The causative agent for bacterial vaginosis is:

ESIC Nursing Officer -2019 (Shift -1)

Applied Microbiology & Infection control

Easy

Appeared in: ESIC Nursing Officer -2019 (Shift -1)

Explanation

Gardnerella vaginalis is the primary bacterium associated with bacterial vaginosis (BV), a common clinical syndrome.
BV is characterized by a polymicrobial dysbiosis, where the normal Lactobacillus-dominant vaginal flora is replaced by an overgrowth of anaerobic bacteria, including G. vaginalis.
This shift leads to characteristic symptoms such as a thin, grayish-white discharge and a 'fishy' odor, and is diagnosed by criteria including the presence of clue cells and an elevated vaginal pH.
Treatment for BV specifically targets these anaerobic bacteria, with metronidazole and clindamycin being the first-line antibiotics.

Option A: Candida albicans is a fungus (yeast), not a bacterium, and it causes vulvovaginal candidiasis, commonly known as a yeast infection.
Option B: Chlamydia trachomatis is a bacterium that causes the sexually transmitted infection (STI) chlamydia, which is distinct from bacterial vaginosis.
Option C: Herpes simplex is a virus (HSV) that causes genital herpes, an STI characterized by painful blisters or ulcers. It is not a cause of bacterial vaginosis.

Visual 1: Table - A comparative table showing different vaginal infections (Bacterial Vaginosis, Candidiasis, Trichomoniasis) with their causative agent, typical discharge, pH, and key symptoms. This helps differentiate common vaginal conditions.
Visual 2: Micrograph - A microscopic image of 'clue cells' (vaginal epithelial cells studded with bacteria), which are a key diagnostic feature of bacterial vaginosis, contrasted with a normal vaginal smear.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Causative agent of bacterial vaginosis as background academic context rather than a clinical decision trigger.
Correctly identifying the causative agent is crucial for effective treatment. BV is treated with antibiotics like metronidazole or clindamycin, which are ineffective against fungal (Candida) or viral (Herpes) pathogens.
Nurses play a key role in patient education regarding BV, explaining that it's an imbalance of normal flora, not necessarily an STI, and reinforcing the importance of completing the full course of antibiotics to prevent recurrence and complications.
Untreated BV in pregnant women is associated with an increased risk of preterm labor, premature rupture of membranes, and postpartum endometritis.

How to Approach the Question

Step 1: Identify the core of the question, which is to link a specific condition (bacterial vaginosis) with its causative microorganism.
Step 2: Recall or deduce the type of organism associated with 'bacterial' vaginosis. This immediately points towards a bacterium.
Step 3: Evaluate the options. Candida albicans is a fungus. Herpes simplex is a virus. This eliminates two options.
Step 4: Differentiate between the remaining bacterial options: Chlamydia trachomatis and Gardnerella vaginalis.
Step 5: Recall that Chlamydia trachomatis is the agent for the specific STI 'chlamydia', while Gardnerella vaginalis is classically associated with the vaginal flora imbalance that defines the syndrome of bacterial vaginosis.
Step 6: Select Gardnerella vaginalis as the most specific and primary agent linked to bacterial vaginosis.

Concept Tested & Keywords

Q8YgDiGiHQhuEJamsclrRz