| Feature | Herpes (HSV) | Chancroid (H. ducreyi) | Syphilis (T. pallidum) | Granuloma Inguinale (K. granulomatis) | LGV (C. trachomatis) |
|---|---|---|---|---|---|
| Pain | Painful | Very Painful | Painless | Painless | Ulcer is painless; buboes are painful |
| Ulcer | Multiple vesicles → shallow ulcers | Deep, purulent, ragged edges | Single, hard, clean base | Beefy-red, bleeds easily | Small, transient, shallow |
| LNs | Tender, bilateral | Painful, unilateral, suppurative | Painless, bilateral | None (pseudobuboes, subcutaneous extension of the granulomatous process) | Painful, large, unilateral (buboes) |
| Dx | PCR, Tzanck smear | ”School of fish” (Gram stain) | Darkfield microscopy, Serology | Donovan bodies on biopsy | NAAT, Serology |
Tip
- HSV has systemic symptoms, but this is uncommon in chancroid!
- Lymphogranuloma venereum has painless genital ulcer, but has painful, fluctuant lymph nodes (buboes)
- Add Anogenital warts (Condylomata acuminata), which could be painful or not