What else to check in a patient with recurrent vulvovaginal candidiasis (VVC)?

Evaluation of Recurrent Vulvovaginal Candidiasis

Obtain vaginal cultures to confirm the diagnosis and identify the specific Candida species before initiating treatment, as 10-20% of recurrent cases are caused by non-albicans species (particularly C. glabrata) that require different therapeutic approaches. 1, 2

Essential Diagnostic Testing

• Vaginal culture is mandatory to identify the specific Candida species and detect non-albicans organisms like C. glabrata, which respond poorly to standard fluconazole therapy due to intrinsic azole resistance 1, 3, 2
• Consider PCR testing if available, as it demonstrates superior sensitivity (90.9%) and specificity (94.1%) compared to microscopy alone (sensitivity 57.5%, specificity 89.4%) 4
• Do not rely on clinical diagnosis or microscopy alone in recurrent cases, as this leads to misdiagnosis and inappropriate treatment in over 50% of patients 4, 5

Underlying Conditions to Evaluate

Metabolic and Immunologic Factors

• Screen for diabetes mellitus (including hemoglobin A1c), as uncontrolled diabetes significantly impairs treatment response and requires 7-14 days of therapy rather than short courses 4
• Assess HIV status in appropriate clinical contexts, as HIV-infected women have higher colonization rates that correlate with immunosuppression severity 4
• Evaluate for immunosuppression including corticosteroid use or other debilitating medical conditions that reduce response to short-term therapies 4

Medication and Behavioral History

• Review antibiotic use, as widespread antibiotic abuse is a major contributing factor to recurrent vulvovaginal candidiasis 6
• Document oral contraceptive use and exogenous hormone therapy, which are established predisposing factors 6
• Assess for pregnancy, as vulvovaginal candidiasis commonly occurs during pregnancy and requires topical-only therapy for 7 days 4

Critical Diagnostic Pitfalls to Avoid

• Never assume the current infection is the same species as previous episodes without confirmatory testing, as this leads to treatment failure with non-albicans species 1, 3, 7
• Do not initiate empiric fluconazole without culture results, as C. glabrata (present in 10-20% of recurrent cases) requires boric acid 600 mg intravaginally for 14 days as first-line therapy 1, 3, 2
• Recognize that standard laboratory susceptibility testing at pH 7 underestimates resistance, as all antifungals have significantly higher MICs at vaginal pH 4 (terconazole against C. glabrata shows 388-fold higher MIC at pH 4) 4, 3

When to Suspect Alternative Diagnoses

• Reconsider the diagnosis if treatment fails, as unusual vulvar conditions, atrophic vaginitis, inflammatory vaginitis, or allergic reactions may mimic vulvovaginal candidiasis 8, 7
• Evaluate for bacterial vaginosis or trichomoniasis with appropriate testing (Amsel criteria, nucleic acid amplification testing), as these account for 40-50% and 15-20% of vaginitis cases respectively 8
• Consider non-infectious causes (atrophic, irritant, allergic, inflammatory vaginitis) in 5-10% of cases, particularly if cultures are repeatedly negative 8

Host Factor Assessment

The majority of women with recurrent vulvovaginal candidiasis lack identifiable predisposing factors, suggesting genetic predisposition or underdosing as potential mechanisms 4, 6. However, systematic evaluation for the modifiable conditions listed above remains essential before attributing recurrence to idiopathic causes 4.