HIV/AIDS Module 8 Lecture Review

Flashcards covering the pathophysiology, risk factors, clinical stages, prevention (PrEP/PEP), and diagnostic testing for HIV/AIDS as presented in the Module 8 lecture.

Acquired immunodeficiency syndrome (AIDS)

The final stage of infection with Human Immunodeficiency Virus (HIV) characterized by severe immunodeficiency, opportunistic infections, and cancers.

HIV (Human Immunodeficiency Virus)

A retrovirus that carries out RNA, transmitted by direct contact with infected blood and body fluids, which attacks CD4 immune cells.

Antiretroviral therapy (ART)

A treatment that combines the administration of three medications to slow down the virus, stop it from making copies, and keep the immune system stronger.

Reverse transcriptase

An enzyme used by HIV to change its RNA into DNA after entering a cell.

Seroconversion

The process where the immune system starts making antibodies against HIV, typically occurring 6 weeks to 6 months after infection.

CD4 (Helper T cells)

The primary target of HIV; these cells act as coordinators of the immune system by helping B cells make antibodies and helping kill infected cells.

Window period

The time after infection when antibodies are not yet detectable, lasting about 6 weeks to 6 months, during which a person is infectious despite a negative test.

Autologous transfusion

A preventive measure involving using the blood patients themselves donate before an anticipated surgery.

Pre-exposure prophylaxis (PrEP)

An HIV prevention method for HIV-negative people at high risk involving a daily pill taken before exposure to help prevent infection.

Truvada

A PrEP medication consisting of a combination of tenofovir and emtricitabine.

Descovy

A PrEP medication consisting of a combination of emtricitabine and tenofovir alafenamide.

Post-exposure prophylaxis (PEP)

An HIV prevention treatment taken after possible exposure (e.g., needle stick, sexual assault) that must start within $72$ hours and continue for $28$ days.

Lymphadenopathy

The enlargement of two or more lymph nodes outside the inguinal chain following HIV infection.

AIDS dementia complex

Also called HIV-associated dementia, it is an infection of the brain by HIV that affects cognitive, motor, and behavioral functions.

Distal symmetric polyneuropathy (DSP)

The most common nerve problem in HIV, affecting about $50 \%$ of patients, characterized by burning pain, tingling, or aching mainly in the feet and legs.

Guillain-Barré–like polyneuropathy

An inflammatory nerve disease seen in HIV patients characterized by progressive muscle weakness and paralysis.

Stage 1 (Early HIV)

A clinical stage where the person is very contagious, the CD4 count is normal or high, and there are usually no symptoms or only swollen lymph nodes.

Stage 2 (Chronic / Latent HIV)

A clinical stage where the virus is present but symptoms are mild, and the CD4 count starts to drop to the range of $200$ to $500$.

Stage 3 (AIDS)

A clinical stage where the immune system is very weak, indicated by a CD4 count below $200$ or the appearance of a serious illness or cancer.

Stage 4 (Very advanced AIDS)

A clinical stage characterized by life-threatening illnesses, severe wasting, brain infections, and various cancers like Kaposi sarcoma.

Normal CD4 cell count

A count higher than $1000/mm^3$.

Immunodeficiency CD4 threshold

A CD4 count below $500/mm^3$.

Pneumocystis Jiroveci Pneumonia

A serious lung infection caused by a common fungus that is dangerous when immunity is low, resulting in fever, dry cough, and shortness of breath.

ELISA (Enzyme-Linked Immunosorbent Assay)

The most widely used screening test that detects HIV antibodies rather than the virus itself; positive results must be confirmed.

HIV-1/HIV-2 Differentiation Immunoassay

The preferred confirmatory test over Western blot for a positive 4th-generation HIV test, providing results in less than $20$ minutes.

NAT (Nucleic Acid Test)

An expensive test that detects HIV in blood directly rather than antibodies, capable of detection within $1$ to $4$ weeks after exposure.