Chancroid

Chancroid is a sexually-transmitted disease rare in the United States, but common in tropical and subtropical areas of Africa, Asia, and Latin America. Unlike the syphilitic chancre, it is painful, shallow, and likely to produce tender inguinal buboes in men.

CASES/YEAR
80 (US); 5,000,000 (Global)
AGENT TYPE
Bacteria
OTHER NAMES
Soft chancre; Haemophilus ducreyi infection;
ACUITY
Acute-Moderate
INCUBATION
3-5 days; up to 2 weeks reported; [CCDM]
INITIAL SYMPTOMS
A tender papule forms pustule, then painful ulcer with erythematous base & ragged borders. Typically, there are 1-3 ulcers, each 1-2 cm in diameter. About 50% of men have tender inguinal buboes (less common in females) 1-2 wks after ulceration.[5MCC-2020]
PRECAUTIONS
"The disease is communicable until the lesions are healed and the organism is cleared from discharging regional lymph nodes. Nonsexual transmission may occur from contact with open lesions." [CCDM, p. 97]
COMMENTS
FINDINGS:
One or more painful ulcers are located in the genital area. Rarely, infections of women are asymptomatic. The skin lesions are often accompanied by painful, swollen lymph nodes that may suppurate and develop into abscesses (buboes). [CCDM, p. 97-8] The tender genital ulcers are usually multiple pustules that may coalesce. The ulcers are deep, purulent, and bleed easily. The edges of the ulcers are "undermined, ragged, irregular." [Harrisons, p. 422] Chancroid ulcers are less indurated ("soft chancres") than the chancres of primary syphilis. Without treatment, chancroid lesions are "slowly destructive" and only heal with scarring. [PPID, p. 1446-7] Chancroid facilitates the transmission of HIV. About 10% of patients are co-infected with syphilis. [ABX Guide] Rarely, chancroid causes Parinaud's oculoglandular syndrome. [Guerrant, p. 1005]

DIFFERENTIAL DIAGNOSIS:
Patient with probable diagnosis has one or more painful ulcers, negative darkfield microscopy for syphilis or negative syphilis serology >7 days after ulcer onset, +/- regional lymphadenopathy, and negative HSV test of ulcer exudate; 1/3 of patients have painful ulcer and tender lymph nodes; When also have suppurative lymph nodes, then almost pathognomonic; [ABX Guide]
DIAGNOSTIC
Culture (special media) <80% sensitive; PCR 95-98% sensitive, but no FDA-approved test; School of fish on Gram stain; Diagnosis (CDC): isolation of H. ducreyi from lesions; Probable: genital ulcer (+) adenopathy (+) syphilis & HSV tests (-); [5MCC-2020]
SCOPE
Common in tropical and subtropical regions with occasional outbreaks in the USA; [CCDM] Rarely seen in the USA except in occasional urban outbreaks; [PPID, p. 1447]
SIGNS & SYMPTOMS
  • H lymphadenopathy
  • O conjunctivitis, acute
  • O oculoglandular syndrome
  • S lymphadenitis, acute
  • S papules or plaques
  • S pustule
  • S ulcer of skin
  • *erythema nodosum
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Skin or Mucous Membranes (Includes Conjunctiva), Sexual Contact
RESERVOIR
Human
RISK FACTORS
REFERENCES FOR CASES/YEAR
1. (US) Published in MMWR 2011; Use correction factor of 10 for reported diseases: 8 X 10 = 80;
2. (Global) Prevalent in Africa, Asia, Latin America, and US poor; [Gorbach, p. 118] In the 1990s, WHO estimated annual global prevalence = 4-6 million; [Cecil, p. 1916]