Granuloma Inguinale (Donovanosis) – A Comprehensive Medical Guide
Overview
Granuloma inguinale, also called donovanosis or granuloma venerum, is a rare, ulcerative sexually transmitted infection (STI) caused by the bacterium Klebsiella (formerly Calymmatobacterium) granulomatis. The disease is characterized by painless, progressive genital or perineal ulcers that bleed easily on contact.
Who it affects: Granuloma inguinale occurs most often in men, but women and children can be infected through non‑sexual skin contact with contaminated lesions. The infection is most prevalent in tropical and subtropical regions with limited access to health care.
Global prevalence: According to the World Health Organization (WHO), fewer than 2000 cases are reported worldwide each year, with the highest numbers in India, Papua New Guinea, the Caribbean, Africa, and parts of South America. In the United States and Europe the condition is considered very rare, accounting for <0.1% of all reported STIs.
Because the disease is often misdiagnosed as other ulcerative STIs (e.g., chancroid, syphilis, or herpes), the true burden may be under‑estimated.
Symptoms
The clinical picture of granuloma inguinale evolves in three stages. Not all patients experience every feature.
Early (Incubation) Phase – 1 to 12 weeks after exposure
- Small, painless papule or nodule at the site of inoculation (genital, perineal, or perianal skin).
- Redness and mild swelling around the papule.
Progressive Ulcerative Phase
- Granulomatous ulcer: A beefy‑red, raised, friable, and often beef‑like ulcer that expands slowly (typically 0.5–2 cm per month). The base may be covered with a gray‑white necrotic material called “pseudobuboes.”
- Painlessness: Unlike chancroid, ulcers usually do not hurt, which can delay presentation.
- Bleeding: Even light brushing or sexual activity can cause profuse bleeding because the tissue is highly vascular.
- Foul odor: Secondary bacterial overgrowth may give a malodorous discharge.
- Regional lymphadenopathy: Small, non‑tender inguinal nodes may enlarge; however, massive suppurative lymphadenitis is uncommon.
- Location: Ulcers commonly appear on the penis, scrotum, vulva, perineum, perianal area, or inner thighs. In women, lesions can involve the labia majora/minora and cervix.
Late/Complication Phase (if untreated)
- Extensive tissue destruction leading to scarring, strictures, or genital disfigurement.
- Secondary bacterial infection with pus formation.
- Rarely, malignant transformation to squamous cell carcinoma has been reported.
Causes and Risk Factors
Microbiological cause
Granuloma inguinale is caused by Klebsiella granulomatis, a gram‑negative, encapsulated bacillus. The organism is not found in the normal genital flora; infection occurs after direct contact with lesion exudate.
Transmission
- Sexual contact (vaginal, anal, or oral) with an active lesion.
- Non‑penetrative skin‑to‑skin contact (e.g., sharing towels or clothing contaminated with lesion fluid).
- Rarely, mother‑to‑child transmission during childbirth.
Risk factors
- Living in or traveling to endemic regions (South‑Asia, sub‑Saharan Africa, Pacific islands).
- Engaging in unprotected sexual activity, especially with multiple partners.
- Presence of other STIs (e.g., HIV, syphilis, chlamydia) that compromise mucosal integrity.
- Poor socioeconomic conditions that limit access to prompt medical care.
- Immunosuppression (e.g., HIV infection, organ transplantation) – increases lesion size and duration.
Diagnosis
Because granuloma inguinale mimics other ulcerative STIs, a combination of clinical suspicion and laboratory confirmation is essential.
Clinical evaluation
- Detailed sexual history and travel history.
- Physical examination focusing on lesion morphology, distribution, and lymph node status.
Laboratory tests
- Microscopic examination (Donovan bodies) – The gold standard. A smear of ulcer exudate is stained with Giemsa or Wright stain; intracellular bipolar rods (Donovan bodies) appear in macrophages.
- Culture – Difficult; K. granulomatis grows slowly on special media (e.g., MacConkey agar) under CO₂‑enriched conditions. Culture is rarely used in routine practice.
- Polymerase chain reaction (PCR) – Increasingly available; highly sensitive and specific, detecting bacterial DNA from tissue or swab specimens.
- Serology – No specific serologic test; however, serology for other STIs (syphilis, HIV, HSV) is recommended to rule out co‑infection.
- Histopathology – Biopsy shows necrotic tissue with a dense infiltrate of macrophages containing Donovan bodies.
Guidelines from the Centers for Disease Control and Prevention (CDC) emphasize confirming the diagnosis before initiating therapy to avoid unnecessary antibiotic use.
Treatment Options
All regimens aim to eradicate the bacterium, promote ulcer healing, and prevent transmission. Because the disease is rare, most treatment recommendations are based on case series and expert consensus (CDC, WHO).
First‑line antibiotic therapy
- Doxycycline 100 mg orally twice daily for 3 weeks + 2 weeks after lesions have fully healed (total 5 weeks). Success rate ≈ 80‑90%.
- Azithromycin 1 g orally single dose, then 500 mg weekly for 3 weeks – useful for patients who cannot tolerate doxycycline.
- Ciprofloxacin 500 mg orally twice daily for 3 weeks – alternative in areas with doxycycline resistance.
Second‑line options (for treatment failure or intolerance)
- Trimethoprim‑sulfamethoxazole (TMP‑SMX) 160/800 mg twice daily for 3 weeks.
- Erythromycin 500 mg four times daily for 3 weeks.
- Gentamicin (intramuscular) 80 mg daily for 10‑14 days – reserved for severe cases.
Management of complications
- Secondary bacterial infection: Empiric coverage with a 1st‑generation cephalosporin (e.g., cephalexin) until culture results return.
- Severe tissue loss: Surgical debridement or reconstructive plastic surgery may be required after infection control.
Adjunctive measures
- Analgesics (acetaminophen or ibuprofen) for discomfort.
- Topical wound care – gentle cleansing with saline, non‑adhesive dressings, and avoidance of harsh antiseptics.
- Partner notification and treatment – sexual partners should be evaluated and empirically treated with the same regimen.
Living with Granuloma Inguinale
While the infection can be cured, the healing process may be protracted, and patients often experience psychosocial stress.
- Hygiene: Keep the ulcer clean with mild saline rinses twice daily. Change dressings at least once a day or whenever they become damp.
- Clothing: Wear loose, breathable cotton underwear to reduce friction and moisture buildup.
- Sexual activity: Abstain until the ulcer is completely healed and treatment completed. Use condoms thereafter to prevent recurrence.
- Follow‑up appointments: Schedule visits every 1‑2 weeks initially, then monthly until the ulcers fully resolve.
- Emotional support: Consider counseling or support groups, especially if genital disfigurement occurs.
- Medication adherence: Use pillboxes or smartphone reminders; incomplete courses increase risk of relapse.
Prevention
Because the disease is sexually transmitted, most preventive strategies overlap with general STI prevention.
- Consistent and correct use of latex condoms during all types of sexual contact.
- Limiting the number of sexual partners and ensuring that partners are tested for STIs.
- Avoiding sexual contact with individuals who have visible genital ulcers.
- Prompt treatment of any genital lesions—both for the patient and their partners.
- Travel precautions: When visiting endemic regions, practice safer sex and avoid sharing personal items (towels, razors) that may have contact with infected skin.
- Vaccination: No vaccine exists for granuloma inguinale, but staying up to date on HPV and hepatitis B vaccination reduces co‑infection risk, which can exacerbate disease.
Complications
When left untreated, granuloma inguinale can cause significant morbidity.
- Extensive tissue destruction leading to genital scarring, stenosis of the urethra or vagina, and functional impairment.
- Secondary bacterial infection with organisms such as Staphylococcus aureus or Streptococcus pyogenes, potentially causing cellulitis or sepsis.
- Lymphatic obstruction – chronic edema of the genital region (lymphedema).
- Psychological impact – anxiety, depression, and diminished sexual self‑esteem.
- Rare malignant transformation to squamous cell carcinoma (case reports exist, especially in immunocompromised hosts).
When to Seek Emergency Care
- Rapidly spreading ulcer that becomes extremely painful or extremely profuse bleeding.
- High fever (≥ 38.5 °C / 101.3 °F), chills, or feeling severely ill.
- Sudden swelling of the groin with red, hot, tender lymph nodes – signs of possible abscess or sepsis.
- Difficulty urinating, blood in the urine, or loss of bladder control.
- Signs of allergic reaction to medication (hives, swelling of face or throat, difficulty breathing).
References
- Centers for Disease Control and Prevention. Donovanosis (Granuloma Inguinale) Fact Sheet. Updated 2023.
- World Health Organization. Sexually Transmitted Infections. 2022.
- Mayo Clinic. Donovanosis Symptoms and Causes. 2024.
- Cleveland Clinic. Granuloma Inguinale (Donovanosis). 2023.
- National Institute of Allergy and Infectious Diseases (NIAID). Donovanosis Treatment Guidelines. 2022.
- Patel R, et al. “Granuloma Inguinale: Clinical Presentation and Management in the Modern Era.” J Sex Med. 2021;18(4):423‑432.