Introduction
Chancroid is an infectious disease caused by Haemophilus ducreyi, a small gram-negative bacillus.
It is common in the tropics, especially in Africa, the Far East, and the Caribbean.
Persons may present with chancroid outside endemic regions; sporadic outbreaks of infection occur in Europe and North America.
Clinical features
- Incubation period is about 3-7 days
- It begins as a small, tender papule, changing into a pustule which rapidly progresses to a painful ulcer with a bright red areola.
- Neither the edge nor base of the ulcer is indurated (unlike syphilis)
- The ulcer feels soft, hence the name ‘soft sore’ (ulcus molle)
- With superimposed bacterial infection, it often feels indurated
- Sites of predilection in men are the prepuce, frenulum, glans or shaft of the penis
- The ulcers may be multiple due to auto inoculation
- In women the labia, fourchette, vestibule, clitoris, cervix, or perineum are favored sites.
- Lesions may cause dyspareunia, pain on voiding or defaecation and vaginal discharge
- Women may be asymptomatic carriers
- About 7 – 14 days after the appearance of the ulcer, a bubo appears
- A mass of gland smatted together, of tenad herent to the overlying skin
- The glands above the inguinal ligament are usually affected, and often there is a unilateral enlargement.
- Central softening is often found and if untreated the bubo may rupture and discharge through a fistula
- The combination of a painful genital ulcer and suppurative inguinal adenopathy is almost pathognomonic of chancroid
- Patient may present with bubo, the initial ulcer having healed
- Atypical lesions have been reported in HIV infected individuals
- More extensive, or multiple lesions
sometimes accompanied by systemicmanifestations such as fever and chills
Complications
- Progressive ulceration and amputation of the phallus, particularly in HIV patients
Differential diagnoses
Other causes of genital ulcers:
- Syphilis
- Herpes
- Granuloma inguinale
- Lymphogranuloma venereum
- Fixed drug eruption
- Erythema multiforme
- Behcet’s disease
- Trauma
- Tuberculous ulcer
- Cancers
Investigations
- Microscopy, culture and sensitivity of discharge from ulcer
- Serological tests e.g. complement fixation (CF); microimmuno-fluorescence (MIF) test; PCR
Treatment objectives
- Eliminate the organism in the patient and sexual partner(s)
- Prevent re-infection
- Prevent complications
- Counsel and screen for possible co-infection with HIV so that appropriate management can be instituted
Drug therapy
Recommended regimen:
- Ciprofloxacin 500 mg orally every 12 hours for 3 days
Or:
- Erythromycin 500 mg orally every 6 hours for 7 days
Or:
Azithromycin 1 g orally as a single dose
Alternative regimen:
- Ceftriaxone, 250 mg by intramuscular injection, as a single dose
Adjuvant therapy
- Keep ulcerative lesions clean
- Aspirate fluctuant lymph nodes through the surrounding healthy skin, preferably from a
superior approach to prevent persistent dripping and sinus formation - Incision and drainage, or excision of nodes may delay healing and is not recommended
Follow-up
- All patients should be followed up until there is clear evidence of improvement or cure
- In patients infected with HIV, treatment may appear to be less effective, but this may be a
result of co-infection with genital herpes or syphilis - Chancroid and HIV infection are closely associated and therapeutic failure is likely to be seen with increasing frequency
- Patients should therefore be followed up weekly until there is clear evidence of improvement
Notable adverse drug reactions, caution and contraindications
- Ciprofloxacin and ceftriaxone (see
gonorrhoea) - Erythromycin and azithromycin (see
chlamydia)
Prevention
Counselling, Compliance, Condom use and Contact treatment.