Bladder Capacity is a Biomarker for a Bladder Centric versus Systemic Manifestation in Interstitial Cystitis/Bladder Pain Syndrome

Temporally complex inflammatory networks in an animal model reveal signatures for interstitial cystitis and bladder pain syndrome phenotype

INTRODUCTION AND OBJECTIVE

Interstitial cystitis and bladder pain syndrome (IC/BPS) presents with symptoms of debilitating bladder pain and is typically a diagnosis of exclusion. The cystoscopic detection of Hunner's lesions increases the likelihood of detecting tissue inflammation on bladder biopsy and increases the odds of therapeutic success with anti-inflammatory drugs. However, the identification of this subgroup remains challenging with the current lack of surrogate biomarkers of IC/BPS. On the path towards identifying biomarkers of IC/BPS, we modeled the dynamic evolution of inflammation in an experimental IC/BPS rodent model using computational biological network analysis of inflammatory mediators (cytokines and chemokines) released into urine. The use of biological network analysis allows us to identify urinary proteins that could be drivers of inflammation and could therefore serve as therapeutic targets for the treatment of IC/BPS.

METHODS

Rats subjected to cyclophosphamide (CYP) injection (150 mg/kg) were used as an experimental model for acute IC/BPS (n = 8). Urine from each void was collected from the rats over a 12-h period and was assayed for 13 inflammatory mediators using Luminex™. Time-interval principal component analysis (TI-PCA) and dynamic network analysis (DyNA), two biological network algorithms, were used to identify biomarkers of inflammation characteristic of IC/BPS over time.

RESULTS

Compared to vehicle-treated rats, nearly all inflammatory mediators were elevated significantly (p < 0.05) in the urine of CYP treated rats. TI-PCA highlighted that GRO-KC, IL-5, IL-18, and MCP-1 account for the greatest variance in the inflammatory response. At early time points, DyNA indicated a positive correlation between IL-4 and IL-1β and between TNF-α and IL-1β. Analysis of TI-PCA and DyNA at later time points showed the emergence of IL-5, IL-6, and IFNγ as additional key mediators of inflammation. Furthermore, DyNA network complexity rose and fell before peaking at 9.5 h following CYP treatment. This pattern of inflammation may mimic the fluctuating severity of inflammation associated with IC/BPS flares.

CONCLUSIONS

Computational analysis of inflammation networks in experimental IC/BPS analysis expands on the previously accepted inflammatory signatures of IC by adding IL-5, IL-18, and MCP-1 to the prior studies implicating IL-6 and GRO as IC/BPS biomarkers. This analysis supports a complex evolution of inflammatory networks suggestive of the rise and fall of inflammation characteristic of IC/BPS flares.

Postsurgery Opiate Use Is Significantly Lower in Patients With Interstitial Cystitis/Bladder Pain Syndrome Following Cystectomy With Urinary Diversion

OBJECTIVE

To compare pre-and post-operative opiate use in a large cohort of interstitial cystitis/bladder pain syndrome (IC/BPS) patients who underwent cystectomy with urinary diversion (CWUD).

METHODS

A retrospective analysis was completed using a database of IC/BPS patients who underwent CWUD at a single institution from 2014 to 2022. In addition to demographic information, bladder capacity and Hunner lesion status were documented for each patient. Opiate use (milligram morphine equivalents [MME]) was calculated for each patient and change in MME (ΔMME) was calculated by subtracting pre-CWUD MME from post-CWUD MME. Paired t test was used to compare ΔMME for all parameters except age, where a Pearson's correlation was used.

RESULTS

The analysis included 82 patients (17 M; 65 F) that underwent CWUD as follows: 53 ileal conduit diversions, 11 neobladders, and 18 Indiana Pouches. Mean pre-CWUD MME use was 4509.57 and mean post-CWUD MME was 1788.48 with a ΔMME of - 2721.09 (P < .001). ΔMME was not significantly different based on gender (P = .597), bladder capacity (P = .754), age (P = .561), or Hunner lesion status (P = .085).

CONCLUSION

IC/BPS patients using opiates primarily for relief of pain directly related to their condition show a significant decrease in opiate use following CWUD, which likely represents significant pain reduction and implicates the bladder as the primary source of that pain.

Sensory Receptor, Inflammatory, and Apoptotic Protein Expression in the Bladder Urothelium of Patients with Different Subtypes of Interstitial Cystitis/Bladder Pain Syndrome

The aim of this study was to investigate the expression levels of sensory receptors, inflammatory proteins, and pro-apoptotic proteins in the urothelium of non-Hunner's interstitial cystitis (NHIC) bladders of patients with different clinical and cystoscopic phenotypes. The urothelia from the bladders of 52 NHIC patients were harvested. The expression of sensory receptors, including TRPV1, TRPV4, TRPA1, H1-receptors, and sigma-1 receptors; the inflammatory proteins p38 and tryptase; and the pro-apoptotic proteins, such as caspase-3, BAD, and BAX in the urothelium, were investigated using immunohistochemistry and Western blotting. We compared the expression levels of these proteins in NHIC subtypes according to IC symptom scores, visual analog scores of bladder pain, maximal bladder capacity, glomerulation grades, and combined maximal bladder capacity and glomerulations after cystoscopic hydrodistention. The expression levels of TRPV1, TRPV4, sigma-1, P38, tryptase, caspase-3, and BAD were significantly increased in the urothelium of IC/BPS patients compared with the expression levels in the controls. TRPV1 was significantly associated with IC symptom severity. However, no significant differences in sensory receptor expression in the IC/BPS bladders with different bladder conditions were detected. Inflammatory and pro-apoptotic protein expression levels in the urothelium were similar among the IC/BPS subgroups. This study concluded that IC/BPS patients with frequency and bladder pain complaints have higher levels of urothelial sensory receptors, and inflammatory and pro-apoptotic proteins. The expression levels of these sensory receptors, inflammatory proteins, and pro-apoptotic proteins are not significantly different among IC/BPS bladders with different conditions.

Clinical Approach to Recurrent Voiding Dysfunction, Dysuria, and Pelvic Pain Persisting for at Least 3 Months

There are several patients with urination problems and urethral and pelvic discomfort. Usually, these patients’ symptoms are persistent and ambiguous; therefore, it is difficult to find underlying diseases associated with the patient’s symptoms. In addition, there are various conditions such as overactive bladder, cystitis, and interstitial cystitis/bladder pain syndrome (IC/BPS). Sometimes patients with other chronic disorders such as fibromyalgia, inflammatory bowel syndrome, and vulvodynia show urination problems and pelvic pain. Thus, a patient-centered approach is important to find the cause of chronic urination problems and pelvic pain. Moreover, IC/BPS should be considered during the diagnostic process because the clinical characteristics of IC/BPS are diverse. In this narrative review, we suggest an integral approach for the diagnosis and treatment of 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.

Pediatric cystectomy for refractory cystitis post-bone marrow transplant in dyskeratosis congenita: A case report

We present a case of refractory cystitis after BK-virus associated hemorrhagic cystitis following bone marrow transplantation requiring cystectomy in a 17-year-old female with genetically confirmed dyskeratosis congenita, a telomere disorder characterized by early bone marrow failure. She presented with a contracted, small bladder with intense urinary symptoms non-responsive to conservative therapy and requiring opioids for pain control. Cystectomy is a rare, final surgical treatment for benign bladder conditions, especially among younger patients, and she experienced successful resolution of symptoms and cessation of chronic opioids post-intervention.

Pulsed Electromagnetic Field Therapy for Pain Management in Interstitial Cystitis/Bladder Pain Syndrome: A Proof-of-Concept Case Series

OBJECTIVE

To evaluate the efficacy of pulsed electromagnetic field (PEMF) therapy for symptom and pain management in women with non-bladder centric interstitial cystitis/bladder pain syndrome (IC/BPS).

METHODS

Women with non-bladder centric IC/BPS and a numeric rating scale score for pelvic pain ≥6 underwent twice-daily 8-minute full body PEMF therapy sessions for 4 weeks. The primary outcome metric was a reduction in pelvic pain score ≥2 points. A 7-day voiding diary (collected at baseline and conclusion), 3 validated symptom scores, and the Short Form-36 Quality of Life questionnaire (completed at baseline, conclusion of treatment, and 8-week follow-up), were used to assess secondary outcomes. Treatment effects were analyzed via Wilcoxon-signed rank test; P < .05 was considered significant.

RESULTS

The 4-week treatment protocol was completed by 8 of 10 enrolled patients, and 7:8 (87.5%) had a significant reduction in pelvic pain (-3.0 points, P = .011) after 4 weeks. There was also a significant decrease in scores on all validated IC/BPS questionnaires, daily number of voids, and nocturia symptom score (P < .05). Significant increases in several quality-of-life questionnaire sub-scores were also identified at 4 weeks (P < .05). At 8-week post-therapy, the positive effects were somewhat attenuated, yet 4:8 patients (50%) continued to have significant pain reduction (P = .047). No adverse events or side effects were reported.

CONCLUSION

Whole body pulsed electromagnetic field therapy is an alternative treatment option for women with chronic bladder pain syndrome that warrants investigation through comparative trials.

Use of Urinary Cytokine and Chemokine Levels for Identifying Bladder Conditions and Predicting Treatment Outcomes in Patients with Interstitial Cystitis/Bladder Pain Syndrome

BACKGROUND

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a condition causing bladder inflammation. Urinary biomarkers have been assessed as suitable for the diagnosis and treatment. This study aimed at investigating the role of urinary biomarkers in identifying bladder conditions and predicting the treatment outcome of IC/BPS.

METHODS

A total of 309 patients with IC/BPS and 30 controls were enrolled in this study. All patients underwent a comprehensive urological workup of symptoms, pain severity, and cystoscopic hydrodistention findings including maximal bladder capacity (MBC) and glomerulation grade. Urine samples were collected to investigate the levels of urinary cytokines and chemokines. According to MBC and glomerulation grade, patients with IC/BPS were further classified into the Hunner's IC (HIC) and non-HIC groups. The urinary biomarkers between IC/BPS and control groups and HIC and non-HIC groups were compared. Moreover, the treatment response was graded according to global response assessment (GRA) scores, and urinary biomarker levels were analyzed based on different GRAs.

RESULTS

Patients with IC/BPS had significantly high urinary monocyte chemoattractant protein-1, eotaxin, tumor necrosis factor -alpha (TNF-α), and prostaglandin E2 levels. Significantly higher levels of urinary interleukin-8, C-X-C motif chemokine ligand 10 (CXCL 10), brain-derived neurotrophic factor, eotaxin, and regulated-on-activation, normal T-cell expressed and secreted (RANTES) were noted in HIC than those with non-HIC and controls. Among all biomarkers, TNF-α had the best sensitivity, specificity, positive predictive value, and negative predictive value. There was a significant correlation between biomarker levels and GRA.

CONCLUSIONS

Significantly higher urine cytokines and chemokine levels were found in patients with IC/BPS. Most urinary biomarkers were significantly associated with MBC, glomerulation grade, and treatment outcome.

Reduction of Bladder Capacity Under Anesthesia Following Multiple Recurrences and Repeated Surgeries of Hunner Lesions in Patients With Interstitial Cystitis

Purpose

To investigate the influence of multiple recurrences and repeated surgeries of Hunner lesions on bladder capacity under general anesthesia in patients with interstitial cystitis (IC).

Methods

We retrospectively reviewed the clinical records of Hunner-type IC (HIC) patients who underwent transurethral fulguration or resection of Hunner lesions combined with hydrodistension by a single surgeon between 2011 and 2020. Recurrence was defined as reappearance of uncontrolled urinary symptoms in association with new Hunner lesions identified by cystoscopy. Recurrent Hunner lesions were then treated by transurethral surgeries. The recurrence-free rate, potential predictive factors of recurrence, and changes in bladder capacity under anesthesia were examined at each surgical procedure.

Results

A total of 92 surgeries were performed in 47 HIC patients, 23 (49%) of whom required multiple procedures (range, 1–5 times). The mean recurrence-free time after the first surgery was 21.7 months. The recurrence-free rate was 53% at 24 months, and decreased to 32% at 48 months. There were no significant differences in age, sex, bladder capacity under anesthesia at the first surgery, duration from symptom onset to the first surgery, O’Leary-Sant questionnaire including symptom and problem indexes, visual analogue scale pain score, and the number of comorbidities between the cases with or without recurrence. Bladder capacity under anesthesia was gradually decreased as the number of surgeries was increased, and bladder capacity at the fourth procedure was significantly decreased to 80% of the capacity at the first surgery.

Conclusions

These results suggest that multiple recurrences and repeated surgeries of Hunner lesions result in a reduction of bladder capacity under anesthesia in HIC patients although no predictive factors for recurrence of Hunner lesions were detected.

Evidence for Early Cyclosporine Treatment for Hunner Lesion Interstitial Cystitis

OBJECTIVES

The objective of this study was to evaluate our experience using cyclosporine A (CyA) in the treatment of Hunner lesion interstitial cystitis (HLIC).

METHODS

Retrospective chart review was performed on patients with HLIC treated with CyA from August 2012 to September 2019. Demographic and clinical variables, number of interstitial cystitis therapies, frequency, nocturia, and bladder pain visual analog scores before and after CyA treatment were collected, as well as the Global Response Assessment (GRA) and the Interstitial Cystitis Symptom Index and Interstitial Cystitis Problem Index. CyA responders were defined as those with moderately or markedly improved GRA scores.

RESULTS

A total of 51 patients with HLIC treated with CyA were identified. Mean follow-up was 3 years (0.36-6.8 years). Seventy-six percent (28 of 37) were female; mean age was 68 years (51-84 years). Before CyA treatment, an average of 8 previous therapies were tried and patients reported an average of 8 of 10 bladder pain. Daytime frequency was 11-20 times per day, and nocturia was 7 times per night. Per the GRA, 84% (31 of 37) were considered CyA responders. Posttherapy Interstitial Cystitis Symptom Index and Interstitial Cystitis Problem Index scores were lower in responders compared with nonresponders (8.9 ± 5.7 vs 21.3 ± 7.0, P = 0.001). Bladder pain, number of hydrodistentions/fulgurations, nocturia, and daytime frequency improved significantly after CyA treatment.

CONCLUSIONS

The cyclosporine A response rate was 84%, with most of these patients reporting marked improvement. Bladder pain, daytime frequency, and nocturia were significantly improved after CyA treatment, and the number of interventions after CyA treatment decreased. Cyclosporine A should be considered earlier than fifth-line therapy in HLIC.

Low-pressure hydrodistension induces bladder glomerulations in female patients with interstitial cystitis/bladder pain syndrome

AIMS

The role of hydrodistension in the diagnosis of interstitial cystitis/bladder pain syndrome (IC/BPS) is controversial. This study evaluated the effect of low-pressure hydrodistension on glomerulation formation in female patients diagnosed with the disease.

METHODS

Sixty female patients with the clinical diagnosis of IC/BPS and 30 female controls without the disease underwent cystoscopy and hydrodistension. Cold-cup biopsy was taken from bladder posterior wall at sites with normal cystoscopic appearance before hydrodistension in the IC/BPS group. The tissue samples were processed for histology study. Low-pressure (40 cmH₂ O) hydrodistension for 2 min was performed and the appearance of glomerulations was compared between the two groups. High-pressure (80 cmH₂ O) hydrodistension for 8 min was then performed as a therapeutic measure for the IC/BPS patients. Further changes to the degree of glomerulations were recorded.

RESULTS

Histology showed pathological changes in the normal-appearing IC/BPS bladder mucosa including urothelium denudation, inflammatory cell infiltration, stromal edema, fibrosis, and vascular congestion. Low-pressure hydrodistension induced significant glomerulation formation in the patient group (percentage of patients with Grades 0-4: 0%, 8.3%, 40%, 35%, 10%, respectively) while none in the controls. High-pressure hydrodistension further increased the glomerulation grading in the IC/BPS patients.

CONCLUSIONS

Structural changes are present in prehydrodistension IC/BPS bladder wall, which may not be macroscopically detectable. Hydrodistension at low pressure is adequate to disrupt the integrity of such diseased mucosa and offers a more discriminative test in the diagnosis of IC/BPS.

Voiding defects in acute radiation cystitis driven by urothelial barrier defect through loss of E-cadherin, ZO-1 and Uroplakin III

Long term-side effects from cancer therapies are a growing health care concern as life expectancy among cancer survivors increases. Damage to the bladder is common in patients treated with radiation therapy for pelvic cancers and can result in radiation (hemorrhagic) cystitis (RC). The disease progression of RC consists of an acute and chronic phase, separated by a symptom-free period. Gaining insight in tissue changes associated with these phases is necessary to develop appropriate interventions. Using a mouse preclinical model, we have previously shown that fibrosis and vascular damage are the predominant pathological features of chronic RC. The goal of this study was to determine the pathological changes during acute RC. We identified that radiation treatment results in a temporary increase in micturition frequency and decrease in void volume 4–8 weeks after irradiation. Histologically, the micturition defect is associated with thinning of the urothelium, loss of urothelial cell–cell adhesion and tight junction proteins and decrease in uroplakin III expression. By 12 weeks, the urothelium had regenerated and micturition patterns were similar to littermate controls. No inflammation or fibrosis were detected in bladder tissues after irradiation. We conclude that functional bladder defects during acute RC are driven primarily by a urothelial defect.

Anesthetic Bladder Capacity is a Clinical Biomarker for Interstitial Cystitis/Bladder Pain Syndrome Subtypes

OBJECTIVE

To further examine anesthetic bladder capacity as a biomarker for interstitial cystitis/bladder pain syndrome (IC/BPS) patient subtypes, we evaluated demographic and clinical characteristics in a large and heterogeneous female patient cohort.

MATERIAL AND METHODS

This is a retrospective review of data from women (n = 257) diagnosed with IC/BPS who were undergoing therapeutic bladder hydrodistention (HOD). Assessments included medical history and physical examination, validated questionnaire scores, and anesthetic BC. Linear regression analyses were computed to model the relationship between anesthetic BC and patient demographic data, symptoms, and diagnoses. Variables exhibiting suggestive correlations (P ≤ .1) were candidates for a multiple linear regression analysis and were retained if significant (P ≤ .05).

RESULTS

Multiple regression analysis identified a positive correlation between BC and endometriosis (P = .028) as well as negative correlations between BC and both ICSI score (P < .001) and the presence of Hunner's lesions (P < .001). There were higher average numbers of pelvic pain syndrome (PPS) diagnoses (P = .006) and neurologic, autoimmune, or systemic pain (NASP) diagnoses (P = .003) in IC/BPS patients with a non-low BC, but no statistical difference in the duration of diagnosis between patients with low and non-low BC (P = .118).

CONCLUSION

These data, generated from a large IC/BPS patient cohort, provide additional evidence that higher BC correlates with higher numbers of non-bladder-centric syndromes while lower BC correlates more closely with bladder-specific pathology. Taken together, the results support the concept of clinical subgroups in IC/BPS.

Trigone as a diagnostic and therapeutic target for bladder-centric interstitial cystitis/bladder pain syndrome

The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) may be bladder-centric, with afferent nerve hyperexcitability and/or due to neural central sensitization. In bladder-centric disease, the trigone's unmyelinated nociceptive C-fibers are thought to be upregulated, suggesting this as a potential target for diagnostic modalities and for treatment with local anesthetics and chemodenervation. We propose that the transvaginal trigone treatment (T3) route of administration of such treatments should be considered in women with IC/BPS, as this approach is easier and less invasive than cystoscopy. For T3, or other bladder-centric treatments to be successful, patient selection should attempt to exclude patients with predominantly neural central sensitization.

Cystoscopic hydrodistention characteristics provide clinical and long-term prognostic features of interstitial cystitis after treatment

To evaluate the correlations of clinical symptoms, urodynamic parameters, and long-term treatment outcomes with different findings of cystoscopic hydrodistention (HD) in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). This retrospective analysis of 486 patients with IC/BPS investigated baseline clinical symptoms, disease duration, medical comorbidities, urodynamic findings, cystoscopic characteristics [including maximal bladder capacity (MBC) and the presence of glomerulations and Hunner’s lesions], and outcomes according to the five IC/BPS HD subtypes based on the glomerulation grade, MBC, and the presence of Hunner’s lesions. Receiver operation characteristic analysis identified an optimal cutoff value of MBC ≥ 760 ml as a predictor of satisfactory outcomes. Glomerulation grade and MBC were significantly correlated (r =  − 0.403, P < 0.001), and both were significantly associated with IC Symptom Index scores. The rate of satisfactory outcomes was better for the patients with low glomerulation grade and MBC ≥ 760 ml (64.2%), and significantly worse for those with Hunner’s lesions (36.8%); no significant differences were noted among the other groups. The results suggested that IC/BPS patients can be classified into the following three distinct subgroups: (1) those with low glomerulation grade and MBC ≥ 760 ml; (2) those with low glomerulation grade and MBC < 760 ml, or with high glomerulation grade regardless of MBC; and (3) those with Hunner’s lesions. The results showed that three IC/BPS subgroups had distinct bladder characteristics and treatment outcomes. The patients with high MBC and low glomerulation grade after HD had more medical comorbidities but a significantly higher rate of satisfactory treatment outcome.

IRB: 105-25-B.

Small Fiber Polyneuropathy Is Associated With Non-Bladder-Centric Interstitial Cystitis/Bladder Pain Syndrome Patients

OBJECTIVES

Interstitial cystitis/bladder pain syndrome (IC/BPS) comprises at least 2 phenotypes. Bladder centric patients typically demonstrate low bladder capacity (BC), often with Hunner lesion (HL), whereas non-bladder-centric patients typically have normal cystoscopic findings and more co-occurring nonurologic symptoms/syndromes (NUS), contributing to widespread pain beyond the bladder. Small fiber polyneuropathy (SFPN) is significantly associated with fibromyalgia, a frequent IC/BPS codiagnosis and may play an etiologic role in IC/BPS. We assessed SFPN status in bladder-centric versus non-bladder-centric IC/BPS patients.

METHODS

Distal leg biopsies were obtained from 11 IC/BPS patients after therapeutic hydrodistention. Specimens were embedded/sectioned per standard protocol and stained for protein gene product 9.5, an intraepidermal nerve fiber marker. To determine SFPN status, intraepidermal nerve fiber density was calculated and compared with normative reference values stratified by age/sex. The SFPN prevalence and reported comorbidities were compared between low BC and/or HL-positive (bladder-centric) versus non-low BC, HL (non-bladder-centric) patients.

RESULTS

Seven patients (63.6%) were SFPN positive. Non-bladder-centric patients demonstrated significantly more SFPN (6/7, 85.7%) compared with bladder-centric patients (1/4, 25.0%; P = 0.027). Non-bladder-centric patients also reported more comorbid NUS overall (1.25 ± 0.83 vs 5.86 ± 2.47; P = 0.003), including fibromyalgia (P = 0.010), migraines (P = 0.035), anxiety/panic disorder (P = 0.035), allergies (P = 0.027), and asthma (P = 0.035).

CONCLUSIONS

In this pilot study, SFPN was significantly more common in non-bladder-centric IC/BPS, that is, those patients who also reported greater prevalence of NUS, including fibromyalgia, migraines, anxiety/panic disorders, allergies, and asthma. These findings suggest that SFPN may have an etiologic role in a larger, systemic pain syndrome and should be explored further.

Clinical characterization of interstitial cystitis/bladder pain syndrome in women based on the presence or absence of Hunner lesions and glomerulations

OBJECTIVES

To compare the clinical characteristics of three groups of female patients with interstitial cystitis/bladder pain syndrome (IC/BPS) classified according to the presence or absence of Hunner lesions (HL) and glomerulations.

METHODS

The clinical records of 100 female patients with IC/BPS who underwent their first bladder hydrodistension at our institution were retrospectively reviewed. They were divided into patients having (HL-IC; n = 57) or lacking (BPS; n = 43) HL. BPS patients were further classified as those with (29) and without (14) glomerulations. Among these three subtypes, demographics, comorbidities, symptom parameters including a visual analog scale for pain scores, O'Leary and Sant Symptom and Problem (OSSI/OSPI) Indices, frequency volume chart variables, and bladder capacity at hydrodistension were compared.

RESULTS

HL-IC patients were older and had higher OSSI/OSPI scores, greater daytime frequency and nocturia, reduced maximum and average voided volumes, and smaller bladder capacity at hydrodistension compared with BPS patients. Pain intensity and illness duration were comparable among the three groups. HL-IC patients had autoimmune disorders as comorbidities more often, but had psychiatric disorders and irritable bowel syndrome less often compared with BPS patients. No discernible differences in clinical characteristics of symptom severity and comorbid disorders were evident between BPS patients with and without glomerulations.

CONCLUSIONS

The presence of HL is associated with distinctive clinical characteristics, while glomerulations are not in female patients with IC/BPS. The presence of HL, but not glomerulations, is a robust phenotypic feature of IC/BPS in women.

Phenotypes of BPS/IC

Purpose of Review

The aim of this review is to summarise the latest research related to different phenotypes of BPS/IC, addressing the evidence for current well-defined phenotypes as well as identifying novel potential phenotypes and highlighting areas for future study.

Recent Findings

Two distinct phenotypes of BPS/IC are well-recognised: Hunner’s lesion disease and non-Hunner’s lesion BPS/IC. Recent studies have shown these phenotypes exhibit distinct clinical, pathological and cystoscopic features, and targeted treatment to Hunner’s lesions can prove effective. Recent studies have also identified new potential phenotypes based on biochemical, molecular and histological markers, pathophysiological mechanisms of disease, clinical features, cystoscopic findings, radiological features and urodynamic factors. This evidence has improved our understanding of the underlying mechanism of disease and may enable more personalised and targeted therapy in the future.

Summary

Novel phenotypes of BPS/IC relate to the presence of certain biomarkers, alterations in the urinary microbiome, the characteristics of pain and presence of co-existing somatic and psychosocial conditions, altered patterns of brain white matter changes and urodynamic features. Further study is required to evaluate whether these potential phenotypes are clinically useful based on their ability to guide treatment selection and predict outcome from therapy, and therefore optimise therapeutic outcomes.

Phenotyping of interstitial cystitis/bladder pain syndrome

Interstitial cystitis/bladder pain syndrome is a chronic, potentially debilitating condition characterized by pain perceived to be related to the bladder in conjunction with lower urinary tract symptoms, and includes a wide variety of clinical phenotypes with diverse etiologies. Currently the only clinically relevant proven phenotype of interstitial cystitis/bladder pain syndrome is the Hunner lesion. Whether the presence of Hunner lesions is a hallmark of a distinct disease cohort or a potentially transient feature of non-Hunner lesion phenotype has been debated but remains controversial. There are few documented examples of a patient converting between the two forms. Growing clinical and basic evidence supports eliminating the Hunner lesion phenotype from the bladder pain syndrome umbrella and considering it a distinct disease. The Hunner lesion phenotype is characterized by distinct bladder histology, including subepithelial chronic inflammatory changes and epithelial denudation, and specific clinical characteristics (older onset age, severe bladder-centric symptoms, reduced bladder capacity, and favorable response to the lesion-targeted therapies). To define the Hunner lesion phenotype, it is necessary to develop an atlas of standardized images of cystoscopic (and, if possible, pathological) appearances of Hunner lesions. A true potential and clinically relevant phenotype of interstitial cystitis/bladder pain syndrome may be patients with non-bladder-centric symptoms, characterized by the affect dysregulation and somatic symptoms, and a greater bladder capacity in absence of Hunner lesions. In the present workshop, we concluded that the Hunner lesion is a valid phenotype and can reasonably be considered a disease in its own right. Assessment of bladder capacity and the extent of symptoms (bladder beyond or bladder centric) may help phenotyping of interstitial cystitis/bladder pain syndrome. Proper phenotyping is essential for the diagnosis and treatment of interstitial cystitis/bladder pain syndrome, and for facilitating research.

Urine cytokines as biomarkers for diagnosing interstitial cystitis/bladder pain syndrome and mapping its clinical characteristics

The objective of the present study was to investigate the diagnostic values of urine cytokines in patients with interstitial cystitis/bladder pain syndrome (IC/BPS) and to identify their correlations with clinical characteristics. Urine samples were collected from 127 patients with IC/BPS [European Society for the Study of Interstitial Cystitis (ESSIC) types 1 and 2] and 28 controls. Commercially available multiplex immunoassays (MILLIPLEX map kits) were used to analyze 31 targeted cytokines. Cytokine levels between patients with IC/BPS and controls were analyzed using ANOVA. Receiver-operating characteristic curves of each cytokine to distinguish IC/BPS from controls were generated for calculation of the area under the curve. Patients with IC/BPS had urine cytokine profiles that differed from those of controls. Between patients with ESSIC type 1 and 2 IC/BPS, urine cytokine profiles were also different. Among cytokines with high diagnostic values (i.e., area under the curve > 0.7) with respect to distinguish patients with ESSIC type 2 IC/BPS from controls, regulated upon activation, normal T cell expressed and presumably secreted (RANTES), macrophage inflammatory protein (MIP)-1β, and IL-8 were of higher sensitivity, whereas macrophage chemoattractant protein (MCP)-1, chemokine (C-X-C motif) ligand 10 (CXCL10), and eotaxin-1 were of higher specificity. In multivariate logistic regression models controlling for age, sex, body mass index, and diabetes mellitus, the urine cytokines with high diagnostic values (MCP-1, RANTES, CXCL10, IL-7, and eotaxin-1) remained statistically significant in differentiating IC/BPS and controls. MCP-1, CXCL10, eotaxin-1, and RANTES were positively correlated with glomerulation grade and negatively correlated with maximal bladder capacity. In conclusion, patients with IC/BPS had urine cytokine profiles that clearly differed from those of controls. Urine cytokines might be useful as biomarkers for diagnosing IC/BPS and mapping its clinical characteristics.

Bladder Hydrodistention Does Not Result in a Significant Change in Bladder Capacity for Interstitial Cystitis/Bladder Pain Syndrome Patients

OBJECTIVE

To assess the impact of multiple (2 or more) bladder hydrodistentions (HODs) on anesthetic bladder capacity (BC) in a large cohort of interstitial cystitis/bladder pain syndrome (IC/BPS) patients. Urinary HOD under anesthesia is a third line therapeutic approach used to treat patients with IC/BPS. There is some concern that performing multiple therapeutic HODs may be contraindicated due to the potential for contributing to a diminished BC over time.

MATERIALS AND METHODS

This is a retrospective chart review of IC/BPS patients from a single institution who had undergone 2 or more bladder HOD procedures. Patient demographic and clinical data, including BC under anesthesia, were retrieved from patient charts for analysis. Least squares regression slopes of BC under anesthesia were calculated and used to estimate within-patient BC changes over time.

RESULTS

Data from 168 patients (637 HOD procedures) were included for analysis. The average change in BC, 0.52 ± 8.33 mL/mo, was not significantly different from 0 (P= .42). Linear regression analyses did not identify any significant correlation between BC over time with: (1) age, (2) number of HODs, (3) frequency of HODs, (4) average BC, (5) length of time with an IC/BPS diagnosis, or (6) length of time during which the patient's BC was evaluated. Moreover, there was no difference in BC change over time in patients with and without Hunner's lesion (P = .86).

CONCLUSION

Multiple therapeutic HODs, over several years, do not result in a significant change in BC in IC/BPS patients.

Histological evidence supports low anesthetic bladder capacity as a marker of a bladder-centric disease subtype in interstitial cystitis/bladder pain syndrome

INTRODUCTION AND HYPOTHESIS

Low anesthetic bladder capacity has been shown to be a biomarker for bladder-centric interstitial cystitis/bladder pain syndrome (IC/BPS). The goal of this study was to determine if histopathological evidence from bladder biopsies supports anesthetic bladder capacity (BC) as a marker to distinguish a bladder-centric IC/BPS subtype.

METHODS

From a review of our large IC/BPS cohort of patients undergoing hydrodistention, we identified a total of 41 patients with low BC (≤ 400 ml); an additional 41 consecutive patients with BC > 400 ml were selected as the comparator group. The original bladder mucosal biopsy pathology slides were re-reviewed by a single pathologist (blinded to patient information) using a standardized grading scale developed for this study.

RESULTS

Histologically, the low BC subjects exhibited higher levels of acute inflammation (p = 0.0299), chronic inflammation (p = 0.0139), and erosion on microscopy (p = 0.0155); however, there was no significant difference in mast cell count between groups (p = 0.4431). There was no significant gender difference between the groups; female patients were the majority in both groups (low BC: 94.12%, non-low BC: 100%; p = 0.1246). Individuals in the low BC group were older (p < 0.0001), had a higher incidence of Hunner's lesions on cystoscopy (p < 0.0001), and had significantly higher scores, i.e., more bother symptoms, on two IC/BPS questionnaires (ICPI, p = 0.0154; ICSI, p = 0.0005).

CONCLUSIONS

IC/BPS patients with low anesthetic bladder capacity have histological evidence of significantly more acute and chronic inflammation compared with patients with a non-low bladder capacity. These data provide additional evidence to support low bladder capacity as a marker of a distinct bladder-centric IC/BPS phenotype.

Small fiber polyneuropathy as a potential therapeutic target in interstitial cystitis/bladder pain syndrome

INTRODUCTION AND HYPOTHESIS

Interstitial cystitis/bladder pain syndrome (IC/BPS) and fibromyalgia (FM) are frequently co-occurring medical diagnoses in patients referred to the urology clinic for secondary and tertiary treatment options.

METHODS

Abundant literature has shown that many patients with FM have small fiber polyneuropathy (SFPN) that can be confirmed via skin punch biopsy and immunological staining to measure nerve density.

RESULTS AND CONCLUSIONS

This finding of SFPN provides a therapeutic target for FM and in this article we hypothesize and provide rationale for the idea that this same phenomenon (SFPN) might explain, in some IC/BPS patients, the finding of widespread pain and likewise provide a therapeutic target for these patients.

Recent advances in imaging and understanding interstitial cystitis

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating condition associated with intense pelvic pain and bladder storage symptoms. Since diagnosis is difficult, prevalence estimates vary with the methodology used. There is also a lack of proven imaging tools and biomarkers to assist in differentiation of IC/BPS from other urinary disorders (overactive bladder, vulvodynia, endometriosis, and prostatitis). Current uncertainty regarding the etiology and pathology of IC/BPS ultimately impacts its timely and successful treatment, as well as hampers future drug development. This review will cover recent developments in imaging methods, such as magnetic resonance imaging, that advance the understanding of IC/BPS and guide drug development.

Prodrome and Non-prodrome Phenotypes of Bladder Pain Syndrome/Interstitial Cystitis

OBJECTIVE

To test the hypothesis that risk factors for bladder pain syndrome/interstitial cystitis (BPS/IC) in women differ between those with and without the BPS/IC prodrome.

MATERIALS AND METHODS

Incident cases of BPS/IC and healthy controls were recruited nationally. More than half the BPS/IC cases reported subsyndromal urinary symptoms for decades before onset of BPS/IC and were identified as having the prodrome. Risk factors for BPS/IC were examined separately for cases with and without the prodrome using a set of matched controls.

RESULTS

Two risk factors distinguished 178 prodrome from 134 non-prodrome cases. One was "UTIs" in the year before BPS/IC onset, possibly a manifestation of the prodrome itself. The other was the presence of the maximal number of nonbladder syndromes (NBSs): prodrome cases were 12 times more likely than non-prodrome cases to have ≥4 NBSs. Additional risk factors for prodrome and/or non-prodrome cases were the direct association of exogenous female hormones, as well as 3 inverse associations: type 2 diabetes mellitus, multiple pregnancies, and current daily smoking.

CONCLUSION

Prodrome cases developed urinary symptoms in their early 20s (ie, the prodrome) and were at very high risk of numerous NBSs. Non-prodrome cases developed urinary symptoms in their early 40s (ie, full-blown BPS/IC) and were no more likely than controls to have the maximal number of NBSs. These findings are consistent with recent suggestions of two BPS/IC phenotypes: one with systemic and psychosocial manifestations and the other more specific to the bladder. Additionally, several risk factors identified here might be hints of related or causal nervous system pathophysiologies.

Novel contrast mixture achieves contrast resolution of human bladder wall suitable for T1 mapping: applications in interstitial cystitis and beyond

PURPOSE

Instillation of novel contrast mixture (NCM) was recently shown to improve the contrast resolution of rat bladder wall with high contrast-to-noise ratio (CNR). Here, the clinical safety and the feasibility of NCM-enhanced MRI to achieve artifact-free visualization of human bladder wall suitable for quantitative measurement of the magnetic resonance (MR) longitudinal relaxation time (T1) was assessed.

METHODS

Six female subjects [two controls and two with Hunner-type interstitial cystitis IC and two with non-Hunner-type IC] consented for MRI at 3 T before and after instillation of NCM [4 mM gadobutrol and 5 mM ferumoxytol in 50 mL of sterile water for injection]. Single breath-hold fast MR acquisition in large readout bandwidth for 5-mm-thick single slice with variable flip angle was applied to minimize the motion and chemical shift artifacts in measurements of bladder wall thickness (BWT), CNR and T1 from 20 pixels.

RESULTS

NCM instillation in subjects did not evoke pain or discomfort. Fourfold increase in bladder wall CNR (*p < 0.02) and pixel size of 0.35 mm with minimal influence of artifacts allowed accurate determination of bladder wall thinning ~ 0.46 mm from 50 mL NCM (*p < 0.05). Pre-contrast bladder wall T1 of 1544 ± 34.2 ms was shortened to 860.09 ± 13.95 ms in Hunner-type IC (*p < 0.0001) relative to only 1257.42 ± 20.59 and 1258.16 ± 6.16 ms in non-Hunner-type IC and controls, respectively.

CONCLUSION

Findings demonstrate the safety and feasibility of NCM-enhanced MRI to achieve artifact-free differential contrast and spatial resolution of human bladder wall, which is suitable for measuring BWT and pixel-wise measurement of T1 in post-contrast setting.

Impact of Cystectomy With Urinary Diversion Upon Tracked Receipt of Opioid Prescriptions Among Patients With Interstitial Cystitis/Bladder Pain Syndrome

OBJECTIVE

To compare opioid requirements before and after cystectomy for end-stage Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) using a statewide tracking system.

METHODS

Narcotic prescriptions were captured using the North Carolina Controlled Substance Reporting System for patients at a single institute undergoing cystectomy with urinary diversion (CWUD) for refractory, end-stage IC/BPS between 2010 and 2017. Values were documented for the year before and the year after surgery (excluding 30 days postoperatively to account for surgical pain) and converted to morphine equivalents (ME). Values were compared using Student t test.

RESULTS

Following CWUD, there was a mean decrease in opioid receipt per patient of 6535 ME/year (P = .321). 8/26 (31%) had not filled any opiate prescriptions for the preceding 3 months at time of manuscript writing.

CONCLUSION

In certain patients with end-stage, refractory IC/BPS, CWUD can help reduce opioid requirements.

Alexithymia and anesthetic bladder capacity in interstitial cystitis/bladder pain syndrome

OBJECTIVE

In contrast to the inconsistent results of organic causes, it has been found that psychological risk factors are reliably related to functional somatic syndromes (FSSs), including interstitial cystitis/bladder pain syndrome (IC/BPS). Compared to patients with acute cystitis, a subgroup of IC/BPS patients with a history of childhood relational trauma reported intensified unregulated affective states (i.e., anxiety and depression) and trauma-related psychopathology (i.e., dissociation). Nevertheless, it remains unknown whether psychosocial risk factors can be separated from bladder-centric factors. This study aimed to verify whether psychosocial factors such as alexithymia, which is a key psychological factor of FSSs, are less likely to be linked to a low bladder capacity in patients with IC/BPS.

METHODS

Ninety-four female IC/BPS patients were recruited from the outpatient departments of urology, obstetrics, and gynecology. Anxiety, depression, dissociation, childhood relational trauma, and alexithymia were assessed using standardized scales, and anesthetic bladder capacity was examined by cystoscopic hydrodistention.

RESULTS

Positive correlations were found between anesthetic bladder capacity and the psychosocial variables, including alexithymia. An increased bladder capacity was associated with anxiety, dissociation, and childhood relational trauma, and a combination of high cognitive and low affective alexithymia mediated the correlations between bladder capacity and the psychosocial variables.

CONCLUSIONS

Psychosocial variables that are associated with an aversive childhood relational environment and affect dysregulation may constitute a pathogenic trajectory that differs from bladder-centric defects such as a lower bladder capacity. The findings of this study support the notion that IC/BPS in some patients may be due to an FSS.