ABSTRACT: Vulvodynia (VVD) is a chronic pain disorder wherein women display sensitivity to evoked stimuli at the vulva and/or spontaneous vulvar pain. Our previous work suggests generalized hyperalgesia in this population; however, little is known about central neurobiological factors that may influence pain in VVD. Here we investigated local (vulvar) and remote (thumb) pressure-evoked pain processing in 24 VVD patients compared to 13 age-matched, pain-free healthy controls (HCs). As a positive control we also examined thumb pressure pain in 24 fibromyalgia patients. The VVD and fibromyalgia patients displayed overlapping insular brain activations that were greater than HCs in response to thumb stimulation (P < .005 corrected). Compared to HCs, VVD participants displayed greater levels of activation during thumb stimulation within the insula, dorsal midcingulate, posterior cingulate, and thalamus (P < .005 corrected). Significant differences between VVD subgroups (primary versus secondary and provoked versus unprovoked) were seen within the posterior cingulate with thumb stimulation and within the precuneus region with vulvar stimulation (provoked versus unprovoked only). The augmented brain activation in VVD patients in response to a stimulus remote from the vulva suggests central neural pathology in this disorder. Moreover, differing central activity between VVD subgroups suggests heterogeneous pathologies within this diagnosis.The presence of augmented brain responses to pressure stimuli remote from the vulva was observed in vulvodynia patients. These findings may guide treatment decisions for better response, as brain mechanisms may be a factor in some VVD patients.
Project description:Provoked vestibulodynia, the most common form of vulvodynia (unexplained pain of the vulva), is a prevalent, idiopathic pain disorder associated with a history of recurrent candidiasis (yeast infections). It is characterized by vulvar allodynia (painful hypersensitivity to touch) and hyperinnervation. We tested whether repeated, localized exposure of the vulva to a common fungal pathogen can lead to the development of chronic pain. A subset of female mice subjected to recurrent Candida albicans infection developed mechanical allodynia localized to the vulva. The mice with allodynia also exhibited hyperinnervation with peptidergic nociceptor and sympathetic fibers (as indicated by increased protein gene product 9.5, calcitonin gene-related peptide, and vesicular monoamine transporter 2 immunoreactivity in the vaginal epithelium). Long-lasting behavioral allodynia in a subset of mice was also observed after a single, extended Candida infection, as well as after repeated vulvar (but not hind paw) inflammation induced with zymosan, a mixture of fungal antigens. The hypersensitivity and hyperinnervation were both present at least 3 weeks after the resolution of infection and inflammation. Our data show that infection can cause persistent pain long after its resolution and that recurrent yeast infection replicates important features of human provoked vulvodynia in the mouse.
Project description:<h4>Introduction</h4>Vulvodynia, vulvar pain syndrome, is defined as vulvar pain of at least a 3-month duration without a clear identifiable cause, which may have associated factor and the etiology and treatment of this challenging disease is still unclear. Dyspareunia is a relevant symptom of patients with vulvodynia. Vaginal microbiome has known an important role in local immune-inflammatory responses and it may be important pathogenic mechanism in vulvodynia.<h4>Aim</h4>The objective of this study was to investigate the association of vaginal microbiome and vulvodynia.<h4>Methods</h4>We analyzed the microbial compositions of the vestibule and vagina among women with clinically diagnosed vulvodynia (n = 22) and age-matched healthy controls (n = 22) without vulvodynia. The compositions of bacterial microbiomes were compared by pyrosequencing of the 16S rRNA.<h4>Main outcome measure</h4>Vaginal microbiome alpha and beta diversity were assessed using the Shannon diversity index and Heat map. Linear discriminant analysis effect size was used to find out marker for vulvodynia.<h4>Results</h4>There were no significant differences in the age, duration of marriage, history of gynecologic surgery, parity, and menopause status between cases and controls. A total of 1,661,934 high-quality pyrosequencing reads was obtained to evaluate bacterial diversity, and 50,246 unique sequences represented all phylotypes. The type and mean number of the genera were not different between cases and controls. However, the most predominant phyla of bacteria were significantly different between cases and controls. 3 phyla (Firmicutes, Actinobacteria, and Tenericutes) and 11 genera including Gardnerella, Ureaplasma, Achromobacter, Mycoplasma, and Bifidobacteria were significantly more prevalent in cases than in controls (P < .05). Linear discriminant analysis effect size analysis suggest the Bifidobacterium, Mycoplasma, and Fenollaria species can be potential markers for vulvodynia.<h4>Conclusion</h4>Our results suggest the differences in vaginal microbiome can be associated with the vulvodynia. Park SY, Lee ES, Lee SR, et al. Vaginal Microbiome Is Associated With Vulvodynia, Vulvar Pain Syndrome: A Case-Control Study. Sex Med 2021;9:100314.
Project description:<h4>Background</h4>Vulvodynia is defined as vulvar pain for at least 3 months without a clear cause. To the best of our knowledge, there are no trials investigating the effects of internet treatment using CBT (Cognitive behavioural therapy) treatment with Acceptance and Commitment Therapy (ACT) components for women with vulvodynia. The aim of this study is to examine the effects of such a guided internet-based intervention on provoked vulvar pain during the waiting period before clinical treatment.<h4>Methods</h4>We will randomise 52 patients to either guided internet-based intervention with CBT with (ACT) components or no intervention during the waiting period for treatment as usual. Online assessments are conducted at baseline, posttreatment, and at follow-up after 9 months. The primary outcome measure is provoked vulvar pain. Secondary outcomes are depression, anxiety, sexual function, and quality of life. Linear-mixed effect models will be used to assess the effect of the internet-based intervention on vulvar pain, pain acceptance, depression, anxiety, sexual function, and quality of life over time, by applying the intention-to-treat approach. Continuous data will be analysed with general linear models using intention-to-treat and also per protocol approaches to assess the effects of the intervention at different time points. Ordinal and binary data will be analysed with Mann Whitney's test, Fischer's exact test and multivariate logistic regression, respectively.<h4>Discussion</h4>As a randomised controlled trial with short- and long-term follow-up points, the EMBLA study intends to provide a novel and better understanding regarding the treatment of vulvodynia and the role of internet-based treatment as a complement to standard care for women suffering from vulvodynia. The effects of vulvodynia on pain, sexual function, quality of life, depression, and anxiety are investigated. The study's results are expected to be of value in the planning of clinical care in the medical area. High dropout rates and technical difficulties associated with using the platform are common in similar studies.<h4>Trial registration number</h4>NCT02809612.
Project description:The interplay among pain, allergy and dysregulated inflammation promises to yield significant conceptual advances in immunology and chronic pain. Hapten-mediated contact hypersensitivity reactions are used to model skin allergies in rodents but have not been utilized to study associated changes in pain perception in the affected skin. Here we characterized changes in mechanical hyperalgesia in oxazolone-sensitized female mice challenged with single and repeated labiar skin exposure to oxazolone. Female mice were sensitized with topical oxazolone on their flanks and challenged 1-3 times on the labia. We then measured mechanical sensitivity of the vulvar region with an electronic pressure meter and evaluated expression of inflammatory genes, leukocyte influx and levels of innervation in the labiar tissue. Oxazolone-sensitized mice developed vulvar mechanical hyperalgesia after a single labiar oxazolone challenge. Hyperalgesia lasted up to 24 hours along with local influx of neutrophils, upregulation of inflammatory cytokine gene expression, and increased density of cutaneous labiar nerve fibers. Three daily oxazolone challenges produced vulvar mechanical hyperalgesic responses and increases in nerve density that were detectable up to 5 days post-challenge even after overt inflammation resolved. This persistent vulvar hyperalgesia is resonant with vulvodynia, an understudied chronic pain condition that is remarkably prevalent in 18-60 year-old women. An elevated risk for vulvodynia has been associated with a history of environmental allergies. Our pre-clinical model can be readily adapted to regimens of chronic exposures and long-term assessment of vulvar pain with and without concurrent inflammation to improve our understanding of mechanisms underlying subsets of vulvodynia and to develop new therapeutics for this condition.
Project description:Neuropathic vulvodynia is a state of vulval discomfort characterized by a burning sensation, diffuse pain, pruritus or rawness with an acute or chronic onset. Diabetes mellitus may cause this type of vulvar pain in several ways, so this study was conducted to evaluate streptozotocin-induced diabetes as a neuropathic pain model for vulvodynia in female rats. The presence of streptozotocin (50 mg/kg i.p.)-induced diabetes was initially verified by disclosure of pancreatic tissue degeneration, blood glucose elevation and body weight loss 5-29 days after a single treatment. Dynamic (shortened paw withdrawal latency to light brushing) and static (diminished von Frey filament threshold pressure) mechanical allodynia was then confirmed on the plantar foot surface. Subsequently, both static and dynamic vulvodynia was detected by application of the paradigm to the vulval region. Systemic gabapentin (75 mg/kg, i.p.) and topical gabapentin (10 % gel) were finally tested against allodynia and vulvodynia. Topical gabapentin and the control gel vehicle significantly increased paw withdrawal threshold in the case of the static allodynia model and also paw withdrawal latency in the model for dynamic allodynia when compared with the streptozotocin-pretreated group. Likewise, in the case of static and dynamic vulvodynia, there was a significant antivulvodynia effect of systemic and topical gabapentin treatment. These outcomes substantiate the value of this model not only for allodynia but also for vulvodynia, and this was corroborated by the findings not only with systemic but also with topical gabapentin.
Project description:A standardized tampon insertion and removal test, the Tampon Test provides an alternative to sexual intercourse pain as an outcome measure for vulvodynia research. We report upon the reliability, validity, and responsiveness to change of the Tampon Test as an outcome measure for vulvodynia clinical trials.Outcome measures were assessed in women enrolled in the Vulvar Vestibulitis Clinical Trial, a randomized clinical trial of oral desipramine and topical lidocaine effectiveness. Reliability estimates of the Tampon Test using the Kappa statistic evaluated week-to-week measures at baseline. Tampon Test construct and discriminant validity were assessed through correlation with other outcome measures. Patients' ability to regularly perform the Tampon Test was compared with regularity of reporting intercourse pain.During the 2-week baseline phase, women with vulvodynia reported stable mean Tampon Test scores 4.6+/-2.6 (week -2); 4.6+/-2.7 (week -1); and 4.7+/-2.8 (week 0) with moderate week-to-week reliability (weighted Kappa 0.52). Over an 8-week phase of trial intervention, change in the Tampon Test measure significantly correlated to a number of outcome measures, including daily pain (r=0.42), intercourse pain (r=0.35), cotton swab vestibular pain (r=0.38), and the Brief Pain Inventory (r=0.49). Women with vulvodynia study participants performed the Tampon Test 96.3% of the requested time, which was twofold higher adherence than intercourse pain measurement (49.7%).The Tampon Test reflects a real life experience that is reliable, with good construct validity as shown by the breadth of correlated outcome measures. The Tampon Test is an appropriate outcome measure for vulvodynia research that can be considered for use as the primary efficacy endpoint in clinical trials of treatments for vulvodynia.ClinicalTrials.gov, www.clinicaltrials.gov, NCT00276068II.
Project description:Vulvodynia is a chronic vulvar pain disorder and fibromyalgia is a chronic widespread musculoskeletal pain disorder, both of unknown etiology. Association of these conditions is well documented. Intravaginal algometer measurement of tenderness to pressure applied to the pelvic floor muscles helps define vulvodynia associated with musculoskeletal factors. Women with both vulvodynia and fibromyalgia might have increased pelvic muscle pain compared to women with vulvodynia alone, defining the possible link of these 2 conditions.We sought to: (1) correlate pain intensity during the nongenital tender point tenderness examination to pain intensity with the vaginal algometer in women with provoked vestibulodynia, and (2) determine whether subjects with provoked vestibulodynia and fibromyalgia had higher pain intensity scores with the vaginal algometer than those without fibromyalgia.In all, 92 subjects referred for vulvar pain were confirmed to have provoked vestibulodynia using the cotton swab test. A diagnosis of fibromyalgia was made if pain was present (numeric rating scale >1) in at least 11 sites of the 18-point nongenital tender point tenderness exam. Vaginal pain sensitivity was measured using an intravaginal pressure algometer, where 0.1, 0.3, and 0.5 kg/cm2 forces were applied digitally in random assignment by force and location to the right and left iliococcygeus muscle regions and the posterior vaginal wall. Both tender point tenderness and algometer pain intensity were reported on a 0 (no pain) to 10 (worse pain) numeric rating scale. Correlations were computed between the composite pain intensity (total of rating scale from each pressure threshold at specified site) of nongenital and those of iliococcygeus regions and the posterior vaginal wall. Independent t tests were used to determine differences in iliococcygeus regions and the posterior vaginal algometer pain ratings and presence or absence of fibromyalgia. The significance level was at P < .05. The data were expressed as mean ± SD.A significant correlation was found between numeric rating scale pain scores on the nongenital tender point tenderness exam and algometer testing on the iliococcygeus region (r = 0.44, P < .0001) and the posterior vaginal wall (r = 0.45, P < .0001). Subjects with fibromyalgia by tender point tenderness had significantly higher iliococcygeal pain (6.14 ± 2.07 vs 3.74 ± 2.22, P = .0001) and posterior vaginal wall pain (5.67 ± 2.10 vs 3.07 ± 2.16, P < .0001) than women without fibromyalgia by tender point tenderness.Women with provoked vestibulodynia who experience more severe pain with nongenital tender point palpation also experience more deep vaginal pain on pelvic exam. Those who fulfill the diagnosis of fibromyalgia show significantly more intense deep vaginal pain to palpation of iliococcygeus muscles and posterior vaginal wall. Further research using a more precise definition of fibromyalgia is necessary to confirm this relationship, but findings suggest that women with provoked vestibulodynia coexisting with fibromyalgia have greater risk of superimposed vaginal muscle pain and may be candidates for early adjunctive pelvic floor physical therapy. These findings need to be explored in women with generalized, nonprovoked vulvodynia.
Project description:Vulvodynia is a remarkably prevalent chronic pain condition of unknown etiology. An increase in numbers of vulvar mast cells often accompanies a clinical diagnosis of vulvodynia and a history of allergies amplifies the risk of developing this condition. We previously showed that repeated exposures to oxazolone dissolved in ethanol on the labiar skin of mice led to persistent genital sensitivity to pressure and a sustained increase in labiar mast cells. Here we sensitized female mice to the hapten dinitrofluorobenzene (DNFB) dissolved in saline on their flanks, and subsequently challenged them with the same hapten or saline vehicle alone for ten consecutive days either on labiar skin or in the vaginal canal. We evaluated tactile ano-genital sensitivity, and tissue inflammation at serial timepoints. DNFB-challenged mice developed significant, persistent tactile sensitivity. Allergic sites showed mast cell accumulation, infiltration of resident memory CD8<sup>+</sup>CD103<sup>+</sup> T cells, early, localized increases in eosinophils and neutrophils, and sustained elevation of serum Immunoglobulin E (IgE). Therapeutic intra-vaginal administration of ?<sup>9</sup>-tetrahydrocannabinol (THC) reduced mast cell accumulation and tactile sensitivity. Mast cell-targeted therapeutic strategies may therefore provide new ways to manage and treat vulvar pain potentially instigated by repeated allergenic exposures.
Project description:BACKGROUND:Sexual dysfunction is common in women with vulvodynia. OBJECTIVE:The purpose of this study was (1) to evaluate whether extended-release gabapentin is more effective than placebo in improving sexual function in women with provoked vulvodynia and whether there is a relationship between treatment outcome and pelvic pain muscle severity that is evaluated by palpation with standardized applied pressure and (2) to evaluate whether sexual function in women with provoked vulvodynia would approach that of control subjects who report no vulvar pain either before or after treatment. STUDY DESIGN:As a secondary outcome in a multicenter double-blind, randomized crossover trial, sexual function that was measured by the Female Sexual Function Index was evaluated with gabapentin (1200-3000 mg/d) compared with placebo. Pain-free control subjects, matched by age and race, also completed Female Sexual Function Index for comparison. RESULTS:From August 2012 to January 2016, 230 women were screened at 3 academic institutions, and 89 women were assigned randomly to treatment. Gabapentin was more effective than placebo in improving overall sexual function (adjusted mean difference, 1.3; 95% confidence interval, 0.4-2.2; P=.008), which included desire (mean difference, 0.2; 95% confidence interval, 0.0-3.3; P=.04), arousal (mean difference, 0.3; 95% confidence interval, 0.1-0.5; P=.004), and satisfaction (mean difference, 0.3; 95% confidence interval, 0.04-0.5; P=.02); however, sexual function remained significantly lower than in 56 matched vulvodynia pain-free control subjects. There was a moderate treatment effect among participants with baseline pelvic muscle pain severity scores above the median on the full Female Sexual Function Index scale (mean difference, 1.6; 95% confidence interval, 0.3-2.8; P=.02) and arousal (mean difference, 0.3; 95% confidence interval, 0.1-0.6; P=.01) and pain domains (mean difference, 0.4; 95% confidence interval, 0.02-0.9; P=.04). CONCLUSION:Gabapentin improved sexual function in this group of women with provoked vulvodynia, although overall sexual function remained lower than women without the disorder. The most statistically significant increase was in the arousal domain of the Female Sexual Function Index that suggested a central mechanism of response. Women with median algometer pain scores >5 improved sexual function overall, but the improvement was more frequent than the pain domain. We hypothesize that gabapentin may be effective as a pharmacologic treatment for those women with provoked vulvodynia and increased pelvic muscle pain on examination.
Project description:Vulvar dermatology represents a challenge for many providers. Given that the vulva is both a gynecologic and dermatologic organ, patients with cutaneous lesions involving the vulva may present to primary care, gynecology, or dermatology. Particularly within dermatology, the vulva remains understudied, which can lead to anxiety among providers regarding appropriate next steps in the diagnosis and management of vulvar lesions. Thus, the purpose of this review is to highlight commonly encountered anatomic variants and benign neoplasms of the vulva, distinguish them from key pathologic mimickers, and provide guidance to practicing dermatologists on what may constitute normal vulvar variations.