Last reviewed 07/2021
Chancroid is a tropical sexually transmitted disease caused by Haemophillus ducreyi, a gram negative bacterium.
It is endemic in Africa, Asia and South America, and is more common in men, particularly uncircumcised men. HIV is a very important cofactor, with a 60% association in Africa.
After a one week incubation period a papule develops which becomes a pustule and then an ulcer, which is characteristically very painful, more so in men. The lesion is rarely extragenital. Diagnosis is by Gram-stain of exudate, cultured on enriched media - serology is unreliable.
50% of cases have a painful adenopathy with development of bubos - inflamed lymph nodes with pus and necrosis, fixed to the skin. There is no systemic component.