What is the full medical name for AIDS? What are its diagnostic criteria?

Okay, no problem. Let's break this down in plain terms.

What is the medical full name for AIDS?

The medical full name for AIDS is Acquired Immunodeficiency Syndrome.

In English, it's Acquired Immunodeficiency Syndrome, hence the abbreviation AIDS.

We can understand this term by breaking it down, which makes it much clearer:

Acquired: This means the condition isn't something you're born with, it's not inherited. Instead, it's something you "acquire" later in life. It's typically contracted from outside sources through specific routes (like blood, sexual contact, etc.).
Immunodeficiency: This is the core problem. "Immune" refers to the body's "defense force" responsible for fighting off bacteria and viruses. "Deficiency" means this force has a major problem; its fighting capability becomes very, very weak, even to the point where the whole system is nearly paralyzed.
Syndrome: This term sounds technical, but it essentially means "a collection of symptoms." That's because it doesn't refer to one specific disease. Instead, when the "defense force" collapses, all sorts of bacteria, viruses, and even cancers that normally wouldn't cause big problems seize the opportunity to wreak havoc, leading to a wide variety of complex illnesses. So, it's a comprehensive set of manifestations.

Simply put: AIDS = When the body's immune system is destroyed by a virus (HIV), leading to a bunch of complex, varied illnesses.

What are the diagnostic criteria for AIDS?

First and foremost, the crucial prerequisite must be understood: Only someone infected with the Human Immunodeficiency Virus (HIV) can potentially develop AIDS. HIV is the virus; AIDS is the condition after the disease fully manifests. They are two different things.

Therefore, a person with AIDS (Acquired Immunodeficiency Syndrome) must be an HIV-infected individual. Building on this foundation, doctors use the following two main criteria to determine if the person has progressed to the "AIDS stage". Meeting either one usually qualifies:

Based on the "Immune Defense Force" Count (Laboratory Criterion):

Our immune system has a crucial "commander-in-chief" cell called the CD4+ T-lymphocyte.
- In a healthy person, the CD4 cell count is typically between 500-1600 per cubic millimeter (mm³) of blood.
- When the HIV virus continuously attacks these cells, reducing the count to less than 200 cells/mm³, it signifies severe damage to the immune system and a state of very low resistance. At this point, even if the person has no obvious symptoms, they can be medically diagnosed as having entered the AIDS stage.
Based on "Body Manifestations" (Clinical Criterion):

If an HIV-infected individual whose CD4 count hasn't necessarily dropped below 200 develops certain specific, serious illnesses that typically occur only when the immune system is extremely weak, they can also be diagnosed with AIDS.

These specific illnesses are called "AIDS-defining conditions". They act like "indicators" for the onset of AIDS. Examples include:
- Pneumocystis pneumonia (a specific type of pneumonia)
- Kaposi's sarcoma (a cancer of the skin or internal organs)
- Recurrent severe bacterial infections
- Candidiasis of the esophagus
- And many other opportunistic infections (viral, fungal) and related cancers.
This list is extensive and includes serious infections that attack when the body is vulnerable. Developing any one of these conditions essentially signals that the immune defenses have been breached.

Simple Summary

HIV infection: Is the cause. The virus has entered the body. With medication, it can often be well-controlled, preventing the virus from causing major problems.

AIDS: Is the consequence. It happens when the virus is not adequately controlled and devastates the immune system, pushing the body into a very dangerous state.

Therefore, the current medical goal is to detect HIV infection early and initiate antiretroviral therapy when a person is still just an HIV carrier. This keeps the virus suppressed at very low levels, protects CD4 cells, and allows the person to live a normal life, preventing progression to the AIDS stage altogether.