Chapel Hill, N.C. — Diagnosis of vulvar ulcers involves evaluation of lesion morphology in correlation with the setting and other clinical findings, and it is relatively easy because ancillary lab testing is usually not necessary and the differential diagnosis comprises a short list, says Libby Edwards, M.D., clinical associate professor of dermatology, University of North Carolina, Chapel Hill, N.C.

The first step in establishing the diagnosis of a vulvar ulcer is to confirm that the lesion is a true ulcer, not a superficial erosion. Then, for practical purposes, the entities to consider include aphthae, herpes simplex virus (HSV) infection in an immunosuppressed patient, hidradenitis suppurativa, Crohn's disease and trauma.

"Chancre is often the first diagnosis that comes to mind when one thinks about genital ulcers. However, for patients seen in the community outside the setting of a public health clinic, ulcers associated with syphilis or other sexually transmitted diseases are pretty uncommon," Dr. Edwards says.

Dr. Edwards notes that aphthae should come to mind if the patient is an adolescent or teen, because these vulvar ulcers generally affect girls ages 11 to 18 years old. While vulvar aphthae can also develop in adult women, they are uncommon.

Patients can present with a single or multiple lesions, and the ulcers can be found on modified mucous membranes or dry keratinized skin, but they rarely appear in the perianal region. Morphologically, the ulcers are generally well demarcated and they can vary in size.

"These ulcers can be large and cause scarring. However, even a small vulvar aphthous ulcer can be very painful and can progress," Dr. Edwards tells Dermatology Times.

Ulcer characteristics, the clinical setting and a history of a sudden onset of pain in the absence of other remarkable findings in an adolescent suggest the diagnosis.

"If you are worried about HSV or syphilis, you can culture and order serology studies, but if it is early after the infection has occurred, the serological results may come back falsely negative. Obtaining a biopsy in this setting is unnecessary and painful," Dr. Edwards says.

Treatment

Treatment of vulvar aphthae requires oral prednisone combined with local measures for pain control, including cool soaks. The usual prednisone dose is 40 mg to 60 mg every morning, continued just until the pain subsides.

Secondary cellulitis is uncommon, but antibiotics may be prescribed if suspected. Secondary yeast infection should be considered in girls who are menstruating and being treated with an antibiotic, or who present for referral after antibiotic therapy.

In contrast to oral aphthae, vulvar aphthae in girls usually occur as a one-time event. Dr. Edwards notes recurrences affect about 20 percent of patients in her practice, but they typically are not frequently recurrent. However, she says one patient developed ulcers every month coincident with menses and accompanied by crippling malaise and fatigue. To avoid frequent use of prednisone bursts, the child is being treated with an anti-TNF-alpha agent and is doing well.

"For most patients who develop recurrences, I tell the parents to call me, but I also give them a prescription for prednisone so that treatment can be started immediately in case the ulcer onset occurs over a weekend," she says.

She also says that the presence of large vulvar aphthae is not diagnostic of Behcet's disease, even when these lesions occur together with oral aphthae and malaise, and that clinicians should be careful not to bring up that systemic multisystem disease.

"Aphthae of the vulva and mouth is complex aphthosis and does not constitute Behcet's disease. Classic Behcet's occurs in Eastern countries, not in the Western world; occurs primarily in men; (and) produces inflammatory eye disease and blindness, central nervous system disease with morbidity, and inflammatory arthritis.

"If you mention the 'B' word, you will cause parents to become unnecessarily frightened, because they are likely to seek out information about this condition online," Dr. Edwards says.