Chancroid

Key Features

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

• Incubation period is 3–5 days

Clinical Findings

• 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

Diagnosis

• Culturing a swab of the lesion onto special medium

Treatment

• 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