USMLE® Step 1 style questions USMLE
A 25-year-old man comes to the office because of a growth in his right leg. Patient has HIV+ and patient says that at first, the lesion was flat, however, it has become raised over the past year. He says that an additional lesion has appeared in his right hip and another in his flank. Physical examination shows a large, raised, well-circumscribed, purple lesion in his right upper thigh. A biopsy of one of the lesions shows a lymphocytic infiltrate. Which of the following is the most likely etiology of this patient's condition?
Content Reviewers:Rishi Desai, MD, MPH
Vascular tumors are tumors of the blood vessels, and there actually a lot of different types, so this is just a quick overview of three types of tumors: Kaposi sarcoma, hemangioma, and angiosarcoma. Kaposi sarcoma is a malignant vascular tumor that is linked with an infection of the human herpesvirus 8 (otherwise known as HHV-8). And it’s a cancer of the blood vessel endothelial cells. This virus is thought to get inside of the cells, and cause the cells to replicate uncontrollably. This type of cancer is seen in people who have suppressed immune systems. That’s why it’s one of the common diseases you’re at risk of getting if you have AIDS, and is a complication of organ transplant patients.
The most common symptoms of Kaposi sarcoma affect the skin, causing purple and red lesions. These lesions look somewhat like a bruise, but unlike a bruise they don’t blanch, or turn pale, when pressed. That’s because a Kaposi sarcoma has blood filled blood vessels whereas bruises are caused by blood leaking outside of blood vessels into the skin. Initially these lesions start off flat, but over time they may become raised and more painful. In people who have a compromised immune systems, the disease can also cause lesions in other tissues like the mouth, the nose, the throat, the lymph nodes, the lungs, and the gastrointestinal tract.
You can sometimes treat affected skin by surgically removing it or freezing it using cryotherapy, however treating the disease in immunocompromised patients is a little more difficult. If someone’s immune system is compromised because of drugs such as corticosteroids, it might be necessary to adjust immunosuppressants and allow the immune system to recover. It’s a lot harder to treat the disease in an AIDS patient whose immune system is severely compromised, so antiretroviral therapy is commonly used by patients to restore immunity. Radiation and chemotherapy are also treatment options.
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