Increased innervation of the vulval vestibule in patients with vulvodynia

Psychological treatment for vaginal pain: does etiology matter? A systematic review and meta-analysis

INTRODUCTION

Classification of vaginal pain within medical or psychiatric diagnostic systems draws mainly on the presumed presence or absence (respectively) of underlying medical etiology. A focus on the experience of pain, rather than etiology, emphasizes common ground in the aims of treatment to improve pain and sexual, emotional, and cognitive experience. Thus, exploring how vaginal pain conditions with varying etiology respond to psychological treatment could cast light on the extent to which they are the same or distinct.

AIM

To examine the combined and relative efficacy of psychological treatments for vaginal pain conditions.

METHODS

A systematic search of EMBASE, MEDLINE, PsycINFO, and CINAHL was undertaken. Eleven randomized controlled trials were entered into a meta-analysis, and standardized mean differences and odds ratios were calculated. Effect sizes for individual psychological trial arms were also calculated.

MAIN OUTCOME MEASURES

Main outcome measures were pain and sexual function.

RESULTS

Equivalent effects were found for psychological and medical treatments. Effect sizes for psychological treatment arms were comparable across vaginal pain conditions.

CONCLUSIONS

Effectiveness was equivalent regardless of presumed medical or psychiatric etiology, indicating that presumed etiology may not be helpful in selecting treatment. Research recommendations and clinical implications are discussed.

Vulvodynia

Vulvodynia is a complex disorder reported by up to 16% of women in the general population. While most patients describe it as burning, stinging, irritation, or rawness, it is underreported and underrecognized by providers. Vulvodynia is costly both economically and psychologically due to its negative impact on quality of life. Vulvodynia is a diagnosis of exclusion with unknown etiology and may involve multiple sources of pain in the same woman. Thus, there are no clinical or histopathologic criteria for the diagnosis other than consideration and careful evaluation to exclude other causes of pain. Successful therapy often requires a multidisciplinary approach with more than one therapeutic intervention to address the physical, psychological, psychosexual, and relationship components.

Immunohistochemical analysis of neuropeptides (protein gene product 9.5, substance P and calcitonin gene-related peptide) in hypertrophic burn scar with pain and itching

BACKGROUND

Neuropeptides have been recently reported as having an important role in wound repair, and relief from pain and itching sensation. The aim of this study was to evaluate the effect of neuropeptides on the wound healing process in hypertrophic scar formation that accompanies severe pain and itching sensation.

METHODS

We collected forty-three hypertrophic scar specimens from hypertrophic scar release and skin graft under general anesthesia. Immunohistochemical stains for protein gene product (PGP) 9.5, substance P (SP), and calcitonin gene-related peptide (CGRP) were performed. Pain and itching over the scar were recorded using verbal numerical rating scale (VNRS).

RESULTS

In the epidermis, PGP 9.5, SP, and CGRP were significantly increased in hypertrophic scars compared with matched unburned skin. In the reticular dermis, SP and CGRP were significantly increased in hypertrophic scars compared with control. The pain and itching verbal numerical rating scale in scar group were significantly higher compared to control. In the papillary dermis, the PGP represented significant correlation with Itching P (correlation coefficient 0.698) and the SP represented significant correlation with pain N (correlation coefficient -0.671). In the reticular dermis, the SP represented significant correlation with pain N (correlation coefficient -0.614) and CGRP represented significant correlation with pain P/Itching P (correlation coefficient 0.801/0.611).

CONCLUSIONS

Neuropeptides such as PGP 9.5, SP, and CGRP seem to affect scarring via sensory neurotransmission, it have a regulatory role for pain and itching sensation in hypertrophic scars.

Pain Symptoms in Fibromyalgia Patients with and without Provoked Vulvodynia

Objective. The aim of the study was to compare the pain symptoms of fibromyalgia patients exhibiting (FMS+PVD) and not exhibiting (FMS) comorbidity with provoked vulvodynia. Study Design. The case control study was performed in 39 patients who had been diagnosed with FMS and accepted to undergo gynaecological examination and in 36 healthy women (C). All patients completed standardized questionnaires for pain intensity, pain area, and psychological functioning. The gynaecological examination included vulvar pain pressure reactivity (Q-tip), pelvic tone assessment (Kegel manoeuver), and a semistructured interview collecting detailed information about pelvic symptoms and sexual function. Results. FMS+PVD patients displayed a higher number of associated symptoms than FMS patients. The vulvar excitability was significantly higher in FMS+PVD than in FMS and in both groups than in Controls. Half of FMS+PVD patients were positive to Kegel manoeuver and displayed higher scores in widespread pain intensity, STAI-Y2, and CESD levels than Kegel negative patients. Conclusions. The study reveals that increased vulvar pain excitability may occur in FMS patients independently of the presence of coital pain. Results suggest that coital pain develops in patients with higher FMS symptoms severity due to the cooperative effects of peripheral and central sensitization mechanisms.

Histopathologic characteristics of menopausal vestibulodynia

OBJECTIVE

To assess whether premenopausal and postmenopausal vestibulodynia have different histologic features.

METHODS

We conducted a retrospective analysis of vestibulectomy specimens from 21 women with postmenopausal vestibulodynia and compared them with 88 premenopausal patients (42 primary, 46 secondary). Women with primary vestibulodynia experienced pain at first introital touch and women with secondary vestibulodynia experienced pain after an interval of painless intercourse. Clinical records established the type of vestibulodynia, duration of symptoms, and hormone status. Tissues were stained for inflammation, nerves, mast cells, estrogen receptor α, and progesterone receptor. Histologic findings in the postmenopausal patients were compared with primary and secondary premenopausal patients using proportional odds logistic regression and analysis of variance.

RESULTS

Seventy-one percent (15/21) of postmenopausal women reported vestibular dyspareunia related to a drop in estrogen either with menopause (13/21) or previously, postpartum (2/21). Eighty-six percent (18/21) of postmenopausal patients were using local or systemic estrogen but pain persisted. Compared with premenopausal primary and secondary vestibular biopsies, postmenopausal tissues had more lymphocytes (unadjusted odds ratio [OR] 9.0, 95% confidence interval [CI] 2.8-33.3; adjusted OR for parity and duration of symptoms 9.1, 95% CI 2.6-31.9; unadjusted OR 6.2, 95% CI 1.9-20.0; adjusted OR 6.6, 95% CI 2.0-21.9, respectively) and mast cells (mean 36 compared with 28 and 36 compared with 26, respectively). There was significantly less neural hyperplasia and progesterone receptor expression in postmenopausal biopsies compared with primary cases but less progesterone receptor and similar neural hyperplasia compared with premenopausal secondary cases. Estrogen receptor α did not vary among groups.

CONCLUSION

Premenopausal and postmenopausal vestibulodynia share histologic features of neurogenic inflammation but differ strikingly in degree. When estrogen supplement does not alleviate symptoms of postmenopausal dyspareunia, vestibulodynia should be considered.

LEVEL OF EVIDENCE

: II.

Trophic factor and hormonal regulation of neurite outgrowth in sensory neuron-like 50B11 cells

Sensory axon integrity and regenerative capacity are important considerations in understanding neuropathological conditions characterized by hyper- or insensitivity. However, our knowledge of mechanisms regulating axon outgrowth are limited by an absence of suitable high-throughput assay systems. The 50B11 cell line generated from rat embryonic dorsal root ganglion neurons offers a promising model for screening assays. Prior characterization shows that these cells express cytoskeletal proteins and genes encoding ion channels and neurotrophin receptors in common with sensory nociceptor neurons. In the present study we further characterized 50B11 cells in regard to their phenotypes and responsiveness to neurotrophic and hormonal factors. 50B11 cells express neuronal cytoplasmic proteins including beta-3 tubulin, peripherin (a marker of unmyelinated neurons), and the pan-neuronal ubiquitin hydrolase, PGP9.5. Only PGP9.5 immunoreactivity was uniformly distributed throughout soma and axons, and therefore presents the best means for visualizing the entire axon arbor. All cells co-express both NGF and GDNF receptors and addition of ligands increased neurite length. 50B11 cells also showed immunoreactivity for the estrogen receptor-α and the angiotensin receptor type II, and both 17-β estradiol and angiotensin II increased outgrowth by differentiated cells. 50B11 cells therefore show features reported previously for primary unmyelinated nociceptor neurons, including responsiveness to classical neurotrophins and hormonal modulators. Coupled with their ease of culture and predictable differentiation, 50B11 cells represent a promising cell line on which to base assays that more clearly reveal mechanisms regulating axon outgrowth and integrity.

Dynamic mechanical allodynia following finger amputation: Unexpected skin hyperinnervation

The development of chronic pain after amputations is not an uncommon event. In some cases the most disabling problem is represented by the symptom called dynamic mechanical allodynia, characterized by the painful sensation evoked by gently stroking the skin. Despite the growing interest in understanding pain mechanisms, little is known about the mechanism sustaining this peculiar type of pain. We present here the case of a 53-year-old female patient who complained of severe tactile allodynia in the hand after amputation of her left second finger, resistant to several medical and surgical treatments. In order to gain information about the pain mechanism, two neurodiagnostic skin biopsies were obtained from the area of tactile allodynia and from the contralateral, normal skin area. Skin biopsies showed an unexpected increased innervation of the allodynic skin compared to the contralateral, normal skin area (+ 80.1%). Hyperinnervation has been proposed as a mechanism of pain following nerve lesions, but the increased innervation described here could be also attributed to neuronal plasticity occurring in chronic inflammatory conditions. Independently from the uncertain cause of the epidermal hyperinnervation, in this patient we tried to reduce the elevated number of epidermal nerve fibres by treating the skin with topical capsaicin (0.075%) three times a day, and obtained a persistent pain relief. In conclusion, neurodiagnostic skin biopsy might represent an useful tool for detecting derangements of epidermal innervation in patients with dynamic mechanical allodynia and can help to select an individually tailored therapeutic strategy in such difficult clinical conditions. Further studies are needed to clarify this issue and try to gain better understanding of chronic pain mechanisms in patients who underwent finger amputation.

Angiotensin II receptor type 2 activation is required for cutaneous sensory hyperinnervation and hypersensitivity in a rat hind paw model of inflammatory pain

Many pain syndromes are associated with abnormal proliferation of peripheral sensory fibers. We showed previously that angiotensin II, acting through its type 2 receptor (AT2), stimulates axon outgrowth by cultured dorsal root ganglion neurons. In this study, we assessed whether AT2 mediates nociceptor hyperinnervation in the rodent hind paw model of inflammatory pain. Plantar injection of complete Freund's adjuvant (CFA), but not saline, produced marked thermal and mechanical hypersensitivity through 7 days. This was accompanied by proliferation of dermal and epidermal PGP9.5-immunoreactive (ir) and calcitonin gene-related peptide-immunoreactive (CGRP-ir) axons, and dermal axons immunoreactive for GFRα2 but not tyrosine hydroxylase or neurofilament H. Continuous infusion of the AT2 antagonist PD123319 beginning with CFA injection completely prevented hyperinnervation as well as hypersensitivity over a 7-day period. A single PD123319 injection 7 days after CFA also reversed thermal hypersensitivity and partially reversed mechanical hypersensitivity 3 hours later, without affecting cutaneous innervation. Angiotensin II-synthesizing proteins renin and angiotensinogen were largely absent after saline but abundant in T cells and macrophages in CFA-injected paws with or without PD123319. Thus, emigrant cells at the site of inflammation apparently establish a renin-angiotensin system, and AT2 activation elicits nociceptor sprouting and heightened thermal and mechanical sensitivity.

PERSPECTIVE

Short-term AT2 activation is a potent contributor to thermal hypersensitivity, whereas long-term effects (such as hyperinnervation) also contribute to mechanical hypersensitivity. Pharmacologic blockade of AT2 signaling represents a potential therapeutic strategy aimed at biologic mechanisms underlying chronic inflammatory pain.

A Psychological View of Sexual Pain among Women: Applying the Fear-Avoidance Model

Aim: The purpose of this paper is to examine how well research findings on dyspareunia (intercourse pain) fit the fear-avoidance (FA) model on pain. Results: The evidence suggests that the experience of pain in dyspareunia functions similarly to the pain reported in other pain conditions. There are also accumulating data showing that the central mechanisms of the FA model, such as catastrophizing, fear, hypervigilance and disability, are central to the experience of sexual pain. However, there are also some potential differences between sexual pain and other pain conditions that demand further attention in terms of the role of the partner, specific emotional consequences of avoidance and the effect of hypervigilance on sexual arousal. Conclusion: The results demonstrate the relevance of the FA model in sexual pain. They also imply that treatment methods for fear and avoidance in other pain conditions offer new avenues for treating sexual pain problems in the clinic. Future studies should focus on expanding how the mechanisms in the FA model contribute to sexual pain, as well as how treatments based on the model may be applied clinically.

Bone morphogenetic protein 4 mediates estrogen-regulated sensory axon plasticity in the adult female reproductive tract

Peripheral axons are structurally plastic even in the adult, and altered axon density is implicated in many disorders and pain syndromes. However, mechanisms responsible for peripheral axon remodeling are poorly understood. Physiological plasticity is characteristic of the female reproductive tract: vaginal sensory innervation density is low under high estrogen conditions, such as term pregnancy, whereas density is high in low-estrogen conditions, such as menopause. We exploited this system in rats to identify factors responsible for adult peripheral neuroplasticity. Calcitonin gene-related peptide-immunoreactive sensory innervation is distributed primarily within the vaginal submucosa. Submucosal smooth muscle cells express bone morphogenetic protein 4 (BMP4). With low estrogen, BMP4 expression was elevated, indicating negative regulation by this hormone. Vaginal smooth muscle cells induced robust neurite outgrowth by cocultured dorsal root ganglion neurons, which was prevented by neutralizing BMP4 with noggin or anti-BMP4. Estrogen also prevented axon outgrowth, and this was reversed by exogenous BMP4. Nuclear accumulation of phosphorylated Smad1, a primary transcription factor for BMP4 signaling, was high in vagina-projecting sensory neurons after ovariectomy and reduced by estrogen. BMP4 regulation of innervation was confirmed in vivo using lentiviral transduction to overexpress BMP4 in an estrogen-independent manner. Submucosal regions with high virally induced BMP4 expression had high innervation density despite elevated estrogen. These findings show that BMP4, an important factor in early nervous system development and regeneration after injury, is a critical mediator of adult physiological plasticity as well. Altered BMP4 expression may therefore contribute to sensory hyperinnervation, a hallmark of several pain disorders, including vulvodynia.

[Update on the diagnosis and treatment of vulvodynia]

CONTEXT

Vulvodynia is a complex and multifactorial clinical condition. It is defined as chronic vulvar discomfort characterized by burning, stinging or irritation. Its diagnostic difficulty and treatment is known.

OBJECTIVES

To review the medical literature of the last 10 years from a critical point of view.

EVIDENCE ACQUISITION

A search was made in Medline/Pubmed and the Cochrane Library using the terms vulvodynia and vestibulodynia to which etiology, epidemiology, diagnosis, neurophysiological test and treatment or management, were added.

EVIDENCE SYNTHESIS

In spite of the advances achieved in all of the aspects of vulvodynia, the methodology used at present in many cases does not have the desirable statistical soundness: there are few control or placebo-controlled groups and double-blind studies. Uniformity is lacking in the scales, indexes and questionnaires for the correct evaluation of pain before and after the treatment and debatable diagnostic criteria are use. The limited use of neurophysiological diagnostic resources that validate the clinical findings has been observed in the studies analyzed. In most of the works, the medical treatments have been shown to be ineffective. Physiotherapy and cognitive-behavioral therapy seem to be promising therapeutic tools. Surgery (vestibulectomy) stands out by its demonstrated efficacy in the publications studied.

CONCLUSIONS

A multidisciplinary approach is always necessary. Topical medical, psychological and physical therapy treatments may have sum effects and become an alternative to surgery. New pathways of research and more regulated studies are required.

Sensory and sympathetic nerve fibers undergo sprouting and neuroma formation in the painful arthritic joint of geriatric mice

Introduction

Although the prevalence of arthritis dramatically increases with age, the great majority of preclinical studies concerning the mechanisms that drive arthritic joint pain have been performed in young animals. One mechanism hypothesized to contribute to arthritic pain is ectopic nerve sprouting; however, neuroplasticity is generally thought to be greater in young versus old nerves. Here we explore whether sensory and sympathetic nerve fibers can undergo a significant ectopic nerve remodeling in the painful arthritic knee joint of geriatric mice.

Methods

Vehicle (saline) or complete Freund's adjuvant (CFA) was injected into the knee joint of 27- to 29-month-old female mice. Pain behaviors, macrophage infiltration, neovascularization, and the sprouting of sensory and sympathetic nerve fibers were then assessed 28 days later, when significant knee-joint pain was present. Knee joints were processed for immunohistochemistry by using antibodies raised against CD68 (monocytes/macrophages), PECAM (endothelial cells), calcitonin gene-related peptide (CGRP; sensory nerve fibers), neurofilament 200 kDa (NF200; sensory nerve fibers), tyrosine hydroxylase (TH; sympathetic nerve fibers), and growth-associated protein 43 (GAP43; nerve fibers undergoing sprouting).

Results

At 4 weeks after initial injection, CFA-injected mice displayed robust pain-related behaviors (which included flinching, guarding, impaired limb use, and reduced weight bearing), whereas animals injected with vehicle alone displayed no significant pain-related behaviors. Similarly, in the CFA-injected knee joint, but not in the vehicle-injected knee joint, a remarkable increase was noted in the number of CD68⁺ macrophages, density of PECAM⁺ blood vessels, and density and formation of neuroma-like structures by CGRP⁺, NF200⁺, and TH⁺ nerve fibers in the synovium and periosteum.

Conclusions

Sensory and sympathetic nerve fibers that innervate the aged knee joint clearly maintain the capacity for robust nerve sprouting and formation of neuroma-like structures after inflammation/injury. Understanding the factors that drive this neuroplasticity, whether this pathologic reorganization of nerve fibers contributes to chronic joint pain, and how the phenotype of sensory and sympathetic nerves changes with age may provide pharmacologic insight and targets for better controlling aging-related joint pain.

Increased vanilloid receptor VR1 innervation in vulvodynia

Vulvodynia is characterised by painful burning sensation, allodynia and hyperalgesia in the region of the vulval vestibulus. While in many patients the cause of vulvodynia remains uncertain, we and others have previously shown increased intraepithelial and papillary innervation in vulvodynia. The vanilloid receptor VR1 (TRPV1) is expressed by nociceptors, and is triggered by capsaicin, noxious heat, protons, and chemicals produced during inflammation. In the present study we show increased papillary VR1 fibres by immunostaining and image analysis in vulvodynia tissues compared to controls (p<0.002). VR1 expression was found to be significantly increased when the percentage area immunostained was expressed as a ratio of VR1 to PGP 9.5, a pan-neuronal marker (P=0.01). VR1-positive fine epidermal fibres also appeared to be increased in vulvodynia tissues, by inspection. Fibres immunoreactive to the voltage-gated sodium channel SNS1/PN3 (Nav1.8), also expressed by nociceptors, were relatively scarce in both vulvodynia and control tissues. We hypothesize that increased expression of VR1 by nociceptors could mediate some of the symptoms in vulvodynia, for which systemic or topical specific VR1 antagonists may provide novel treatment.

Differences in primary compared with secondary vestibulodynia by immunohistochemistry

OBJECTIVE

To assess whether primary and secondary vestibulodynia represent different pathologic pathways.

METHODS

This was an analysis of archived vestibulectomy specimens from 88 premenopausal women with vestibulodynia (2002-2008). Patient records were reviewed to classify the type of vestibulodynia, duration of symptoms, and hormone status. Histologic sections were stained for hematoxylin and eosin to grade inflammation, S100 to highlight nerves, CD117 for mast cells, estrogen receptor α, and progesterone receptor. Differences between primary and secondary vestibulodynia were tested by t tests, chi-square analysis, and linear and logistic regression.

RESULTS

Primary vestibulodynia showed significant neural hypertrophy and hyperplasia (P=.02, adjusted odds ratio [OR] 3.01, 95% confidence interval [CI] 1.2-7.6) and increased progesterone receptor nuclear immunostaining (P=.004, adjusted OR 3.94, CI 1.6-9.9) compared with secondary vestibulodynia. Estrogen receptor α expression was also greater in primary vestibulodynia when symptom diagnosis was less than 5 years (P=.004, adjusted OR 5.53 CI 1.71-17.91).

CONCLUSION

Primary and secondary vestibulodynia have significantly different histologic features, suggesting that they may have separate mechanistic pathways. Clinically, this may mean the discovery of distinct conditions.

Hypersensitivity and hyperinnervation of the rat hind paw following carrageenan-induced inflammation

Studies of human tissue show that many chronic pain syndromes are accompanied by abnormal increases in numbers of peripheral sensory nerve fibers. It is not known if sensory nerve sprouting occurs as a result of inflammation present in these conditions, or other factors such as infection or extensive tissue damage. In the present study, we used a well established model of inflammation to examine cutaneous innervation density in relation to mechanical and thermal hypersensitivity. Adult female rats were ovariectomized to eliminate fluctuations in female reproductive hormones and one week later, a hind paw was injected with carrageenan or saline vehicle. Behavioral testing showed that saline vehicle injection did not alter thermal or mechanical thresholds compared to pre-injection baselines. Carrageenan injections resulted in markedly reduced paw withdrawal thresholds at 24 and 72 h after injection; this was accompanied by increased mechanical sensitivity of the contralateral paw at 72 h. Analysis of innervation density using PGP9.5 as a pan-neuronal marker at 72 h showed that inflammation resulted in a 2-fold increase in cutaneous innervation density. We conclude that inflammation alone is sufficient to induce sprouting of sensory cutaneous axon endings leading local tissue hyperinnervation, which may contribute to hypersensitivity that occurs in painful inflammatory conditions.

Histologic and receptor analysis of primary and secondary vestibulodynia and controls: a prospective study

OBJECTIVE

The objective of the study was to assess the association between hormone receptor densities, pain nerves, and inflammation in vestibulodynia patients.

STUDY DESIGN

In a prospective study, tender and nontender biopsies from 10 primary and 10 secondary vestibulodynia patients were compared with biopsies in 4 nontender controls. Hormone receptors were evaluated using immunohistochemistry for estrogen receptor-alpha and -beta, androgen, and progesterone receptors. Inflammation, nerves, and mast cells were assessed histologically. Statistical analysis was by Fisher's exact test, analysis of variance, paired Student t test, and Wilcoxon rank test.

RESULTS

Tender sites from primary vestibulodynia had increased nerve density compared with secondary and control biopsies (P = .01). Tender sites in secondary vestibulodynia had more lymphocytes than tender primary sites and control biopsies (P < .0001). Mast cells were increased in tender sites compared with nontender and controls. There were no differences in hormone receptor expression.

CONCLUSION

Markers of inflammation differed between primary and secondary vestibulodynia and controls.

Transcutaneous electrical nerve stimulation to treat vestibulodynia: a randomised controlled trial

OBJECTIVE

To assess the efficacy of transcutaneous electrical nerve stimulation (TENS) in the treatment of vestibulodynia.

DESIGN

Double-arm randomised placebo-controlled trial.

SETTING

An outpatient department for vulval disease.

POPULATION

Forty women with vestibulodynia, a vestibular discomfort mostly reported as a burning pain, occurring in the absence of relevant visible findings or a specific, clinically identifiable, neurological disorder.

METHODS

Twice a week active TENS or sham treatment were delivered through a vaginal probe via a calibrated dual channel YSY-EST device. Women of both groups underwent 20 treatment sessions.

MAIN OUTCOME MEASURES

Visual analogue scale (VAS), the short form of the McGill-Melzack Pain Questionnaire (SF-MPQ), the Marinoff Scale for dyspareunia and the Female Sexual Function Index questionnaire (FSFI) were assessed at baseline, at the end of treatment and at follow up 3 months after the end of treatment.

RESULTS

The VAS and SF-MPQ scores (6.2 +/- 1.9 and 19.5 +/- 11.9 before treatment, respectively) improved significantly in the active TENS group (2.1 +/- 2.7, P= 0.004 and 8.5 +/- 10.7, P= 0.001, respectively), but not in the placebo group. The Marinoff dyspareunia scale and the FSFI also showed a significant improvement.

CONCLUSIONS

TENS is a simple, effective and safe short-term (3 months) treatment for the management of vestibulodynia.

Skin biopsy for the diagnosis of peripheral neuropathy

Skin biopsy has become an accepted tool for investigating small nerve fibres, which are invisible to conventional neurophysiological tests even though they are affected early on in peripheral neuropathies of varying aetiology. Morphometric analysis of epidermal and dermal nerves has proved to be reliable, reproducible and unaffected by the severity of neuropathy, making skin biopsy useful for diagnosing small fibre neuropathy (SFN) in clinical practice. The possibility of obtaining skin biopsy specimens from different sites of the body, to repeat them within the area of the same sensory nerve, to distinguish between somatic and autonomic nerves and to investigate the expression of nerve-related proteins has widened the potential applications of this technique to clinical research. Skin biopsy performed using a minimally invasive disposable punch is a safe and painless procedure. Using specific antibodies with bright-field immunohistochemistry or immunofluorescence technique, it is possible to investigate unmyelinated fibres innervating the epidermis of hairy and glabrous skin, large myelinated fibres supplying specialized corpuscles in glabrous skin, and autonomic fibres innervating sweat glands, blood vessels and arrector pilorum muscles. This review discusses the features of skin innervation in hairy and glabrous skin, the functional properties of skin nerve fibres and their changes in peripheral neuropathies.

[Vulvar vestibulitis syndrome: a clinicopathological study of 14 cases]

BACKGROUND

Vulvar vestibulitis syndrome (VVS) is one of the most frequent causes of superficial dyspareunia in young women. VVS has a pronounced psychological impact. The results of pathological studies published thus far are controversial.

PATIENTS AND METHODS

Fourteen women with VVS were included in this study and underwent vestibular biopsy. Vulvar biopsies were taken from the orifice of Bartholin's gland. The biopsy samples were stained with a standard stain and PAS and 25 serial sections were prepared for each specimen.

RESULTS

The mean patient age was 26 years and VVS had been present for a mean 30 months. Extensive inflammation of mononuclear cells was observed in the vulvar chorionic epithelium. This inflammation was seen mainly around the minor vestibular glands. Mild exocytosis of lymphocytes was noted in the vestibular glands and ducts.

DISCUSSION

Most studies concerning this disease report chronic inflammation of the vulvar vestibular mucosa. This inflammation is seen mainly around the minor vestibular glands. We report the same pattern in our study. Moreover, we observed some exocytosis into the epithelium of minor vestibular glands and the excretory duct. This aspect has not been reported to date, further supporting the individual nature of this entity.

Insight into urogynecologic features of women with interstitial cystitis/painful bladder syndrome

OBJECTIVE

The prevalence of interstitial cystitis/painful bladder syndrome (IC/PBS) among gynecologic patients attending vulvar disease or pelvic pain clinics is higher than expected. The evaluation of gynecologic characteristics in patients with IC/PBS could be important to delineate a better therapeutic strategy.

METHODS

We compared clinical gynecologic characteristics including localized and generalized vulvodynia and sexual activity of 47 women with a definite diagnosis of IC/PBS versus 47 negative controls.

RESULTS

The prevalence of both generalized or localized vulvodynia was 85.1% (40 of 47) in the patients and 6.4% (3 of 47) in the control group (p<0.0001 by Fisher exact test). The mean visual analogue score on generalized or localized vulvodynia evaluated with the cotton swab test was 6.1+/-2.6 (SD) among women with IC/PBS and 0.6+/-1.7 in the control group (p<0.0001 with Mann-Whitney U test). Pain during intercourse was described as unbearable by 15 women with IC/PBS (31.9%) and 2 controls (4.3%; p=0.001 by Fisher exact test). Sexual function was significantly impaired in women with IC as measured by the median total score of the Female Sexual Function Index in comparison with controls (13.8 vs. 28.7; p<0.0001).

CONCLUSIONS

Patients with a definite diagnosis of IC/PBS appear to have a high risk of vulvodynia with the associated negative implications for sexual activity. The establishment of a multidisciplinary approach with the involvement of the gynecologist appears to be a logical requisite for a correct treatment strategy for these patients.

Skin biopsy as a diagnostic tool in peripheral neuropathy

Skin biopsy is a safe, minimally invasive, painless and cheap tool for providing diagnostic information on small nerve fibers, which are invisible to routine neurophysiological tests. Biopsy can be performed in hairy skin to investigate unmyelinated and thinly myelinated fibers and in glabrous skin to examine large myelinated fibers. Morphometric analysis of skin nerves is readily accomplished through the use of immunohistochemical techniques, and has proved to be reliable, reproducible and unaffected by the severity of neuropathy. One further advantage of skin biopsy over conventional nerve biopsy is that it allows somatic nerve fibers to be distinguished from autonomic nerve fibers. Morphological changes, axonal degeneration and abnormal regeneration occur in cutaneous nerves very early in the course of peripheral neuropathies, making skin biopsy a promising tool for investigating the progression of neuropathy and the effect of neuroprotective treatments in clinical practice and trials. This article reviews the techniques that are used to investigate the innervation of human skin, the possible uses of skin biopsy in diagnosing and monitoring peripheral neuropathies, and correlations between skin biopsy findings and those of other diagnostic methods.

Vulvodynia: case report and review of literature

Vulvodynia is defined as chronic vulvar burning, stinging, rawness, soreness or pain in the absence of objective clinical or laboratory findings to explain these symptoms. Vulvodynia is a chronic pain syndrome affecting up to 18% of the female population and is generally regarded as an underdiagnosed difficult to treat gynecological disorder. An increasing number of patients present with symptoms of vulvar pain, soreness, burning or irritation, which becomes chronic. Vulvodynia is a term used to describe chronic burning and/or pain in the vulva without objective clinical or laboratory findings to explain these symptoms. We present a case of vulvodynia accompanying somatoform disorder and depression.

Sensing the air around us: the voltage-gated-like ion channel family

Ion channels are a complex set of proteins having many important physiologic and potentially pathologic roles. The flow of ions through these channels and the subsequent cellular depolarization can trigger complex mechanisms such as cardiac rhythm, hormone secretion, and numerous sensory experiences. The transient receptor potential (TRP) channels are an important means for multiple organ systems to interact with their environment. The various TRP channel subfamilies respond to voltage or to ligands such as G-protein coupled receptors. Their ability to sense temperature, pain, stretch, and osmolarity among others enables them to mediate responses such as smooth muscle contraction, cough, or sensation of pain.

Sexual sequelae of general medical disorders

That sexual symptoms can signal serious underlying disease confirms the importance of sexual enquiry as an integral component of medical assessment. Data on sexual function are sparse in some medical specialties. However, increased scientific understanding of the central and peripheral physiology of sexual response could help to identify the pathophysiology of sexual dysfunction from disease and medical interventions, and also to ameliorate or prevent some dysfunctions. Many common general medical disorders have negative effects on desire, arousal, orgasm, ejaculation, and freedom from pain during sex. Chronic disease also interferes indirectly with sexual function, by altering relationships and self-image and causing fatigue, pain, disfigurement, and dependency. Current approaches to assessment of sexual dysfunction are based on models that combine psychological and biological aspects.

ORIGINAL RESEARCH—SURGERY: Surgical Treatment of Vulvar Vestibulitis Syndrome: Outcome Assessment Derived from a Postoperative Questionnaire

INTRODUCTION

Vulvar vestibulitis syndrome (VVS) is the most common pathology in women with sexual pain. Surgery for VVS was first described in 1981. Despite apparently high surgical success rates, most review articles suggest that surgery should be used only "as a last resort." Risks of complications such as bleeding, scarring, and recurrence of symptoms are often used to justify these cautionary statements. However, there are little data in the peer-reviewed literature to justify this cautionary statement.

AIMS

To determine patient satisfaction with vulvar vestibulectomy for VVS and the rate of complications with this procedure.

METHODS

Women who underwent a complete vulvar vestibulectomy with vaginal advancement by one of three different surgeons were contacted via telephone by an independent researcher between 12 and 72 months after surgery.

MAIN OUTCOME MEASURES

The primary outcome measurement of surgical success was overall patient satisfaction with surgery. Additional secondary outcome measurements included improvement in dyspareunia, changes in coital frequency, and occurrence of surgical complications.

RESULTS

In total, 134 women underwent surgery in a 5-year period. An independent research assistant was able to contact 106 women, and 104 agreed to participate in the study. Mean duration since surgery was 26 months. A total of 97 women (93%) were satisfied, or very satisfied, with the outcome of their surgery. Only three patients (3%) reported persistently worse symptoms after surgery and only seven (7%) reported permanent recurrence of any symptoms after surgery. Prior to surgery, 72% of the women were completely apareunic; however, after surgery, only 11% were unable to have intercourse.

DISCUSSION

In this cohort of patients, there was a high degree of satisfaction with surgery for VVS. In addition, the risks of complications with this procedure were low, and most complications were transient and the risk of recurrence after surgery was also found to be low.

Vulvodynia: a therapeutic challenge

Vulvodynia is a poorly understood, distressing and debilitating disorder. The management of this disorder remains insufficient and the lack of consistent terminology is confusing. The management of classic dysesthetic vulvodynia is fairly straightforward, using drugs effective against chronic neuropathic pain. However, vulvar vestibulitis syndrome remains a therapeutic challenge. A pragmatic approach is recommended for the management of patients with vulvar vestibulitis syndrome. In refractory cases, vestibulectomy has a high success rate, although the evidence is based mainly on small, descriptive studies. Comparative studies of conservative versus surgical management of vulvar vestibulitis syndrome are needed.

Recent developments in transient receptor potential vanilloid receptor 1 agonist-based therapies

Capsaicin and other naturally occurring pungent molecules have been used for centuries as topical analgesics and rubefactants to treat a variety of chronically painful conditions. Recently, instillations of high-concentration capsaicin and resiniferatoxin solutions have been found to be useful for the management of persistent bladder pain or overactive bladder. However, only within the last 7 years has it been appreciated that the selective action of these compounds on a subset of sensory nerve fibres is mediated by agonist activity at a ligand-gated ion channel called the transient receptor potential vanilloid receptor 1 (TRPV1). Accordingly, this discovery has fueled intensive research and drug development efforts, mainly in a search for novel analgesic or anti-inflammatory therapies. Two different, but non-mutually exclusive, strategies are being pursued: optimisation of TRPV1 agonist-based therapies, which can functionally inactivate nociceptive nerve fibres, and identification of receptor antagonists, which would prevent nociceptive fibres from being activated by ongoing inflammatory stimuli. Available information on TRPV1 agonists in development and their biological rationale will be summarised in this review.

Vulvar vestibulitis syndrome: A review

Vulvar vestibulitis syndrome (VVS) is a perplexing disease involving pain limited to the vulvar vestibule without objective clinical findings to explain the symptoms. The condition impairs sexual function and creates significant psychological distress. Its cause is unknown, and few randomized studies exist on the efficacy of interventions. This article reviews disease characteristics, possible etiologies, and approaches to management.

Cutaneous hypersensitivity to Candida albicans in idiopathic vulvodynia

We have observed that the majority of our vulvodynia patients give a previous history of vaginal candidiasis that was treated but was followed by symptoms of chronic vulvodynia. 27 vulvodynia patients were patch-tested to a standard series of contact allergens, a customized vulvar series and commensal organisms including ultraviolet-killed Candida albicans. Comparison tests for the commensal organism were made to a group of 13 female atopic dermatitis patients and to 19 female dermatitis patients without a history of childhood flexural dermatitis who were undergoing patch test evaluation in our clinic. Patients reporting vulvodynia were significantly (P < 0.05) more likely to react to C. albicans than the dermatitis comparison group. Interestingly, lower concentrations of C. albicans caused more positive patch tests than higher concentrations. Our findings suggest that previous C. albicans infection may predispose patients to a subsequent hypersensitivity response to C. albicans that is expressed only in areas of high cutaneous peripheral fibre density. Low levels of C. albicans may also be required to elicit this response as high levels of C. albicans may actually result in decreased cutaneous inflammation and decreased intensity of C. albicans patch test responses.

Neural correlates of painful genital touch in women with vulvar vestibulitis syndrome

Vulvar vestibulitis syndrome (VVS) is a common cause of dyspareunia in pre-menopausal women. Recent evidence points to the importance of the sensory component in VVS, particularly the heightened processing of tactile and pain sensation in the vulvar vestibule. The goal of the present study was to examine the neural basis of heightened sensitivity to touch (i.e. allodynia) in women with VVS. Using functional magnetic resonance imaging, we compared regions of neural activity in 14 women with VVS and 14 age- and contraceptive-matched control women in response to the application of mild and moderate pressure to the posterior portion of the vulvar vestibule. Intensity and unpleasantness ratings were recorded after each scan; these ratings were significantly higher for women with VVS than controls. All women with VVS described moderate pressure as painful and unpleasant, and 6 of the 14 women with VVS described mild pressure as painful and unpleasant. In contrast, none of the stimuli was painful for control women. Correspondingly, women with VVS showed more significant activations during pressure levels that they found to be either painful or non-painful than did controls during comparable pressure levels. During pressure described as painful by women with VVS, they had significantly higher activation levels in the insular and frontal cortical regions than did control women. These results suggest that women with VVS exhibit an augmentation of genital sensory processing, which is similar to that observed for a variety of syndromes causing hypersensitivity, including fibromyalgia, idiopathic back pain, irritable bowel syndrome, and neuropathic pain.