Interstitial cystitis pathogenesis and treatment

[Bladder pain syndrome: Long-term results (15 years) of a single-center experience]

INTRODUCTION

The management of bladder pain syndrome (BPS) in our center is standardized although there is no real consensus and recommendations. The objectives of our study were to assess the effectiveness of the treatment offered and to identify predictive factors of response to treatment.

PATIENTS AND METHODS

Single-center retrospective study including all patients with BPS. Patient and outcome measures included ICSI and ICPI scores, daytime voiding interval (DVI), nocturnal pollakiuria (NPK), and subjective satisfaction (SS). The complete care protocol (CCP) was based on a hydrodistension test followed by a cimetidine treatment then by 6 instillations of dimethyl sulfoxide followed by a maintenance treatment with pentosan polysulfate. The main objective of our study was the patient's SS at 3months and at medium term. One of the secondary objectives was to study the predictive factors of response to treatment.

OUTCOMES

From 2002 to 2019, 211 patients (90.5% women) were treated for BPS. Sixty-nine patients (35%) underwent the CCP that provided significant improvement in ICSI, ICPI, DVI and NPK and SS of 52.2%.). In the medium term, 149 patients were reassessed with a median follow-up of 99.6months (±3.6): 71.8% were satisfied and 54.2% were no longer receiving treatment. Among the 49 patients who initially received PSC, 74% were satisfied at 89.8 months of median follow-up (±2.9). In multivariate analysis, patients with a pain perception disorder (HR=0.17 IC95=0.05-0.52; P=0.002) or consuming anxiolytics (HR=0.3; IC95=0.13-0.69; P=0.004) had a statistically greater risk of not being satisfied.

CONCLUSION

In our study, the CCP achieves subjective medium-term satisfaction in nearly 75% of patients with BPS. These data deserve to be confirmed on a larger scale in a prospective protocol.

LEVEL OF EVIDENCE: 4

Use of botulinum toxin for voiding dysfunction

The use of botulinum toxin A (BoNT-A) has expanded across a range of lower urinary tract conditions. This review provides an overview of the current indications for BoNT-A in the lower urinary tract and critically evaluates the published evidence within each area. The classic application of BoNT-A has been in the management of refractory neurogenic detrusor overactivity (NDO) and overactive bladder (OAB). There is a large volume of high-quality evidence, including numerous randomized placebo-controlled trials, which demonstrate the efficacy of BoNT-A over a long follow-up period. The culmination of this robust evidence-base has led to onabotulinumtoxin A (onaBoNT-A) receiving regulatory approval as a second-line treatment for NDO at a dose of 200 U and OAB at dose of 100 U. Other applications for BoNT-A are used on an off-license basis and include interstitial cystitis/bladder pain syndrome (IC/BPS), benign prostatic hyperplasia (BPH), and detrusor sphincter dyssynergia (DSD). These applications are associated with a less mature evidence-base although the literature is rapidly evolving. At present, the results for painful bladder syndrome (PBS) are promising and BoNT-A injections are recommended as a fourth line option in recent international guidelines, although larger randomized study with longer follow-up are required to confirm the initial findings. As a treatment for DSD, BoNT-A injections have shown potential but only in a small number of trials of limited quality. No definite recommendation can be made based on the current evidence. Finally, the results for the treatment of BPH have been variable and recent high quality randomized controlled trials (RCTs) have suggested no benefit over placebo so at present it cannot be recommended for routine clinical practice. Future advances of BoNT-A include liposome encapsulated formulations which are being developed as an alternative to intravesical injections.

Botulinum Toxin A for Bladder Pain Syndrome/Interstitial Cystitis

Botulinum neurotoxin A (BoNT-A), derived from Clostridium botulinum, has been used clinically for several diseases or syndrome including chronic migraine, spasticity, focal dystonia and other neuropathic pain. Chronic pelvic or bladder pain is the one of the core symptoms of bladder pain syndrome/interstitial cystitis (BPS/IC). However, in the field of urology, chronic bladder or pelvic pain is often difficult to eradicate by oral medications or bladder instillation therapy. We are looking for new treatment modality to improve bladder pain or associated urinary symptoms such as frequency and urgency for patients with BPS/IC. Recent studies investigating the mechanism of the antinociceptive effects of BoNT A suggest that it can inhibit the release of peripheral neurotransmitters and inflammatory mediators from sensory nerves. In this review, we will examine the evidence supporting the use of BoNTs in bladder pain from basic science models and review the clinical studies on therapeutic applications of BoNT for BPS/IC.

Hydrodistension plus Onabotulinumtoxin A in bladder pain syndrome refractory to conservative treatments

INTRODUCTION

For bladder pain syndrome (BPS) refractory to conservative treatment, the European guidelines consider bladder hydrodistention (HD) under anaesthesia and the injection of Onabotulinumtoxin A (OnabotA) jointly. The objective of this study was to assess our experience in implementing this technique.

MATERIAL AND METHODS

A prospective study of 25 patients with BPS who underwent HD plus a submucosal injection of 100 U of OnabotA in trigone. The Hunner lesions were treated endoscopically using resection or electrocoagulation. Thirty-eight procedures were performed (25 first interventions and 13 reoperations). To study the clinical change, we evaluated the subjective improvement (Treatment Benefit Scale [TBS] and Patient Global Impression of Change [PGIC] scales), the visual analogue scale (VAS) for pain, the Bladder Pain/Interstitial Cystitis Symptom Score (BPIC-SS) questionnaire and the voiding diary for 3 days. For the data analysis, we employed the Wilcoxon, Kruskal-Wallis, Kaplan-Meier and log-rank tests.

RESULTS

We observed subjective improvement in 21 patients (84%), which was significant in 47% of these patients, moderate in 41.2% and slight in 11.8%. Four patients did not improve. A post-treatment reduction in the pain VAS (from 7.1 to 1.8 points; P=.001), in daytime (from 11.8 to 7.5; P=.012) and night-time (from 5.9 to 3.6; P=.003) voiding frequency and in the BPIC-SS (from 27.9 to 11.2 points; P=.042). The degree of improvement was not related to age, the presence of bladder lesions or the treatment of relapses. The median duration of improvement was 7 months (95% CI 5.69-8.31), although this duration was somewhat longer for the patients younger than 65 years. Mild complications occurred in 23.7% of the cases.

CONCLUSIONS

The joint implementation of HD plus OnabotA is a valid therapeutic option in refractory BPS, which provides good clinical results and maintains its effectiveness in retreatments.

Polymorphism in the SCN9A voltage-gated sodium channel gene associated with interstitial cystitis/bladder pain syndrome

OBJECTIVE

To determine whether an association exists between interstitial cystitis/bladder pain syndrome (IC/BPS) and a nonsynonymous single nucleotide polymorphism in the SCN9A voltage-gated sodium channel gene previously associated with other chronic pain syndromes.

MATERIALS AND METHODS

Germline deoxyribonucleic acid was sampled from archived bladder biopsy specimens from patients with a documented diagnosis of IC/BPS. Deoxyribonucleic acid from hysterectomy specimens was obtained as a control population. The genotype of single nucleotide polymorphism rs6746030 was determined by deoxyribonucleic acid sequencing after polymerase chain reaction amplification. Contingency analysis of genotypes was performed using Pearson's chi-square test and Fisher's exact test.

RESULTS

Polymerase chain reaction product was obtained from 26 of 31 control specimens and from 53 of 57 IC/BPS biopsy specimens. Of the 26 control subjects, 3 (11.5%) were genotype AG and 23 were GG. In contrast, AA or AG genotypes were present in 21 of 53 (39.6%) patients with IC/BPS, a statistically significant difference compared with the controls (Pearson's chi-square, P=.036). Similarly, the A allele was at a greater frequency in the IC/BPS group using Fisher's exact test (P=.009).

CONCLUSION

These data strongly suggest that pain perception in at least a subset of patients with IC/BPS is influenced by this polymorphism in the SCN9A voltage-gated sodium channel.

Association of bladder pain syndrome/interstitial cystitis with urinary calculus: a nationwide population-based study

INTRODUCTION AND HYPOTHESIS

Although one prior study reported an association between bladder pain syndrome/interstitial cystitis (BPS/IC) and urinary calculi (UC), no population-based study to date has been conducted to explore this relationship. Therefore, using a population-based data set in Taiwan, this study set out to investigate the association between BPS/IC and a prior diagnosis of UC.

METHODS

This study included 9,269 cases who had received their first-time diagnosis of BPS/IC between 2006 and 2007 and 46,345 randomly selected controls. We used conditional logistic regression analysis to compute the odds ratio (OR) and its corresponding 95 % confidence interval (CI) for having been previously diagnosed with UC between cases and controls.

RESULTS

There was a significant difference in the prevalence of prior UC between cases and controls (8.1 vs 4.3 %, p < 0.001). Conditional logistic regression analysis revealed that cases were more likely to have been previously diagnosed with UC than controls (OR = 1.70; 95 % CI = 1.56-1.84) after adjusting for chronic pelvic pain, irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, depression, panic disorder, migraine, sicca syndrome, allergy, endometriosis, and asthma. BPS/IC was found to be significantly associated with prior UC regardless of stone location; the adjusted ORs of kidney calculus, ureter calculus, bladder calculus, and unspecified calculus when compared to controls were 1.58 (95 % CI = 1.38-1.81), 1.73 (95 % CI = 1.45-2.05), 3.80 (95 % CI = 2.18-6.62), and 1.83 (95 % CI = 1.59-2.11), respectively.

CONCLUSIONS

This work generates the hypothesis that UC may be associated with BPS/IC.

YKL-40 and mast cells are associated with detrusor fibrosis in patients diagnosed with bladder pain syndrome/interstitial cystitis according to the 2008 criteria of the European Society for the Study of Interstitial Cystitis

AIMS

Bladder pain syndrome/interstitial cystitis (BPS/IC), diagnosed according to the new 2008 criteria of the European Society for the Study of Interstitial Cystitis (ESSIC), may lead to detrusor fibrosis. In some inflammatory diseases, fibrosis is related to YKL-40. The aims were to examine YKL-40 antigenic expression in bladder tissue and levels in serum and urine in BPS/IC and to evaluate whether YKL-40 could be a non-invasive, prognostic biomarker for bladder fibrogenesis and treatment intensity.

METHODS AND RESULTS

Immunohistochemistry, immunoelectron microscopy and enzyme-linked immunosorbent assay (ELISA) analyses in 45 patients showed YKL-40 expression in detrusor mast cell granules and submucosal macrophages, and elevated YKL-40 levels in serum and urine compared to healthy individuals (median 72 versus 7 μg/l, P < 0.001). Clinicopathological parameters showed associations of detrusor fibrosis with YKL-40-positive cells (P = 0.001), mast cells (P = 0.014) and urine YKL-40 (P = 0.009). Bladder capacity correlated inversely with YKL-40-positive cells (P < 0.001) and mast cells (P = 0.029). Treatment intensity was not associated with YKL-40.

CONCLUSION

Serum and urine levels of YKL-40 may be used as non-invasive biomarkers in BPS/IC for the evaluation of bladder fibrogenesis.

Gene expression profile of bladder tissue of patients with ulcerative interstitial cystitis

Background

Interstitial cystitis (IC), a chronic bladder disease with an increasing incidence, is diagnosed using subjective symptoms in combination with cystoscopic and histological evidence. By cystoscopic examination, IC can be classified into an ulcerative and a non-ulcerative subtype. To better understand this debilitating disease on a molecular level, a comparative gene expression profile of bladder biopsies from patients with ulcerative IC and control patients has been performed.

Results

Gene expression profiles from bladder biopsies of five patients with ulcerative IC and six control patients were generated using Affymetrix GeneChip expression arrays (Affymetrix – GeneChip^® Human Genome U133 Plus 2.0). More than 31,000 of > 54,000 tested probe sets were present (detection p-value < 0.05). The difference between the two groups was significant for over 3,500 signals (t-test p-value < 0.01), and approximately 2,000 of the signals (corresponding to approximately 1,000 genes) showed an IC-to-healthy expression ratio greater than two. The IC pattern had similarities to patterns from immune system, lymphatic, and autoimmune diseases. The dominant biological processes were the immune and inflammatory responses. Many of the up-regulated genes were expressed in leukocytes, suggesting that leukocyte invasion into the bladder wall is a dominant feature of ulcerative IC. Histopathological data supported these findings.

Conclusion

GeneChip expression arrays present a global picture of ulcerative IC and provide us with a series of marker genes characteristic for this subtype of the disease. Evaluation of biopsies from other bladder patients with similar symptoms (e.g. patients with non-ulcerative IC) will further indicate whether the data presented here will be valuable for the diagnosis of IC.

Bladder hyperactivity and increased excitability of bladder afferent neurons associated with reduced expression of Kv1.4 alpha-subunit in rats with cystitis

Hyperexcitability of C-fiber bladder afferent pathways has been proposed to contribute to urinary frequency and bladder pain in chronic bladder inflammation including interstitial cystitis. However, the detailed mechanisms inducing afferent hyperexcitability after bladder inflammation are not fully understood. Thus, we investigated changes in the properties of bladder afferent neurons in rats with bladder inflammation induced by intravesical application of hydrochloric acid. Eight days after the treatment, bladder function and bladder sensation were analyzed using cystometry and an electrodiagnostic device of sensory function (Neurometer), respectively. Whole cell patch-clamp recordings and immunohistochemical staining were also performed in dissociated bladder afferent neurons identified by a retrograde tracing dye, Fast Blue, injected into the bladder wall. Cystitis rats showed urinary frequency that was inhibited by pretreatment with capsaicin and bladder hyperalgesia mediated by C-fibers. Capsaicin-sensitive bladder afferent neurons from sham rats exhibited high thresholds for spike activation and a phasic firing pattern, whereas those from cystitis rats showed lower thresholds for spike activation and a tonic firing pattern. Transient A-type K(+) current density in capsaicin-sensitive bladder afferent neurons was significantly smaller in cystitis rats than in sham rats, although sustained delayed-rectifier K(+) current density was not altered after cystitis. The expression of voltage-gated K(+) Kv1.4 alpha-subunits, which can form A-type K(+) channels, was reduced in bladder afferent neurons from cystitis rats. These data suggest that bladder inflammation increases bladder afferent neuron excitability by decreasing expression of Kv1.4 alpha-subunits. Similar changes in capsaicin-sensitive C-fiber afferent terminals may contribute to bladder hyperactivity and hyperalgesia due to acid-induced bladder inflammation.

Bacterial cystitis is accompanied by increased peripheral thermal sensitivity in mice

PURPOSE

Visceral inflammation and pain associated with chemical cystitis produce increased sensitivity to noxious stimuli in the sacral dermatomes. We determined whether a similar sensitization occurs in response to bacterial cystitis.

MATERIALS AND METHODS

Bacterial cystitis was induced by intravesical instillation of Escherichia coli 1677 in female C57BL/6N and C3H/OuJ mice (Jackson Laboratories, Bar Harbor, Maine). C3H/HeJ mice (Jackson Laboratories) served as a control because C3H/HeJ mice lack functional toll-like receptor 4, which is an essential component of cellular recognition of bacterial lipopolysaccharide. Hind paw sensitivity to thermal stimulus was quantitatively determined 1, 2, 7 and 14 days after infection.

RESULTS

Intravesical instillation of E. coli produced infection in all strains of mice. Infection persisted in all C3H/OuJ and C3H/HeJ mice but it spontaneously cleared in some C57BL/6N mice. Increased sensitivity to thermal stimuli was observed in C57BL/6N and C3H/OuJ mice starting 1 to 2 days after E. coli instillation and it was still present 14 days after instillation. Increased sensitivity to thermal stimuli did not occur in C3H/HeJ mice.

CONCLUSIONS

E. coli induced cystitis produced increased sensitivity to peripheral thermal stimuli in mice with competent toll-like receptor 4.

Treatment of chronic pelvic pain in men and women

Chronic pelvic pain syndrome (CPPS) is a common condition that is encountered by a variety of healthcare professionals. Unfortunately, physicians often misdiagnose this problem or recommend inappropriate and sometimes dangerous treatments that offer little hope of successful outcome. In addition, CPPS is typically a multifaceted disorder, simultaneously compromising psychological, peripheral nerve, autonomic, central nervous, visceral, connective tissue, hormonal and other systems. Thus, solo practitioners who may correctly diagnose CPSS are often ill-equipped to provide adequate comprehensive, multidisciplinary treatment. This article is intended as an overview of the most recent literature in support of various treatment modalities for chronic pelvic pain in men and women. We advocate a team-oriented approach in the treatment of CPPS, which employs the coordinated efforts of multiple practitioners, ideally in a subspecialty care setting.