Chancroid

A sexually transmitted disease caused by the gram-negative bacillus Haemophilus ducreyi

Incubation period is 3–5 days

Initial lesion at the site of inoculation is a vesicopustule that breaks down to form a painful, soft ulcer with a necrotic base, surrounding erythema, and undermined edges

Multiple lesions, started by autoinoculation, and inguinal lymphadenitis often develop

Lymphadenitis

• Usually unilateral

• Consists of tender, matted nodes of moderate size with overlying erythema

• Nodes may become fluctuant and rupture spontaneously

With lymph node involvement, fever, chills, and malaise may develop

Balanitis and phimosis are frequent complications in men

Women may have no external signs of infection

Culturing a swab of the lesion onto special medium

A single dose of either azithromycin, 1 g orally, or ceftriaxone, 250 mg intramuscularly, is effective

Effective multiple-dose regimens

• Erythromycin, 500 mg four times daily orally for 7 days

• Ciprofloxacin, 500 mg twice daily orally for 3 days