What are the key risk factors to consider in a patient's history when evaluating for bacterial vaginosis or candidiasis?

Risk Factors for Bacterial Vaginosis and Candidiasis

When evaluating a patient for bacterial vaginosis (BV) or vulvovaginal candidiasis (VVC), prioritize sexual history, previous vaginal infections, hygiene practices, and medical comorbidities, as these are the most clinically relevant predictors of disease.

Bacterial Vaginosis Risk Factors

Sexual and Behavioral History

• Multiple sexual partners is a primary risk factor, as BV results from replacement of normal Lactobacillus flora with anaerobic bacteria including Gardnerella vaginalis 1
• Vaginal douching significantly increases BV risk and recurrence 2, 3
• Previous sexually transmitted infections (STIs) are present in approximately 35% of BV cases 2
• Women who have sex with women show different BV patterns, with lower odds of persistent infection 3

Pregnancy and Reproductive History

• History of preterm delivery identifies high-risk women (35-57% risk of preterm birth) who may warrant screening 4
• Asymptomatic BV occurs in 9-23% of pregnant women, with higher prevalence among African-American women 4
• Up to 50% of women with BV are asymptomatic, making history of previous BV episodes critical 5, 6

Recurrence Patterns

• Age older than 21 years significantly increases odds of recurrent BV (adjusted OR 1.88) 3
• Previous BV treatment is associated with recurrence patterns, with 55.9% showing persistent infection and 30.5% showing recurrent infection over 12 months 3
• History of bacterial vaginosis itself predicts future VVC episodes 7

Vulvovaginal Candidiasis Risk Factors

Medical Comorbidities

• Diabetes mellitus is a well-established risk factor, though present in only 2.34% of VVC cases 2
• Immunosuppression including HIV infection and corticosteroid use increases VVC risk 4
• Broad-spectrum antibiotic use disrupts normal vaginal flora 4

Age and Reproductive Status

• Sexually active age group (15-44 years) comprises 84.5% of VVC cases 2
• Pregnancy is associated with increased VVC incidence, affecting approximately 1.88% of cases 2
• Age younger than 40 years is positively associated with symptomatic VVC episodes 7

Behavioral and Hygiene Factors

• Wearing pantyliners or pantyhose increases VVC recurrence risk ≥2-fold 7
• Vaginal douching affects 27.7% of VVC patients 2
• Consumption of cranberry juice or acidophilus-containing products paradoxically increases recurrence risk ≥2-fold 7

Sexual History

• Married status is present in 69.48% of VVC cases, with 78.4% of sexual partners being the patient's husband 2
• Pre-marital sexual intercourse is documented in 5.63% of cases 2
• Partner treatment is not routinely necessary for VVC, as it is not sexually transmitted 4

Recurrent Infection Patterns

Recurrent Vulvovaginal Candidiasis (RVVC)

• Recurrent VVC (≥4 episodes annually) affects approximately 44-45% of patients presenting with VVC 2, 4
• Previous VVC episodes predict future recurrence, with 40-45% of women experiencing two or more episodes 1
• Resistant Candida species occur in 10-15% of patients with recurrent yeast vulvovaginitis 4

Mixed Infections

• Concurrent BV and VVC occurs in 34% of women with recurrent BV 8
• Symptomatic yeast vaginitis presents as mixed infection in 29% of patients with recurrent BV history 8
• Previous STIs are present in 34.74% of VVC cases 2

Critical Pitfalls to Avoid

• Do not assume absence of symptoms excludes BV, as up to 50% of cases are asymptomatic 5, 6
• Do not rely on Gardnerella vaginalis culture alone for BV diagnosis, as it colonizes the vagina in asymptomatic women; use Amsel criteria or Gram stain instead 4, 9
• Do not overlook mixed infections in patients with recurrent BV, as concomitant candidiasis occurs in one-third of cases and requires simultaneous treatment 8
• Do not routinely treat sexual partners for VVC, as this does not prevent recurrence 4
• Recognize that 25-40% of genital symptoms may not have an identifiable cause despite thorough evaluation 4