Single or multiple ulcerative lesions on the genitalia are one of the most common manifes-tations of STDs. Infection may begin as a papule or pustule and evolve into an ulcer. Table 70 – 2 lists the major features of genital ulcerations. The nature of the ulcer and whether it is painful are significant differential features. The ulcer (chancre) of syphilis is typically single, firm and indurated but painless, whereas genital herpes ulcers are often multiple and quite painful. The evaluation of genital ulcers usually focuses on the separation of genital herpes, the most common cause in industrialized nations, and syphilis from other causes. In the laboratory workup, it should be emphasized that direct microscopy and sero-logic tests may be negative at the time of presentation of the syphilitic chancre and that cul-tures for herpes simplex virus are usually positive from vesicular, pustular, or ulcerative lesions but may be negative from crusted areas. Chancroid caused by Haemophilus ducreyi, relatively rare in the developed world, may be suggested by direct microscopy but requires a special selective medium for culture. Granuloma inguinale, a disease also seen primarily in developing countries, is characterized by chronic, persistent genital papules or ulcers.
It is caused by Calymmatobacterium granulomatis, an encapsulated Gram-negative bacillus, which has not been grown in artificial medium. The diagnosis is usually made by examina-tion of Wright- or Giemsa-stained impression smears from biopsy specimens that demon-strate clusters of encapsulated coccobacilli in the cytoplasm of mononuclear cells.
Copyright © 2018-2020 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.