Chancroid ( ) is a bacterial sexually transmitted infection characterized by painful sores on the genitalia. Chancroid is known to spread from one individual to another solely through sexual contact. However, there have been reports of accidental infection through the hand.
Signs and symptoms
These are only local and no systemic manifestations are present. The ulcer characteristically: Ranges in size dramatically from 3 to 50 mm (1/8 inch to 2 inches) across Is painful Has sharply defined, undermined borders Has irregular or ragged borders, described as saucer-shaped. Has a base that is covered with a gray or yellowish-gray material Has a base that bleeds easily if traumatized or scraped Painful swollen lymph nodes occur in 30–60% of patients. Dysuria (pain with urination) and dyspareunia (pain with intercourse) in females
About half of infected men have only a single ulcer. Women frequently have four or more ulcers, with fewer symptoms. The ulcers are typically confined to the genital region most of the time.
The initial ulcer may be mistaken as a "hard" chancre, the typical sore of primary syphilis, as opposed to the "soft chancre" of chancroid.
Approximately one-third of the infected individuals will develop enlargements of the inguinal lymph nodes, the nodes located in the fold between the leg and the lower abdomen.
Half of those who develop swelling of the inguinal lymph nodes will progress to a point where the nodes rupture through the skin, producing draining abscesses. The swollen lymph nodes and abscesses are often referred to as buboes.
Complications
Extensive lymph node inflammation may develop. Large inguinal abscesses may develop and rupture to form draining sinus or giant ulcer. Superinfection by Fusarium and Bacteroides. These later require debridement and may result in disfiguring scars. Phimosis can develop in long-standing lesion by scarring and thickening of foreskin, which may subsequently require circumcision.
Sites For Chancroid Lesions
Males
Internal and external surface of prepuce. Coronal sulcus Frenulum Shaft of penis Prepucial orifice Urethral meatus Glans penis Perineum area
Females
Labia majora is most common site. "Kissing ulcers" may develop. These are ulcers that occur on opposing surfaces of the labia. Labia minora Fourchette Vestibule Clitoris Perineal area Inner thighs
Causes
Chancroid is a bacterial infection caused by the fastidious Gram-negative streptobacillus Haemophilus ducreyi. This pathogen is highly infectious. It is a disease found primarily in developing countries, most prevalent in low socioeconomic groups, associated with commercial sex workers.
Chancroid, caused by H. ducreyi has infrequently been associated with cases of Genital Ulcer Disease in the US but has been isolated in up to 10% of genital ulcers diagnosed from STD clinics in Memphis and Chicago.
Infection levels are very low in the Western world, typically around one case per two million of the population (Canada, France, Australia, UK and US). Most individuals diagnosed with chancroid have visited countries or areas where the disease is known to occur frequently, although outbreaks have been observed in association with crack cocaine use and prostitution.
Chancroid is a risk factor for contracting HIV, due to their ecological association or shared risk of exposure, and biologically facilitated transmission of one infection by the other. Approximately 10% of people with chancroid will have a co-infection with syphilis and/or HIV.
Pathogenesis
H. ducreyi enters skin through microabrasions incurred during sexual intercourse. The incubation period of H. ducreyi infection is 10 to 14 days after which there is progression of the disease. A local tissue reaction leads to development of erythematous papule, which progresses to pustule in 4–7 days. It then undergoes central necrosis to ulcerate.
Diagnosis
Variants
Some of clinical variants are as follows.
Laboratory findings
From bubo pus or ulcer secretions, H. ducreyi can be identified using special culture media; however, there is a <80% sensitivity. PCR-based identification of the organisms is available, but none in the United States are FDA-cleared. Simple, rapid, sensitive and inexpensive antigen detection methods for H. ducreyi identification are also popular. Serologic detection of H. ducreyi uses outer membrane protein and lipooligosaccharide. Most of the time, the diagnosis is based on presumptive approach using the symptomatology which in this case includes multiple painful genital ulcers.