Which disease of the vagina is caused by overgrowth of bacteria?

• A. Vaginal Candidiasis
• B. Pelvic Inflammatory Disease
• C. Bacterial Vaginosis
• D. Trichomoniasis

Answer: (C)

An imbalance of the vaginal bacterial population is what this question is getting at. Bacterial Vaginosis occurs when the normally dominant lactobacilli are reduced and anaerobic bacteria become more prevalent. That shift in flora is what drives the condition, not an overgrowth of a fungus or a parasite.

This overgrowth of bacteria leads to a thin, gray discharge and a fishy odor, and is typically associated with a vaginal pH higher than 4.5. Diagnostic clues include clue cells on microscopy and a positive fishy-odor test (whiff test).

In contrast, vaginal candidiasis stems from fungal overgrowth, presenting with itching and thick, curd-like discharge rather than a fishy odor. Pelvic inflammatory disease is an infection of the upper genital tract, often involving different organisms and presenting with pelvic pain and systemic symptoms. Trichomoniasis is caused by a protozoan parasite and usually presents with a frothy, sometimes yellow-green discharge and cervicitis.