A 21-year-old man comes to the urgent care clinic with a lesion on his penis. He noticed a painful ulcer on the right side of his penis 4 days ago and it has progressively increased in size since then. The patient has had no dysuria, hematuria, or penile discharge. He is a tourist visiting New York City from Botswana. He is HIV-positive and is sexually active. The patient currently takes no medications. He appears comfortable and is afebrile. On genitourinary examination, there is a 1.5-cm ulceration on the right side of the base of the penis; the lesion is very tender and soft; has irregular, ragged borders; and is covered with grey exudate. There is a palpable, tender, enlarged inguinal lymph node in the right groin. The examination is otherwise unremarkable. A scraping of the ulcer is performed. Polymerase chain reaction testing for herpes simplex virus is negative, and darkfield microscopy reveals no organisms. Which of the following is the most likely diagnosis?
Characteristics of ulcerative sexually transmitted diseases | |||
Disease | Causative agent | Features of primary lesion | Initial lesion painful? |
Chancroid | Haemophilus ducreyi |
| Yes |
Genital herpes | Herpes simplex virus 1 & 2 |
| Yes |
Granuloma inguinale (donovanosis) | Klebsiella granulomatis |
| No |
Syphilis | Treponema pallidum |
| No |
Lymphogranuloma venereum | Chlamydia trachomatis |
| No |
Chancroid is caused by Haemophilus ducreyi, a gram-negative bacterium transmitted through sexual contact. It presents as one or more deep, painful ulcers (you "do cry" with H ducreyi) with ragged borders that are associated with a grey exudate and inguinal lymphadenopathy. On Gram stain, the organism appears as curved, gram-negative rods, often in a clumping pattern. The disease is relatively uncommon in the United States but has much higher prevalence in sub-Saharan Africa, Latin America, and regions of Asia.
(Choice B) Condyloma acuminata, or genital warts, are caused by the human papillomavirus. They present as skin-colored, white, or grey verrucous and filiform papules usually in the penile glans and shaft in men and the vulvovaginal and cervical areas in women.
(Choice C) In immunocompromised patients, manifestations of cytomegalovirus infection include febrile illness, pneumonitis, retinitis, esophagitis, and colitis.
(Choice D) Gonorrhea and chlamydia most commonly present with dysuria and penile discharge, neither of which is present in this patient. Although it may be appropriate to perform testing for other sexually transmitted infections, gonorrhea would be an unlikely explanation for this patient's painful genital ulcer.
(Choice E) Granuloma inguinale is characterized by painless, extensive ulcerative lesions, typically without lymphadenopathy.
(Choice F) Molluscum contagiosum is a contagious disease caused by infection with a DNA poxvirus. Lesions are smooth, skin-colored, firm, somewhat pearly papules that measure about 2-6 mm and often have a central umbilication.
(Choice G) Primary syphilis commonly presents as a characteristically painless single genital ulcer called a chancre. The diagnosis is established by identification of the organisms on darkfield microscopy, serologic testing, or syphilis antibody testing. Secondary syphilis is often characterized by systemic symptoms, lymphadenopathy, grey mucous patches, raised grey genital papules (condylomata lata), and a diffuse rash involving the palms and soles.
(Choice H) Penile squamous cell cancer can present as lumps or ulcers, sometimes with adenopathy. However, the lesions are typically painless, and average age at presentation is 50.
Educational objective:
Chancroid, due to Haemophilus ducreyi, presents as deep, painful (you "do cry" with H ducreyi) ulcers with ragged borders that are associated with a grey exudate and inguinal lymphadenopathy. Diagnosis is established by Gram stain and culture of the organism from a scraping of the ulcer base.