Vulvovaginitis: Find the cause to treat it
ABSTRACT
Vulvar and vaginal disorders are among the most common problems seen in ambulatory care. The cause is usually infectious, but noninfectious causes should also be considered, and differentiating them can be challenging. Accurate diagnosis based on patient history, physical examination, and laboratory testing is necessary so that effective therapy can be chosen.
KEY POINTS
- Typical presenting symptoms of vulvovaginitis are itching, burning, and abnormal discharge.
- Evaluating vaginal secretions with simple office-based tools is often sufficient for diagnosis, although DNA testing is also available.
- Depending on the cause, vulvovaginitis is generally treated with a course of oral or topical antibiotics, antiviral or antifungal drugs, anti-inflammatory agents, or hormonal therapy.
- Cases that do not resolve may require maintenance therapy. Patients who have persistent or unusual symptoms should be referred to a specialist.
BACTERIAL VAGINOSIS
Bacterial vaginosis is the most common vaginal disorder worldwide. It has been linked to preterm delivery, intra-amniotic infection, endometritis, postabortion infection, and vaginal cuff cellulitis after hysterectomy.3 It may also be a risk factor for human immunodeficiency virus (HIV) infection.4
The condition reflects a microbial imbalance in the vaginal ecosystem, characterized by depletion of the dominant hydrogen peroxide-producing lactobacilli and overgrowth of anaerobic and facultative aerobic organisms such as Gardnerella vaginalis, Mycoplasma hominis, Atopobium vaginae, and Prevotella and Mobiluncus species.
Diagnosis of bacterial vaginosis
The Amsel criteria consist of the following:
- pH greater than 4.5
- Positive whiff test
- Homogeneous discharge
- Clue cells.
Three of the four criteria must be present for a diagnosis of bacterial vaginosis. This method is inexpensive and provides immediate results in the clinic.
The Nugent score, based on seeing certain bacteria from a vaginal swab on Gram stain microscopy, is the diagnostic standard for research.5
DNA tests. Affirm VPIII (BD Diagnostics, Sparks, MD) is a nonamplified nucleic acid probe hybridization test that detects Trichomonas vaginalis, Candida albicans, and G vaginalis. Although it is more expensive than testing for the Amsel criteria, it is commonly used in private offices because it is simple to use, gives rapid results, and does not require a microscope.6 Insurance pays for it when the test is indicated, but we know of a patient who received a bill for approximately $500 when the insurance company thought the test was not indicated.
In a study of 109 patients with symptoms of vulvovaginitis, the Affirm VPIII was found comparable to saline microscopy when tested on residual vaginal samples. Compared with Gram stain using Nugent scoring, the test has a sensitivity of 87.7% to 95.2% and a specificity of 81% to 99.1% for bacterial vaginosis.7
In 323 symptomatic women, a polymerase chain reaction (PCR) assay for bacterial vaginosis was 96.9% sensitive and 92.6% specific for bacterial vaginosis, and Affirm VPIII was 90.1% sensitive and 67.6% specific, compared with a reference standard incorporating Nugent Gram-stain scores and Amsel criteria.8 The test is commercially available.
Management of bacterial vaginosis
Initial treatment. Bacterial vaginosis can be treated with oral or topical metronidazole, oral tinidazole, or oral or topical clindamycin.9 All options offer equivalent efficacy as initial treatments, so the choice may be based on cost and preferred route of administration.
Treatment for recurrent disease. Women who have 3 or more episodes in 12 months should receive initial treatment each time as described above and should then be offered additional suppressive therapy with 0.75% metronidazole intravaginal gel 2 times a week for 4 months. A side effect of therapy is vulvovaginal candidiasis, which should be treated as needed.
In a multicenter study, Sobel et al10 randomized patients who had recurrent bacterial vaginosis to twice-weekly metronidazole gel or placebo for 16 weeks after their initial treatment. During the 28 weeks of follow-up, recurrences occurred in 51% of treated women vs 75% of those on placebo.
Another option for chronic therapy is oral metronidazole and boric acid vaginal suppositories.
Reichman et al11 treated women with oral metronidazole or tinidazole 500 mg twice a day for 7 days, followed by vaginal boric acid 600 mg daily for 21 days. This was followed by twice-weekly vaginal metronidazole gel for 16 weeks. At follow-up, the cure rate was 92% at 7 weeks, dropping to 88% at 12 weeks and 50% at 36 weeks.
Patients with recurrent bacterial vaginosis despite therapy should be referred to a vulvovaginal or infectious disease specialist.
VULVOVAGINAL CANDIDIASIS
Vulvovaginal candidiasis is the second most common cause of vaginitis.
Diagnosis can be clinical
Vulvovaginal candidiasis can be clinically diagnosed on the basis of cottage cheese-like clumpy discharge; external dysuria (a burning sensation when urine comes in contact with the vulva); and vulvar itching, pain, swelling, and redness. Edema, fissures, and excoriations may be seen on examination of the vulva. (Figure 3).
Saline microscopy (Figure 2) with the addition of 10% KOH may reveal the characteristic fungal elements, but its sensitivity is only 50%.
Fungal culture remains the gold standard for diagnosis and is needed to determine the sensitivity of specific strains of Candida to therapy.12
DNA tests can also be helpful. In a study of patients with symptomatic vaginitis, Affirm VPIII detected Candida in 11% of samples, whereas microscopy detected it in only 7%.13 Another study7 found that Affirm VPIII produced comparable results whether the sample was collected from residual vaginal discharge found on the speculum or was collected in the traditional way (by swabbing).
Cartwright et al8 compared the performance of a multiplexed, real-time PCR assay and Affirm VPIII in 102 patients. PCR was much more sensitive (97.7% vs 58.1%) but less specific (93.2% vs 100%), with culture serving as the gold standard.
Management of candidiasis
Uncomplicated cases can be managed with prescription or over-the-counter topical or oral antifungal medications for 1 to 7 days, depending on the medication.9 However, most of the common antifungals may not be effective against non-albicans Candida.
In immunosuppressed patients and diabetic patients, if symptoms do not improve with regular treatment, a vaginal sample should be cultured for C albicans. If the culture is positive, the patient should be treated with fluconazole 150 mg orally every 3 days for 3 doses.14
Patients with recurrent episodes (3 or more in 12 months) should follow initial treatment with maintenance therapy of weekly fluconazole 150 mg orally for 6 months.15
Non-albicans Candida may be azole-resistant, and fungal culture and sensitivity should be obtained. Sobel et al13 documented successful treatment of non-albicans Candida using boric acid and flucytosine. Phillips16 documented successful use of compounded amphotericin B in a 50-mg vaginal suppository for 14 days. Therefore, in patients who have Candida species other than C albicans, treatment should be one of the following:
- Vaginal boric acid 600 mg daily for 14 to 21 days
- Flucytosine in 15.5% vaginal cream, intravaginally administered as 5 g for 14 days
- Amphotericin B 50 mg vaginal suppositories for 14 days.
Boric acid is readily available, but flucytosine vaginal cream and amphotericin B vaginal suppositories must usually be compounded by a pharmacist.
Of note: All that itches is not yeast. Patients with persistent itching despite treatment should be referred to a specialist to search for another cause.
