Similarities between interstitial cystitis/bladder pain syndrome and vulvodynia: implications for patient management

The association between vulvodynia and interstitial cystitis/bladder pain syndrome: A systematic review

BACKGROUND

Vulvodynia (VVD) is a debilitating chronic vulvar pain significantly affecting patients' quality of life. Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic and complex illness characterized by an unpleasant sensation related to the filling of the bladder and it strongly impacts patients' lives. The exact mechanisms of the two syndromes remain unknown, but there is an overlap between suspected pathophysiologies.

OBJECTIVE

To present an overview of the current research on the association between VVD and IC/BPS.

SEARCH STRATEGY

A systematic search of three electronic databases was conducted. Studies examining the correlation between VVD and IC/BPS with male and female patients aged over 18 years were included.

SELECTION CRITERIA

Studies assessing the coexistence of VVD and IC/BPS were included. Reviews, letters to the editor, conference abstracts, book chapters, guidelines, Cochrane reviews, and expert opinions were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers screened the studies for eligibility. Eligible studies were screened for quality.

MAIN RESULTS

A total of 13 studies were included in the final review. Among them, 11 presented a positive association between the two syndromes. The studies highlighted that VVD and IC/BPS share common comorbidities and possibly etiopathogenic pathways.

CONCLUSION

VVD and IC/BPS are both complex and multifactorial syndromes. This review highlights an association between them, but additional studies on the topic should be conducted for a more precise conclusion.

Efficacy of Two Laser Treatment Strategies for Breast Cancer Survivors With Genitourinary Syndrome of Menopause

Background A typical symptom of patients with genitourinary syndrome of menopause (GSM) is dyspareunia. Dyspareunia has been thought to be caused by vaginal dryness. In recent years, a survey of breast cancer survivors (BCS) with GSM has shown that para-hymen is the most painful. Dyspareunia and superficial vulvar pain (vulvodynia) may be closely linked. A recent study showed that vulvodynia is very common in BCS. Therefore, we believe treatment targeting the vagina and the vulva is necessary for pain in BCS with GSM. We hypothesized that treating both the vagina and the vulva would solve the problem of BCS with GSM. We compared the vaginal erbium SMOOTH mode laser (VEL) and neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser (VEL+Nd:YAG) combination treatment over time. This study explores therapeutic targets for pain in BCS with GSM. Methodology This retrospective, case-control study targeted sexually active BCS who reported GSM with vulvodynia and dyspareunia. After all women enrolled in the VEL treatment group had completed treatment, we treated women enrolled in the VEL+Nd:YAG treatment group. A total of 256 women who received either VEL+Nd:YAG or VEL were enrolled. Propensity score (PS)-matching analysis was used to compare two-year postoperative data retrospectively. The PS-matching results registered 102 patients in the VEL+Nd:YAG group and 102 patients in the VEL group. Symptoms were assessed using the visual analog scale (VAS) for vulvodynia before and after laser treatment for one, three, six, 12, and 24 months after completion. As a preliminary study, the vulvodynia swab test confirmed the causative location of dyspareunia. Moreover, the Female Sexual Function Index (FSFI) and Vaginal Health Index Score (VHIS) were assessed. FSFI and VHIS were treated as supplement research because the conditions were unmet. Results In the vulvodynia swab test, dyspareunia, and para-hymen (especially at 4 o'clock and 9 o'clock), all felt pain, and only a few felt pain in the vagina and labia. FSFI improved significantly in the VEL+Nd:YAG group and persisted for two years. VHIS improved equally in both groups and was not significantly different. After the first laser application, the VEL+Nd:YAG and the VEL groups showed sustained efficacy and safety in vulvodynia. Baseline VAS scores (8.74 ± 0.72 vs. 8.79 ± 0.74; p = 0.564) were similar in both groups. Both groups had a significant (p < 0.001) decrease in the VAS score. The VAS values in the VEL+Nd:YAG group and the VEL group decreased from the pretreatment to 3.79 ± 0.63 (p < 0.001 vs. baseline) and 5.56 ± 0.89 (p < 0.001 vs. baseline) after the third treatments, respectively. After 24 months, the VAS value in the VEL+Nd:YAG group and the VEL group was at 4.43 ± 1.38 (p < 0.001 vs. baseline) and 5.56 ± 0.89 (p < 0.001 vs. baseline), respectively. The side effects in both groups were short-term and minor. Conclusions Both VEL+NdYAG and VEL effectively and safely treat GSM dyspareunia and vulvodynia in BCS. Comparing the two groups, we confirmed that VEL+Nd:YAG treatment of the vaginal vestibule and vaginal opening reduced superficial vulvar pain more effectively, extensively, and over a longer period than VEL. The results of the vulvodynia swab test, FSFI, and VHIS suggest that the vulva and the vagina are important therapeutic targets for pain in BCS with GSM. The importance of treating the vulvar area for superficial pain and dyspareunia in GSM has been emphasized.

Inflammation-Independent Antinociceptive Effects of DF2755A, a CXCR1/2 Selective Inhibitor: A New Potential Therapeutic Treatment for Peripheral Neuropathy Associated to Non-Ulcerative Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a chronic bladder disease of unknown etiology characterized by urinary frequency and episodic and chronic pain. Analgesic treatments for IC/BPS are limited, especially for patients with non-Hunner (non-ulcerative) type IC who usually have poor overall outcomes. Here, we demonstrate that oral treatment with DF2755A, a potent and selective inhibitor of chemokine receptors CXCR1/2, can prevent and reverse peripheral neuropathy associated to non-Hunner IC/BPS by directly inhibiting chemokine-induced excitation of sensory neurons. We tested DF2755A antinociceptive effects in a cyclophosphamide (CYP)-induced non-ulcerative IC rat model characterized by severe peripheral neuropathy in the absence of bladder inflammatory infiltrate, urothelial hyperplasia, and hemorrhage. Treatment with DF2755A prevented the onset of peripheral neuropathy and reversed its development in CYP-induced IC rats, showing a strong and long-lasting anti-hyperalgesic effect. Ex vivo and in vitro studies showed that DF2755A treatment strongly inhibited the expression of CXCR2 agonists, CXCL1/KC, and CXCL5 and of transient receptor potential vanilloid 1 (TRPV1) compared to vehicle, suggesting that its effects can be due to the inhibition of the nociceptive signaling passing through the CXCL1/CXCR1-2 axis and TRPV1. In conclusion, our results highlight the key pathophysiological role played by the CXCL1/CXCR1-2 axis and TRPV1 in the onset and development of peripheral neuropathy in non-Hunner IC and propose DF2755A as a potential therapeutic approach for the treatment of not only inflammatory painful conditions but also neuropathic ones and in particular non-Hunner IC/BPS.

Organ cross-sensitization mechanisms in chronic diseases related to the genitourinary tract

There are various refractory chronic inflammatory diseases related to the genitourinary tract, such as interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome. It has been reported that in the general population, these diseases are related to other chronic illnesses, such as irritable bowel syndrome or vulvodynia. Herein, we review papers regarding pelvic organ cross-sensitization, a factor which is considered to contribute to these relationships. Several other researchers and ourselves have reported that noxious stimuli from a diseased pelvic organ are transmitted to an adjacent normal structure via shared sensory neural pathways at the prespinal, spinal, and supraspinal levels, resulting in functional changes in the adjacent normal structure. In conclusion, since there are few treatments to cure interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome completely, further studies regarding organ cross-sensitization may provide new insights into the pathophysiology and treatment strategies for these diseases.

The short-term efficacy of intravesical instillation of hyaluronic acid treatment for bladder pain syndrome/interstitial cystitis

OBJECTIVE

The aim of the study was to evaluate the short term efficacy of intravesical instillation of hyaluronic acid in patients with Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC).

MATERIAL AND METHODS

The study included 54 women with BPS/IC who received intravesical instillation of hyaluronic acid treatment (120 mg/50 mL) for 6 weeks. Visual Analogue Scale (VAS), The O'Leary Sant Questionnaire (ICSI/ICPI) forms of the patients were filled by the clinician and the health technician separately before and 3 months after the treatment. Demographic characteristics of the patients were recorded, and effectiveness of the treatment was investigated according to these data.

RESULTS

Decrease in mean VAS and mean total scores of ICSI and ICPI was observed after three months of intravesical instillation of hyaluronic acid treatment (55%, p<0.05 and 48.5%, p<0.05 and 45.5%, p<0.05, respectively). In most of the patients, all scores of VAS, ICSI and ICPI improved (minimum: 75.9%, maximum: 94.4%). Mostly the symptoms of nocturia and pollakiuria were seen, and treated after the instillation treatment.

CONCLUSION

It has been observed that in the short-term follow-up of intravesical instillation of hyaluronic acid treatment, the symptoms have highly improved. Also, Turkish versions of ICSI and ICPI forms were reliable and comprehensible.

Animal Modelling of Interstitial Cystitis/Bladder Pain Syndrome

The etiology of interstitial cystitis/bladder pain syndrome (IC/BPS) remains elusive and may involve multiple causes. To better understand its pathophysiology, many efforts have been made to create IC/BPS models. Most existing models of IC/BPS strive to recreate bladder-related features by applying noxious intravesical or systemic stimuli to healthy animals. These models are useful to help understand various mechanisms; however, they are limited to demonstrating how the bladder and nervous system respond to noxious stimuli, and are not representative of the complex interactions and pathophysiology of IC/BPS. To study the various factors that may be relevant for IC/BPS, at least 3 different types of animal models are commonly used: (1) bladder-centric models, (2) models with complex mechanisms, and (3) psychological and physical stressors/natural disease models. It is obvious that all aspects of the human disease cannot be mimicked by a single model. It may be the case that several models, each contributing to a piece of the puzzle, are required to recreate a reasonable picture of the pathophysiology and time course of the disease(s) diagnosed as IC/BPS, and thus to identify reasonable targets for treatment.