Bacterial Vaginosis vs Candida Vulvovaginitis vs Trichomoniasis
Bacterial vaginosis is a common cause of vaginitis and results from disruption of the normal vaginal microbiota. There is an increased risk of acquiring sexually transmitted infections such as HIV and obstetric and gynecologic complications. Bacterial vaginosis ranges from approximately 25 to 30 percent in females of reproductive age. Bacterial vaginosis is due to a complex change in the vaginal microbiota that is characterized by a reduction in dominant lactobacilli which produce hydrogen peroxide and lactic acid and an increase in anaerobic Gram-negative rod bacteria. The normal lactobacilli bacteria produce hydrogen peroxide which is important in preventing the overgrowth of anaerobe. With the loss of lactobacilli, pH rises and massive overgrowth of the vaginal anaerobe occurs.
Clinical Symptoms
Common symptoms that individuals have are vaginal discharge and vaginal odor. The discharge is off-white, thin, homogenous, and has a fishy odor that is more noticeable after sex or during menses. There can be mixed vaginitis symptoms such as dysuria, dyspareunia, pruritus, and vulvovaginal burning or inflammation. Although these are the most common symptoms, up to 70% of individuals present asymptomatic and should still be tested. Pelvic inflammatory disease is much more common in patients with bacterial vaginosis.
Diagnosis
All patients should undergo a physical exam to assess the vaginal discharge and any vulvar excoriations or edema. Several clinical laboratory tests can be performed as well. Nucleic acid amplification tests multiply nucleic acid sequences through polymerase chain reactions to identify evidence of various vaginal pathogens. Other tests include pH testing, microscopy, and amine (whiff) tests. Normal pH in premenopausal women is 4.0-4.5 and in bacterial vaginosis is over 4.5 Vaginal cells are typically squamous epithelial cells, while in bacterial vaginosis they are clue cells, which are squamous epithelial cells studded with coccobacilli. This needs to be differentiated from Candida vulvovaginitis and Trichomoniasis. Candida vulvovaginitis produces odorless, thick, white discharge with budding yeast and pseudohyphae. With this pathogen, the amine test will be negative and pH will be over 4.5. Trichomoniasis is malodorous with purulent discharge and a burning sensation, bleeding, dyspareunia, and dysuria. There are also trichomonas on microscopy and pH over 4.5. However, the amine test in Trichomoniasis is often positive. It is vital to figure out the correct etiology of the disease because treatment and complications vary based on which pathogen it is.
Treatment and Prevention
Patients who are symptomatic and nonpregnant can take Metronidazole 500 mg twice daily orally for seven days or Clindamycin 2% vaginal cream. Symptomatic pregnant patients should only be given oral metronidazole or clindamycin rather than the intravaginal formulation. Asymptomatic patients should undergo observation as it may resolve spontaneously. The only exception to this is patients undergoing gynecologic surgery as they should be treated regardless of symptoms. Sexual activity is a major risk factor for BV and condom use is encouraged to decrease risks. Diets high in fiber have also been associated with a higher likelihood of a Lactobacillus-dominant vaginal microbiome. It is not associated with diabetes or immunocompromised states.
References
Sobel, J. D. (n.d.). UpToDate. UpToDate.
https://www.uptodate.com/contents/bacterial-vaginosis-clinical-manifestations-and-diagnosis?search=bacterial%20vaginosis§ionRank=2&usage_type=default&anchor=H25&source=machineLearning&selectedTitle=3%7E95&display_rank=2#H25 Assessed and Endorsed by the MedReport Medical Review Board