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A 45-year-old man comes to the clinic with skin lesions over his trunk, abdomen, and face. The patient also notes significant weight loss over the last six months. Past medical history is significant for gastroesophageal reflux disease, alcoholic cirrhosis, and esophageal varices. The patient was admitted two months ago for bleeding esophageal varices and underwent endoscopic variceal ligation. The patient is sexually active with men and women and uses condoms inconsistently. The patient uses intravenous drugs, including morphine, and consumes alcohol regularly. Temperature is 36.6°C (98.0°F), pulse is 99/min, respirations are 20/min, and blood pressure is 120/75 mmHg. Physical examination reveals anterior and posterior cervical lymphadenopathy. Oral examination reveals white mucosal plaques that cannot be scraped off easily. Skin lesions on the right arm are depicted below. This patient’s clinical presentation suggests which of the following underlying conditions?
Wikimedia Commons
By Unknown author - National Cancer Institute, AV-8500-3620, Public Domain      

External References

First Aid








AIDS (acquired immunodeficiency syndrome)

AIDS retinitis p. 162

Cytomegalovirus (CMV)

AIDS retinitis p. 162

Eye disorders

AIDS retinitis p. 162


AIDS retinitis p. 162

Kaposi sarcoma p. 490

AIDS and p. 180


Content Reviewers

HIV, or human immunodeficiency virus, is a virus that targets cells in the immune system.

Over time, the immune system begins to fail which is called immunodeficiency, and this increases the risk of infections and tumors that a healthy immune system would usually be able to fend off.

These complications are referred to as AIDS, or acquired immunodeficiency syndrome.

Now there are two distinct types of HIV—HIV-1 and HIV-2.

HIV-1 is the more commonly associated with AIDS in the US and worldwide, HIV-2 is more rare, and typically restricted to areas in western Africa and southern Asia.

HIV-2 is so uncommon that “HIV” almost always refers to HIV-1.

Alright HIV targets CD4+ cells, meaning cells that have this specific molecule called CD4 on their membrane. Macrophages, T-helper cells, and dendritic cells are all involved in the immune response and all have CD4 molecules; therefore they can be targeted by HIV.

The CD4 molecule helps these cells attach to and communicate with other immune cells, which is particularly important when the cells are launching attacks against foreign pathogens.

So this little molecule is pretty important for our immune system, but it’s also extremely important for HIV. HIV targets and attaches to the CD4 molecule via a protein called gp120 found on its envelope.

HIV then again uses gp120 to attach to another receptor, called a co-receptor.

HIV needs to bind to both the CD4 molecule and a coreceptor to get inside the cell.

The most common co-receptors that HIV uses are the CXCR4 co-receptor, which is found mainly on T-cells, or the CCR5 co-receptor which is found on T-cells, macrophages, monocytes, and dendritic cells.


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