Chancroid is caused by Haemophilus ducreyi. Following a 4- to 10-day incubation period, patients develop erythematous papules that evolve into pustules. The pustules then erode forming painful ulcers. Differential diagnosis should include other causes of genital ulcerations including genital herpes and syphilis. Painful, suppurative inguinal lymphadenopathy develops in almost 50% of cases. Large infected lymph nodes may spontaneously rupture. Systemic symptoms are uncommon.
Management and Disposition
Treat with a single dose of ceftriaxone 250 mg IM or oral azithromycin 1000 mg. Ciprofloxacin 500 mg orally twice daily for 3 days is an alternative. Refer for follow-up examination in 7 days to evaluate response to treatment. Aspirate or incise and drain large fluctuant buboes to prevent spontaneous rupture and fistula tract formation. Sexual partners should be empirically treated.
Chancroid is a clinical diagnosis as culture is technically difficult and not widely available.
The ulcerative lesions of chancroid are very tender and usually multiple.
Chancroid is less common than genital herpes and syphilis. Consider concurrent treatment for these infections as definitive testing for chancroid may not be available.
Methicillin resistant Staphylococcus aureus (MRSA) penile shaft infections may mimic STIs.
Chancroid Lesions. Multiple painful, deep ulcerations of chancroid. (Photo contributor: H. Hunter Handsfield, MD. From Handsfield HH, ed. Atlas of Sexually Transmitted Diseases, 3rd ed. New York: McGraw Hill; 2011.)
Chancroid. Painful ulcerations on an erythematous base of the glans and penile shaft in a sexually active male. (Photo contributor: Lawrence B. Stack, MD.)
Methicillin-Resistant Staphylococcus aureus (MRSA) Infection of the Penis. Lesion from MRSA infection of penis mimics LGV, syphilis, herpes, and chancroid. (Photo contributor: Adam Nicholson, MD.)