STD

Donovanosis

  • Cause:
    • Donovanosis is a rare genital ulcer disease caused by the bacterium Klebsiella granulomatis.
    • It is a sexually transmissible infection (STI) but can also be transmitted through skin-to-skin contact and to a baby during birth.
  • Epidemiology:
    • Extremely rare in Australia, with no notifications in Queensland for the 5 years up to 2022.
    • Previously more common in remote areas of Australia.
    • Widespread in some tropical and sub-tropical regions, particularly in Papua New Guinea, Southern Africa, India, and parts of South America.
  • Transmission:
    • Primary Transmission: Presumed to be by direct contact with lesions during sexual activity. Can also be passed through casual skin-to-skin contact and from mother to baby during birth.
  • Timeline
    • Incubation Period: Unknown, but likely between 7 and 112 days.
    • Period of Communicability: Unknown, but likely for the duration of the open lesions on the skin or mucous membranes.

Clinical Presentation

  • Relatively Painless Anogenital Ulceration
  • Lesions may be:
    • Ulcerative: Shallow ulcers that bleed on contact.
    • Proliferative: Raised lesions with a beefy red appearance.
    • Ulcero-proliferative: Combination of ulcerative and proliferative features.
  • Common Sites of Lesions:
    • Genitals, perineum, and perianal area.
  • Secondary Infection:
    • Secondary anaerobic bacterial infection can cause an offensive odor.

Complications

  • Extra-genital Disease:
    • Rare but can occur via auto-inoculation, contiguous spread (e.g., uterus, fallopian tubes), or haematogenous spread (e.g., long bones, psoas muscle).
  • Chronic Ulcers:
    • May lead to lymphatic destruction and subsequent pseudo-elephantiasis of the genitalia.
  • Neoplastic Transformation:
    • Potential for malignant change.
  • Increased HIV Transmission Risk.
  • Vertical Transmission:
    • Possible during vaginal delivery.

Diagnosis of Donovanosis

Site/Specimen and Testing

  • Dry Swab or Punch Biopsy of Lesions:
    • Test: NAAT (Nucleic Acid Amplification Test)
    • Consideration: Highly sensitive and specific but only available in Pathwest laboratories in WA and the Molecular Diagnostics Unit at Royal Brisbane and Women’s Hospital. Discuss with the laboratory before sending the specimen.
  • Punch Biopsy of Lesion:
    • Test: Histology
    • Consideration: Low-to-moderate sensitivity but highly specific. Requires experienced histopathologist as classic Donovan bodies may be sparse. Biopsy if there is any concern about malignant change.

Specimen Collection Guidance

  • Clinician Collected or Self-Collection:
    • Ensure proper technique and handling for accurate results.

Investigations

  • Consider extra-genital disease in patients with current genital infection and in those with a past history of donovanosis presenting with unusual symptoms.

Management of Donovanosis

Principal Treatment Options

  • Anogenital Lesions:
    • Azithromycin 500 mg PO, daily for 7 days
    • OR
    • Azithromycin 1 g PO, once weekly for at least 4 weeks, until complete resolution of lesions
    • Alternative:
      • Doxycycline 100 mg PO, BD for a minimum of 4 weeks, until complete resolution of lesions

Treatment Advice

  • Azithromycin is highly effective and well-tolerated.
  • Seek specialist advice before treating this rare condition.
  • Adherence to treatment is essential to ensure a cure; consider directly-observed therapy.

Other Immediate Management

  • Advise no sexual contact for 7 days after treatment is commenced, or until the course is completed and symptoms resolved, whichever is later.
  • Advise no sex with partners from the last 6 months until the partners have been reviewed and treated if necessary.
  • Contact tracing.
  • Provide patient with a factsheet.
  • Notify the state or territory health department.

Special Treatment Situations

  • Neonates:
    • Born to mothers with untreated donovanosis at the time of delivery should be closely monitored for the development of lesions.
  • Poor Adherence or Disseminated Disease:
    • Patients may require hospital admission.
  • Extended Treatment:
    • Many guidelines recommend treating with azithromycin until lesions have completely healed, but there is no evidence that longer treatment is beneficial. Non-azithromycin regimens should be continued until complete resolution of lesions.

Contact Tracing

  • Contact tracing of sexual partners in the last 6 months is recommended but has a low yield.

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