Small Fiber Polyneuropathy May Be a Nexus Between Autonomic Nervous System Dysregulation and Pain in Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a highly heterogeneous chronic and debilitating condition which effects millions of women and men in the United States. While primarily defined by urinary symptoms and pain perceived to be emanating from the bladder, IC/BPS patients frequently have co-occurring conditions and symptoms, many of which affect diverse body systems related to autonomic nervous system function. The impact on the autonomic system appears to stem from increased sympathetic innervation of the urinary tract, along with increased systemic sympathetic tone and decreased parasympathetic tone. Concurrent with these findings is evidence for destruction of peripheral sympathetic innervation to the sweat glands which may relate to small fiber polyneuropathy. It is unknown to what degree the wider alterations in autonomic function are also related to destruction/alterations in the small fibers carrying autonomic innervation. This potential nexus is an important point of investigation to better understand the unclarified pathophysiology of interstitial cystitis/bladder pain syndrome, the numerous co-occurring symptoms and syndromes, and for the identification of novel targeted therapeutic strategies.

Pelvic Floor Myofascial Pain Might Influence Treatment Outcome of Interstitial Cystitis/bladder Pain Syndrome

IntroductionIn patients with interstitial cystitis or bladder pain syndrome (IC/BPS), 85% were found to have pelvic floor myofascial pain (PFMP) and hypertonicity (PFH). However, they are not typically trained to consider or assess PFMP as a contributing factor to patients’ IC/BPS symptoms. This study aimed to explore the relationship between PFMP and treatment outcomes in women with IC/BPS.MethodsPatients with IC/BPS who received any type of treatment were prospectively enrolled. They underwent vaginal digital examination at baseline. PFMP severity was quantified on the visual analog scale (VAS). Subject assessment items included O’Leary-Sant symptom score (OSS), Global Response Assessment (GRA), and Beck’s anxiety inventory. Object assessment items included bladder computed tomography (CT), urodynamic parameters, maximum bladder capacity, and grade of glomerulation.ResultsA total of 65 women with IC/BPS (mean age, 57.1 ± 11.3 years) were enrolled in the study. Patients with more severe PFMP had significantly higher rate of dyspareunia (p = .031); more comorbidities (p = .010); higher number of PFMP sites (p < .001); and higher OSS (p = .012). PFMP severity was not significantly correlated with bladder conditions, whether subjective or objective. Moreover, PFMP severity (VAS) was significantly negatively associated with GRA score.ConclusionPFMP might affect the subjective results of IC/BPS treatment but not the bladder condition. Therefore, in the future treatment of patients with IC/BPS, digital vaginal examinations of pelvic floor muscles should be performed and focused more on the PFM-related conditions, and necessary PFM treatments, such as the vaginal pelvic floor muscle message, should be scheduled.

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.

Erratum: Chondroitin Sulfate and Hyaluronic Acid Perfusion for Interstitial Cystitis/Bladder Pain Syndrome: A Systematic Review and Meta-Analysis

Paper link corrected: https://bonoi.org/index.php/si/article/view/636 It has been brought to authors attention that there is a missing part in “Materials and Methods” of the Systematic Review article by Xiao et al., entitled “Chondroitin Sulfate and Hyaluronic Acid Perfusion for Interstitial Cystitis/Bladder Pain Syndrome: A Systematic Review and Meta-Analysis” in the Volume 39, No. 4 of Science Insights (pp.363-373). The missing part of the “Materials and Methods” is as below: Population: Patients with IC/BPS.Intervention: All patients underwent intravesical HA and/or CS treatment regimen.Comparison: Improvement in symptoms pre-treatment and post-treatment or other treatment regimen.Outcome: The primary outcome was the change in visual analogue scale (VAS) for pain symptom from baseline to the follow-up period; secondary outcomes were the changes in total scores of the O’Leary-Sant Interstitial Cystitis Symptom Index (ICSI) and Problem Index (ICPI), storage symptoms including frequency and urgency, and bladder capacity.

Components of the Endogenous Cannabinoid System as Potential Biomarkers for Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition causing bladder pressure and pain. The condition is of unknown etiology and is often accompanied by other symptoms, including chronic pelvic pain, increased urinary urgency, and frequency. There is no definitive diagnosis for IC/BPS, and treatment options are currently limited to physical therapy and medications to help alleviate symptoms. The endogenous cannabinoid system (ECS) is an important regulator of numerous physiological systems, including the urinary system. Modulations of the ECS have been shown to be beneficial for IC/BPS-associated pain and inflammation in rodents. As an attempt to identify potential biomarkers for IC/BPS, we reviewed experimental studies where the components of the ECS have been quantified in experimental models of IC/BPS. Further investigations using well-defined animal models and patients’ data are required to obtain stronger evidence regarding the potential for ECS components to be definitive biomarkers for IC/BPS.