Granuloma Inguinale

Intracellular Pathogenesis and How Donovan Bodies Form

Replication Inside Macrophages

• Klebsiella granulomatis is an encapsulated Gram-negative bacillus that lives obligately inside large macrophages (histiocytes).
• After entering through tiny breaks in the skin or mucosa, the bacteria are engulfed by macrophages but survive, because their capsule prevents the phagosome from fusing with the lysosome. They then multiply heavily within cytoplasmic vacuoles, forming clusters with a "safety-pin" appearance caused by bipolar staining. These clusters are known as Donovan bodies.

Granulation Tissue Overgrowth and the Pseudobubo

• The bacteria release vascular growth factors (VEGF) and cytokines that drive rampant growth of superficial capillaries and granulomatous connective tissue. This is why the ulcer looks like raw red meat and oozes blood so easily during examination.
• Because K. granulomatis has little tendency to invade the lymphatics (unlike Chlamydia in LGV), it does not cause true lymphadenitis. The red swelling in the groin (pseudobubo) is actually made up of subcutaneous granulomas that spread from the genitals into the adjacent tissue, then soften and break down to form a groin ulcer.

Clinical Forms

Ulcerogranulomatous Form (Most Common):

• The ulcer begins as a small, painless red papule or blister that breaks down into an exuberant ulcer.
• Features: A beefy-red base covered with fine, velvety granulation tissue, with rolled, well-defined edges. The ulcer is painless and not tender, but bleeds with even light contact.

Hypertrophic / Verrucous Form: Lesions rise above the skin as firm, warty plaques with a dry or crusted surface, and are easily confused with squamous cell carcinoma (SCC) or genital warts (condyloma acuminata).

Necrotic Form: Develops when anaerobic bacteria cause a secondary infection. The ulcer is deep, with a dirty gray-black slough and a foul-smelling discharge, and it becomes painful as necrosis destroys large areas of tissue.

Sclerotic / Cicatricial Form: The late stage of the disease, in which persistent bands of contracting scar tissue form in the anogenital region, narrowing the urethral opening and the anus and blocking superficial lymphatics, which leads to genital elephantiasis.

Differential Diagnosis of Granuloma Inguinale (Donovanosis)

Our Diagnostic Process at Haute-Derma

Giemsa / Wright-Stained Tissue Smear (Confirmatory Test):

• The physician takes a small piece of granulation tissue from the raised edge of the ulcer (after cleaning off the surface slough), crushes it between two glass slides or smears it directly onto a slide, and stains it with Giemsa or Wright stain.
• Result: Large macrophages packed with Donovan bodies, which are dark, bipolar-staining, safety-pin-shaped coccobacilli inside cytoplasmic vacuoles.

Dermoscopy and Histopathology Biopsy:

• Dermoscopy shows dense, proliferating loop vessels on an intensely red, congested background.
• A biopsy is mandatory for hypertrophic lesions to rule out squamous cell carcinoma (SCC). It shows a dense infiltrate of plasma cells, neutrophils and macrophages containing Donovan bodies (on silver or Giemsa staining).

Screening for Other STIs: Blood tests include RPR/TPHA (syphilis) and an HIV Ag/Ab combo test, plus PCR for co-infection with HSV, chlamydia and gonorrhea.

Treatment and Recovery at Haute-Derma

Standard Antibiotic Regimens (CDC / WHO Guidelines)

• First-line regimen: Azithromycin 1 g orally once a week OR 500 mg orally once a day for at least 3 weeks (and until the ulcers have completely healed).
• Alternative regimen 1: Doxycycline 100 mg orally twice a day for at least 3 weeks.
• Alternative regimen 2: Erythromycin base 500 mg orally four times a day for 3 weeks.
• Important: If the lesions show no improvement after 7 days of antibiotics, your Haute-Derma physician may consider adding gentamicin 1 mg/kg IV every 8 hours.

Partner Management and Follow-Up

• Treating partners: Anyone who had sexual contact with the patient in the 60 days before symptoms began should be examined and given preventive treatment with a single 1 g dose of azithromycin.
• Monitoring for relapse: Patients should return for monthly check-ups for 6 months after stopping treatment, because K. granulomatis can persist in the tissue and cause a late relapse.

Cosmetic and Structural Restoration at Haute-Derma

• Once the infection is fully cleared and the ulcers have completely closed:
  • Superpulsed fractional CO2 laser: Releases contracting scar bands around the urethra and groin creases and stimulates new collagen.
  • Microneedling radiofrequency (RF): Restores elasticity to genital tissue and reduces mild lymphedema.
  • LED light therapy (633 nm): Speeds wound healing, soothes the skin and reduces post-inflammatory hyperpigmentation.