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aids

AIDS

see also:

introduction

  • AIDS is diagnosed when the immune system of a person infected with HIV becomes severely compromised (measured by CD4 cell count) and⁄or the person becomes ill with an opportunistic infection or illness.
  • without treatment, AIDS usually develops 8 to 10 years after initial HIV infection;
  • with early HIV diagnosis and treatment, this may be delayed by many years.

HIV stages

  • in 2008 the CDC moved towards a HIV staging model to classify the disease1):
    • HIV infection, stage 1:
      • No AIDS-defining condition and either CD4+ T-lymphocyte count of >500 cells/µL or CD4+ T-lymphocyte percentage of total lymphocytes of >29.
    • HIV infection, stage 2:
      • No AIDS-defining condition and either CD4+ T-lymphocyte count of 200–499 cells/µL or CD4+ T-lymphocyte percentage of total lymphocytes of 14–28.
    • HIV infection, stage 3 (AIDS):
      • see AIDS definition
    • HIV infection, stage unknown:
      • No information available on CD4+ T-lymphocyte count or percentage and no information available on AIDS-defining conditions.

AIDS definition

adults and adolescents

CD4+ T-cell count below 200 cells/µl

OR

CD4+ T-cell percentage of total lymphocytes of less than 14%

OR

presence of an AIDS-defining illness in a person with HIV infection

Documentation of an AIDS-defining condition supersedes a CD4+ T-lymphocyte count of >200 cells/µL and a CD4+ T-lymphocyte percentage of total lymphocytes of >14.

children 18 months to 13 years

Criteria for HIV Infection:

Children aged 18 months to <13 years are categorized as HIV infected for surveillance purposes if at least one of laboratory criteria or the other criterion is met.

Criteria for AIDS:

Children aged 18 months to <13 years are categorized for surveillance purposes as having AIDS if the criteria for HIV infection are met and at least one of the AIDS-defining conditions has been documented

see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5710a1.htm

children under 18 months age

Criteria for Definitive or Presumptive HIV Infection:

A child aged <18 months is categorized for surveillance purposes as definitively or presumptively HIV infected if born to an HIV-infected mother and if the laboratory criterion or at least one of the other criteria is met.

see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5710a1.htm

AIDS-defining conditions

The following is from the CDC (2008)2):

% Only among children aged <13 years. (CDC. 1994 Revised classification system for human immunodeficiency virus infection in children less than 13 years of age. MMWR 1994;43[No. RR-12].)

† Condition that might be diagnosed presumptively.

§ Only among adults and adolescents aged >13 years. (CDC. 1993 Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR 1992;41[No. RR-17].)

aids.txt · Last modified: 2013/03/17 17:06 (external edit)