2.5.9 Granuloma Inguinale

 1A91

Donovaniosis.

Very rare in Europe. Most cases are travel-related; quite frequent and endemic in the tropical and subtropical regions of Africa, India and the Caribbean.

Sexually transmitted infection caused by Klebsiella granulomatis with characteristic ulcerated nodules in the genital and perianal area.

The causative bacterium Klebsiella granulomatis is a gram-negative rod shaped bacterium. Transmission usually occurs via direct, skin or mucosal contact with an infected individual.

The symptoms appear weeks after transmission and there is great individual variation of the incubation time, which may be from 1 week up to 3 months (most frequently 4-6 weeks). Characteristic lesions: ulcerated nodules or plaques appearing on genital and perianal skin and mucous membranes. Some patients develop hypertrophic nodules (verrucous, resembling warts) or necrotic ulcers. Lesions are typically painless and symptoms are mild. Local lymph nodes (mostly inguinal) may be enlarged and drain abscesses into the overlying skin.

See symptoms.

Not applicable.

Usually not necessary. If an ulcer is biopsied, histopathology may show that the macrophages are large and vacuolated, and they contain intracellular bacilli, i.e. Donovan bodies (hence the name Donovanosis). These are best visualized using special stains. Additionally, there is a dermal infiltrate of histiocytes and plasma cells and small neutrophilic abscesses. Klebsiella granulomatis does not stain well in standard microscopy.

Tests such as bacterial culture, nucleic acid amplification tests or serology are usually available only in specialized laboratories.

Primary infection usually lasts 2-3 weeks, but recurrences are shorter, usually 7-10 days; prolonged course is possible in immunocompromised patients (HIV).

Permanent scarring of the genitals and secondary genital lymphedema.

Based on typical clinical features and the detection of microscopically visible Donovan bodies. Screening tests for other STI should be carried out.

Genital herpes simplex and syphilis (primary chancre) and in travel-related cases chancroid. If inguinal lymphadenopathy is present, also lymphogranuloma venereum. In chronic genital ulcers one must also rule out penile or vulvar cancer (squamous cell carcinoma).

Transmission can be prevented by barrier contraception.

Antibiotic treatment is recommended for at least 3-4 weeks or longer until visible lesions have completely healed. Oral azithromycin 1 g (once a week) is considered the first line treatment. Alternatives are p.o. Doxycycline 100 b.i.d. and p.o. Erythromycin 500 mg q.i.d.

Sexual activity should not take place until all lesions have healed. Sexual partners should be requested for clinical examination and treatment. A follow-up examination may be necessary to ensure complete recovery.

Not applicable.