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HIV AIDS classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ammu Susheela, M.D. [2]

Overview

Overview

Many definitions have been developed for epidemiological surveillance of HIV/AIDS such as the Bangui definition and the 1994 Expanded World Health Organization AIDS Case Definition. However, these systems are neither sensitive nor specific for clinical staging. In developing countries, the World Health Organization staging system for HIV infection and disease that uses clinical and laboratory data is widely employed. The Centers for Disease Control (CDC) Classification System for HIV/AIDS is another primary system used that is primarily based on CD4 T-lymphocyte counts.

Classification

Classification

WHO Staging System for HIV Infection and Disease in Adults and Adolescents[1]

Clinical stage Features
Clinical stage 1
Clinical stage 2
Clinical stage 3

Conditions where a presumptive diagnosis can be made on the basis of clinical signs or simple investigations

Conditions where confirmatory diagnostic testing is necessary

Clinical stage 4

Conditions where a presumptive diagnosis can be made on the basis of clinical signs or simple investigations

Conditions where confirmatory diagnostic testing is necessary

WHO Staging System for HIV Infection and Disease in Children (Revised 2006) [1]

Clinical stage Features
Clinical stage 1
Clinical stage 2
Clinical stage 3

Conditions where a presumptive diagnosis can be made on the basis of clinical signs or simple investigations

Conditions where confirmatory diagnostic testing is necessary

Clinical stage 4

Conditions where a presumptive diagnosis can be made on the basis of clinical signs or simple investigations

Conditions where confirmatory diagnostic testing is necessary

CDC Classification System

CDC Classification System

The table below shows the HIV infection stage, based on age-specific CD4+ T-lymphocyte count or CD4+ T-lymphocyte percentage of total lymphocytes. [2]

Stage* Age on date of CD4 T-lymphocyte test
<1 year 1—5 years 6 years through adult
Cells/µL % Cells/µL % Cells/µL %
1 ≥1,500 ≥34 ≥1,000 ≥30 ≥500 ≥26
2 750—1,499 26—33 500—999 22—29 200—499 14—25
3 <750 <26 <500 <22 <200 <14
*The stage is based primarily on the CD4+ T-lymphocyte count; the CD4+ T-lymphocyte count takes precedence over the CD4 T-lymphocyte percentage, and the percentage is considered only if the count is missing.
References

References

  1. 1.0 1.1 WHO case definitions of HIV for surveillance and revised clinical staging and immunological classification of HIV-related disease in adults and children. 2006.
  2. “CDC HIV/AIDS Surveillance Publications”.

Template:WH Template:WS

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