Pain reduction realized with extracorporeal shock wave therapy for the treatment of symptoms associated with interstitial cystitis/bladder pain syndrome—A prospective, multicenter, randomized, double‐blind, placebo‐controlled study

The Pathomechanism and Current Treatments for Chronic Interstitial Cystitis and Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic and debilitating condition characterized by symptoms such as bladder pain, frequent urination, and nocturia. Pain is typically perceived in the lower abdomen, pelvic floor, or urethra, causing significant discomfort and impacting quality of life. Due to the similarity of its symptoms with those of overactive bladder and acute bacterial cystitis, patients often face misdiagnosis and delayed appropriate treatment. Hunner's (HIC) and non-Hunner's IC (NHIC), each with distinct clinical presentations, urothelial dysfunction, chronic inflammation, and central sensitization and thus multimodal symptomatic treatment approaches, may be the most common pathogeneses of IC/BPS. Treatment of IC/BPS should involve identifying the different clinical phenotypes and underlying pathophysiology causing clinical symptoms and developing strategies tailored to the patient's needs. This review discusses the roles of urine biomarkers, bladder inflammation, and glycosaminoglycans in the pathogenesis of IC/BPS. Various bladder treatment modalities are explored, including glycosaminoglycan replenishment, botulinum toxin A injection, platelet-rich plasma injection, low-energy shock waves, immunosuppression, and low-dose oral prednisolone. Pelvic floor muscle physiotherapy and bladder therapy combined with psychiatric consultation can help alleviate psychological stress and enhance the quality of life of patients with IC/BPS. Elucidating the pathological mechanisms and exploring diverse treatment options would help advance the care of individuals suffering from this challenging bladder condition.

Definition Change and Update of Clinical Guidelines for Interstitial Cystitis and Bladder Pain Syndrome

The clinical guidelines for interstitial cystitis (IC) and bladder pain syndrome (BPS) have been revised by updating our previous guidelines. The symptoms of IC and BPS, collectively called as hypersensitive bladder (HSB) symptoms, are virtually indistinguishable between IC and BPS; however, IC and BPS should be considered as a separate entity of disorders. We define IC as a bladder disease with Hunner lesions, usually associated with HSB symptoms and bladder inflammation, and BPS as a condition with HSB symptoms in the absence of Hunner lesions and any confusable diseases. Pathophysiology totally differs between IC and BPS. IC involves immunological inflammation probably resulting from autoimmunity, while BPS is associated with the interaction of multiple factors such as neurogenic inflammation, exogenous substances, urothelial defects, psychological stress, and neural hyperactivity. Histopathology also differs between IC and BPS. IC is associated with severe inflammation of the whole bladder accompanied by plasma cell infiltration and urothelial denudation, while BPS shows little pathological changes. Management should begin with a differential diagnosis of IC or BPS, which would require cystoscopy to determine the presence or absence of Hunner lesions. The patients should be treated differently based on the diagnosis following the algorithm, although pain management would be common to IC and BPS. Clinical studies are also to be designed and analyzed separately for IC and BPS.

Antibacterial and therapeutic effects of low energy shock waves on uropathogenic E. coli investigated by in vitro and in vivo cystitis rat model

AIMS

Low-energy shock waves (LESWs) are known to alter cell-membrane permeability. This study aimed to investigate the effect of LESWs on Escherichia coli and E. coli-induced cystitis in rats.

MAIN METHODS

Standardized suspensions of E. coli ATCC25922 were treated with or without LESWs (100 or 300 pulses; 0.12 mJ/mm2; 2 pulses/s) followed by bacterial counting, an antibiotic sensitivity test, and gene ontology analysis and gene-set enrichment analysis. Intravesical administration of saline or E. coli (0.5 mL with 108 CFU/mL) for 30 min was performed in female Sprague-Dawley rats. The rats were treated with or without LESWs (300 pulses; 0.12 mJ/mm2; 2 pulses/s) on days 4 and 5. The changes in inflammatory reactions, uroplakin IIIa staining, and correlation with urodynamic findings were assessed on day 8.

KEY FINDINGS

LESW treatment induced a decrease in CFU and the autoaggregation rate and increased the inhibition zone sizes in a cefazolin-sensitivity study. These changes were associated with gene expression in regulation of cellular membrane components, biofilm formation, and the ATP-binding cassette transporter pathway. E. coli induced bladder hyperactivity and an inflammatory reaction as well as decreased uroplakin IIIa staining; these effects were partially reversed by LESW treatment.

SIGNIFICANCE

The LESW antibacterial effect occurs by altering bacterial cell-membrane gene expression, enhancing antibiotic sensitivity, and inhibiting bladder inflammatory reaction and overactivity. These findings support the potential benefits of LESWs for treatment of recurrent or refractory bacterial cystitis.

Promising Experimental Treatment in Animal Models and Human Studies of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain Syndrome (IC/BPS) remains a mysterious and intricate urological disorder, presenting significant challenges to healthcare providers. Traditional guidelines for IC/BPS follow a hierarchical model based on symptom severity, advocating for conservative interventions as the initial step, followed by oral pharmacotherapy, intravesical treatments, and, in refractory cases, invasive surgical procedures. This approach embraces a multi-tiered strategy. However, the evolving understanding that IC/BPS represents a paroxysmal chronic pain syndrome, often involving extravesical manifestations and different subtypes, calls for a departure from this uniform approach. This review provides insights into recent advancements in experimental strategies in animal models and human studies. The identified therapeutic approaches fall into four categories: (i) anti-inflammation and anti-angiogenesis using monoclonal antibodies or immune modulation, (ii) regenerative medicine, including stem cell therapy, platelet-rich plasma, and low-intensity extracorporeal shock wave therapy, (iii) drug delivery systems leveraging nanotechnology, and (iv) drug delivery systems assisted by energy devices. Future investigations will require a broader range of animal models, studies on human bladder tissues, and well-designed clinical trials to establish the efficacy and safety of these therapeutic interventions.

Stem cell therapy for interstitial cystitis/bladder pain syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic disease with limited treatment options. Current multidisciplinary approach targeting bladder inflammation and urothelial dysfunction has limited durable effect that major surgery is ultimately required for both Hunner and non-Hunner type IC. Various investigational attempts are underway to avoid such operations and preserve the urinary bladder. Stem cell therapy is a fascinating option for treating chronic illnesses. Stem cells can self-renew, restore damaged tissue, and have paracrine effects. The therapeutic efficacy and safety of stem cell therapy have been demonstrated in numerous preclinical models, primarily chemically induced cystitis rat models. Only one clinical trial (phase 1 study) has investigated the safety of human embryonic stem cell-derived mesenchymal stem cells in three Hunner-type IC patients. Under general anesthesia, participants underwent cystoscopic submucosal stem cell injection (2.0 × 107 stem cells/5 mL). No safety issues were reported up to 12 months of follow-up and long-term follow-up (up to 3 years). Although there were variations in therapeutic response, all patients reported significant improvement in pain at 1 month postoperatively. One patient underwent fulguration of the Hunner lesion after the trial, but others reported an overall improvement in pain. The analysis on phase 1/2a trial which had several modifications in protocol is currently ongoing. Despite several limitations that need to be overcome, stem cell therapy could be a potential therapeutic option for treating IC/BPS. Clinical outcome on phase 1/2a trial is important and might provide more insight into the clinical application of stem cell therapy for IC/BPS.

Low-Intensity Extracorporeal Shock Wave Therapy Ameliorates Detrusor Hyperactivity with Impaired Contractility via Transient Potential Vanilloid Channels: A Rat Model for Ovarian Hormone Deficiency

This study explores low-intensity extracorporeal shock wave therapy (LiESWT)'s efficacy in alleviating detrusor hyperactivity with impaired contractility (DHIC) induced by ovarian hormone deficiency (OHD) in ovariectomized rats. The rats were categorized into the following four groups: sham group; OVX group, subjected to bilateral ovariectomy (OVX) for 12 months to induce OHD; OVX + SW4 group, underwent OHD for 12 months followed by 4 weeks of weekly LiESWT; and OVX + SW8 group, underwent OHD for 12 months followed by 8 weeks of weekly LiESWT. Cystometrogram studies and voiding behavior tracing were used to identify the symptoms of DHIC. Muscle strip contractility was evaluated through electrical-field, carbachol, ATP, and KCl stimulations. Western blot and immunofluorescence analyses were performed to assess the expressions of various markers related to bladder dysfunction. The OVX rats exhibited significant bladder deterioration and overactivity, alleviated by LiESWT. LiESWT modified transient receptor potential vanilloid (TRPV) channel expression, regulating calcium concentration and enhancing bladder capacity. It also elevated endoplasmic reticulum (ER) stress proteins, influencing ER-related Ca2+ channels and receptors to modulate detrusor muscle contractility. OHD after 12 months led to neuronal degeneration and reduced TRPV1 and TRPV4 channel activation. LiESWT demonstrated potential in enhancing angiogenic remodeling, neurogenesis, and receptor response, ameliorating DHIC via TRPV channels and cellular signaling in the OHD-induced DHIC rat model.

Effects of low-intensity extracorporeal shock wave therapy on lipopolysaccharide cystitis in a rat model of interstitial cystitis/bladder pain syndrome

PURPOSE

To investigate the effect of low-intensity extracorporeal shock wave therapy (LiESWT) on lipopolysaccharide (LPS)-induced cystitis in an animal model of interstitial cystitis/bladder pain syndrome (IC/BPS).

METHODS

Sprague-Dawley rats were divided into three groups: control, cystitis (LPS group, intravesical injection of LPS (1 mg) twice), and cystitis with LiESWT (LiESWT group). On the third and fourth days, LiESWT was administered (0.12 mJ/mm2, 300 shots each time) on the lower abdomen toward the bladder. On the seventh day, the rats underwent pain assessment and a metabolic cage study. Subsequently, a continuous cystometrogram (CMG) was performed under urethane anaesthesia. Immunohistochemical studies were also performed, including S-100 staining, an immunohistochemical marker of Schwann cells in the bladder.

RESULTS

In the LPS group, the pain threshold in the lower abdomen was significantly lower than that in the control group. In the metabolic cage study, the mean voided volume in the LPS group significantly increased. The CMG also revealed a significant decrease in bladder contraction amplitude, compatible with detrusor underactivity in the LPS group. Immunohistochemical studies showed inflammatory changes in the submucosa, increased fibrosis, and decreased S-100 stain-positive areas in the muscle layer of the LPS group. In the LiESWT group, tactile allodynia and bladder function were ameliorated, and S-100 stain-positive areas were increased.

CONCLUSION

By restoring nerve damage, LiESWT improved lower abdominal pain sensitivity and bladder function in an LPS-induced cystitis rat model. This study suggests that LiESWT may be a new therapeutic modality for IC/BPS.

Multimodal therapies and strategies for the treatment of interstitial cystitis/bladder pain syndrome in Taiwan

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic disease characterized by bladder pain, frequency, and nocturia. The most common pathologies include chronic inflammation and bladder urothelium dysfunction. According to the bladder condition with or without Hunner's lesions, IC/BPS can be divided into "IC" in patients with Hunner's lesion (HIC) and "BPS" in those without Hunner's lesion (NHIC). Previous studies have reported greater central sensitization and interorgan cross-talk in patients with NHIC. Multimodal treatments have been recommended in clinical guidelines under the biopsychosocial model. The bladder-gut-brain axis has also been speculated, and multimodal therapies are necessary. Unfortunately, currently, no treatment has been reported durable for IC/BPS. Patients with IC/BPS usually experience anxiety, depression, holistic physical responses, and even threats to social support systems. The lack of durable treatment outcomes might result from inadequate diagnostic accuracy and differentiation of clinical phenotypes based on the underlying pathophysiology. Precision assessment and treatment are essential for optimal therapy under definite IC/BPS phenotype. This article reviewed currently available literature and proposed a diagnosis and treatment algorithm. Based on bladder therapy combined with suitable physical and psychological therapies, a well-grounded multimodal therapy and treatment algorithm for IC/BPS following a diagnostic protocol are indispensable.

Prospective, Randomized, Double-blind, Placebo-controlled, Pilot Study of Extracorporeal Shock Wave Therapy for Detrusor Underactivity/Underactive Bladder

BACKGROUND

Detrusor underactivity/underactive bladder (DU/UAB) is a disease with great unmet needs and no current approved drug treatment. Extracorporeal shock wave therapy (ESWT) has been shown to improve regeneration of tissue and increase detrusor contractility in preclinical studies of DU/UAB.

OBJECTIVE

To assess ESWT as a treatment of DU/UAB.

DESIGN, SETTING, AND PARTICIPANTS

Patients with DU/UAB were enrolled in this phase 2 randomized, double-blind, placebo-controlled, physician-initiated study.

INTERVENTION

The patients were assigned to ESWT (N = 6, 2500 shocks, frequency of four pulses per second, and maximum total energy flow density of 0.25 mJ/mm2) once a week for 6 wk at the suprapubic bladder area or to placebo (N = 5, shock wave setting without energy transmission).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was the average changes in postvoid residual urine (PVR) from baseline to 4 wk after treatment. Other endpoints included the average changes in 3-d voiding diary, global response assessment of patient satisfaction, Underactive Bladder Questionnaire (UAB-Q) score, and urodynamic evaluation.

RESULTS AND LIMITATIONS

The difference in improvement in PVR was -157.8 ml (95% confidence interval [CI]: -380.1, 64.4) versus -6.6 ml (95% CI: -178.1, 164.9) and -77.5 ml (95% CI: -242.1, 87.1) versus 81.8 ml (95% CI: -137.2, 300.7) for ESWT versus placebo (p = 0.116 and 0.056) at 4 and 12 wk, respectively. The ESWT group exhibited a significant reduction in the UAB-Q score (-4.3; 95% CI: -9.1, 0.4) compared with the placebo group (-0.4; 95% CI: -1.8, 1.0) at 4 wk after treatment (p = 0.025), and the effects were decreased at 12 wk (p = 0.091). This study was limited by small sample size.

CONCLUSIONS

ESWT was well tolerated with a statistically significant decrease of DU/UAB symptoms and a trend to decrease PVR versus placebo. These results indicate that ESWT may be a promising treatment for DU/UAB and multicenter studies are needed.

PATIENT SUMMARY

Bladder shock wave therapy was studied in this randomized, double-blind, placebo-controlled study in patients with inadequate bladder emptying (underactive bladder). Bladder shock wave therapy was found to be well tolerated with an improvement in bladder emptying. These results indicate that bladder shock wave therapy may be a promising treatment for patients who cannot empty their bladder adequately.

Botulinum Toxin Therapy for Bladder Pain Syndrome/Interstitial Cystitis

Purpose of Review

Bladder pain syndrome (BPS)/interstitial cystitis (IC) can also be classified as either non-ulcerative or ulcerative, corresponding to the characteristic cystoscopic findings under hydrodistention. Promising therapeutic effects, including decreased bladder pain, have been reported from recent clinical trials using botulinum toxin A (BoNTA) for the treatment of BPS/IC. This review summarizes the current state of the literature on the underlying mechanisms of BoNTA therapy in BPS/IC as well as new forms of its application.

Recent Findings

BoNTA has its effect in the central nervous system in the afferent nerves as well as in the bladder wall. Besides the well-known effects of BoNTA in the nervous system, pain control as well as reduction of urinary urgency in BPS patients could be achieved by mast cell stabilization effecting histamine release as well as modulation of TRPV and PGE2 pathways, among other systems. In addition, new forms of BoNTA administration have focused on intravesical instillation of the drug in order to circumvent bladder wall injections. Hyperthermia, intravesical hydrogel, and lysosomes have been studied as new ways of BoNTA application in BPS/IC patients. From the available studies, bladder instillation of BoNTA in combination with EMDA is the most promising and effective novel approach.

Summary

The most promising novel application methods for BoNTA in patient with BPS/IC are bladder instillations. Future research needs to point out if bladder instillations with BoNTA with some form of bladder absorption enhancement such as hyperthermia or EMDA would be able to replace BoNTA injections in patients with BPS/IC

Use of low-intensity extracorporeal shock wave therapy in the management of interstitial cystitis/bladder pain syndrome patients: A thirty case study in a tertiary medical center

INTRODUCTION

Low-energy extracorporeal shock wave therapy (LiESWT) is a new potential treatment for intractable interstitial cystitis/bladder pain syndrome (IC/BPS), and this paper will evaluate its therapeutic effects on IC/BPS.

MATERIALS AND METHODS

This prospective clinical trial enrolled 30 women who have been diagnosed with IC/PBS to receive LiESWT treatment at an intensity of 0.25 mJ/mm² and a frequency of 3 pulses/second, for a total of 3000 pulses within 8 weeks. And we assessed questionnaires (including O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI)), 3-day voiding diary, and urodynamic study at the following intervals: 4 weeks of LiESWT (W4), 8 weeks of LiESWT (W8), 1-month follow-up (F1), 3-month follow-up (F3) after LiESWT, and 1 year follow-up (F12).

RESULTS

The primary outcome of questionnaires showed significant improvement of symptoms compared to baseline (W0), especially on ICSI(12.87 ± 3.44 before treatment and 7.87 ± 5.27 at F12, p < 0.05). 3-day voiding diary also revealed significant decrease in daytime voiding frequency (15.57 ± 5.22 times before treatment and 10.70 ± 4.21 times at F1, p < 0.05) and significant increase on average voiding volume (95.85 ± 35.30 mL before treatment and 161.27 ± 74.21 mL at F1, p < 0.05). However, there were no significant differences in all parameters of the urodynamic study.

CONCLUSION

LiESWT can mitigate pain and lower urinary tract symptoms and improve the quality of life in IC/PBS patients, but does not increase the maximal cystometric capacity.

Multimodal Treatment with Cognitive Behavioral Therapeutic Intervention Plus Bladder Treatment Is More Effective than Monotherapy for Patients with Interstitial Cystitis/Bladder Pain Syndrome-A Randomized Clinical Trial

(1) Background: Introduction: Interstitial cystitis/bladder pain syndrome (IC/BPS) not only induces physiological damage but also greatly affects psychological stress. Multidisciplinary therapy has been recommended for IC/BPS treatment, but clinical trial data of combined bladder therapy and cognitive behavioral therapy (CBT) are lacking. This study evaluated CBT efficacy in patients with IC/BPS. (2) Methods: Patients with IC/BPS were randomized to the bladder monotherapy (BT) or combined CBT (CBT) group. The primary endpoint was the self-reported outcome by global response assessment (GRA). Secondary endpoints included IC symptoms and problem index, bladder pain score, Beck’s anxiety inventory (BAI), and depression inventory, and objective parameters were also compared. (3) Result: A total of 30 patients receiving BT and 30 receiving CBT therapy were enrolled. Significant improvement of the BAI at 8 (p = 0.045) and 12 weeks (p = 0.02) post-treatment was observed in the CBT group, with significantly greater GRA scores at 12 weeks (p < 0.001). Repeated measures analysis of variance showed a significant effect within the CBT group on IC/BPS patients’ self-reported treatment outcomes (p = 0.001) and anxiety severity BAI scores (p = 0.033). (4) Conclusion: A multimodal treatment of CBT combined with suitable bladder treatment more effectively improves anxiety severity and treatment outcomes in patients with IC/BPS.

Current Understanding of the Pathophysiology and Novel Treatments of Interstitial Cystitis/Bladder Pain Syndrome

The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) is multifactorial. Identifying the clinical characteristics and cystoscopic findings of bladder-centered IC/BPS facilitates optimal treatment strategies targeting the diseased urinary bladder. Patients with Hunner’s lesion (HIC) and without Hunner’s lesion (NHIC) should be treated differently. Based on the histopathological findings, NHIC can be treated with intravesical instillation of urothelial protective agents, such as hyaluronic acid, to cover the urothelial defects. In non-responders, chronic inflammation and higher urothelial dysfunction can be treated with intravesical botulinum toxin A injection, platelet-rich plasma injection, or low-energy shock wave treatment to reduce inflammation, increase tissue regeneration, and improve the urothelial barrier. Patients with HIC should be treated with electrocauterization first; augmentation enterocystoplasty should only be used in end-stage HIC when the contracted bladder is refractory to other treatments. The antiviral agent, valacyclovir, can be used in patients with HIC, small bladder capacity, and high-grade glomerulations. In addition, behavioral modification is always recommended from the beginning of treatment. Treatment with cognitive behavioral therapy interventions in combination with bladder therapy can reduce anxiety and improve treatment outcomes. Herein, recent advances in the pathophysiology and novel treatments for IC/BPS are reviewed.

The NLRP3 Inflammasome Inhibitor Dapansutrile Attenuates Cyclophosphamide-Induced Interstitial Cystitis

Interstitial cystitis (IC)/bladder pain syndrome (BPS), hereafter referred together as IC, is a clinical syndrome characterized by sterile inflammation in the bladder. While the etiology and pathophysiology of IC remain unclear, it may involve autoimmunity in light of the significant role played by the NLRP3 inflammasome. However, the effect of NLRP3 inhibitors including dapansutrile (Dap) on IC had not been explored previously. Here, we investigated the effect of Dap in the cyclophosphamide (CYP)-induced experimental mouse model of IC, which results in functional and histological alterations confined to the urinary bladder (UB) comparable to that of clinical IC. CYP-induced mice treated with Dap exhibited improved UB pathology and reductions in inflammation scores and the frequency and the number of mast cells and neutrophils, relative to mice that received CYP alone. Dap- and CYP-treated mice also exhibited infiltration of T cells in the spleen and iliac lymph nodes (ILNs) and a concurrent significant decrease (p<0.01) in CXCR3⁺CD8⁺ T cells in the UB, induction of systemic and mucosal dendritic cells (DCs), and reduced levels of systemic proinflammatory cytokines, as compared to CYP alone. We also observed decreases in the expression of several signaling pathways regulators, including interleukin-1 beta (IL-1β), NLRP3, caspase-1, nuclear factor kappa B (NF-κB), and inducible nitric oxide synthase (iNOS) in the UB of CYP- and Dap-treated mice, relative to those receiving CYP alone. Taken together, these results suggest that Dap suppresses IC through the reduction of CXCR3⁺T cells, mast cells, and neutrophils in the UB and induces DCs as a protective measure. The present study identifies the mechanisms underlying the amelioration of IC by the NLRP3 inhibitor Dap and may provide an avenue for a potential therapeutic agent for the treatment of IC.

New Frontiers of Extracorporeal Shock Wave Medicine in Urology from Bench to Clinical Studies

A shock wave (SW), which carries energy and propagates through a medium, is a type of continuous transmitted sonic wave that can achieve rapid energy transformations. SWs have been applied for many fields of medical science in various treatment settings. In urology, high-energy extracorporeal SWs have been used to disintegrate urolithiasis for 30 years. However, at lower energy levels, SWs enhance the expression of vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), proliferating cell nuclear antigen (PCNA), chemoattractant factors, and the recruitment of progenitor cells, and inhibit inflammatory molecules. Low energy extracorporeal shock wave (LESW) therapy has been used in urology for treating chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), interstitial cystitis/bladder pain syndrome (IC/BPS), overactive bladder, stress urinary incontinence, and erectile dysfunction through the mechanisms of anti-inflammation, neovascularization, and tissue regeneration. Additionally, LESW have been proven to temporarily increase tissue permeability and facilitate intravesical botulinum toxin delivery for treating overactive bladders in animal studies and in a human clinical trial. LESW assisted drug delivery was also suggested to have a synergistic effect in combination with cisplatin to improve the anti-cancer effect for treating urothelial cancer in an in vitro and in vivo study. LESW assisted drug delivery in uro-oncology is an interesting suggestion, but no comprehensive clinical trials have been conducted as of yet. Taken together, LESW is a promising method for the treatment of various diseases in urology. However, further investigation with a large scale of clinical studies is necessary to confirm the real role of LESW in clinical use. This article provides information on the basics of SW physics, mechanisms of action on biological systems, and new frontiers of SW medicine in urology.

Use of the Shock Wave Therapy in Basic Research and Clinical Applications-From Bench to Bedsite

Shock Waves (SW) are acoustic disturbances that propagate through a medium carrying the energy. These specific sonic pulses are composed of two phases—high positive pressure, a rise time < 10 ns, and a tensile wave. Originally Shock Waves were introduced to clinical practice as a part of the lithotripsy therapy focused on disrupting calcific deposits in the body. Since that time, shock wave therapy (SWT) has gone far beyond the original application related to the destruction of kidney stones. In this narrative Review, we present basic clinical applications of the SWT along with the potential therapeutic application in clinical practice.

Low-Energy Shock Wave Plus Intravesical Instillation of Botulinum Toxin A for Interstitial Cystitis/Bladder Pain Syndrome: Pathophysiology and Preliminary Result of a Novel Minimally Invasive Treatment

Low-energy shock wave (LESW) therapy is known to facilitate tissue regeneration with analgesic and anti-inflammatory effects. LESW treatment has been demonstrated to be effective in treating chronic prostatitis and pelvic pain syndrome as well as overactive bladder, and it has a potential effect on interstitial cystitis/bladder pain syndrome (IC/BPS) in humans. LESW reduces pain behavior, downregulates nerve growth factor expression, and suppresses bladder overactivity by decreasing the expression of inflammatory proteins. Previous rat IC models have shown that LESW can increase urothelial permeability, facilitate intravesical delivery of botulinum toxin A (BoNT-A), and block acetic acid-induced hyperactive bladder, suggesting that LESW might be a potential therapeutic module for relieving bladder inflammatory conditions, such as bladder oversensitivity, IC/BPS, and overactive bladder. A recent clinical trial showed that LESW monotherapy was associated with a significant reduction in pain scores and IC symptoms. BoNT-A detrusor injection or liposome-encapsulated BoNT-A instillation could also inhibit inflammation and improve IC symptoms. However, BoNT-A injection requires anesthesia and certain complications might occur. Our preliminary study using LESW plus intravesical BoNT-A instillation every week demonstrated an improvement in global response assessment without any adverse events. Moreover, an immunohistochemistry study revealed the presence of cleaved SNAP25 protein in the suburothelium of IC bladder tissue, indicating that BoNT-A could penetrate across the urothelial barrier after application of LESW. These results provide evidence for the efficacy and safety of this novel IC/BPS treatment by LESW plus BoNT-A instillation, without anesthesia, and no bladder injection. This article reviews the current evidence on LESW and LESW plus intravesical therapeutic agents on bladder disorders and the pathophysiology and pharmacological mechanism of this novel, minimally invasive treatment model for IC/BPS.

An indirect comparison meta-analysis of noninvasive intravesical instillation and intravesical injection of botulinum toxin-A in bladder disorders

BACKGROUND

Botulinum toxin type A (BTX-A) intravesical instillation and BTX-A intravesical injection are both effective treatments or overactive bladder (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS), but direct comparative studies of the two treatments are lacking.

METHODS

We conducted a pairs-comparison meta-analysis and an adjusted indirect comparison meta-analysis extracting published data from randomized controlled trials in literature databases from the inception of each database to Aug. 31, 2021, evaluating efficacy and safety of BTX-A intravesical instillation and BTX-A intravesical injection. We also carried out a subgroup analysis.

RESULTS

We identified 24 trials in 21 studies were included in our study, of which 18 trials in 17 studies were BTX-A intravesical injections, 6 trials in 4 studies were BTX-A intravesical instillation. Compared with the normal saline injection, BTX-A intravesical injections for patients with OAB and IC/ BPS can obviously improve the symptoms of urinary frequency, urgency episode, UI and UUI, but BTX-A significantly increased the rate of urinary retention and urinary tract infection and increased PVR (p < 0.05). Adjusted indirect comparison meta-analysis showed that BTX-A intravesical injections was more effective than BTX-A intravesical instillation (p > 0.05). Surprisingly, BTX-A intravesical instillation had fewer side effects than BTX-A intravesical injections (p < 0.05).

CONCLUSIONS

Although BTX-A intravesical injections of OAB and IC/BPS has been significantly superior the BTX-A intravesical instillation, it has major side effects, but this needs to be confirmed by more large-scale, multicenter, direct comparison randomized controlled trials.

Urinary Biomarkers in Interstitial Cystitis/Bladder Pain Syndrome and Its Impact on Therapeutic Outcome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is defined as a chronic bladder disorder with suprapubic pain (pelvic pain) and pressure and/or discomfort related to bladder filling accompanied by lower urinary tract symptoms, such as urinary frequency and urgency without urinary tract infection (UTI) lasting for at least 6 weeks. IC/BPS presents significant bladder pain and frequency urgency symptoms with unknown etiology, and it is without a widely accepted standard in diagnosis. Patients’ pathological features through cystoscopy and histologic features of bladder biopsy determine the presence or absence of Hunner lesions. IC/PBS is categorized into Hunner (ulcerative) type IC/BPS (HIC/BPS) or non-Hunner (nonulcerative) type IC/BPS (NHIC/BPS). The pathophysiology of IC/BPS is composed of multiple possible factors, such as chronic inflammation, autoimmune disorders, neurogenic hyperactivity, urothelial defects, abnormal angiogenesis, oxidative stress, and exogenous urine substances, which play a crucial role in the pathophysiology of IC/BPS. Abnormal expressions of several urine and serum specimens, including growth factor, methylhistamine, glycoprotein, chemokine and cytokines, might be useful as biomarkers for IC/BPS diagnosis. Further studies to identify the key molecules in IC/BPS will help to improve the efficacy of treatment and identify biomarkers of the disease. In this review, we discuss the potential medical therapy and assessment of therapeutic outcome with urinary biomarkers for IC/BPS.

Low-Intensity Extracorporeal Shock Wave Therapy Promotes Bladder Regeneration and Improves Overactive Bladder Induced by Ovarian Hormone Deficiency from Rat Animal Model to Human Clinical Trial

Postmenopausal women with ovary hormone deficiency (OHD) are subject to overactive bladder (OAB) symptoms. The present study attempted to elucidate whether low-intensity extracorporeal shock wave therapy (LiESWT) alters bladder angiogenesis, decreases inflammatory response, and ameliorates bladder hyperactivity to influence bladder function in OHD-induced OAB in human clinical trial and rat model. The ovariectomized (OVX) for 12 months Sprague–Dawley rat model mimicking the physiological condition of menopause was utilized to induce OAB and assess the potential therapeutic mechanism of LiESWT (0.12 mJ/mm², 300 pulses, and 3 pulses/second). The randomized, single-blinded clinical trial was enrolled 58 participants to investigate the therapeutic efficacy of LiESWT (0.25 mJ/mm², 3000 pulses, 3 pulses/second) on postmenopausal women with OAB. The results revealed that 8 weeks’ LiESWT inhibited interstitial fibrosis, promoted cell proliferation, enhanced angiogenesis protein expression, and elevated the protein phosphorylation of ErK1/2, P38, and Akt, leading to decreased urinary frequency, nocturia, urgency, urgency incontinence, and post-voided residual urine volume, but increased voided urine volume and the maximal flow rate of postmenopausal participants. In conclusion, LiESWT attenuated inflammatory responses, increased angiogenesis, and promoted proliferation and differentiation, thereby improved OAB symptoms, thereafter promoting social activity and the quality of life of postmenopausal participants.

A Systematic Review of Therapeutic Approaches Used in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic bladder disorder with limited therapeutic options currently available. The present review provides an extensive overview of therapeutic approaches used in in vitro, ex vivo, and in vivo experimental models of IC/BPS. Publications were identified by electronic search of three online databases. Data were extracted for study design, type of treatment, main findings, and outcome, as well as for methodological quality and the reporting of measures to avoid bias. A total of 100 full-text articles were included. The majority of identified articles evaluated therapeutic agents currently recommended to treat IC/BPS by the American Urological Association guidelines (21%) and therapeutic agents currently approved to treat other diseases (11%). More recently published articles assessed therapeutic approaches using stem cells (11%) and plant-derived agents (10%), while novel potential drug targets identified were proteinase-activated (6%) and purinergic (4%) receptors, transient receptor potential channels (3%), microRNAs (2%), and activation of the cannabinoid system (7%). Our results show that the reported methodological quality of animal studies could be substantially improved, and measures to avoid bias should be more consistently reported in order to increase the value of preclinical research in IC/BPS for potential translation to a clinical setting.

Low Energy Shock Wave Therapy Attenuates Mitochondrial Dysfunction and Improves Bladder Function in HCl induced Cystitis in Rats

BACKGROUND

We examine the effects of low energy shock wave (LESW)) on bladder and mitochondrial function in a rat model of HCl induced cystitis, and the influence of dynamic bladder filling volume on LESW responses. Dysregulation of mitochondria function may impact the urothelial barrier and contribute to bladder dysfunction in patients with Interstitial cystitis/bladder pain syndrome (IC/BPS).

MATERIALS AND METHODS

Female Sprague-Dawley rats underwent urethral catheterization and intravesical instillation of 0.2 ml of 0.4N HCl (N=32) or 0.2 ml saline (N=8) kept for 90 s. After HCl instillation, the bladder received LESW treatment while filled with 0 ml, 0.2 ml or 0.4 ml saline or no LESW treatment. Continuous cystometry (CMG) was performed on day 8. The bladder was harvested after CMG for histology and Western blotting.

RESULTS

HCl provoked bladder overactivity, bladder wall inflammation marked by infiltration of mast cells, increased bax/bcl2 ratio consistent with increased TUNEL staining and increased release of mitochondrial-integrity markers (cleaved caspase 3 and Cytochrome c). LESW treatment suppressed HCl provoked bladder overactivity in association with lower inflammatory reaction, mast cells infiltration, and a lower bax/bcl2 ratio also reflected by reduced TUNEL staining and mitochondrial-integrity markers irrespective of the volume of saline in bladder at the time of LESW.

CONCLUSIONS

These findings support that antiinflammatory effect of LESW in chemical cystitis is associated with the reversal of the molecular-cellular perturbations in mitochondrial dependent intrinsic apoptotic pathway.

Extracorporeal Shockwave Therapy in the Treatment of Trigger Finger: A Randomized Controlled Study

OBJECTIVES

To determine the efficacy of extracorporeal shockwave therapy (ESWT) and to determine the ideal energy flux density of wide-focused ESWT in the treatment of trigger finger (TF).

DESIGN

Double-blind randomized controlled trial.

SETTING

A university hospital.

PARTICIPANTS

A total of 60 patients (N=60) with grade II TF according to the Quinnell classification were randomly and evenly allocated to 3 treatment groups.

INTERVENTIONS

Three treatment groups included a high-energy ESWT (HS) group (energy flux density of 0.01 mJ/mm², 5.8 bar, 1500 impulses, once per week for 4wk), a low-energy ESWT (LS) group (energy flux density of 0.006 mJ/mm², 3 bar, 1500 impulses, once per week for 4wk), and a sham intervention group (sham group). All participants received 6 months of follow-up after intervention when only painkillers were allowed as concomitant treatment.

MAIN OUTCOME MEASURES

Clinical outcomes were followed at baseline and 1, 3, and 6 months after intervention, including pain score, frequency of triggering, severity of triggering, functional impact of triggering, and quick Disabilities of the Arm, Shoulder, and Hand questionnaire (qDASH).

RESULTS

All groups showed significant improvements from baseline in all clinical parameters, except for functional impact of triggering, 6 months after the interventions. However, the HS group demonstrated a higher magnitude of improvement than the LS and sham groups. In addition, the HS group reported significantly lower pain (P=.01) and lower qDASH (P=.008) than the sham group 6 months after the interventions. No adverse effects were reported in the HS and LS groups within 6 months of follow-up.

CONCLUSIONS

Wide-focused ESWT is a safe and effective but dose-dependent alternative facilitating pain relief and functional improvement in the treatment of grade II TF according to the Quinnell classification.

Novel Applications of Non-Invasive Intravesical Botulinum Toxin a Delivery in the Treatment of Functional Bladder Disorders

Although intravesical botulinum toxin type A (BoNT-A) injection for functional bladder disorders is effective, the injection-related problems-such as bladder pain and urinary tract infection-make the procedure invasive and inconvenient. Several vehicles have recently been developed to deliver BoNT-A without injection, thereby making the treatment less or non-invasive. Laboratory evidence revealed that liposome can carry BoNT-A across the uroepithelium and act on sub-urothelial nerve endings. A randomized placebo controlled study revealed that intravesical administration of liposome-encapsulated BoNT-A and TC-3 hydrogel embedded BoNT-A can improve urinary frequency, urgency, and reduce incontinence in patients with overactive bladders. A single-arm prospective study also revealed that intravesical administration of TC-3 hydrogel embedded BoNT-A can relieve bladder pain in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). We recently administered suprapubic energy shock wave (ESW) after BoNT-A intravesical administration in six patients with IC/BPS. Although pain reduction and symptom improvement were not significant, immunochemical staining showed cleaved synaptosome-associated protein 25 in the bladder after the procedure. This suggests that ESW can promote passage of BoNT-A across the uroepithelium. In conclusion, using vehicles to intra-vesically deliver BoNT-A for functional bladder disorders is promising. Further studies are necessary to confirm the efficacy and explore novel applications.

The Effect of Low-intensity Shockwave Therapy on Non-neurogenic Lower Urinary Tract Symptoms: A Systematic Review and Meta-analysis of Preclinical and Clinical Studies

CONTEXT

Low-intensity shockwave therapy (LiST) has emerged as an effective treatment for pain in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and it has been postulated that LiST may also be effective in patients with lower urinary tract symptoms (LUTS).

OBJECTIVE

To perform a systematic review and meta-analysis of experimental and clinical studies exploring the effect of LiST on LUTS in an attempt to provide clinical implications for future research.

EVIDENCE ACQUISITION

We systematically searched PubMed, Cochrane Library, and Scopus databases from inception to March 2021 for relevant studies. We provided a qualitative synthesis regarding the role of LiST in LUTS and performed a single-arm, random-effect meta-analysis to assess the absolute effect of LiST on LUTS only in patients with CP/CPPS (PROSPERO: CRD42021238281).

EVIDENCE SYNTHESIS

We included 23 studies (11 experimental studies, seven nonrandomized controlled trials [non-RCTs], and five RCTs) in the systematic review and seven in the meta-analysis. All experimental studies were performed on rats with LUTS, and the clinical studies recruited a total of 539 participants. In patients with CP/CPPS, the absolute effect of LiST on maximum flow rate and postvoid residual was clinically insignificant. However, the available studies suggest that LiST is effective for the management of pain in patients with either CP/CPPS or interstitial cystitis/bladder pain syndrome. Additionally, LiST after intravesical instillation of botulinum neurotoxin type A may enhance its absorption and substitute botulinum neurotoxin type A injections in patients with overactive bladder. Furthermore, the available evidence is inconclusive about the role of LiST in patients with benign prostatic obstruction, stress urinary incontinence, or underactive bladder/detrusor hypoactivity.

CONCLUSIONS

LiST may be effective for some disorders causing LUTS. Still, further studies on the matter are necessary, since the available evidence is scarce.

PATIENT SUMMARY

Low-intensity shockwave therapy represents a safe, easily applied, indolent, and repeatable on an outpatient basis treatment modality that may improve lower urinary tract symptoms.

Improves symptoms and urinary biomarkers in refractory interstitial cystitis/bladder pain syndrome patients randomized to extracorporeal shock wave therapy versus placebo

Extracorporeal shock wave therapy (ESWT) has been shown to improve symptoms in patients with interstitial cystitis/bladder pain syndrome (IC/BPS); however, there is a lack of objective evidence. We measured change of urinary biomarker levels in 25 patients with IC/BPS received ESWT or placebo once a week for 4 weeks. Urines were collected from participants at baseline, 4 and 12 weeks post treatment. A representative 41 inflammatory growth factors, cytokines, and chemokines in urine were measured using a MILLIPLEX immunoassay kit. Symptom bother was assessed by O’Leary-Sant symptom scores (OSS), and visual analog scale (VAS) for pain. The ESWT group exhibited a significant reduction in the OSS and VAS compared to the placebo group 4 weeks post-treatment (P < 0.05), and the effects were persistent at 12 weeks. The difference in urinary markers change in ESWT versus placebo was P = 0.054 for IL4, P = 0.013 for VEGF, and P = 0.039 for IL9 at 4 weeks. The change of urine biomarker was not significant in other biomarkers or all the measured proteins at 12 weeks. The current data suggest that IL4, IL9, and VEGF mediation may be involved in its pathophysiologic mechanisms and response to LESW treatment.

New Frontiers or the Treatment of Interstitial Cystitis/Bladder Pain Syndrome - Focused on Stem Cells, Platelet-Rich Plasma, and Low-Energy Shock Wave

Interstitial cystitis/bladder pain syndrome (IC/BPS), which is characterized by bladder pain and irritative voiding symptoms, is a frustrating disease without effective treatment. The cause is still largely not understood, although urothelium ischemia/hypoxia, apoptosis, denudation, and infiltration of inflammatory cells are common histopathological findings. The current uncertainty regarding the etiology and pathology of IC/BPS has a negative impact on its timely and successful treatment; therefore, the development of new treatment modalities is urgently needed. Herein, we present advances in our knowledge on this topic and review the potential application of regenerative medicine for the treatment of IC/BPS. This article provides information on the basic characteristics and clinical evidence of stem cells, platelet-rich plasma (PRP), and low-energy shock waves (LESWs) based on a literature review with a search strategy for articles related to IC/BPS, stem cells, PRP, and LESW published in MEDLINE and PubMed. Stem cells, PRP, and LESW, which modulate inflammatory processes and promote tissue repair, have been proven to improve bladder regeneration, relieve bladder pain, inhibit bladder inflammation, and increase bladder capacity in some preclinical studies. However, clinical studies are still in their infancy. Based on the mechanisms of action of stem cells, PRP, and LESW documented in many preclinical studies, the potential applications of regenerative medicine for the treatment of IC/BPS is an emerging frontier of interest. However, solid evidence from clinical studies remains to be obtained.

Treatment of Interstitial Cystitis/Bladder Pain Syndrome: A Contemporary Review

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating condition affecting approximately 3% of the female population. IC/BPS is defined as an unpleasant sensation (pain, pressure, discomfort) perceived to be related to the urinary bladder, associated with lower urinary tract symptoms for more than six weeks duration, in the absence of infection or other identifiable cause. This condition is known to have a profound negative impact on quality of life. There are few well-studied treatment options and no cure for this condition, which is therefore challenging to treat. The purpose of this narrative review is to summarise the contemporary literature, including the Canadian Urological Association (CUA) and American Urological Association (AUA) guidelines, on various treatment options that exist for IC/BPS, including conservative therapies, oral therapies, intravesical therapies, and more invasive surgical options. Most importantly, this review highlights the need for an individualised, multimodal approach to the treatment of IC/BPS.

Clinical Management of Bladder Pain Syndrome/Interstitial Cystitis: A Review on Current Recommendations and Emerging Treatment Options

Bladder pain syndrome (BPS) is a chronic condition characterized by pelvic pain or pressure which is perceived to be originating from the bladder, accompanied by one or more urinary symptoms, including frequency, urgency and nocturia. The precise etiology of BPS is not fully understood. Chronic bacterial infection, defective glycosaminoglycan (GAG) layer of the bladder urothelium, inappropriate activation of mast cells in the suburothelial layer of the bladder, autoimmune-mediated mechanisms and autonomic nervous system dysfunction have all been implicated. Treatments targeted at each of these mechanisms have been developed with mixed outcomes. High-quality research into the treatment options is lacking and it is difficult to draw definite conclusions. The treatment approach is multimodal and should be patient specific, targeting the symptoms which they find most bothersome. Conservative treatment, including patient education, behavioural modification, dietary advice, stress relief and physical therapy is an essential initial management strategy for all patients. If no response is observed, oral treatments such as amitriptyline are likely to offer the greatest response. Cystoscopy is essential to phenotype patients, and Hunner lesion directed therapy with fulguration or resection can be performed at the same time. Intravesical instillation of DMSO or lidocaine, detrusor injections of botulinum toxin A and neuromodulation can be used if initial management fails to improve symptoms. Oral cyclosporin can be trialled in those experienced with its use; however, it is associated with significant adverse events and requires intense monitoring. Lastly, radical surgery should be reserved for those with severe, unremitting BPS, in which quality of life is severely affected and not improved by previously mentioned interventions. Future work investigating exact aetiological factors will help target the development of efficacious treatment options, and several promising oral and intravesical treatments are emerging.