285 - Chancroid

Abstract

Haemophilus ducreyi is a Gram negative facultative anaerobic bacterium that causes chancroid, a genital ulcer disease endemic in Africa and Asia that facilitates transmission of HIV-1. Although once thought to be exclusively sexually transmitted, H. ducreyi was recently recognized as a major cause of non-sexually transmitted cutaneous ulcers in children in yaws-endemic countries of Africa and the South Pacific islands. In chancroid, infected female sex workers serve as a reservoir for H. ducreyi, and transmission is thought to occur via microabrasions during intercourse. In cutaneous ulcers, asymptomatic colonization of the skin, flies, and fomites provide environmental reservoirs that allow the bacterium to cause infection following minor skin trauma. In genital ulcers, H. ducreyi is frequently co-transmitted with herpes simplex virus and Treponema pallidum, the causative agent of syphilis, while in cutaneous ulcers, co-infection is common with Treponema pallidum subsp. pertenue, the causative agent of yaws. Although genital and cutaneous ulcers caused by H. ducreyi are typically nonindurated and very painful with ragged edges, clinical diagnosis is unreliable, and definitive diagnosis requires either a positive culture or polymerase chain reaction test. The most reliable treatment regimens are macrolides, quinolones, or third generation cephalosporins.