From the Guidelines
Vaginitis is an inflammation of the vagina characterized by discharge, odor, irritation, and itching, resulting from disruption of the normal vaginal microbiome, primarily involving infectious causes, hormonal changes, and allergic or irritant reactions. The pathophysiology of vaginitis involves several key mechanisms, including:
- Infectious causes: Bacterial vaginosis occurs when the normal Lactobacillus-dominant flora is replaced by an overgrowth of anaerobic bacteria like Gardnerella vaginalis, leading to an elevated vaginal pH above 4.5 and production of amines causing the characteristic fishy odor, as noted in studies such as 1.
- Hormonal changes: Decreased estrogen during menopause or breastfeeding can lead to atrophic vaginitis by thinning the vaginal epithelium and reducing glycogen production, which diminishes Lactobacilli and increases pH.
- Allergic or irritant reactions: Contact dermatitis can occur when irritants or allergens like soaps, spermicides, or latex trigger inflammatory responses in the vaginal mucosa. The three most common diseases associated with vaginitis are:
- Trichomoniasis, caused by the protozoan Trichomonas vaginalis, which adheres to vaginal epithelial cells and causes microabrasions and inflammation, as described in 1.
- Bacterial vaginosis, caused by a replacement of the normal vaginal flora by an overgrowth of anaerobic microorganisms and Gardnerella vaginalis, as noted in 1.
- Candidiasis, usually caused by Candida albicans, which invades the superficial vaginal epithelium and triggers an inflammatory response, as mentioned in 1. Treatment depends on the specific cause, with options including metronidazole or clindamycin for bacterial vaginosis, antifungals like fluconazole or miconazole for candidiasis, metronidazole or tinidazole for trichomoniasis, and vaginal estrogen for atrophic vaginitis, as recommended in studies such as 1.
From the FDA Drug Label
It is normal for a certain amount of yeast to be found in the vagina. Sometimes too much yeast starts to grow in the vagina and this can cause a yeast infection. Vaginal yeast infections are common About three out of every four adult women will have at least one vaginal yeast infection during their life. Some medicines and medical conditions can increase your chance of getting a yeast infection. If you are pregnant, have diabetes, use birth control pills, or take antibiotics you may get yeast infections more often than other women Personal hygiene and certain types of clothing may increase your chances of getting a yeast infection.
The pathophysiology of vaginitis, specifically yeast infections, involves an overgrowth of yeast in the vagina, which can be triggered by various factors such as:
- Hormonal changes: pregnancy, use of birth control pills
- Medical conditions: diabetes
- Medications: antibiotics
- Personal hygiene and certain types of clothing This overgrowth of yeast can cause symptoms such as itching, burning, redness, soreness, and a thick white vaginal discharge 2.
From the Research
Pathophysiology of Vaginitis
The pathophysiology of vaginitis involves disruptions to the normal vaginal flora, which can be caused by various factors such as infectious agents, hormonal changes, and other conditions.
- Infectious forms of vaginitis, including bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis, occur when the balance of the vaginal flora is disrupted, allowing pathogenic organisms to overgrow and cause infection 3, 4, 5.
- Bacterial vaginosis is characterized by a shift in the normal vaginal flora from aerobic, predominantly lactobacilli, to a predominantly anaerobic flora, with an overgrowth of Gardnerella vaginalis and other anaerobic bacteria 4, 6.
- Vulvovaginal candidiasis is caused by an overgrowth of Candida species, such as Candida albicans, and can be difficult to diagnose due to non-specific symptoms 3.
- Trichomoniasis is caused by the protozoan Trichomonas vaginalis and can cause a foul-smelling, frothy discharge and vaginal inflammatory changes 3, 7.
- Atrophic vaginitis is caused by estrogen deficiency, leading to a thinning of the vaginal epithelium and a decrease in lactobacilli, making the vagina more susceptible to infection 3.
Key Factors Contributing to Vaginitis
- Disruption of the normal vaginal flora, allowing pathogenic organisms to overgrow and cause infection 5.
- Hormonal changes, such as estrogen deficiency, which can lead to atrophic vaginitis 3.
- Introduction of pathogenic organisms into the vagina, such as Trichomonas vaginalis 5.
- Alterations in substrate, allowing an imbalance of microorganisms to develop 5.
- Sexual transmission, which may play a role in the spread of some types of vaginitis, although this has not been proven for all types 4.