A 35-year-old man comes to the physician because of a skin rash. Six months ago, the patient was treated in the hospital for Pneumocystis pneumonia and painful oral ulcers. He takes no medications but drinks alcohol frequently and uses recreational drugs. Physical examination demonstrates a widespread rash consisting of lesions similar to that shown in the image below. Which of the following is the most likely cause of this patient's current condition?

Question

A 35-year-old man comes to the physician because of a skin rash.  Six months ago, the patient was treated in the hospital for Pneumocystis pneumonia and painful oral ulcers.  He takes no medications but drinks alcohol frequently and uses recreational drugs.  Physical examination demonstrates a widespread rash consisting of lesions similar to that shown in the image below.  Which of the following is the most likely cause of this patient's current condition?

Quizplus · Accepted Answer

11ec160b_38f8_985a_9249_bf115f299bcd_MD0001_00 Pneumocystis pneumonia and painful oral ulcers in a patient with a history of recreational drug use is highly suggestive of HIV infection, a diagnosis further supported by the presence of Kaposi sarcoma (KS). The most common tumor in HIV-positive individuals, KS presents as multiple red, purple, or brown papules or plaques that first appear on the lower extremities before spreading proximally. KS lesions can also develop on the mucosal membranes of the face and genitals. In late-stage disease, lesions spread to the lungs and gastrointestinal tract. Histologic examination shows a spindle-shaped endothelial cell proliferation with slit-like vascular spaces, red blood cell extravasation, and inflammation. KS is strongly associated with both HIV and human herpesvirus type 8 (HHV-8); HHV-8 DNA has been isolated in the neoplastic cells of KS. HHV-8 infects vascular and lymphatic endothelial cells, causing their differentiation into a mixed phenotype thought to increase oncogenic potential. The HHV-8 genome contains several viral oncogenes that inhibit cell cycle regulation and apoptosis, thus promoting tumorigenesis. (Choice A) Exposure to arsenic is associated with development of skin (squamous cell carcinoma), liver (angiosarcoma), lung, and bladder cancers. (Choice B) Cytomegalovirus infection in HIV-positive patients typically causes esophagitis, colitis, and retinitis. It can also cause a mononucleosis-like illness with rash, which usually has a maculopapular/morbilliform appearance. (Choice C) Like HHV-8, Epstein-Barr virus also belongs to Herpesviridae. Epstein-Barr virus causes infectious mononucleosis and is associated with Burkitt lymphoma, nasopharyngeal carcinoma, and CNS lymphoma in HIV-positive patients. (Choice D) Chronic infection with hepatitis C virus increases the risk of developing hepatocellular carcinoma. (Choice E) Herpes simplex virus type 1 typically causes oral vesicles and ulcers, which may be more severe in patients with HIV. It can also cause esophagitis, encephalitis, and keratitis. (Choice G) Human papillomavirus strains 16, 18, 31, and 33 are associated with squamous cell carcinoma of the cervix, vulvae, anus, and oropharynx. (Choice H) Human T-cell leukemia virus type1 belongs to Retroviridae. It causes T-cell leukemia, especially in patients originating from southern Japan. (Choice I) Ultraviolet radiation (eg, sunlight, tanning bed) can cause skin cancers, including melanoma, squamous cell carcinoma, and basal cell carcinoma. (Choice J) Vinyl chloride exposure is associated with development of hepatic angiosarcoma. Educational objective: Kaposi sarcoma typically presents as red, purple, or brown papules and plaques on the extremities and mucous membranes of HIV-positive patients. This vascular tumor is strongly associated with human herpesvirus type 8.

A 35-Year-Old Man Comes to the Physician Because of a Skin