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CHANCROID AND OTHER INFECTIONS

CHANCROID AND OTHER INFECTIONS

Infection by Haemophilus ducreyi results in chancroid, one of a group of infrequently encountered sexually transmitted infections. Chancroid is more common than syphilis in some areas of Africa and Southeast Asia but uncommon in the United States. After incubation of 3 to 10 days, a papule or pustule, surrounded by a vivid areola of inflammation, may be noted within the vestibule, at the fourchette or on the labia minora. This develops into one or more typical “soft chancres.” The chancroid appears as a pinkish-red, granular ulcer with punched-out, uneven, undermined edges and a necrotic, purulent floor. The ulceration is painful and destructive and lacks the characteristic induration seen in the primary chancre of syphilis. Suppurative inguinal nodes or “buboes” are common. The combination of a painful ulcer and tender inguinal adenopathy suggests chancroid; when accompanied by suppurative inguinal adenopathy, they are almost pathognomonic. A definitive diagnosis of chancroid requires identification of H. ducreyi on special culture media that are not widely available; even using these media, sensitivity is 80% or less. Gram stain of material from open ulcers can also be confirmatory.

CHANCROID AND OTHER INFECTIONS
Plate 6-14


Lymphogranuloma venereum is caused by one of a number of serotypes (L-1, L-2, L-3) of Chlamydia trachomatis. Although uncommon in the United States, this infection causes significant morbidity. The initial lesion appears a few days after exposure as a papule, pustule, or erosion on the vulva or within the vagina. It is of short duration, inconspicuous, and, therefore, almost always overlooked. Within 1 to 3 weeks, the tendency toward lymphatic spread becomes evident in the slow development of inguinal adenitis progressing until a painful, matted mass of glands is present, with periadenitis and occasional suppuration and draining sinuses. The extent and severity of inguinal lymphadenitis in the female are less than in the male. When the pelvic and perirectal lymphatics become involved, rectal stricture may result from progressive inflammation and ulceration about the entire circumference of the rectum, with subsequent fibrosis and cicatrization. At times, hypertrophic changes with extensive infiltration and ulceration may involve the vulva, vagina, urethra, and perineum. The destructive process may give rise to fistulae, and blockage of lymph channels may cause elephantiasis. The lymph node pathology is that of a granuloma with multiple abscesses and masses of epithelioid and giant cells. Diagnosis is by complement fixation testing 80% of patients have a titer of 1 : 16 or greater. Genital and lymph node specimens (i.e., lesion swab or bubo aspirate) may be tested for C. trachomatis by culture, direct immunofluorescence, or nucleic acid detection.

Granuloma inguinale (also called donovanosis) is relatively common in the tropics, New Guinea, and Caribbean areas, but accounts for less than 100 cases per year in the United States. This infection is caused by the intracellular gram-negative bacterium Klebsiella granulomatis (formerly known as Calymmatobacterium granulomatis). The incubation period varies. The primary lesion may be seen as a vivid, circumscribed, granulomatous nodule on the vulva, vaginal mucosa, cervix, or in such extragenital sites as the face or neck. The initial lesion spreads by peripheral extension rather than through the lymphatics. The skin and mucous membranes are primarily involved. The disease does not penetrate deeply but may gradually extend to the groin, inner thigh, perianal region, and buttock. The characteristic picture is that of a red, exuberant, granulomatous surface, with well-defined serpiginous margins. The “pseudobubo” sometimes seen is usually a subcutaneous granuloma. Healing occurs slowly, the lesion persisting for many months or years. The diagnosis is established by the appearance of the typical lesions and by demonstration of Donovan bodies in surface smears or biopsies. Chancroid, syphilis, tuberculosis, and carcinoma must be excluded in the differential diagnosis.