Haemophilus ducreyi is the causative agent of chancroid, one of the genital ulcerative diseases. H. ducreyi is the major cause of genital ulcer disease in Africa and Southeast Asia and is of increasing concern in the United States. Definitive diagnosis of chancroid requires the isolation and identification of H. ducreyi, but isolation of this organism is difficult and the available medium is not optimal for all strains. Fluorescent antibody and serologic tests are of limited value. In general, our knowledge of this organism is rather limited, and indeed, recent studies have questioned the placement of H. ducreyi in the genus Haemophilus. H. ducreyi has relatively few biochemical activities, and epidemiologic studies are limited because there are limited phenotypic markers available for strain typing. Specific virulence factors of H. ducreyi have yet to be identified. Antimicrobial resistance in H. ducreyi is of special concern, as this organism has acquired both gram-negative and gram-positive resistance determinants. In addition, some of these determinants can be mobilized and transferred to other Haemophilus species or to Neisseria gonorrhoeae.

Chancroid and Haemophilus ducreyi.

The significance and scope of reproductive tract infections among Third World women.

Of 97 patients with genital ulcers attending a special treatment clinic in Nairobi, Kenya, 60 harboured Haemophilus ducreyi, four herpes simplex virus, and five Neisseria gonorrhoeae. Eleven patients had serological evidence of syphilis; of these one case was confirmed by darkfield microscopy. In the remaining cases no aetiological agent was identified. An enriched chocolate agar with vancomycin and serum was a useful medium for primary isolation of H ducreyi. Tetracycline was generally ineffective in the treatment of ulcers, but sulfadimidine was successful in almost 80% of cases.

https://sti.bmj.com/content/sextrans/57/6/378.full.pdf

Genital ulcers in Kenya. Clinical and laboratory study.

Epidemiology of chancroid and haemophilus ducreyi in nairobi, kenya

http://repository.usfca.edu/cgi/viewcontent.cgi?article=1033&context=chem_fac

Partial characterization of the major lipooligosaccharide from a strain of Haemophilus ducreyi, the causative agent of chancroid, a genital ulcer disease.

1,000 consecutive cases of venereal disease have been analysed, and the social factors facilitating the spread of this group of diseases are examined and discussed. It is suggested that the latter assume a very significant role, and that any effective eradication programme must take social factors into consideration.

J.W. Kibukamusoke

Papers

Venereal disease in East Africa