Comprehensive Comparison Table – Vaginal Infections (Clinical Pharmacist Focus)
| Feature | Bacterial Vaginosis (BV) | Vulvovaginal Candidiasis (VVC) | Trichomoniasis | Aerobic Vaginitis (AV) (less common) | Chlamydia / Gonorrhea Vaginitis-like symptoms (STIs mimicking vaginitis) |
|---|---|---|---|---|---|
| Etiology / Pathogens | Gardnerella vaginalis, anaerobes → ↓ Lactobacilli | Candida albicans (90%) non-albicans (C. glabrata, C. krusei) | Trichomonas vaginalis (protozoa, STI) | E. coli, Strep agalactiae, S. aureus | Chlamydia trachomatis, Neisseria gonorrhoeae |
| Risk Factors | New sexual partner, douching, smoking, IUD | Antibiotics, diabetes, pregnancy, immunosuppression, tight clothing | Unprotected sex, multiple partners | Postmenopausal estrogen deficiency, vaginal trauma | High-risk sexual behavior, adolescents |
| Symptoms | Thin gray-white discharge, fishy odor, worse after sex, minimal itching | Thick cottage-cheese discharge, intense itching, soreness, dysuria | Frothy yellow-green discharge, foul odor, vaginal irritation, strawberry cervix | Severe inflammation, purulent discharge, dyspareunia | Purulent mucopurulent discharge, pelvic pain, dysuria |
| Vaginal pH | > 4.5 (↑) | Normal (≤ 4.5) | > 4.5 (↑) | > 4.5 (↑) | Variable |
| Diagnostic Tools | Amsel criteria: clue cells, whiff test; NAAT | KOH microscopy, cultures for recurrent/non-albicans | NAAT = gold standard, wet mount (motile protozoa – low sensitivity) | Vaginal smear score | NAAT (genital swab or urine) |
| 1st-Line Treatment | Metronidazole 500 mg PO BID × 7 d OR Metronidazole gel 0.75% intravaginal x 5 d OR Clindamycin cream | Fluconazole 150 mg PO x1 OR topical azoles × 7 d | Metronidazole 2 g PO single dose OR 500 mg PO BID × 7 d | Treat based on pathogen (e.g., clindamycin, topical steroids in atrophy-related) | Chlamydia: Doxycycline 100 mg BID × 7 d; Gonorrhea: Ceftriaxone 500 mg IM x1 (+ doxycycline if coinfection) |
| Pregnancy Treatment | Metronidazole (safe) topical preferred | Topical azoles × 7 d (fluconazole oral avoid in pregnancy) | Metronidazole 500 mg BID × 7 d (avoid single high dose in pregnancy) | Clindamycin vaginal | Ceftriaxone + azithromycin (doxycycline avoided in pregnancy) |
| Partner Treatment | ❌ NO | ❌ NO | ✅ YES treat partners | ❌ No | 🔸 Only for STI (screen partners) |
| Recurrent Management | Metronidazole gel 0.75% BIW × 4–6 months | Fluconazole suppression 150 mg weekly × 6 months; consider boric acid 600 mg × 14 d for non-albicans | Condom use; consider re-treat if recurrent | NA | Depends on STI protocol |
| Clinical Complications | ↑ HIV risk, ↑ PTL in pregnancy, PID | Recurrent VVC, non-albicans azole resistance | ↑ HIV risk, ↑ infertility, cervicitis, PID | Dyspareunia, chronic vaginitis | Infertility, PID, chronic pelvic pain |
| Monitoring / Counseling | Avoid alcohol with metronidazole (systemic), avoid douching | Advise loose cotton underwear, avoid fragrance products, OTC misuse caution | Abstain from sex until treated & asymptomatic; test for other STIs | Address estrogen deficit if postmenopausal | Screen for co-existing STIs, ensure follow-up |
Clinical Pharmacist Quick Pearls
| Infection | Key Takeaways |
|---|---|
| BV | Most common; treat metronidazole; avoid alcohol with systemic; recurrence common → consider suppressive gel |
| VVC | Fluconazole single dose works; pregnancy requires topical; recurrent → weekly suppression |
| Trichomonas | Sexually transmitted; ALWAYS treat partner; recommend full STI screening |
| AV | Often misdiagnosed; look for purulent discharge + inflammation; treat based on culture |
| STI Presenting Like Vaginitis | Always rule out Chlamydia/Gonorrhea with NAAT in sexually active patients |
Diagnostic Algorithm (Fast Clinical Use)
1️⃣ Discharge + fishy odor → pH > 4.5 → BV
2️⃣ Thick white pruritic discharge + normal pH → Candida
3️⃣ Yellow-green frothy discharge + cervical petechiae → Trichomonas
4️⃣ Severe inflammation + purulent discharge → consider Aerobic Vaginitis
5️⃣ Pain, pelvic tenderness, at-risk sexual exposure → Screen for STI
