Diagnostic studies
Examination of the vaginal discharge
can provide a significant amount of diagnostic in formation. The vaginal pH should always be determined and saline microscopy performed. The addition of 10 percent potassium hydroxide is particularly helpful in diagnosing candida vaginitis.
The distinguishing features of common causes of vaginits is summarized in table 2. Specific syndromes are described in the following secitions
Section II: Specific Vaginitis Syndromes
Bacterial Vaginosis
Bacterial vaginosis is the most common cause of vaginitis in women of childbearing age.
Bacterial vaginosis represents a complex change in vaginal flora characterized by a reduction in the prevalence and concentration of hydrogen peroxide-producing lactobacilli and an increase in the prevalence and concentration of Gardnerella vaginalis; mobiluncus species; Mycoplasma hominis; anaerobic gram-negative rods belonging to the genera prevotella, porphyromonas, and bacteroides; and peptostreptococcus species. The mechanism by which this flora imbalance occurs is unclear. Bacterial vaginosis may be transmitted sexually, although the number of organisms transmitted by this route is not sufficient to cause infection.
Clinical features
Many women with bacterial vaginosis are asymptomatic. Those with symptoms present with an unpleasant, "fishy smelling" discharge that is more noticeable after unprotected intercourse. The discharge is off-white, thin, and homogeneous. Pruritus and inflammation are absent. Dysuria and dyspareunia are also rare.
Upto 20% of pregnant women have bacterial vaginosis. Several studies have reported an increased risk of preterm birth in these women. The risk is directly attributable to bacterial vaginosis and linked to chorioamnionitis. Trials in high-risk women with asymptomatic bacterial vaginosis have demonstrated significant reductions in preterm labor when the infection is treated. Routine screening and treatment for bacterial vaginosis may be required in pregnancy.
The diagnosis of bacterial vaginosis is clinical; criteria have been established that are remarkably simple and useful in clinical practice.
- Typical malodorous, homogeneous, grayish-white discharge
- Vaginal pH greater than 4.5
- Positive whiff-amine test, defined as the presence of a fishy odor when 10 percent KOH is added to vaginal discharge samples
- Clue cells on saline wet mount or gram stain
Three of the four criteria are necessary for diagnosis, although the first three are sometimes present in in patients with trichomoniasis. The presence of clue cells is the single most reliable predictor of bacterial vaginosis. Clue cells are vaginal epithelial cells studded with adherent coccobacilli that are best appreciated at the edge of the cell. These may be mixed in a single specimen with normal epithelial cells. Gram staining of vaginal secretions is more reliable than wet mount for the diagnosis of bacterial vaginosis. Vaginal culture has no role in the diagnosis of bacterial vaginosis. Although cultures for G. vaginalis are positive in almost all cases, the organism may be detected in 50 to 60 percent of healthy asymptomatic women.
The most successful oral therapy for bacterial vaginosis is metronidazole. Typical regimens include 500 mg twice daily or 250 mg three times daily. Single-dose therapy with 2 g of metronidazole achieves a similar immediate rate of clinical response, but higher rates of recurrence have been reported. It is not necessary to treat sexual partners.
Topical vaginal therapy with 2 percent clindamycin cream (5 g once daily for 7 days) or 0.75 percent metronidazole gel (5 g once or twice daily for five days) is as effective as oral metronidazole. A three-day course of topical clindamycin appears to achieve similar early cure rates. The choice of oral versus topical therapy depends upon patient preference.
Triple-sulfa creams, erythromycin, tetracycline, acetic acid gel, and povidone-iodine vaginal douches are significantly less effective therapies.
Asymptomatic infection
Asymptomatic bacterial vaginosis has typically not been treated since patients often have spontaneous improvement over a period of several months. However, evidence linking asymptomatic bacterial vaginosis with obstetrical and gynecologic complications has caused this policy to be reassessed, especially with the availability of topical therapy. It appears reasonable to treat asymptomatic bacterial vaginosis before pregnancy and elective gynecologic surgery.
Relapse
Approximately 30 percent of patients with initial responses to therapy have a recurrence of symptoms within three months. The explanation for this high rate of recurrence is unclear. Reinfection is possible, but recurrence more likely reflects a failure to eradicate the offending organisms or to reestablish the normal protective vaginal flora dominated by lactobacillus.
Management of symptomatic relapse includes prolonged therapy for 10 to 14 days, although maintenance antibiotic regimens have largely been disappointing. No study has demonstrated reduced rates of recurrence in women whose partners were treated with metronidazole. New approaches suggested but not yet available include exogenous lactobacillus recolonization with selected bacteria-containing suppositories.
Candida vulvovaginitis
Candida vulvovaginitis accounts for approximately one-third of vaginitis cases. At least one episode of vulvovaginal candidiasis is reported in up to 75 percent of premenopausal women. The condition is rare before menarch and is less common in postmenopausal women unless they are taking estrogen replacement therapy.
Microbiology and risk factors
Candida albicans is responsible for 80 to 92 percent of episodes of vulvovaginal candidiasis. An increased frequency of other candida species, particularly C. glabrata, has been reported more recently, possibly due to widespread use of over-the-counter drugs, long-term use of suppressive azoles, and the use of short courses of antifungal drugs.
Sporadic attacks of vulvovaginal candidiasis usually occur without an identifiable precipitating factor, except in patients with uncontrolled diabetes mellitus. Some, but not all, women are prone to vulvovaginal candidiasis while taking antibiotics; inhibition of normal bacterial flora by broad-spectrum antibiotics favors yeast growth. Vulvocandidiasis has been reported in a significant number of women treated with oral metronidazole or vaginal antimicrobials for bacterial vaginosis. The risk of vulvovaginal candidiasis may be higher in women who use oral contraceptives containing high levels of estrogen. Vaginal sponges and intrauterine devices have been associated with vulvovaginal candidiasis; spermicides have not. Symptomatic infection may be more common in pregnancy.
While vulvovaginal candidiasis is not traditionally considered a sexually transmitted disease there is an increase in the frequency of vulvovaginal candidiasis at the time most women begin regular sexual activity. Individual episodes of vulvovaginal candidiasis do not appear to be related to lifetime numbers of sexual partners or the frequency of coitus, but may be linked to orogenital sex.
Clinical features
Vulvar pruritus is the dominant feature of vulvovaginal candidiasis. Women may also complain of dysuria (typically perceived to be external or vulvar rather than urethral), soreness, irritation, and dyspareunia. There is often little or no discharge; that which is present is typically white and clumpy.
Physical examination often reveals erythema of the vulva and vaginal mucosa. The discharge is classically described as thick, adherent, and "cottage cheese-like." However, it may also be thin and loose, indistinguishable from the discharge of other types of vaginitis.
Diagnosis
The vaginal pH is typically 4 to 4.5, which distinguishes candidiasis from trichomonas or bacterial vaginosis. The diagnosis is confirmed by finding the organism on a wet mount of the discharge; adding 10 percent potassium hydroxide destroys the cellular elements and may facilitate recognition. Although, empiric therapy is often considered in women with typical clinical features, a normal vaginal pH, and no other organisms visible on microscopy, every effort should be made to confirm the diagnosis and avoid empiric therapy. Culture should be performed in patients with persistent or recurrent symptoms.
Other conditions to be considered in the differential diagnosis include hypersensitivity, allergic or chemical reactions, and contact dermatitis. Failure to recognize the frequency of local adverse reactions results in the empirical prescription of additional topical agents, including high potency steroids, that further aggravate symptoms.
Treatment of Vaginal Candidiasis
Drug Formulation Dosage regimen
Butoconazole 2 percent cream 5 g/day for 3 days
Clotrimazole 1 per cent cream 5 g/day for 7-14 days
100 mg vaginal tablet 1 / day for 7 days or 2/day for 3 days
500 mg vaginal tablet 1 tablet
Miconazole 2 percent cream 5 g/day for 7 days
100 mg vaginal suppository 1/day for 7 days
200 mg vaginal suppository 1/day for 3 days
1200 mg vaginal suppository 1 suppository
Tioconazole 2 percent cream 5 g/day for 3 days
6.5 percent cream 5 g in a single dose
Terconazole 0.4 percent cream 5 g/day for 7 days
0.8 percent cream 5 g/day for 3 days
80 mg vaginal suppository 1/day for 3 days
Nystatin * 100,000 U vaginal tablet 1/day for 14 days
Ketoconazole 400 mg oral tablet Twicea day for 5 day
Itraconazole 200 mg oral tablet Twice a day for 1 day
200 mg oral tablet Once a day for 3 days
Fluconazole 150 mg oral tablet Single dose
There are no significant differences in efficacy among topical and systemic azoles (cure rates >80 percent for uncomplicated vulvovaginal candidiasis)
Therapy
Many therapeutic options are available (see table). Topical antimycotic drugs achieve cure rates in excess of 80 percent. More convenient oral azole agents also are associated with high cure rates; only fluconazole is approved by the United States Food and Drug Administration (FDA). Fluconazole maintains therapeutic concentrations in vaginal secretions for at least 72 hours after the ingestion of a single 150 mg tablet.
The efficacy of oral and vaginal therapy is comparable. The absence of superiority of any formulation, agent, or route of administration suggests that patient preference should influence the selection of a drug for uncomplicated infections characterized by mild to moderate symptoms. Side effects of single-dose fluconazole (150 mg) tend to be mild and infrequent, including gastrointestinal intolerance, headache, and rash. Oral azoles are contraindicated in pregnancy.
Women with severe inflammation or host factors suggestive of complicated infection are less likely to respond to short courses of antimycotic drugs and require 10 to 14 days of therapy. Host factors that predispose to complicated infection include uncontrolled diabetes, immunosuppression, and a history of recurrent vulvovaginal candidiasis. Microbial determinants include candida species other than C. albicans, particularly C. glabrata, which are less susceptible to azoles.
Sexual transmission of candida can occur. However, partner treatment is not necessary since this is not a primary route of transmission. Women with mild infection may respond within a couple of days. More severe infections may take up to 14 days to fully improve. Women may resume intercourse when the discomfort resolves.
Recurrent vulvovaginal candidiasis
Recurrent vulvovaginal candidiasis is defined as four or more episodes of infection per year; it occurs in less than 5 percent of healthy women.
Predisposing factors for recurrent infection are apparent in only a minority of women, and include uncontrolled diabetes and immunosuppressive therapy and abnormalities in locally vaginal mucosal immunity and possibly HIV.
The treatment of women with recurrent infections can be difficult. Attempts should be made to eliminate or reduce risk factors for infection (eg, improve glycemic control, switch to lower dose oral contraceptive). Treatment should also be directed at the sexual dysfunction and marital discord that frequently accompany chronic vaginitis. Antifungal maintenance suppressive therapy taken for six months after an initial induction regimen has resulted in negative cultures in multiple studies of women with recurrent vulvovaginal candidiasis. Regimens include ketoconazole (100 mg per day), itraconazole (50 to 100 mg per day), fluconazole (100 mg per week), and clotrimazole (500 mg vaginal suppositories administered once per week). Treatment failure is not uncommon in patients with C. glabrata vaginitis. Moderate success can be achieved with topical boric acid (600 mg once daily for two weeks) or topical flucytosine in women infected with this organism, although maintenance regimens remain unavailable.
Trichomoniasis
Trichomoniasis affects approximately 180 million women. The disorder is virtually always sexually transmitted. The responsible organism, trichomonas vaginalis, is a flagellated protozoan that is identified in 30 to 40 percent of the male sexual partners of infected women; carriage in men is self-limited and transient. Trichomoniasis is associated with a high prevalence of other sexually transmitted diseases and facilitates transmission of the human immunodeficiency virus (HIV). Spermicidal agents such as nonoxynol 9 reduce the transmission of trichomonas.
Clinical features
Trichomoniasis in women ranges from an asymptomatic carrier state to severe, acute, inflammatory disease. Classic signs and symptoms include a purulent, malodorous, thin discharge with associated burning, pruritus, dysuria, and dyspareunia. Physical examination often reveals erythema of the vulva and vaginal mucosa. Punctate hemorrhages may be visible on the vagina and cervix.
The consequences of trichomoniasis are potentially important in pregnant women in whom untreated infection is associated with premature rupture of the membranes and prematurity. In addition, it is a risk factor for the development of post-hysterectomy cellulitis.
Diagnosis
None of the clinical features of trichomonas vaginitis is sufficiently sensitive or specific to allow a diagnosis based upon signs and symptoms alone. Diagnostic clues include an elevated vaginal pH and increase in polymorphonuclear leukocytes on saline microscopy; these findings are almost invariably present.
The wet mount is positive for motile trichomonads in only 50 to 70 percent of culture-confirmed cases. Trichomonads are often seen on Papanicolaou smears, but this method has a sensitivity of only 60 to 70 percent and false positive results are not uncommon. Asymptomatic women with trichomonas identified on Pap smear should not be treated until the diagnosis is confirmed.
Culture on Diamond's medium has a high sensitivity (95 percent) and should be considered in patients with elevated vaginal pH, increased numbers of polymorphonuclear leukocytes, and an absence of motile trichomonads and clue cells; or when microscopy is unavailable or yields unreliable results.
