Prognostic usefulness of the Walter Reed staging classification for HIV infection.

We evaluated the usefulness of both the Walter Reed (WR) staging classification and the component criteria used in the system in predicting progression to AIDS. The WR classification was applied to a cohort of 431 men who were seropositive for the human immunodeficiency virus on entry into a prospective study. The WR classification was of limited usefulness, as only 133 men (31%) could be assigned to a WR stage. Among men who could be WR classified, only individuals in WR stage 5 were found to have a significantly more rapid progression to AIDS. The seropositive cohort was also classified based on initial CD4 cell number. Low CD4 counts (less than 400 cells/mm3) were significantly associated with progression to AIDS, and grouping seropositive men by CD4 number alone provided as much prognostic information as the WR classification. Skin test anergy was also a significant predictor for progression to AIDS, but only in individuals with low CD4 counts.