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Granuloma Inguinale



Sheldon R. Morris

, MD, MPH, University of California San Diego

Last full review/revision Jan 2021| Content last modified Jan 2021
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Granuloma inguinale is a rare sexually transmitted disease caused by the bacteria Klebsiella granulomatis. It leads to chronic inflammation and scarring of the genitals.

  • Granuloma inguinale typically causes a painless, red lump on or near the genitals, which slowly enlarges, then breaks down to form a sore.

  • Doctors suspect the infection if people have typical symptoms and live in areas where the infection occurs, and doctors confirm the diagnosis by examining a sample of fluid scraped from the sore.

  • Treatment with antibiotics is usually effective.

Granuloma inguinale is extremely rare in developed countries but still occurs in Papua New Guinea, Australia, southern Africa, the Caribbean, and parts of Brazil and India.

Symptoms of Granuloma Inguinale

Symptoms of granuloma inguinale usually begin 1 to 12 weeks after infection. The first symptom is a painless, red nodule that slowly enlarges into a round, raised lump. The lump then breaks down to form a foul-smelling sore near the site of the initial infection:

  • Penis, scrotum, groin, and thighs in men

  • Vulva, vagina, and surrounding skin in women

  • Face in both sexes

  • Anus and buttocks in people who have anal intercourse

The sores slowly enlarge and spread to nearby tissue, causing further damage. Sores may also spread when they come into contact with other areas of the body. Without treatment, the sores continue to spread.

Sores heal slowly and may result in permanent scarring.

Occasionally the infection spreads through the bloodstream to the bones, joints, or liver.

Diagnosis of Granuloma Inguinale

  • Examination of fluid from the sore

Granuloma inguinale is suspected in people who live in areas where the infection occurs and who have sores typical of the infection.

To confirm the diagnosis of granuloma inguinale, doctors take a sample of fluid scraped from the sore and examine it under a microscope.

If the diagnosis is unclear, doctors take a sample of tissue and examine it under a microscope (biopsy).

Prevention of Granuloma Inguinale

The following general measures can help prevent granuloma inguinale (and other sexually transmitted diseases):

  • Avoidance of unsafe sex practices, such as frequently changing sex partners or having sexual intercourse with prostitutes or with partners who have other sex partners

  • Prompt diagnosis and treatment of the infection (to prevent spread to other people)

  • Identification of the sexual contacts of infected people, followed by counseling or treatment of these contacts

Not having sex (anal, vaginal, or oral) is the most reliable way to prevent sexually transmitted diseases but is often unrealistic.

Treatment of Granuloma Inguinale

  • An antibiotic, such as trimethoprim-sulfamethoxazole or doxycycline

  • Testing and treatment of sex partners

Trimethoprim-sulfamethoxazole, doxycycline, erythromycin, ciprofloxacin, or azithromycin taken by mouth for at least 3 weeks is effective. Sometimes antibiotics are given by injection into a muscle or vein.

When treated, people usually begin to improve within 7 days. Healing may be slow and sores may recur. Then, treatment is required for a longer time. After treatment appears successful, people should be checked periodically for 6 months.

Current sex partners should be examined and, if infected, treated.

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