The Walter Reed staging classification for HTLV-III/LAV infection.

Patients with acquired immunodeficiency syndrome (AIDS) represent a minority of those who have been infected with human T-lymphotropic virus type III (HTLV-III). The clinical presentation of patients with HTLV-III infections can range from asymptomatic through chronic generalized lymphadenopathy, to subclinical and clinical T-cell deficiency. The US Army has recently adopted a staging classification for HTLV-III infection. The purpose of the Walter Reed (WR) staging Classification is to provide uniformity for routine clinical evaluation of military personnel with HTLV-III infection, to facilitate understanding of the natural history of these infections, and to help evaluate the clinical response to antiviral treatment regimens. Stage WR0 designates high-risk contacts, while stages WR1-6 require documentation of HTLV-III infection. Stages WR1-6 show ascending degrees of disease, so that those classified in WR6 manifest antibodies to HTLV-III, chronic lymphadenopathy, T helper cell counts below the normal limit, delayed hypersensitivity, thrush, and opportunistic infection. HTLV-III infections with symptoms are designated by the addition of the letter B, while the occurrence of Kaposi's sarcoma is designated by adding the letter K. This classification scheme is based on the fact that the T helper cell is the principal target cell of HTLV-III and the clinical observation that the functional integrity of the T helper cell determines the clinical presentation. Preliminary studies in 39 sequential patients followed for over 18 months found that patients who entered in stages WR3-WR6 had a slow but progressive course to the next stage or death. Many questions about clinical progression remain, but it is hoped that this staging classification will facilitate their resolution.