In 2006, the World Health Organization (WHO) released revised criteria for clinical staging of HIV disease in adults and adolescents. These criteria allow physicians in resource poor countries to determine the appropriate time to begin antiretroviral treatment. In many areas of the world, physicians do not have access to labs where they can perform CD4 and viral load tests, which are used in developed countries to determine an individual’s disease progression.
Criteria for Stage I
During the first stage of HIV, an individual generally has flu like symptoms which last for a week or two. WHO provides the following criteria for placing a patient in this stage:
- Asymptomatic
- Persistent generalized lymphadenopathy (the swelling or enlargment of the lymph nodes).
Criteria for Stage II
In stage II, many people are completely asymptomatic, but others demonstrate a number of physical symptoms that healthcare providers can use to stage the patient. WHO criteria for this stage include the following:
- Moderate unexplained weight loss
- Recurring respiratory tract infections
- Herpes Zoster (shingles)
- Angular cheilitis (lesions at the corner of the mouth)
- Recurring oral ulceration
- Papular pruritic eruptions (skin rash possibly related to insect bites)
- Seborrhoeic dermatitis (a skin disorder that causes scaly, itchy, flaky skin)
- Fungal nail infections.
Criteria for Stage III
In stage III, HIV patients begin to exhibit more serious symptoms. This is also when opportunistic infections begin to take advantage of the weakened immune system. WHO criteria for placing a patient in this stage include the following:
- Unexplained severe weight loss
- Unexplained chronic diarrhea lasting for longer than one month
- Unexplained persistent fever, either intermittent or constant
- Persistant oral candidiasis (yeast infection of the mouth)
- Oral hairy leukoplakia (a white patch on the side of the tongue with a hairy appearance)
- Pulmonary tuberculosis
- Severe bacterial infections (for example, pneumonia, meningitis, and empyema)
- Acute necrotizing ulcerative stomatitis (inflammation of the stomach mucous lining), gingivitis (inflammation of the gums), or periodontitis (inflammation of the tissue that supports the teath)
- Unexplained anemia (lack of hemoglobin the blood cells), neutropenia (low number of a certain type of white blood cell called neutrophil), and/or chronic thrombocytopenia (low platelet count).
Criteria for Stage IV (AIDS)
In stage IV, a patient is considered to have progressed from HIV to AIDS. This stage is characterized by more severe symptoms and an even greater number of opportunistic infections. WHO criteria for this stage include the following:
- HIV wasting syndrome
- Pneumocystis pneumonia (pneumonia caused by a yeast-like fungus)
- Recurrent severe bacterial pneumonia
- Chronic herpes simplex infection
- Esophageal candidiasis (yeast-like infection of the esophagus)
- Extrapulmonary tuberculosis
- Kaposi sarcoma (a tumor caused by human herpesvirus 8)
- Cytomegalovirus infection (an infection caused by human herpesvirus 5)
- Central nervous system toxoplasmosis (a parasite affecting the central nervous system, including brain)
- HIV encephalopathy (a brain disorder)
- Extrapulmonary cryptococcosis including meningitis (fungal diseases)
- Disseminated non-tuberculous mycrobacteria infection
- Progressive multifocal leukoencephalopathy (the reactivation of a common virus in the central nervous system)
- Chronic cryptosporidiosis (a parasitic disease)
- Chronic isosporiasis (a parasitic intestinal disease)
- Disseminated mycosis (a fungus that causes infection)
- Recurrent septicemia (also known as blood poisoning)
- Lymphoma (cerebral or B cell non-Hodgkin)
- Invasive cervical carcinoma
- Atypical disseminated leishmaniasis (a parasite transmitted by the sand fly)
- Symptomatic HIV-associated nephropathy or HIV-associated cardiomyopathy.
Please see The Four Stages of HIV Infection for more information on each of these clinical stages.
