Inspection of the vulva is an essential part of a complete pelvic examination, and yet the area is often overlooked or given only a very cursory examination by clinicians.
For their part, patients can be confused by terminology and are often not aware of the difference between the vagina and the vulva when they are trying to report the location of a symptom or abnormality. A brief overview of the anatomy and diseases of the vulva may prove helpful for both clinicians and patients.
A review of normal vulvar anatomy is critical before moving on to a discussion of evaluation, diagnosis and biopsy. The vulva includes the mons pubis, labia majora, labia minora, clitoris and the vestibule. The most obvious feature of the vulva is hair that should cover the mons pubis and the labia majora.
Unfortunately, in our society, hair on the vulva is now being routinely removed by laser, waxing or shaving. Although hair on the vulva is deemed an unwanted and unnecessary feature, it serves a definite purpose, i.e., to protect the Skene’s and Bartholin’s glands from vaginal secretions, perspiration and contact irritants. Hair also plays a role in providing a cushion against impact during intercourse. Women should be informed of the purpose of hair during examinations.
The mons pubis comprises stratified squamous epithelium with a fat layer and lies over the pubic symphysis. The labia majora are two raised folds of adipose tissue that can be pigmented and bear hair. The labia are composed of stratified squamous epithelium, sebaceous glands and apocrine sweat glands. Fordyce spots are sebaceous glands on the medial aspect of the labia majora.¹ In postmenopausal women, loss of adipose tissue and hair from the mons pubis and labia is normal.
The labia minora, which lie within the labia majora and extend from the clitoris to the fourchette, are smooth and hairless. In some women, the labia minora can be covered by the labia majora, but in others, the labia minora protrude between the labia majora. The texture of the labia minora is highly individualized, and the color varies from shades of pink to brown.
The medial aspects of the labia minora join to form the clitoral hood, which covers the glans clitoris and provides protection for it. The glans is the receptor of sexual stimuli and responds by increasing in size. In some women, the clitoral hood retracts easily, but in others, it is adhered to the glans itself and cannot be pulled back. Either finding is normal.
The area between the labia minora is the vestibule, which contains the urethral meatus, Skene glands, vaginal introitus, and Bartholin glands. Remnants of the hymenal ring are seen around the margins of the introitus. Hart’s line marks the lower edge of the vestibule. The minor glands found throughout the vestibule become more evident in postmenopausal women.1
Consistency is key
When performing a vulvar examination, it is important to be consistent. By being consistent, the clinician will improve his or her ability to perform a thorough assessment and to identify any abnormalities. A vulvar examination begins with inspection of the vulvar tissues and the vestibule. Note any structural abnormalities, lesions or changes (including changes in pigmentation) on the mons, labia majora and labia minora and within the vestibule.
Once the vulva has been assessed, introduce the speculum into the vagina. Repeat the steps, looking for lesions and structural and pigmentary changes. When establishing a differential diagnosis for the presumed abnormality, start with basic vulvar changes, such as normal variants and infections, and move up in level of complexity to inflammatory conditions and neoplasia.
Diseases of the vulva
A common normal variant that is often misdiagnosed is papillomatosis, which is characterized by papillary growth of the vestibular mucosa located within Hart’s line. These growths are often misidentified as condylomas arising from infections with the human papillomavirus (HPV). Inappropriate treatment of the papillomas as condylomas can lead to acute or chronic symptoms of burning or pain in the vulva and the vestibule.
Contact or allergic vulvitis is very common following exposure to irritants. As many as 54% of symptomatic women turn out to have contact vulvitis.² Vulvitis resulting from contact with an irritant is more common than allergic vulvitis. Contact vulvitis does not necessarily cause erythema, but it can lead to symptoms of burning, rawness, and irritation.
Allergic vulvitis can be mild, manifesting with erythema, swelling, and itching, or severe with bright red swelling, discomfort, and possibly blistering. Allergic reactions can take longer to develop and range from mild to severe. Identifying and removing the offending irritant while giving supportive care to the affected tissues is the initial step.
If the symptoms fail to respond, biopsy of the affected area could be considered. However, biopsies of tissues demonstrating persistent erythema in a setting of normal vulvar anatomy are not helpful in management or treatment, as the pathology report usually gives a nonspecific diagnosis, such as chronic inflammation.
Organisms that can cause infection the vulva include yeast, herpes simplex virus, HPV, methicillin-resistant Staphylococcus aureus (MRSA), and group B streptococci. These infections tend to be clinically evident, and biopsy is not usually indicated. If the lesions are atypical, biopsy is advisable. If a woman who is compliant with treatment recommendations does not respond to therapy, consider biopsy to ensure that the diagnosis is correct.
Obese women and women with diabetes mellitus are often treated for vaginal/vulvar symptoms without examination, especially if their hemoglobin A1c levels are abnormal. Yeast infection is commonly assumed in these patients, and oral therapy is frequently prescribed. An examination is advised to ensure that no other skin condition or abnormality is causing the symptoms. A biopsy is indicated to confirm any abnormality.
Inflammatory conditions seen on the vulva include lichen simplex chronicus (LSC), lichen sclerosus (LS), lichen planus (LP), Crohn disease and vulvar psoriasis. LSC is a common condition resulting from a chronic itch-scratch cycle or rubbing that leads to the development of epithelial thickening and hyperkeratosis (Figure 1).
The onset of symptoms can relate to an irritant, an allergic response, or chronic yeast infection. Dermal keratin causes an increased texture to the area involved, with accentuations of normal skin markings. Dark-complected skin will take on a gray hue, while light-complected skin will take on a white hue. In some women, distinguishing LSC from LS is difficult without a biopsy (Figure 2).
Autoimmune conditions often manifest in the vulva. Compared with other women, a woman who has a systemic autoimmune illness, such as thyroid disease, diabetes mellitus, systemic lupus erythematosus, fibromyalgia, or irritable bowel disease, will have a higher risk of developing an autoimmune vulvar disease. LS is an autoimmune chronic skin condition that is found more commonly in postmenopausal women and prepubescent girls. It causes structural changes in the anatomy, with resorption of the labia minora, clitoral phimosis, and whitening of the vulvar skin.
It is important to remember that any inflammatory disorder can cause resorption of normal vulvar architecture, so biopsy can be very helpful in making an accurate diagnosis. Vulvar carcinoma occurs in approximately 2% to 5% of women with LS who have extensive involvement and poor control and management. Carcinoma can occur under the thickened white skin of the vulva (Figure 3).
LP is an autoimmune condition that can affect the mucosa of the vulva and the vagina and is found on the gums in the mouth. Mild disease consists of fine, subtle, white, interlacing papules (Wickham striae), whereas more severe disease presents as erosive tissue in the vestibule surrounded by white epithelium. Erythematous plaques can be found deep within the vaginal vault.
Without early identification and treatment, the introitus or vagina can become completely obliterated. Often the intense erythematous tissues are misdiagnosed for candidiasis or a contact or allergic dermatitis. A biopsy will confirm LP. Women with a confirmed diagnosis should be referred to a specialist for long-term management.
Crohn’s disease can occur in the vulva as a direct extension of the involved bowel or as granulomas separated from the bowel by normal tissue. Vulvar inflammation with abscesses, draining sinuses, edema, and ulceration is common. In some patients, the lesions take on the appearance of knifelike fissures. Vaginal granulomas and enteric fistulas from the rectum, ileum, proximal colon to the vagina, perineum and/or vulva can develop.
A biopsy is necessary in these women, especially those without a diagnosis of Crohn’s disease. These women require referral to a gastroenterologist for management, because once the Crohn’s disease is under control, the vulvar symptoms will subside.