HIV Classification and Staging

Do I have HIV or AIDS?

Lots of confusion surrounds the question, Is it HIV or AIDS.  For some HIV+ people who are savvy about HIV, whether because they read everything they can get their hands on or have had friends die of an AIDS-related illness, the difference is quite important and they ask me at the first clinic visit whether they have HIV or AIDS.  Other newly diagnosed people don’t know the difference and they don’t care--at this point, they are just trying to  get used to having HIV and everything this new diagnosis means to their life.

  

This is what you must know.  Every person who has been infected with HIV has HIV--however not everyone with HIV has AIDS.  The rule is: Once someone with HIV reaches a CD4 count of less than 200 (or a CD4 percentage less than 14%), that person is classified as having AIDS.  There is one other way to be classified as having AIDS.  If a person with HIV gets an AIDS- related disease, like tuberculosis or cervical cancer, that person is also classified as having AIDS, no matter what their CD4 count.  

Here is an example:  At her latest check-up, Mary had a CD4 count of 580 with a CD4 percentage of 31%.  Her CD4 count has never been less than 500.  Last year, however, Mary was diagnosed with tuberculosis.  Mary is classified as having AIDS.  

Once the disease is classified as AIDS, it is always classified AIDS.  The classification never goes back to HIV alone. 

There are two HIV classification systems: the United States Centers for Disease Control and Prevention (CDC) Classification System and the World Health Organization (WHO) Clinical Staging and Disease Classification System.   In the United States and other developed countries, medical health providers use the CDC system.   This is because the CDC classification system relies heavily on the CD4 count.  Other countries may not have the ability to use the CD4 count to classify their HIV patients, whether because their HIV+ persons do not live near laboratories that can test their blood or because of limited money to perform the CD4 count test.  These countries use the WHO Staging System which relies more heavily on looking at the illnesses or conditions the HIV+ person may have.  

Why do we need to classify HIV?

We put HIV disease in a classification system so that we can research, understand, track, monitor, and treat the disease.  Medical providers who receive government money to treat the disease must provide information to the government regarding how HIV is being spread, who is getting HIV, how HIV is being treated.    

Although each individual is unique, HIV experts know that HIV disease follows a certain pattern in just about everyone.  For instance, we know that if your CD4 count is less than 50 and you are not on medicine, you have a pretty good chance of getting sick from an AIDS-related illness in the near future.  We know that without treatment, your CD4 count will most likely decline over the years--not increase.  These patterns are what enables HIV positive people to be classified into certain categories.  Classifying HIV ensures that when people all over the world are discussing HIV, they are speaking the same language--in other words, they are speaking the language of HIV.

The two classification systems allow HIV experts and non-experts to monitor the disease in their populations.  If a city leader sees that there is a large amount of new HIV cases in a certain area of the city, this person can send out experts to examine why the HIV outbreak is occurring in this section of the country.    

One important reason for the HIV classification system is to provide medical providers and HIV+ people with the information they need about where the HIV+ person is in the course of HIV disease.  Someone with AIDS knows that medicines are needed right now, whereas someone who is classified as “asymptomatic HIV” (HIV without symptoms of the disease) knows that they most likely will have some time before medicines need to be started.  

Since we use the CDC classification system in this country, I will not include the WHO Staging System in this blog.  The following tables contain the CDC guidelines to classify HIV.  

The CDC Classification System for HIV-infected Adults and Adolescents

CD4 Cell Categories	Clinical Categories
	A Asymptomatic (no symptoms), Acute HIV (new HIV infection), or Persistent Generalized Lymphadenopathy (painless swollen glands more than 3 months)	B  Symptomatic Conditions, Not Category A or C (See Category B Symptomatic Conditions table below)	C AIDS-Indicator Conditions (See Category C AIDS-Indicator Conditions table below)
Stage 1  CD4 500 or more (or CD4 percentage 29 % or more)	A1	B1	C1
Stage 2  CD4 200-499 (or CD4 percentage 14-28%)	A2	B2	C2
Stage 3  CD4 less than 200 (or CD4 percentage less than 14%)	A3	B3	C3

Example: John has a CD4 of 350--we know that puts him in CDC Stage 2 HIV disease.  However we need to know more about John in order to classify him in stage A, B, or C. Let’s look at the next table.

CDC Classification System:  Category B Symptomatic Conditions

Conditions occurring in an HIV-infected adolescent or adult that meet at least 1 of the following criteria:

They are due to HIV infection or indicate an immune system problem. The course of the disease or the management of the disease is complicated by HIV.

Examples include, but are not limited to, these: Bacillary angiomatosis Oropharyngeal candidiasis ( oral thrush) Vulvovaginal candidiasis (vaginal yeast infection), persistent or resistant Pelvic inflammatory disease Cervical dysplasia (abnormal cells of the cervix)--moderate or severe--or cervical carcinoma in situ (cervical cancer that has not spread) Oral hairy leukoplakia (white pearly-looking patches on tongue) Constitutional symptoms, such as fever or diarrhea lasting more than one month Peripheral neuropathy (pain, numbness, or tingling in hands or feet) Herpes zoster (shingles), at least two episodes

Example: John, our example from above, whose CD4 is 350, has no symptoms of HIV; therefore he is classified as being in Stage A2.  Several months later, John develops oral thrush--however, his CD4 goes up to 400.  He is now classified as Stage B2.  

CDC Classification System: Category C AIDS-Indicator Conditions

Bacterial pneumonia, recurrent (2 or more episodes in 12 months) Bacterial infections, multiple or recurrent--children less than 13 years old only Candidiasis (white cottage cheese-looking patches) of the bronchi, trachea, or lungs (extends into the respiratory system) Esophageal candidiasis (white cottage cheese-looking patches that extend past the throat and into the esophagus) Cervical carcinoma, invasive, confirmed by biopsy (cervical cancer that has spread) Coccidioidomycosis, disseminated or extrapulmonary (infection has spread into more than one body system or is outside of the lungs Cryptococcosis, extrapulmonary (infection is outside of the lungs) Cryptosporidiosis, chronic intestinal (lasts more than one month) Cytomegalovirus (CMV) disease (other than liver, spleen, or lymph nodes) Cytomegalovirus retinitis(with loss of vision), an eye-infection Encephalopathy, HIV-related (a brain infection) Herpes simplex (HSV), chronic. Ulcers must last more than one month or involving the bronchial tubes, lungs, or esophagus Histoplasmosis, disseminated or extrapulmonary (infection has spread into more than one body system or is outside of the lungs). Isosporiasis, chronic intestinal (lasting more than one month) Kaposi sarcoma Lymphoma, Burkitt Lymphoma, immunoblastic Lymphoma, primary, of brain Mycobacterium avium complex (MAC) or Mycobacterium kansasii, disseminated or extrapulmonary Mycobacterium tuberculosis (MTB), pulmonary or extrapulmonary (in or outside of the lungs) Mycobacterium, other species or unidentified species, disseminated or extrapulmonary (involving more than one body system and outside of the lungs) Pneumocystis jiroveci (formerly called pneumocystis carinii), or PCP Progressive multifocal leukoencephalopathy (PML) Salmonella septicemia, recurrent (nontyphoid)--more than one episode of this bacterial blood infection Toxoplasmosis of the brain Wasting syndrome due to HIV (weight loss, without dieting, of more than 10% of the person’s normal weight before the person became HIV+) associated with either chronic diarrhea (two or more loose stools a day for more than one month) or chronic weakness and documented fever (health care provider must note the fever in the chart) for a month or more.

Now, look over this list of AIDS-related diseases.  These are diseases you and your friends and family most likely never heard of.  Most of the names of the diseases seem strange and are difficult to pronounce.  No one dies of AIDS itself.  Most likely, if the person does not take HIV medicines, the person with advanced AIDS (CD4 less than 50)  will die of one of the above AIDS-related conditions or an HIV- related complication.   All of these diseases listed in the last table are called opportunistic infections.   We will discuss this very important topic in later chapters.