Neuroinflammatory gene expression analysis reveals potential novel mediators and treatment targets in interstitial cystitis with Hunner lesions

Background

We sought to study differential neuroinflammatory gene expression in men with interstitial cystitis (IC) with Hunner lesions compared with asymptomatic controls using NanoString, which uses barcoded probes to measure hundreds of genes. IC is a heterogenous condition lacking reliable biomarkers, and a subset of patients exhibits Hunner lesions, implicating the bladder as an inflammatory pain generator.

Methods

Blood, urine, and bladder biopsies were collected from 6 men with IC and Hunner lesions. 7 asymptomatic controls had blood and urine collected and 2 benign bladder biopsies were obtained from our tissue bank. RNA was isolated and analyzed with NanoString Human Neuroinflammation panel. Gene expression was considered significant if there was a >1.5-fold change and adjusted P value <0.05 compared with controls.

Results

Mean patient age was 61.5 years with 8 years median symptom duration. In bladder tissue, while many cytokine and chemokine genes had higher expression as expected (e.g., TNF, CXCL10), other significant genes included TRPA1 (1098-fold increased, expressed in pain sensing neurons) and TNFRSF17 (735-fold, B-cell related). In urine, there was 114-fold increase in S1PR4, which mediates pain via TRP-dependent pathways. A patient on cyclosporine had lower inflammatory gene expression levels relative to other IC patients, but no difference in TRPA1.

Conclusions

Men with IC and Hunner lesions have a diverse set of neuroinflammatory genes with differential expression compared to controls. We identified genes linked to neuropathic pain through the TRP pathway and this expression was not reduced by cyclosporine. These findings open a new direction for biomarker and therapeutic discovery.

Interstitial cystitis intravesical therapy

Interstitial cystitis (IC) is a progressive bladder disorder that presents with symptoms of bladder urgency, frequency and pain. The aetiology of the disease remains uncertain, but it is postulated that there is an initial infective insult which damages the glycosaminoglycan (GAG) layer of the bladder urothelium. This defect allows an influx of ions, particularly potassium, which initiates an inflammatory reaction in the bladder wall, which incites the symptoms described above. Treatment initially involves behavioural and oral medication, with second line being intravesical instillation therapy. Treatment strategies focus on restoring lower urinary tract epithelial function, inhibiting neural activation, controlling allergies and relieving symptoms. In this review, current intravesical therapy will be discussed, as well as what lies on the horizon for intravesical therapy in IC.

Clinical presentation and treatment of bladder pain syndrome/interstitial cystitis (BPS/IC) in India

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic disease characterized by pelvic pain urgency and frequency. Patients with severe symptoms lead a very miserable life. North American, European and Asian guidelines have been recently promulgated but they differ on many important issues. There is no consensus on its name, definition, investigations and management. Indian guidelines have also been developed and they give more importance to the symptoms in relation to micturition. Though initially believed to be rare or non-existent in India the situation has changed. In Indian patients the presentation is more or less same as the rest of the world but a large percentage have obstructive symptoms and unusual urinary symptoms. Anal discomfort is also common. In India the commonest investigation in all cases of lower urinary tract (LUT) dysfunction is ultrasonography of kidney ureter and bladder with measurement of the post void residual urine volume. Cystoscopy is also done in all the cases to rule out presence of tuberculosis or carcinoma in situ. Bladder pain syndrome/interstitial cystitis (BPS/IC) is not considered to be a clinical disease as it is difficult to rule out all differential diagnosis only from history. Hunner’s lesion is very rare. Cystoscopy with hydro distension, oral therapy, intravesical therapy and surgical therapy form the back bone of management. It is difficult to know which treatment is best for a given patient. A staged protocol is followed and all the treatment modalities are applied to the patients in a sequential fashion—starting from the non-invasive to more invasive. Intravesical botox has not been found to be effective and there is no experience with interstim neuromodulation.

In what type of interstitial cystitis/bladder pain syndrome is DMSO intravesical instillation therapy effective?

Background

Dimethylsulfoxide (DMSO) is the most-used agent for intravesical instillation. We conducted this retrospective clinical study to determine in what type of the interstitial cystitis (IC)/bladder pain syndrome (BPS) DMSO was effective.

Methods

We combined DMSO with hydrodistension in 2003 and from 2004 we performed hydrodistension alone. Hydrodistension had been performed in 7 cases of IC/BPS with Hunner’s lesions (H group) and 7 cases of IC/BPS without Hunner’s lesions (non-H group), and they served as the control group (C group; n=14). There was also a DMSO group (D group; n=14) that consisted of an H group of 7 cases and an non-H group of 7 cases in which the hydrodistension had been immediately followed by intravesical instillation of 50% DMSO 50 mL. Before, and 2, 6, 12, 18, and 24 months (M) after the intervention, the patients were asked to complete a 4-day frequency-volume chart (FVC) and the O’Leary-Sant IC symptom index (ICSI) questionnaire and IC problem index (ICPI) questionnaire, and to rate their pain on a visual analogue scale (VAS).

Results

All parameters were improved after hydrodistension in both the C group and the D group. However, comparison of the C group and D group according to whether Hunner lesions were present showed that there were no significant differences in any of the postoperative parameters between the non-H groups in the C group and D group, but in the H groups, average and maximum voided volume were significantly higher and the ICSI, ICPI, and VAS scores were lower in the D group. Moreover, the significant differences increased with the duration of the postoperative period.

Conclusions

DMSO intravesical instillation therapy was useful in both maintaining and improving the effectiveness of hydrodistension in IC/BPS with Hunner lesions. However, DMSO did not have any particular efficacy in the treatment of IC/BPS in the absence of Hunner lesions.

How does interstitial cystitis begin?

BACKGROUND

Interstitial cystitis (IC) does not start as an endstage disease, it has a beginning when symptoms are milder, intermittent and the disease is misdiagnosed. To determine how IC develops patients were interviewed on when their symptoms began, what they were and are now as well as the various diagnoses that they received before they were determined to have IC.

METHODS

One hundred female IC patients were screened. They filled out a questionnaire asking about the age their disease presented, their initial and current symptoms, what their original diagnoses were, effect of the menstrual cycle and sexual activity on their symptoms and about any relatives with bladder symptoms or a current diagnosis of IC.

RESULTS

By age 30, 81% of patients had bladder symptoms, 21% before age 10. The first symptom was frequency in 81%, pain present in 59% and the symptoms were intermittent in 64%. Most common early misdiagnosis was UTI in 74% with 93% reporting negative urine cultures. Sex was painful and causes symptom flares in 82%, symptoms flared the week before the menses in 75%. Most common gynecologic diagnosis was yeast vaginitis, 42%. Urge incontinence was present in 33%. There were 51% that reported bladder symptoms in a first degree female relative.

CONCLUSIONS

IC begins primarily with frequency and is intermittent in most patients with symptom flares associated with sexual activity. Pain and urgency incontinence tend to be a later symptoms. When IC flares the most common misdiagnosis is UTI. Symptoms begin before age 30 in most but an IC diagnosis is often not made until age 40. Genetics appear to play a significant role. It is important to consider these facts when evaluating women with "early IC" because correct diagnosis will result in proper therapy and reduced health care costs.

Current guidelines in the management of interstitial cystitis

Interstitial cystitis (IC) is a heterogeneous chronic disease of unknown etiology that impacts a very large number of women. Symptoms are highly variable: patients may suffer from pelvic pain that is exacerbated by bladder filling, and can be associated with a variety of lower urinary tract symptoms including frequency and urgency. Given the varying presentations and severities of corresponding treatment must be tailored to each specific patient. Current American Urological Association (AUA) guidelines separate the IC treatment recommendations into six tiers of increasing invasive therapies. These treatment guidelines begin with education and lifestyle modifications and progress through levels of physical, pharmacological, and ultimately surgical therapies for those that fail the less invasive therapies. The purpose of this review is to outline the recommendations for the treatment of IC and the evidence from which these recommendations arise. Furthermore, we examine the most up to date literature so that we may recognize future directions in the treatment of IC.

A survey on clinical practice of interstitial cystitis in Japan

Background

To explore the real-life practice of clinical management of interstitial cystitis (IC) in Japan.

Methods

A questionnaire on the number of IC patients, cystoscopic findings, diagnostic methods, and the treatment modalities was sent via e-mail to 114 medical institutions belonging to the Society of Interstitial Cystitis of Japan (SICJ).

Results

Completed questionnaires were returned from 62 institutions (20 university hospitals, 26 general hospitals and 16 clinics), with a response rate of 54%. The median of patient number per institution was 20 and the national number of IC patients was counted as 4,531 in Japan. The number of new patients in 2013 was 7 (median) per institution and calculated as 1,214 in total. The case volume per institution distributed broadly and skewed to a lower volume. The patients were categorized according to cystoscopic findings as either Hunner type IC with Hunner lesions (n=2,066, 45%), non-Hunner type IC with glomerulations on hydrodistension (n=1,720, 38%) or hypersensitive bladder without endoscopic abnormalities (n=304, 7%), excluding unknown (n=441, 10%). The proportion of Hunner type IC was highly variable among the institutions, ranging from 0% to 100% with a median of 29%. As for evaluation, symptom and quality of life (QOL) assessment by questionnaires, frequency volume chart, urinalysis, urine cytology, urine culture, post-void residual measurement, uroflowmetry, ultrasound and cystoscopy were widely adapted. Administration of oral medicines and intravesical instillation therapy were undertaken at 98% and 63% of institutions, respectively. Hydrodistension was commonly performed, totaling in 812 procedures at 53 institutions, while only five cystectomies were reported from four institutions.

Conclusions

The survey estimated about 4,500 IC patients and 2,000 Hunner type IC patients in Japan. It also revealed a wide range of case volume, acceptable adherence to clinical guidelines, and high variability in the proportion of Hunner type IC. The variable proportions of Hunner type IC despite a high performing rate of endoscopy suggest inconsistency in diagnostic criteria for the Hunner lesion.

Role of cystoscopy and hydrodistention in the diagnosis of interstitial cystitis/bladder pain syndrome

There are controversies about whether cystoscopy with or without hydrodistention (HD) plays a role in the diagnosis and treatment of interstitial cystitis/bladder pain syndrome (IC/BPS). We reviewed the recommendations of various societies and associations of greater impact in this complex disease, analyzing the indications, technique, findings and complications of this procedure.

Interstitial cystitis/painful bladder syndrome: the influence of modern diagnostic criteria on epidemiology and on Internet search activity by the public

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic debilitating condition that is characterised by suprapubic pain and urinary symptoms such as urgency, nocturia and urinary frequency. The prevalence of the condition is increasing due to more inclusive diagnostic criteria. Herein, we review the evolving epidemiology of IC/PBS and investigate health seeking behaviour for the condition through Internet search activity. Study selection was performed in accordance with PRISMA. In addition, global search trends for the terms ‘Interstitial Cystitis’ and ‘Painful Bladder Syndrome’ from 2005 to 2015 were also evaluated using the ‘Google Trends’ search application. The mean search activity per month was recorded and mean activity at annual intervals calculated. Regional search activity by country and city was also measured. Prevalence rates for IC/PBS vary according to diagnostic criteria and range from 2% to 17.3% among the general population. Increased prevalence is associated with female gender and females with one first-degree relative affected. There has been an increase in global mean search activity for IC/PBS on an annual basis since 2005. The greatest increase in search activity was in USA, Canada, United Kingdom, Australia, Ireland and India respectively. The top five cities for search activity for IC/PBS were in the USA. As diagnostic criteria for IC/PBS continues to become more inclusive it is likely that the prevalence will continue to increase. This is particularly true for the USA and Canada as these regions have demonstrated the greatest increase in Internet search activity for IC/ PBS.

Complementary and alternative medical therapies for interstitial cystitis: an update from the United States

The diagnosis and treatment of interstitial cystitis/bladder pain syndrome (IC/BPS) has shifted from organ-specific to a multifactorial, multidisciplinary and individualized approach. Patients with refractory and debilitating symptoms may respond to complementary and alternative medical treatments (CAM). Through CAM therapies, practitioners assist the patient to be at the center of their care, empowering them to be emotionally and physically involved. Multi-disciplinary care, including urology, gynecology, gastroenterology, neurology, psychology, physiotherapy and pain medicine, is also identified to be the crux of adequate management of patients with chronic pelvic pain because of its variable etiology. The purpose of this review is to emphasize these changes and discuss management strategies.

Novel research approaches for interstitial cystitis/bladder pain syndrome: thinking beyond the bladder

Despite years of basic and clinical research focused on interstitial cystitis/bladder pain syndrome (IC/BPS), including clinical trials of candidate therapies, there remains an insufficient understanding of underlying cause(s), important clinical features and a lack of effective treatments for this syndrome. Progress has been limited and is likely due to many factors, including a primary focus on the bladder and lower urinary tract as origin of symptoms without adequately considering the potential influence of other local (pelvic) or systemic factors. Traditionally, there has been a lack of sufficiently diverse expertise and application of novel, integrated methods to study this syndrome. However, some important insights have been gained. For example, epidemiological studies have revealed that IC/BPS is commonly associated with other chronic pain conditions, including fibromyalgia, irritable bowel syndrome and chronic fatigue syndrome. These observations suggest that IC/BPS may involve systemic pathophysiology, including alterations of the central nervous system in some patients. Furthermore, there may be multiple causes and contributing factors that manifest in the symptoms of IC/BPS leading to multiple patient sub-groups or phenotypes. Innovative research is necessary to allow for a more complete description of the relationship between this syndrome and other disorders with overlapping symptoms. This report provides examples of such innovative research studies and their findings which have the potential to provide fresh insights into IC/BPS and disorders associated with chronic pain through characterization of broad physiologic systems, as well as assessment of the contribution of the bladder and lower urinary tract. They may also serve as models for future investigation of symptom-based urologic and non-urologic disorders that may remain incompletely characterized by previous, more traditional research approaches. Furthermore, it is anticipated a more holistic understanding of chronic urologic pain and dysfunction will ensue from productive interactions between IC/BPS studies like those described here and broader cutting-edge research endeavors focused on potentially related chronic pain disorders. A more comprehensive vision for IC/BPS inquiry is anticipated to yield new insights into basic disease mechanisms and clinical characteristics that will inform future research studies that will lead to more effective therapies and improved clinical care for these patients.