Chancroid
Related Subjects:
| Treponema
| Bejel (Endemic Syphilis)
| Pinta
| Yaws (Frambesia)
| Syphilis
| Non-Gonococcal Urethritis
| Gonococcal Urethritis
| Lymphogranuloma Venereum (LGV)
| Chancroid
| Donovanosis
⚠️ The ulcers of Chancroid are typically painful in men but often unnoticed in women.
It remains an important cause of genital ulcer disease in endemic regions and is a recognised cofactor in HIV transmission.
📘 About
- Chancroid is a sexually transmitted infection caused by Haemophilus ducreyi, a Gram-negative coccobacillus.
- It primarily affects the genital mucosa but may also involve oral sites after oral-genital contact.
- Transmission occurs via direct contact with an open lesion; incubation is typically 3–10 days.
- More common in tropical, low-income regions with limited access to STI screening.
🧫 Aetiology & Pathogenesis
- H. ducreyi invades the epithelial barrier and causes necrotising inflammation with polymorphonuclear infiltration.
- This leads to formation of a soft, painful ulcer (“soft chancre”) — in contrast to the painless hard ulcer of primary syphilis.
- Ulcers often coalesce and may be accompanied by suppurative lymphadenitis (bubo formation).
🩺 Clinical Features
- Painful genital ulcers — classically soft, with ragged edges and a grey/yellow purulent base.
- Lesions can occur on the penis, vulva, perianal area, or oral mucosa.
- Unilateral, tender inguinal lymphadenopathy occurs in about half of cases; nodes may suppurate and discharge.
- Women may have internal lesions (e.g., vaginal, cervical) with minimal external findings → diagnosis often delayed.
🔍 Investigations
- Culture: Specific media (e.g. Mueller–Hinton agar with 5% haemoglobin) — rarely available outside reference labs.
- PCR: Highly sensitive and specific for H. ducreyi; confirms diagnosis where available.
- Serological tests: Screen for co-infection with HIV, syphilis, and HSV-2, which often coexist.
🧠 Differential Diagnosis
- Syphilis — single painless ulcer, indurated edge, positive treponemal serology.
- Genital herpes — multiple painful vesicles/ulcers with recurrent pattern.
- LGV (Chlamydia L1-L3) — transient ulcer followed by painful lymphadenopathy and systemic symptoms.
- Donovanosis — beefy-red painless ulcers with rolled margins.
💊 Management
- First-line therapy:
- Azithromycin 1 g orally in a single dose, or
- Ceftriaxone 250 mg intramuscularly in a single dose.
- Alternative therapy:
- Ciprofloxacin 500 mg orally twice daily for 3 days, or
- Erythromycin 500 mg orally four times daily for 7 days.
- In pregnancy and lactation, use Azithromycin or Ceftriaxone (avoid Ciprofloxacin).
- Ulcers usually improve symptomatically within 3 days and heal within 7 days.
- Sexual partners within the past 10 days should be examined and treated.
⚕️ Public Health & Follow-up
- Notifiable condition in many regions.
- All patients should be tested for HIV, syphilis, and gonorrhoea.
- Advise abstinence until ulcers are fully healed.
- Failure to heal within 7–10 days → reassess for co-infection, reinfection, or antibiotic resistance.
📚 References
🕓 Revisions
- 2025-10 — Reviewed and expanded by Dr O’Kane (Makindo edition)
