Treatment of Vaginal Swab Positive for WBCs
The presence of white blood cells on vaginal wet mount indicates inflammation and requires identifying the underlying cause before treatment—you cannot treat WBCs alone, but must diagnose and treat the specific infection causing them. 1
Diagnostic Approach to WBCs on Vaginal Wet Mount
The finding of increased WBCs on saline microscopy is a nonspecific indicator of vaginal inflammation that requires further evaluation to determine the causative organism 1. The key is to examine the wet mount for additional diagnostic features:
Look for These Specific Findings on Wet Mount:
Clue cells (bacterial-covered epithelial cells with stippled appearance and obscured borders) indicate bacterial vaginosis—this is the single most reliable diagnostic finding with 98.2% sensitivity and 94.3% specificity 2, 3
Moving flagellated trichomonads indicate trichomoniasis, though wet mount misses this 30-50% of the time 1
Hyphae or budding yeast indicate vulvovaginal candidiasis 1
Proportion of toxic leucocytes and immature epithelial cells may indicate aerobic vaginitis, a distinct entity from BV 4
Additional Diagnostic Tests to Perform:
Vaginal pH testing: Normal pH should be <4.5; elevated pH (>4.5) suggests bacterial vaginosis or trichomoniasis 1, 2
Whiff test: Mix vaginal secretions with 10% KOH—a fishy odor indicates bacterial vaginosis 2, 5
Cervical examination: Look for friability, hyperemia (suggests STI), strawberry cervix (trichomoniasis), or mucopurulent discharge (cervicitis from gonorrhea/chlamydia) 1
Treatment Based on Diagnosis
If Bacterial Vaginosis is Diagnosed (Clue Cells + 2 of 3 Other Amsel Criteria):
Metronidazole 500 mg orally twice daily for 7 days is the first-line treatment with 95% cure rates 2, 5, 6, 7
Alternative: Metronidazole 2g single dose (lower cure rate of 84%) or clindamycin 2% vaginal cream for 7 days 5, 6
Critical patient instruction: Avoid all alcohol during treatment and for 24 hours after completion to prevent disulfiram-like reactions 5, 6
No routine follow-up needed if symptoms resolve 5
Partner treatment generally not recommended unless recurrent BV 5, 6
If Trichomoniasis is Suspected (WBCs + Mobile Trichomonads):
Metronidazole 2g orally as a single dose achieves 90-95% cure rates 1, 7
Treat sexual partners simultaneously to prevent reinfection 1, 7
If wet mount is negative but clinical suspicion high, obtain NAAT testing (wet mount sensitivity only 40-80%) 2
Same alcohol avoidance instructions apply 1
If Vulvovaginal Candidiasis is Diagnosed (WBCs + Yeast/Hyphae):
Short-course topical azole therapy (3-7 days) achieves 80-90% cure rates for uncomplicated cases 1, 8
Oral fluconazole is an alternative 8
Partner treatment not routinely needed unless recurrent infection 1
Pregnant women require 7-day topical azole therapy only 1
If Aerobic Vaginitis is Suspected (WBCs + Toxic Leucocytes + Immature Cells, No Clue Cells):
Do not treat with metronidazole—this is a critical pitfall 2, 4
Treat with ampicillin or amoxicillin-clavulanate for confirmed aerobic vaginitis 2
Consider local estrogen therapy, corticosteroids, or probiotics depending on microscopic findings 4
If Cervicitis/PID is Suspected (WBCs + Cervical Motion Tenderness + Mucopurulent Discharge):
Empiric broad-spectrum antibiotics covering N. gonorrhoeae, C. trachomatis, and anaerobes must be initiated immediately 1
This requires different treatment than simple vaginitis and has serious long-term sequelae if untreated (infertility, ectopic pregnancy, chronic pain) 9
Parenteral therapy may be needed if no improvement within 72 hours 1
Critical Pitfalls to Avoid
Never diagnose BV without clue cells unless confirmed by Gram stain—treating the wrong condition leads to treatment failure 2
Do not treat asymptomatic patients with incidental bacterial findings and no clue cells 2
Do not rely solely on wet mount for trichomoniasis—obtain NAAT if clinical suspicion exists despite negative wet mount 2
Recognize that WBCs alone are nonspecific—they appear in trichomoniasis, aerobic vaginitis, cervicitis, and PID, each requiring different treatment 1, 4, 9
Avoid treating based on vaginal pH or discharge appearance alone—these are supportive findings but not diagnostic 3