What is the characteristic finding on a wet‑mount microscopy for vulvovaginal candidiasis?

Characteristic Wet Mount Finding for Vulvovaginal Candidiasis

The characteristic finding on wet mount microscopy for vulvovaginal candidiasis is the presence of yeast buds, pseudohyphae, or hyphae, typically visualized using 10% potassium hydroxide (KOH) preparation. 1

Diagnostic Microscopy Technique

Specimen Preparation and Examination

• Vaginal secretions should be examined using both saline wet mount and 10% KOH preparation on separate slides 1
• The KOH preparation is superior for identifying yeast and pseudohyphae because it dissolves cellular debris and epithelial cells, making fungal elements more visible 1, 2
• The saline wet mount can also reveal yeast forms but is less sensitive than KOH preparation 1

Specific Microscopic Findings in Candidiasis

• Budding yeast cells (blastospores) and pseudohyphae are the diagnostic features 1, 3
• These fungal elements appear as oval budding cells with branching filamentous structures 4, 3
• The vaginal pH remains normal (4.0-4.5) in candidiasis, which helps distinguish it from other causes of vaginitis 1

Distinguishing Features from Other Vaginal Infections

What You Will NOT See in Candidiasis

• Motile trichomonads: These flagellated protozoa are characteristic of trichomoniasis, not candidiasis 1
• Clue cells: These are epithelial cells covered with bacteria, pathognomonic for bacterial vaginosis, not candidiasis 1
• Elevated pH (>4.5): This finding suggests bacterial vaginosis or trichomoniasis rather than candidiasis 1
• Increased white blood cells alone: While some WBCs may be present, a marked increase in inflammatory cells without yeast suggests other infections like trichomoniasis or cervicitis 1

Critical Diagnostic Pitfalls

Common Errors to Avoid

• Do not diagnose candidiasis based solely on increased white blood cells - this is a nonspecific finding that indicates inflammation but not the specific etiology 1
• The wet mount has approximately 50-70% sensitivity for detecting Candida, so negative microscopy in a symptomatic patient warrants culture 1, 2
• Asymptomatic colonization occurs in 10-20% of women - finding yeast without symptoms does not require treatment 2, 5

When Microscopy is Negative

• If clinical suspicion remains high despite negative wet mount, vaginal culture for Candida should be obtained 1
• Culture is more sensitive than microscopy but takes 24-48 hours for results 1, 3

Clinical Context

Supporting Clinical Features

• Thick, white, "cottage cheese-like" or curdlike vaginal discharge accompanies the microscopic findings 1, 5
• Vulvar erythema, edema, excoriation, and fissures are common physical examination findings 1, 6
• Intense vulvar pruritus and burning are the predominant symptoms 1, 5