A sexually transmitted, progressive infection of the genital skin caused by intracellular bacterium, Calymmatobacterium granulomatis.
Granuloma inguinale is very rare in temperate climates but is more common in some tropical and subtropical areas. Its cause is a gram-negative intracellular bacillus found in mononuclear cells, C. granulomatis (formerly Donovania granulomatis), which does not grow on ordinary culture medium.
Symptoms and Signs
The incubation period varies from about 1 to 12 wk. The initial lesion is a painless, beefy-red nodule that slowly enlarges as an elevated, velvety, malodorous, granulating ulcerated plaque. Sites of infection are the penis, scrotum, groin, and thighs in men; the vulva, vagina, and perineum in women; the anus and buttocks in homosexual men; and the face in both sexes. Lymphadenopathy is absent, and the disease spreads by contiguity and autoinoculation. Lesions progress slowly but eventually may cover the genitalia. Healing is slow with scarring. Secondary infection is common and can cause gross tissue destruction. Hematogenous dissemination to bones, joints, or liver occurs occasionally, and anemia, cachexia, and death may follow in neglected cases.
Bright, beefy-red, moist, smooth, raised lesions are characteristic. Diagnosis is confirmed microscopically by presence of Donovan bodies (intracytoplasmic bacilli in macrophages stained by Giemsa or Wright's stain) in smears taken from scrapings of the edge of lesions. Biopsy specimens from such scrapings contain many plasma cells but few mononuclear cells.
Tetracyclines, macrolides, and trimethoprim-sulfamethoxazole have been used most successfully, but aminoglycosides, quinolones, and chloramphenicol have also been effective. Recommended regimens include azithromycin either 500 mg po daily for 7 days or 1 g po weekly for 4 wk, doxycycline 100 mg po bid for 21 days, erythromycin 800 to 1000 mg po bid for 21 days, or ceftriaxone 1 g IM or IV daily for 14 days. Treatment should elicit a response in 7 days, but healing of extensive disease may be slow and lesions may recur, requiring more prolonged therapy. The patient's sexual contacts should be examined for lesions. Surveillance after apparently successful treatment should continue for 6 mo. HIV-infected patients may require more prolonged treatment.