# Vaginitis and Cervicitis: Diagnosis and Management

## Overview

Vaginitis is one of the most common reasons for gynecologic office visits, accounting for approximately 10 million visits per year in the United States. The three most common causes are bacterial vaginosis (40 to 50%), vulvovaginal candidiasis (20 to 25%), and trichomoniasis (15 to 20%). Accurate diagnosis requires history, examination, and point-of-care or laboratory testing rather than empiric treatment based on symptoms alone, because symptoms overlap considerably among these conditions. Mixed infections occur in 20 to 30% of cases, further complicating clinical assessment.

## Bacterial Vaginosis (BV)

### Pathophysiology

Bacterial vaginosis is a polymicrobial condition characterized by a shift from the normal Lactobacillus-dominant vaginal flora to an overgrowth of anaerobic organisms. Key organisms include Gardnerella vaginalis, Atopobium vaginae, Prevotella, Mobiluncus, Megasphaera, Sneathia, and BV-associated bacteria (BVAB1-3). BV is not a sexually transmitted infection, though it is associated with sexual activity and new partners. Biofilm formation on the vaginal epithelium is a major contributor to the high recurrence rate.

### Clinical Features

The discharge is thin, homogeneous, and grayish-white with a fishy odor that becomes more pronounced after intercourse or during menses. BV is usually not associated with vulvar irritation or pruritus, which helps distinguish it from candidiasis. The vaginal pH is elevated above 4.5. Notably, up to 50% of women with BV are asymptomatic.

### Diagnosis

The Amsel criteria require 3 of 4 findings: homogeneous, thin, grayish-white discharge; vaginal pH above 4.5; a positive whiff test (fishy amine odor upon addition of 10% KOH); and clue cells on wet mount, defined as 20% or more of epithelial cells stippled with adherent bacteria. The Nugent scoring system uses a Gram stain of the vaginal smear scored from 0 to 10, with scores of 7 to 10 indicating BV; this is the gold standard for research purposes. Molecular testing using platforms such as the BD Max BV panel or Aptima BV assay is increasingly used and can detect Gardnerella, Atopobium, Megasphaera, and Lactobacillus. Point-of-care pH and amine testing is also available.

### Treatment

First-line options include metronidazole 500 mg orally twice daily for 7 days, metronidazole 0.75% vaginal gel applied intravaginally nightly for 5 days, or clindamycin 2% vaginal cream applied intravaginally at bedtime for 7 days. Alternatives include clindamycin 300 mg orally twice daily for 7 days or secnidazole 2 g orally as a single dose. In pregnancy, symptomatic BV is treated with metronidazole 500 mg orally twice daily for 7 days, which is safe in all trimesters, or metronidazole vaginal gel. For recurrent BV, defined as 3 or more episodes in 12 months, the acute episode is treated first, followed by maintenance therapy with metronidazole vaginal gel twice weekly for 4 to 6 months. Boric acid 600 mg vaginal suppositories nightly for 2 to 3 weeks after standard treatment is another option. Partner treatment does not prevent recurrence based on current evidence, including the StepUpRCT, which showed no benefit for male partner treatment.

### Complications

BV increases the risk of acquiring sexually transmitted infections including HIV, HSV, Chlamydia, and gonorrhea. In pregnancy, BV is associated with preterm birth, preterm premature rupture of membranes, and chorioamnionitis, though routine screening of asymptomatic pregnant women is not recommended by ACOG or the USPSTF. BV also increases the risk of post-surgical infection, particularly cuff cellulitis after hysterectomy.

<image>Wet mount microscopy images comparing normal vaginal flora (Lactobacillus-dominant with clean epithelial cells), bacterial vaginosis (clue cells with stippled borders, absent lactobacilli), vulvovaginal candidiasis (budding yeast and pseudohyphae on KOH prep), and trichomoniasis (motile trichomonads with many white blood cells)</image>

## Vulvovaginal Candidiasis (VVC)

### Microbiology

Candida albicans accounts for 85 to 90% of cases. Non-albicans species include C. glabrata (the most common non-albicans species), C. tropicalis, C. krusei, and C. parapsilosis. Non-albicans species are more common in recurrent or refractory VVC, in diabetic patients, and in immunosuppressed patients, and they are often azole-resistant.

### Classification

Uncomplicated VVC is sporadic, mild to moderate, caused by C. albicans, and occurs in an immunocompetent patient. Complicated VVC is defined as recurrent (4 or more episodes per year), severe, caused by non-albicans species, or occurring in immunocompromised patients, during pregnancy, or with uncontrolled diabetes.

### Clinical Features

Vulvar pruritus is the most prominent symptom. Patients may also report burning, soreness, dyspareunia, and external dysuria. The classic discharge is thick, white, and described as "cottage cheese," though this is not always present. The vulva shows erythema, edema, fissures, and excoriations. A critical distinguishing feature is that the vaginal pH is normal, below 4.5, which helps differentiate candidiasis from BV and trichomoniasis.

### Diagnosis

Wet mount with 10% KOH reveals pseudohyphae and budding yeast, though sensitivity is only 50 to 70%. Vaginal pH below 4.5 supports the diagnosis. Vaginal culture should be obtained when non-albicans species are suspected, in recurrent VVC, or when microscopy is negative but clinical suspicion remains high. Molecular testing is available, often as part of vaginitis panels. Empiric treatment without laboratory confirmation should be avoided because overdiagnosis of VVC is very common.

### Treatment

#### Uncomplicated VVC

Over-the-counter topical azoles are effective: miconazole 2% cream for 7 days, miconazole 200 mg suppository for 3 days, miconazole 1,200 mg suppository for 1 day, or clotrimazole 1% cream for 7 to 14 days or 200 mg suppository for 3 days. Oral fluconazole 150 mg as a single dose is the most convenient option with equivalent efficacy.

#### Complicated VVC

For severe episodes, fluconazole 150 mg is given on day 1 and day 3. For recurrent VVC with 4 or more episodes per year, induction therapy consists of fluconazole 150 mg every 72 hours for 3 doses, followed by maintenance with fluconazole 150 mg weekly for 6 months. The recurrence rate after stopping maintenance is approximately 50%. Oteseconazole (Vivjoa) is an FDA-approved novel antifungal for recurrent VVC maintenance. For non-albicans species, especially C. glabrata, which is often fluconazole-resistant, options include boric acid 600 mg vaginal suppository nightly for 14 to 21 days, nystatin 100,000-unit vaginal suppository for 14 days, or flucytosine 5% vaginal cream. Culture with sensitivity testing guides treatment in these cases. During pregnancy, only topical azoles are used, with a 7-day course preferred. Oral fluconazole is avoided in pregnancy due to FDA safety concerns regarding high-dose first-trimester use.

## Trichomoniasis

### Microbiology

Trichomonas vaginalis is a flagellated protozoan that is sexually transmitted. It is the most common non-viral sexually transmitted infection worldwide, with approximately 3.7 million cases per year in the United States. Trichomoniasis often coexists with other STIs and disproportionately affects Black women in the United States, representing a significant health disparity.

### Clinical Features

The classic discharge is copious, frothy, yellow-green, and malodorous, though this is not always present. Patients report vulvovaginal pruritus, burning, dyspareunia, and dysuria. The strawberry cervix (colpitis macularis), characterized by punctate hemorrhagic spots on the cervix, is seen in only 2 to 5% of patients on speculum examination but can be identified in up to 45% on colposcopy. The vaginal pH is elevated above 4.5, usually above 5.0. Up to 50% of infected women are asymptomatic.

### Diagnosis

Wet mount shows motile, flagellated trichomonads with many white blood cells, though sensitivity is only 50 to 60%. Nucleic acid amplification testing (NAAT) is the gold standard with sensitivity above 95% and can be performed on a vaginal swab, urine, or liquid-based cytology specimen. The OSOM Trichomonas Rapid Test is a rapid antigen test with 80 to 90% sensitivity. Culture using the InPouch system has high sensitivity but requires 3 to 7 days and is useful when NAAT is unavailable.

### Treatment

The preferred first-line regimen is metronidazole 500 mg orally twice daily for 7 days, which has a higher cure rate than the single-dose regimen. Tinidazole 2 g orally as a single dose is an alternative that is better tolerated and has a higher cure rate. Single-dose metronidazole at 2 g is acceptable but has lower cure rates, especially in women with HIV. All sexual partners must be treated, and expedited partner therapy (providing a prescription for the partner) should be used when necessary. A test of cure by NAAT is recommended at 3 months because reinfection is common. In pregnancy, metronidazole 500 mg orally twice daily for 7 days is safe in all trimesters, and treatment is given regardless of symptoms due to the association with preterm birth and low birth weight. For metronidazole-resistant trichomoniasis, tinidazole 2 to 3 g daily for 14 days is used, and persistent cases should be referred to the CDC for STD consultation.

## Comparison of Common Vaginitis Causes

| Feature | Bacterial Vaginosis | Vulvovaginal Candidiasis | Trichomoniasis |
|---|---|---|---|
| Discharge | Thin, homogeneous, gray-white | Thick, white, "cottage cheese" | Frothy, yellow-green |
| Odor | Fishy (worse after intercourse) | None | Malodorous |
| Pruritus | Minimal | Prominent | Variable |
| pH | >4.5 | <4.5 (normal) | >4.5 (usually >5.0) |
| Wet mount | Clue cells | Pseudohyphae/budding yeast (KOH) | Motile trichomonads, many WBCs |
| STI | No | No | Yes |
| First-line Tx | Metronidazole 500 mg PO BID x 7 days | Fluconazole 150 mg PO x 1 | Metronidazole 500 mg PO BID x 7 days |
| Partner treatment | Not recommended | Not needed | Required |

## Desquamative Inflammatory Vaginitis (DIV)

Desquamative inflammatory vaginitis is a chronic purulent vaginitis not caused by infection. It may represent a variant of erosive lichen planus or an autoimmune process. The features include copious yellow-green purulent discharge, vulvovaginal burning, dyspareunia, and erythema. Wet mount shows massive white blood cells, parabasal cells, and absent lactobacilli, with no identifiable pathogens. The vaginal pH is above 4.5. Treatment consists of intravaginal clindamycin 2% cream nightly for 2 to 4 weeks, with intravaginal hydrocortisone used if clindamycin fails. Recurrence is common.

## Cervicitis

### Definition

Cervicitis is inflammation of the cervix characterized by mucopurulent endocervical discharge and/or easily induced endocervical bleeding (friability).

### Etiology

Infectious causes include Chlamydia trachomatis, Neisseria gonorrhoeae (the most common infectious agents), Mycoplasma genitalium, HSV, and Trichomonas vaginalis. Non-infectious causes include irritation from douching or foreign bodies, allergic reactions, radiation, and malignancy.

### Clinical Features

Mucopurulent or purulent endocervical discharge is visible at the os or on a swab. Endocervical friability, meaning bleeding on swab insertion, is characteristic. Many patients are asymptomatic. Associated symptoms may include abnormal vaginal bleeding (particularly postcoital), dysuria, and dyspareunia.

### Diagnosis

NAAT for Chlamydia and gonorrhea is performed on a vaginal or cervical swab or urine sample. NAAT for Mycoplasma genitalium should be obtained if available, especially in cases of persistent cervicitis. Wet mount for Trichomonas is performed. Wet mount of endocervical discharge showing 10 or more white blood cells per high-power field suggests cervicitis. Gram stain may reveal intracellular gram-negative diplococci indicating gonorrhea.

### Treatment (CDC STI Treatment Guidelines 2021)

Presumptive treatment is recommended if NAAT results are pending and the patient is at risk for not returning for follow-up. This consists of ceftriaxone 500 mg intramuscularly as a single dose for gonorrhea coverage plus doxycycline 100 mg orally twice daily for 7 days for chlamydia coverage. When chlamydia is confirmed, doxycycline 100 mg orally twice daily for 7 days is the preferred treatment, which is now recommended over azithromycin per the 2021 guidelines. When gonorrhea is confirmed, ceftriaxone 500 mg intramuscularly (or 1 g if body weight is 150 kg or greater) is given plus doxycycline 100 mg orally twice daily for 7 days if chlamydia has not been excluded. For Mycoplasma genitalium, doxycycline 100 mg orally twice daily for 7 days is given first, followed by moxifloxacin 400 mg daily for 7 days, with resistance-guided therapy using macrolide resistance testing preferred. Sexual partners from the past 60 days should be treated. Test of cure consists of NAAT for gonorrhea at 2 weeks and retesting at 3 months for both gonorrhea and chlamydia.

<image>Clinical images of cervicitis findings: normal cervix for comparison, mucopurulent discharge at the cervical os in chlamydial cervicitis, endocervical friability with contact bleeding, and strawberry cervix (colpitis macularis) in trichomoniasis</image>

## Clinical Pearls

Vaginitis should not be treated empirically based on symptoms alone. Accurate diagnosis requires at least pH measurement, wet mount microscopy, or molecular testing, because symptoms of the three major causes overlap considerably.

Clue cells on wet mount are pathognomonic for bacterial vaginosis, budding yeast and pseudohyphae confirm candidiasis, and motile trichomonads confirm trichomoniasis. These findings are definitive when present, though their absence does not exclude the diagnosis.

BV is not an STI, and partner treatment has not been shown to reduce recurrence based on current evidence.

Non-albicans Candida, especially C. glabrata, is often fluconazole-resistant. Culture is essential in recurrent VVC that fails azole therapy to identify the species and guide treatment.

Boric acid 600 mg vaginal suppository is a key treatment for azole-resistant candidiasis and serves as adjunctive therapy in recurrent BV.

Trichomoniasis is a sexually transmitted infection. All sexual partners must be tested and treated, and retesting at 3 months is recommended because reinfection is common.

The 2021 CDC guidelines now recommend doxycycline over azithromycin as first-line treatment for chlamydia due to rising macrolide resistance and evidence of better cure rates.

NAAT is the gold standard for diagnosing trichomoniasis with sensitivity above 95%. Wet mount misses up to 50% of cases.

## References

- CDC Sexually Transmitted Infections Treatment Guidelines (2021)
- ACOG Practice Bulletin No. 215: Vaginitis in Nonpregnant Patients (2020)
- Sobel JD. Vulvovaginal candidosis. Lancet. 2007;369:1961-1971
- Bradshaw CS et al. Current treatment of bacterial vaginosis. Curr Infect Dis Rep. 2016;18:36
- Kissinger P. Trichomonas vaginalis: a review of epidemiologic, clinical and treatment issues. BMC Infect Dis. 2015;15:307
- Workowski KA et al. CDC STI Treatment Guidelines 2021. MMWR Recomm Rep. 2021;70(4):1-187