33-28: Granuloma Inguinale

Granuloma inguinale is a chronic, relapsing granulomatous anogenital infection due to Klebsiella granulomatis (previously known as Calymmatobacterium granulomatis). The pathognomonic cell, found in tissue scrapings or secretions, is large (25–90 mcm), and contains intracytoplasmic cysts filled with bodies (Donovan bodies) that stain deeply with Wright stain.

The incubation period is 8 days to 12 weeks. The onset is insidious. The lesions occur on the skin or mucous membranes of the genitalia or perineal area. They are relatively painless infiltrated nodules that soon slough. A shallow, sharply demarcated ulcer forms, with a beefy-red friable base of granulation tissue. The lesion spreads by contiguity. The advancing border has a characteristic rolled edge of granulation tissue. Large ulcerations may advance onto the lower abdomen and thighs. Scar formation and healing occur along one border while the opposite border advances.

Superinfection with spirochete-fusiform organisms is common. The ulcer then becomes purulent, painful, foul-smelling, and extremely difficult to treat.

Several therapies are available. Because of the indolent nature of the disease, duration of therapy is relatively long. The following recommended regimens should be given for 3 weeks or until all lesions have healed: azithromycin, 1 g orally once weekly (preferred); doxycycline, 100 mg orally twice daily; or azithromycin, 1 g orally once weekly; or ciprofloxacin, 750 mg orally twice daily; trimethoprim-sulfamethoxazole, 1 double-strength tablet orally twice a day; or erythromycin, 500 mg orally four times a day.