Ulcus molle, or soft chancre (synonyms: chancroid; Ducrey bacilli; Haemophilus ducreyi; chancre, soft; ulcus molle venereum; ulcus venereum; ulcer molle; soft chancre; ICD-10 A57: Ulcus molle (venereum)) is a disease caused by the bacterium Haemophilus ducreyi (gram-negative rods).
The pathogen produces two potent cytotoxins. These cause both the formation and the slow healing tendency of ulcers (boils). These are local inflammations of the skin and/or mucosa.
The disease belongs to the sexually transmitted diseases (STD) or STI (sexually transmitted infections).
Furthermore, the disease belongs to the “tropical venereal diseases“. These include the bacterial infections lymphogranuloma venereum (LGV), ulcus molle and granuloma inguinale (GI; synonyms: granuloma venereum, donovanosis). The three diseases have in common that they are primarily associated with ulcers (genital ulcer disease, GUD).
Humans currently represent the only relevant pathogen reservoir.
Occurrence: The disease is common in parts of Africa (tropics), Southeast Asia and Latin America. In Germany it is very rare, it is when imported infections.
The contagiousness of the pathogen is high. The pathogen is very sensitive to cold and dehydration.
Transmission of the pathogen (route of infection) occurs through sexual contact (direct mucosal contact with the secretions of open ulcers (ulcers) or affected lymph nodes). In this process, the infection is carried by microtraumas.
The incubation period (time from infection to onset of disease) is usually only 3 to 7 days (1-14 days).
Sex Ratio: It is mainly males who are affected by the infection; the male-to-female ratio is reported to be 3:1 to 25:1.
It is estimated that up to 7 million people worldwide are newly infected each year. Up to 10% of those affected also have other sexually transmitted diseases such as syphilis at the same time.
Course and prognosis: The disease is painful. In women, however, about half of the infections are asymptomatic (without symptoms). With early and consistent therapy, the course and prognosis are favorable. Even if swelling of the regional lymph nodes has already occurred, the prognosis is still good. Sexual partners should also be treated if necessary.
Note: Possible co-infection with HIV.
In Germany, the disease is not notifiable according to the Infection Protection Act (IfSG).
