Vulvodynia

CHAPTER 27 Vulvodynia

Vulvodynia is defined as chronic burning, stinging, irritation, soreness, rawness, stabbing, or other painful sensations of the vulva in the absence of any clinical or laboratory abnormalities that could account for the discomfort. Itching is not a typical symptom.

Epidemiology and clinical manifestations

Vulvodynia is an extremely common condition. Several surveys report that approximately 10–16% of women have experienced unexplained chronic vulvar pain at some point in their life, and about 4–7% of women experienced unexplained discomfort at the time of surveys ¹^–³. Vulvodynia occurs in Caucasians and African women at similar rates, and may be increased in women of Hispanic background¹. The incidence in Asians is unknown. It generally occurs after the teenage years.

Patients typically present with pain with intercourse. Most women report that any touch or pressure to the vulva, including tight clothes, wiping, tampon insertion, and sexual activity, produces pain. Some women have pain only with touch, whereas others have pain that is only worsened by touch, or an occasional patient experiences pain that is completely independent of touch or pressure. Pain ranges from mild, annoying discomfort to severe pain that precludes activities of daily living, including exercising, sexual activity, and sometimes even sitting.

Most patients believe that chronic yeast infections or bacterial vaginosis are the cause of their burning. Although these infections may have occurred, they are nearly always coincidental, and patients rarely report that symptoms completely remit, even briefly, with treatment. As a result, some women are convinced that they have resistant infections, and believe that they may have a compromised immune system.

By definition, the physical examination of women with vulvodynia shows no specific cause for pain. Mild erythema is sometimes present, and patients usually indicate the vulvar vestibule as the area of greatest discomfort. Many women, however, experience pain that extends beyond the vestibule at least at times, and some patients report discomfort involving the labia majora and even the perineum and perianal skin.

Pressing on the vulva with a cotton-tipped applicator usually elicits pain in the vestibule, sometimes with discomfort that extends beyond that area. An occasional person reports no pain with cotton-tipped applicator pressure despite background, constant vulvar burning or pain.

Often, women with vulvodynia exhibit coincidental abnormalities such as Candida albicans, irritant contact dermatitis, bacterial vaginosis, or other abnormalities, but these are insufficiently severe to produce the degree of discomfort. When these factors are corrected, and the discomfort remains, a diagnosis of vulvodynia is confirmed.

Vulvodynia has been classified into different subsets depending upon location of pain and the presence of spontaneous pain (unprovoked) versus pain only to touch or irritants (provoked). The significance of these subsets lies in the possibility of different etiologies for different patterns; the importance of standardizing terminology so that research evaluates like populations; and the fact that surgical therapy is only appropriate for very localized forms of vulvodynia. The International Society for the Study of Vulvovaginal Disease has clarified and redefined the classification and terminology of vulvar pain vulvodynia and subsets ⁴. This new classification divides causes of pain into that produced by specific disorders and vulvodynia, and further divides vulvodynia according to location and the presence or absence of pain with touch, friction, pressure, urine, or other usually nonpainful stimuli (Box 27.1).

From a practical standpoint, patients with vulvodynia most often fall into one of two major patterns. First, and most common, is that of vestibulodynia (formerly called vulvar vestibulitis, vulvar vestibulitis syndrome, vestibular adenitis, and infection of the minor vestibular glands). These patients tend to be premenopausal and report pain with touch in the vestibule, including sexual activity, constricting clothing, tampon use, and bicycle-riding. Nonspecific erythema within the vestibule is sometimes present (Figure 27.1). The other primary pattern is that of generalized vulvodynia, where discomfort is either generalized or migratory, and generally reported to be independent of touch. Unfortunately, few studies carefully characterize patients with vulvodynia sufficiently to validate the separation of two or more subsets, and this author and others do not find these to be easily separable subsets^5,⁶. Most patients exhibit symptoms that exist on a spectrum, with considerable overlap, suggesting that vestibulodynia and generalized vulvodynia are variants of the same process.

Figure 27.1 Vestibulodynia (vulvar vestibulitis) is characterized by pain to touch in the vestibule, sometimes associated with redness that is often localized to the ostia of vestibular glands just external to the hymeneal caruncles.

Often, patients report comorbid conditions, including interstitial cystitis, chronic constipation or irritable bowel syndrome, fibromyalgia, headaches, temporomandibular joint syndrome, low-back pain, depression, anxiety, premenstrual syndrome, sleep disorders, multiple medication “allergies,” and low energy levels ⁷.

Diagnosis and differential diagnosis

The differential diagnosis of vulvodynia includes any cause of vulvovaginal pain. Vulvar pain can occur with infection, skin disease, and several specific neurologic diseases, such as pudendal neuralgia or postherpetic neuralgia. These causative conditions are usually easily identified with a history and a careful physical examination. Most common infections are unlikely causes of chronic pain; bacterial vaginosis more often produces discharge and odor, whereas C. albicans usually causes itching. However, more subtle or unusual presentations of infection in skin disease must be ruled out. Bacterial vaginitis (streptococcal or staphylococcal) and non-albicans Candida infection (such as C. glabrata or C. krusei) are occasional causes of vulvovaginal pain. Specific skin diseases that produce erosions or ulcerations cause pain; most common are lichen planus, and secondarily scratched or eroded lichen sclerosus and lichen simplex chronicus. More subtle are dermatoses of the vaginal epithelium, which result in irritating vaginal secretions that produce an irritant contact dermatitis of the vestibule. These dermatoses include desquamative inflammatory vaginitis as well as erosive dermatoses such as lichen planus and the much less common cicatricial pemphigoid and pemphigus vulgaris.

Specific neuropathic pain syndromes mimic vulvodynia: diabetic neuropathy, postherpetic neuralgia (which occurs following herpes zoster virus infection rather than herpes simplex virus infection); and pudendal neuralgia ⁸. At times, nerve root compression from a protruding disk, or central nervous system diseases such as multiple sclerosis, cause pain, but these are generally not localized to the vulva.

The diagnosis of vulvodynia can be made largely by history, with the majority of women self-reporting chronic burning or irritation ultimately receiving a diagnosis of vulvodynia ⁹. However, in order to avoid missing the occasional patient with an easily correctable cause of pain, these conditions must be ruled in or out by a careful physical examination, routine vaginal cultures, and the careful evaluation of a wet amount of vaginal secretions for both infectious organisms and inflammation. Neuropathic pain syndromes can be more difficult to rule out, although a history and physical examination to include a local neurologic examination usually help to identify specific, definable neurologic causes of pain.

Even when abnormalities are identified and corrected, factors such as C. albicans, irritant contact dermatitis, and mild vaginal inflammation are often found to be merely coincidental and not causative.