Chancroid is a sexually transmitted infection caused by the bacteria Haemophilus ducreyi, which causes painful genital sores.
Chancroid is a sexually transmitted infection (STI) that is rare in the United States and other high-resource countries, occurring primarily in low-resource countries in occasional, local epidemics. Chancroid is a common cause of genital ulcers in areas of Asia, Africa, and the Caribbean.
People who have chancroid (or other STIs that cause genital sores) are more likely to become infected with and to spread the human immunodeficiency virus (HIV).
(See also Overview of Sexually Transmitted Infections.)
Symptoms of Chancroid
Symptoms begin 3 to 7 days after infection. Small, painful blisters form on the genitals or around the anus and rapidly rupture to form shallow, open sores with ragged edges. These sores may enlarge and join together. Occasionally, these sores become deeper and damage other tissues.
The lymph nodes in the groin may form a bubo (an enlarged and tender group of regional lymph nodes). They sometimes become matted together, in some cases forming a collection of pus (abscess). The skin over the abscess may become red and shiny and may break down and discharge pus from the lymph nodes onto the skin. Sores may also form in other areas of the skin.
Diagnosis of Chancroid
A doctor's evaluation
Culture of a sample of pus or fluid
Doctors suspect chancroid in people with one or more painful genital sores (ulcers) that have no obvious cause, especially if they are or have been in areas of the world where the infection is common.
Usually, doctors take a sample of pus or fluid from a sore and send it to a laboratory to be grown (cultured). However, culturing and identifying these bacteria are difficult, so the diagnosis relies more on symptoms and likelihood of being exposed to the infection.
Specific tests for chancroid are not readily available, but blood tests may be done to exclude other causes, such as syphilis and HIV infection.
People with chancroid are at high risk of syphilis and HIV infection, so if initial test results for these other infections are negative, doctors recommend that people with chancroid come back in 3 months to be tested again.
Treatment of Chancroid
An antibiotic
Several antibiotics, given either by mouth or as an injection, are effective for chancroid. The following may be used:
If buboes are causing discomfort, doctors may make an incision to drain them. This treatment is done only if people are taking antibiotics to control the infection.
If sex partners have had sexual contact with the infected person during the 10 days before the person's symptoms began, they are examined and treated regardless of whether they have symptoms of chancroid.
Prevention of Chancroid
The following general measures can help prevent chancroid (and other sexually transmitted infections):
Safer sex practices, including using a condom every time for oral, anal, or genital sex
Decreased risk of exposure to STIs by reducing the number of sex partners, not having high-risk sex partners (people with many sex partners or who do not practice safer sex), or practicing mutual monogamy or abstinence
Prompt diagnosis and treatment of the infection (to prevent spread to other people)
Identification of the sexual contacts of infected people, followed by counseling or treatment of these contacts
