Hiv Pathophysiology

Pathophysiology of the human immunodeficiency virus
Nancy R. Calles, MSN, RN, PNP, ACRN, MPH Desiree Evans, MD, MPH DeLouis Terlonge, MD

Objectives
1. 2. 3. 4. 5. Provide an overview of the healthy immune system. Describe the human immunodeficiency virus (HIV). Describe the major components of the HIV life cycle. Identify the various HIV types and subtypes. Discuss HIV’s effects on the immune system.

Overview
The human immunodeficiency virus (HIV) is a retrovirus belonging to the family of lentiviruses. Retroviruses can use their RNA and host DNA to make viral DNA and are known for their long incubation periods. Like other retroviruses, HIV infects the body, has a long incubation period (clinical latency), and ultimately causes the signs and symptoms of disease, here AIDS. HIV causes severe damage to the immune system and eventually destroys it by using the DNA of CD4+ cells to replicate itself. In that process, the virus eventually destroys the CD4+ cells.

Key Points
1. The immune system protects the body by recognizing invading antigens on pathogens (bacteria, viruses, fungi, and parasites) and reacting to them. 2. T lymphocytes, or T cells, regulate the immune system and destroy antigens. 3. HIV continuously uses new host cells to replicate itself. 4. The HIV life cycle includes six phases: binding and entry, reverse transcription, integration, replication, budding, and maturation. 5. Once HIV is in the circulatory system, it targets the CD4+ lymphocyte. 6. Two types of HIV cause AIDS: HIV type 1 (HIV-1) and HIV-2. 7. Primary infection refers to the time when HIV first enters the body. 8. Clinical latency refers to the time before onset of symptoms and complications in the HIV-infected individual. In HIV-infected adults, this phase may last 8-10 years. 9. Early signs and symptoms of HIV can include candidiasis, lymphadenopathy, cervical carcinoma, herpes zoster, and peripheral neuropathy. 10. Late signs and symptoms of HIV and AIDS-defining illnesses can

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