms appeared to differ from healthy controls. The current screening methods might be insufficient as they are targeted at detecting uropathogenic Escherichia coli, mostly using a detection threshold of at least 10 CFU/ml and failing to detect intracellular bacterial communities. Studies evaluating the efficacy of treating women with low-count bacteriuria are limited but promising.

Frequent nocturia episodes, a suboptimal response to treatment, and small bladder capacity predict the need for persistent antimuscarinic therapy or re-treatment after discontinuation of antimuscarinics in female overactive bladder

OBJECTIVE

The aim of the study was to investigate predictive factors of the need for persistent antimuscarinic therapy or re-treatment (PR) after discontinuation of antimuscarinic therapy for women with overactive bladder syndrome (OAB).

METHODS

All consecutive OAB women were enrolled in a prospective cohort study, and treated with solifenacin for 12 weeks in a University Hospital. Factors affecting PR were analyzed by Cox regression analysis.

RESULTS

A total of 122 women were enrolled, and 107 women underwent 12-week solifenacin treatment. The dropout rate was 12.3%. The median follow-up period was 20.4 weeks (25-75 interquartile range: 16-102.3 wk). Twenty-seven (25%) women had PR. The median PR-free interval was 125.4 weeks (95% CI = 58.4 to - wk). Nocturia episodes (hazard ratio = 1.54), a suboptimal response (hazard ratio = 2.53), and the strong-desire volume (hazard ratio = 0.992) were independent predictors of PR by Cox backward stepwise regression analysis. The areas under the receiver-operating characteristic curves for nocturia episodes, a suboptimal response, and the strong-desire volume to predict PR were only 0.65, 0.63, and 0.59, respectively. In addition, normalized urinary nerve growth factor level was not significant (hazard ratio = 1.005, P = 0.68) for predicting PR. Furthermore, normalized urodynamic findings did not correlate with PR, a suboptimal response, or changes of Overactive Bladder Symptom Score and urinary nerve growth factor level.

CONCLUSIONS

Frequent nocturia episodes, a suboptimal response, and small bladder capacity may predict PR after solifenacin treatment. These findings may serve as an initial guide in consultation regarding the treatment of OAB.

Does central sensitization help explain idiopathic overactive bladder?

The pathophysiological mechanisms underlying overactive bladder syndrome (OAB) can include dysfunction of sensory pathways of the peripheral and central nervous systems, resulting in bladder hypersensitivity. Central sensitization describes an induced state of spinal hypersensitivity that is associated with a variety of chronic pain disorders that share many attributes with OAB, albeit without the presence of pain. As such, the concept of central sensitization might be relevant to understanding the mechanisms and clinical manifestations of OAB syndrome. An understanding of the pathophysiology and clinical manifestations of central sensitization, and the evidence that supports a role of central sensitization in OAB, including the potential implications of mechanisms of central sensitization for the treatment of patients with OAB could provide a novel approach to the treatment of patients with this disease. Such an approach would be especially relevant to those patients with central sensitization-related comorbidities, and has the potential to improve the outcomes of these patients in particular.

A multiplexed analysis approach identifies new association of inflammatory proteins in patients with overactive bladder

Overactive bladder (OAB) is a common debilitating bladder condition with unknown etiology and limited diagnostic modalities. Here, we explored a novel high-throughput and unbiased multiplex approach with cellular and molecular components in a well-characterized patient cohort to identify biomarkers that could be reliably used to distinguish OAB from controls or provide insights into underlying etiology. As a secondary analysis, we determined whether this method could discriminate between OAB and other chronic bladder conditions. We analyzed plasma samples from healthy volunteers (n = 19) and patients diagnosed with OAB, interstitial cystitis/bladder pain syndrome (IC/BPS), or urinary tract infections (UTI; n = 51) for proinflammatory, chemokine, cytokine, angiogenesis, and vascular injury factors using Meso Scale Discovery (MSD) analysis and urinary cytological analysis. Wilcoxon rank-sum tests were used to perform univariate and multivariate comparisons between patient groups (controls, OAB, IC/BPS, and UTI). Multivariate logistic regression models were fit for each MSD analyte on 1) OAB patients and controls, 2) OAB and IC/BPS patients, and 3) OAB and UTI patients. Age, race, and sex were included as independent variables in all multivariate analysis. Receiver operating characteristic (ROC) curves were generated to determine the diagnostic potential of a given analyte. Our findings demonstrate that five analytes, i.e., interleukin 4, TNF-α, macrophage inflammatory protein-1β, serum amyloid A, and Tie2 can reliably differentiate OAB relative to controls and can be used to distinguish OAB from the other conditions. Together, our pilot study suggests a molecular imbalance in inflammatory proteins may contribute to OAB pathogenesis.

Potential Biomarkers Utilized to Define and Manage Overactive Bladder Syndrome

Clinical diagnosis of overactive bladder (OAB) syndrome has great variation and usually can only be based on subjective symptoms. Measurement of urgency severity score in adjunct with voiding diary may reflect the occurrence of OAB and incontinence severity in daily life. Urodynamic study can detect detrusor overactivity (DO), but not in all OAB patients. A more objective way and less invasive tool to diagnose and assess therapeutic outcome in OAB patients is needed. Recent investigations of the potential biomarkers for OAB include urinary and serum biomarkers and bladder wall thickness. Evidence has also shown that urinary proteins, such as nerve growth factor (NGF) and prostaglandin E2 (PGE2 ) levels increase in patients with OAB, bladder outlet obstruction (BOO) and DO. Patients with OAB have significantly higher urinary NGFlevels and urinary NGF levels decrease after antimuscarinic therapy and further decrease after detrusor botulinum toxin injections. However, the sensitivity of single urinary protein in the diagnosis of OAB is not high and several lower urinary tract diseases may also have elevated urinary NGF levels. Searching for a group of inflammatory biomarkers by microsphere-based array in urine might be a better method in differential diagnosis of OAB from interstitial cystitis, urinary tract infection (UTI) or urolithiasis. Bladder wall thickness has been widely investigated in the diagnosis of BOO and pediatric voiding dysfunction.The role of bladder wall thickness in the diagnosis of OAB, however, has not reach a consistent conclusion. We hereby review the latest medical advances in this field.

Potential urine and serum biomarkers for patients with bladder pain syndrome/interstitial cystitis

There is a lack of consensus on the pathophysiology of bladder pain syndrome/interstitial cystitis. The chronic pain symptoms of bladder pain syndrome/interstitial cystitis refractory to local treatment could be a result of central nervous system sensitization and persisting abnormalities in the bladder wall, which activate the afferent sensory system. Evidence also shows that bladder pain syndrome/interstitial cystitis is a heterogeneous syndrome and that the two subtypes, the ulcerative (classic) and non-ulcerative types, represent different disease entities. There is a need for non-invasive markers for the differential diagnoses of the subtypes of bladder pain syndrome/interstitial cystitis, and between bladder pain syndrome/interstitial cystitis and bladder sensory disorders, such as hypersensitive bladder syndrome or overactive bladder. Bladder pain syndrome/interstitial cystitis, but not overactive bladder, involves an aberrant differentiation program in the bladder urothelium that leads to altered synthesis of several proteoglycans, cell adhesion and tight junction proteins, and bacterial defense molecules. These findings have led to the rationale for identifying urinary biomarkers to detect bladder pain syndrome/interstitial cystitis in patients with frequency urgency syndrome. Recently, the markers that have been the focus of the most research are antiproliferative factor, epidermal growth factor, heparin-binding epidermal growth factor, glycosaminoglycans and bladder nitric oxide. In addition, inflammatory proteins in the urine and serum play important roles in the pathogenesis of bladder pain syndrome/interstitial cystitis. The urinary proteome is an easily accessible source of biomarkers for differentiation between inflammatory bladder disorders. Analysis of multiple urinary proteins and serum cytokines could provide a diagnostic basis for bladder pain syndrome/interstitial cystitis, and could be a tool for the differential diagnosis of bladder pain syndrome/interstitial cystitis and other sensory bladder disorders.

Refractory overactive bladder: a common problem?

INTRODUCTION AND HYPOTHESIS

Unsatisfactory treatment outcome sometimes is described as frequently occurring in patients treated with first-line therapy for overactive bladder (OAB). The present article reviews the different circumstances which may result in failure to respond to lifestyle interventions, behavioral therapy, and/or antimuscarinic treatment.

METHODS

An extensive literature search was conducted to identify relevant articles on pathophysiological, clinical, and pharmacological aspects of refractory OAB.

RESULTS

Missing definition, unrealistic individual expectation of treatment outcomes, lack of communication between physician and patient as well as pathophysiological and pharmacological processes were identified as relevant for failure to respond to first-line OAB treatment. Increase of patient's motivation to adhere to the prescribed treatment, critical examination of the patient in regard to the initial diagnosis, and individual adjustment of antimuscarinic therapy may be appropriate tools to improve treatment outcome in OAB patients.

CONCLUSIONS

Overall, the incidence of refractory OAB seems to be overestimated. There are several approaches to improve therapy results.

Biomarkers in lower urinary tract symptoms/overactive bladder: a critical overview

PURPOSE OF REVIEW

Biomarkers constitute objectively measurable characteristics that can be evaluated as indicators of physiological and pathogenic processes and might be used as diagnostic, prognostic or predictive tools in clinical care. This review examines the availability of biomarkers to treat the dynamic and complex symptoms of overactive bladder (OAB).

RECENT FINDINGS

OAB biomarkers may contribute to reveal the origin of storage symptoms in otherwise healthy individuals. The research encompassing the changes that occur in the bladder or in the peripheral (and central) nervous system might be determined through blood or urinary molecules (neurotrophins, ATP, prostaglandins, C-reactive protein and cytokines) or the measurement of events occurring in the bladder wall (bladder wall or detrusor wall thickness, oxyhemoglobin and deoxyhemoglobin concentration). These biomarkers might contribute to a better understanding of the pathophysiologic mechanisms underlying OAB.

SUMMARY

The word biomarker to name all the parameters described above, from bladder wall thickness to urinary molecules, has been introduced to call the attention to a field wherein objective noninvasive parameters were nonexistent. OAB treatment based on a biomarker, in comparison to the treatment based on a diagnosis made from a careful history and exclusion of urinary tract infection, is not supported by current literature.

Urgency and pain in patients with overactive bladder and bladder pain syndrome. What are the differences?

BACKGROUND

The Overactive Bladder Syndrome (OAB) and the Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) are different urological conditions sharing 'urgency' as a common symptom. The aim of this review is to address our existing knowledge and establish how these symptoms are interrelated and to determine whether or not there is a common link between both symptoms complexes that help to distinguish one from the other.

METHODS

Pubmed was used to obtain references for this non-systematic review aiming to discuss differences between OAB and BPS/IC. Guidelines of several professional associations and discussions based on expert opinion from the authors were implemented.

RESULTS

Whilst in BPS the hallmark symptom is pain on bladder filling, urgency is the defining symptom of OAB. Whilst it is likely that the pain in BPS/IC arises from local inflammation in the bladder wall, the nature of urgency as a symptom, its origin, and the relationship between urgency and pain, as well as the different afferent mechanisms associated with the genesis of these sensory symptoms, remains unknown. Although the aetiology of both OAB and PBS/IC is unclear, the influence of environmental factors has been suggested. Both are chronic conditions with very variable symptom resolution and response to therapy. The relationship with voiding dysfunction, gynaecological causes of chronic pelvic pain or the possible alteration of the hypothalamic-pituitary-adrenal axis and psychological disorders has not been established. Inflammation has been suggested as the common link between OAB and BPS/IC.

CONCLUSIONS

OAB and BPS/IC are different symptoms complexes that share urgency as a common symptom. None of them have a specific symptom although pain on bladder filling is the hallmark symptom in BPS/IC. Bladder pain with urgency should be a trigger for referral to the provider with appropriate knowledge and expertise in this disease state, whereas the management of OAB should be part of normal routine care in the community.

Increased serum C-reactive protein level is associated with increased storage lower urinary tract symptoms in men with benign prostatic hyperplasia

Objective

Chronic inflammation is considered as one of the contributing mechanisms of lower urinary tract symptoms (LUTS). Serum C-reactive protein (CRP) level is the widely used biomarker of inflammatory status. This study investigated the association between serum CRP level in men with benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS) before and after medical treatment.

Methods

A total of 853 men with BPH and LUTS were enrolled. All patients completed the International Prostate Symptoms Score (IPSS) questionnaire and urological examinations. The parameters of uroflowmetry (maximum flow rate, Qmax; voided volume, VV), post-void residual (PVR), total prostate volume (TPV) and transition zone index (TZI), serum prostate specific antigen (PSA), and serum CRP levels were obtained. All patients were treated with alpha-blocker or antimuscarinic agent based on the IPSS voiding to storage subscore ratio (IPSS-V/S). Correlation analyses were performed between serum CRP levels with age, IPSS, TPV, TZI, Qmax, PVR, VV, PSA and between baseline and post treatment.

Results

The mean age was 66.9±11.6 years old and the mean serum CRP levels were 0.31±0.43 mg/dL. Univariate analyses revealed serum CRP levels were significantly associated with age (p<0.001), PSA levels (p = 0.005) and VV (p = 0.017), but not significantly associated with TPV (p = 0.854) or PVR (p = 0.068). CRP levels were positively associated with urgency (p<0.001) and nocturia (p<0.001) subscore of IPSS, total IPSS (p = 0.008) and storage IPSS (p<0.001) and negatively associated with IPSS- V/S ratio (p = 0.014). Multivariate analyses revealed that serum CRP levels were significantly associated with age (p = 0.004) and storage IPSS subscore p<0.001). Patients with IPSS-V/S<1 and treated with tolterodine for 3 months had significant decrease of CRP levels after treatment.

Conclusion

Serum CRP levels are associated with storage LUTS and sensory bladder disorders, suggesting chronic inflammation might play a role in the patients with storage predominant LUTS.

Increased serum adipokines implicate chronic inflammation in the pathogenesis of overactive bladder syndrome refractory to antimuscarinic therapy

OBJECTIVES

Recent studies have shown that chronic inflammation is involved in overactive bladder (OAB) syndrome. OAB could be a subtype of neurogenic inflammation. This pilot study investigated serum adipokine levels in patients with OAB refractory to antimuscarinic therapy.

METHODS

Thirty consecutive patients with OAB-dry (n = 16) or OAB-wet (n = 14) refractory to previous antimuscarinic treatment were prospectively enrolled in this study, a group of 26 normal subjects without lower urinary tract symptoms served as controls. Concentrations of serum C-reactive protein (CRP), nerve growth factor (NGF), and adipokines including interleukins ([IL], IL-1β, IL-6, IL-8), tumor necrosis factor (TNF)-α, monocyte chemotactic protein (MCP)-1, insulin, and leptin were quantified using a bead-based human serum adipokine panel B kit. Data were analyzed using the LX 200 platform. Patients were further classified as having dry or wet OAB and having medical diseases or not. The serum CRP, NGF, and adipokine levels were compared between OAB patients and the controls, and between OAB subgroups.

RESULTS

The serum concentrations of CRP, NGF, IL-1β, IL-6, IL-8, and TNF-α in OAB-dry and OAB-wet patients were significantly higher than among the controls. There was no significant difference in adipokine levels between OAB-dry and OAB-wet, or between OAB patients with and without medical diseases. Serum CRP and NGF levels were significantly higher only in OAB-wet or OAB patients with medical diseases than among controls. The MCP-1 levels, on the other hand, were significantly higher in OAB-dry or OAB patients with disease, than the controls.

CONCLUSIONS

Both OAB-dry and OAB-wet patients showed increased serum CRP, NGF, and adipokine levels compared with the controls, suggesting chronic inflammation of the bladder involving both peripheral and central mechanisms in all OAB patients refractory to antimuscarinic therapy. The increased serum adipokine levels were not relevant to medical diseases.

Neurotrophins in bladder function: what do we know and where do we go from here?

AIMS

Neurotrophins (NTs) have attracted considerable attention in the urologic community. The reason for this resides in the recognition of their ability to induce plastic changes of the neuronal circuits that govern bladder function. In many pathologic states, urinary symptoms, including urgency and urinary frequency, reflect abnormal activity of bladder sensory afferents that results from neuroplastic changes. Accordingly, in pathologies associated with increased sensory input, such as the overactive bladder syndrome (OAB) or bladder pain syndrome/interstitial cystitis (BPS/IC), significant amounts of NTs have been found in the bladder wall.

METHODS

Here, current knowledge about the importance of NTs in bladder function will be reviewed, with a focus on the most well-studied NTs, nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF).

RESULTS

Both NTs are present in the bladder and regulate bladder sensory afferents and urothelial cells. Experimental models of bladder dysfunction show that upregulation of these NTs is strongly linked to bladder hyperactivity and, in some cases, pain. NT manipulation has been tested in animal models of bladder dysfunction, and recently, NGF downregulation, achieved by administration of a monoclonal antibody, has also been tested in patients with BPS/IC and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). NTs have also been found in high quantities in the urine of OAB and BPS/IC patients, raising the possibility of NTs serving as biomarkers.

CONCLUSIONS

Available data show that our knowledge of NTs has greatly increased in recent years and that some results may have future clinical application.

Nerve growth factor (NGF): a potential urinary biomarker for overactive bladder syndrome (OAB)?

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The search for a biomarker in overactive bladder syndrome (OAB) is an emerging field of interest, as bladder dysfunction is a common complaint that causes significant morbidity. A biomarker may give us insight as a diagnostic tool, and also inform us about how severe the condition is, how it may progress and how it may best be treated. The protein of interest here is nerve growth factor (NGF) and it has been shown to be a dynamic molecule in the bladder of patients with OAB. Urinary levels have been seen to rise in patients with OAB and fall in those who respond to treatment. However, there have also been many studies that examine this trend in numerous other conditions, e.g. interstitial cystitis, bladder outflow obstruction, renal stone disease and patients with neurological impairment after stroke. As a result the specificity of this as a potential urinary biomarker for OAB is questioned. This is a review of published studies, which discusses the pros and cons of NGF as a potential urinary biomarker. The evidence is examined and the studies are summarised together in a Table. Questions remain about the reliability, practicality and specificity of NGF as a biomarker for OAB. These questions need to be addressed by further studies that could clarify the points raised.

OBJECTIVE

To review the current literature on the use of urinary nerve growth factor (NGF) as a potential biomarker for overactive bladder syndrome (OAB).

METHOD

A comprehensive electronic literature search was conducted using the PubMed database to identify publications relating to urinary NGF.

RESULTS

There are a growing number of publications that have measured urinary NGF levels in different types of bladder dysfunction. These range from OAB, bladder pain syndrome, idiopathic and neurogenic detrusor overactivity, bladder oversensitivity and bladder outflow obstruction. Urinary NGF levels do appear to be raised in these pathological states when compared with healthy control samples. In patients with OAB, these raised urinary NGF levels appear to also reduce after successful treatment with antimuscarinics and botulinum toxin A, which indicates a potential use in monitoring responses to treatment. However, raised levels are not limited to OAB, which questions its specificity. Urinary NGF measurements are performed with an enzyme-linked immunosorbent assay using polyclonal antibodies to NGF. The technique requires standardisation, and the different antibodies to NGF require validating. Also a definition of what is the 'normal' range of NGF in urine is still required before it can be used as a diagnostic and prognostic tool.

CONCLUSIONS

Whilst the evidence for an increased urinary NGF in OAB appears convincing, many questions about its validity remain including: specificity, sensitivity, cost- and time-effectiveness. Many criteria for what constitutes a biomarker still need to be evaluated and met before this molecule can be considered for this role.

Medical attendance for lower urinary tract symptoms is associated with subsequent increased risk of outpatient visits and hospitalizations based on a nationwide population-based database

Introduction

Lower urinary tract symptoms (LUTS), which encompass storage, voiding, and postmicturition symptoms, are highly prevalent and recognized globally. Based on a nationwide population-based database, this study tests the hypothesis that medical attendance for LUTS is associated with a subsequent increase in the number of outpatient visits and hospitalizations, with differences among medical specialties and age groups.

Methods

Participants were selected from a random population sample of approximately one million people as a representative cohort of National Health Insurance (NHI) enrollees in Taiwan. Participants had at least three outpatient service claims with a coding of LUTS during the recruitment period 2001–2004. Both the LUTS group and non-LUTS control group were monitored for subsequent outpatient visits and hospitalizations, excluding LUTS-related healthcare services, for 2 years following the index date. The results were categorized based on medical specialty and age group.

Results

The outpatient visit rates (no. per person-year) and adjusted incidence rate ratios (IRRs) (95% confidence interval (CI) were significantly higher in urology (4.51, 95%CI 4.15–4.91) and gynecology (1.82, 95%CI 1.76–1.89) for the LUTS group. They were also significantly high in other departments, including internal medicine (1.25), general practice (1.13), Chinese medicine (1.77), family medicine (1.19), surgery (1.38), and psychiatry (1.98). Similarly, the hospitalization rate (no. per 1000 person-year) and adjusted IRRs (95% CI) were significantly higher in urology (5.50, 95% CI = 4.60–6.50) and gynecology (1.60, 95% CI = 1.35–1.90), as well as in internal medicine (1.55) and surgery (1.56), but not in psychiatry (1.12). Furthermore, the IRRs differed among 3 age groups.

Conclusions

A significantly higher number of outpatient visits and hospitalizations were observed for individuals with LUTS, compared to the control group, and the effects differed with the advancement of age. This study broadens understanding of LUTS by viewing their impact on healthcare services with multiple and overlapping systems, rather than considering them exclusively as symptoms of traditional diseases of the bladder and urethra.

Changes in nerve growth factor level and symptom severity following antibiotic treatment for refractory overactive bladder

INTRODUCTION AND HYPOTHESIS

Overactive bladder (OAB) has a multifactorial aetiology, and for some women symptoms may be associated with chronic urothelial inflammation secondary to bacterial colonisation. One marker of such inflammation may be urinary nerve growth factor (NGF). We hypothesised that for women with OAB and urothelial inflammation, urinary NGF would be reduced following antibiotic therapy.

METHODS

Women with overactive bladder and urodynamic diagnosis of detrusor overactivity who were refractory to anticholinergics, and had histological evidence of urothelial inflammation were treated with a 6-week course of rotating antibiotics. Urinary NGF was measured by ELISA before and after treatment. Three-day bladder diaries, the Patients' Perception of Intensity of Urgency Scale, the King's Health Questionnaire and the Patients' Perception of Bladder Condition questionnaire were used to assess subjective and objective outcomes of therapy.

RESULTS

Thirty-nine women with refractory DO were recruited. The NGF levels decreased significantly after antibiotic therapy (Wilcoxon signed rank test; p = 0.015). There were significant improvements in daytime frequency, nocturia and urgency (p < 0.05), and 74 % of women reported improvement in perception of their bladder condition.

CONCLUSIONS

Urinary NGF is responsive to antibiotic therapy. Women with refractory overactive bladder and elevated NGF may benefit from antibiotic treatment.

Biomarkers in overactive bladder

A biomarker is an indicator of a particular disease. It is generally used to define the presence (diagnostic biomarker), severity, progression (prognostic biomarker) of a condition and/or its response to a specific treatment (predictive biomarker). Biomarkers can be specific cells, enzymes, hormones, genes or gene products, which can be detected and measured in parts of the body such as blood, urine or tissue. Therefore, biomarkers have been suggested to play an important role in both the clinical assessment and the management of patients, as well as in the research setting. Recently, interest has gathered in urinary biomarkers as a tool to assess overactive bladder (OAB), potentially playing a role in the diagnosis, disease progression and monitoring response to treatment. Urinary biomarkers identified so far include nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), prostaglandins, cytokines and C-reactive protein. The aim of this review was to review the published literature on biomarkers in OAB. A literature review using Pub Med, clinicaltrials.gov and the controlled trials online registries was performed from 1970 up to June 2012. The search keywords were: the International Continence Society (ICS) definition of "OAB", "nerve growth fac- tor" (NGF), "brain derived growth factor" (BDNF), "prostaglandins," "cytokines," "genetic biomarkers" and "C reactive protein".The results were limited for fully published English-language articles. The search was then subsequently expanded to include urinary biomarkers in interstitial cystitis and bladder pain where relevant. Each of the studies/articles was reviewed, interpreted and discussed to consider the role of urinary biomarkers in OAB. Using the search criteria, a total of 20 studies (animal and human) that investigated the role of urinary biomarkers in OAB were identified. Full text versions of these articles were obtained and reviewed. Studies on NGF suggested that urinary levels were higher in OAB patients and decreased with antimuscarinic and botulinum toxin treatment. BDNF studies have demonstrated raised levels in OAB and also increased levels in situations of acute bladder inflammation. The role of urinary prostaglandins, cytokines and CRP does not appear to be specific to the OAB disease process according to the current available evidence. Based on the evidence so far NGF and BDNF appear to be the most promising biomarkers in OAB. Although still in their infancy these neurotrophic factors could potentially diagnose OAB, replacing urodynamics and aiding in monitoring disease progression and response to treatment in addition to clinical symptoms.