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Granuloma Inguinale



Sheldon R. Morris

, MD, MPH, University of California San Diego

Last full review/revision Dec 2020| Content last modified Dec 2020
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Granuloma inguinale is a rare, progressive infection of genital and perineal skin caused by Klebsiella (formerly Calymmatobacterium) granulomatis. The disease is characterized by slowly progressive skin lesions that are beefy red, raised, painless, and often ulcerated; regional lymphadenopathy is uncommon. Diagnosis is by clinical criteria and microscopy. Treatment is with antibiotics, usually tetracyclines, macrolides, or trimethoprim/sulfamethoxazole.

Infections with K. granulomatis are extremely rare but have been previously reported in areas such as Papua New Guinea, Australia, southern Africa, the Caribbean, and parts of Brazil and India.

Symptoms and Signs of Granuloma Inguinale

Sites of infection are

  • Penis, scrotum, groin, and thighs in men

  • Vulva, vagina, and perineum in women

  • Anus and buttocks in patients who engage in anal-receptive intercourse

  • Face in both sexes

After an incubation period of about 1 to 12 weeks, a painless, red skin nodule slowly enlarges, becoming a raised, beefy red, moist, smooth, foul-smelling lesion. The lesion slowly enlarges, often ulcerates, and may spread to other skin areas. Lesions heal slowly, with scarring. Secondary infections with other bacteria are common and can cause extensive tissue destruction. Lymphadenopathy is uncommon.

Occasionally, granuloma inguinale spreads through the bloodstream to the bones, joints, or liver; without treatment, anemia, wasting, and, uncommonly, death may occur.

Images of Granuloma Inguinale

Diagnosis of Granuloma Inguinale

  • Microscopic examination showing Donovan bodies in fluid from a lesion

Granuloma inguinale is suspected in patients from endemic areas with characteristic lesions.

Diagnosis of granuloma inguinale is confirmed microscopically by the presence of Donovan bodies (numerous bacilli in the cytoplasm of macrophages shown by Giemsa or Wright stain) in smears of fluid from scrapings from the edge of lesions. These smears contain many plasma cells.

Biopsy specimens are taken if the diagnosis is unclear or if adequate tissue fluid cannot be obtained because lesions are dry, sclerotic, or necrotic. The bacteria do not grow on ordinary culture media.

Treatment of Granuloma Inguinale

  • Antibiotics (various)

Many oral antibiotics kill the bacteria, but tetracyclines, macrolides, and trimethoprim/sulfamethoxazole (TMP/SMX) are most effective, followed by ceftriaxone, aminoglycosides, fluoroquinolones, and chloramphenicol.

Recommended oral regimens include

  • Doxycycline 100 mg twice a day for 3 weeks

  • TMP/SMX 160/800 mg twice a day for 3 weeks

  • Erythromycin 500 mg four times a day for 3 weeks

  • Azithromycin 1 g a week for 3 weeks

IV or IM antibiotics (eg, ceftriaxone) are an alternative.

Response to treatment should begin within 7 days, but healing of extensive disease may be slow and lesions may recur, requiring longer treatment. HIV-infected patients may also require prolonged or intensive treatment. After apparently successful treatment, follow-up should continue for 6 months.

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

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