Evaluation of the World Health Organization staging system for HIV infection and disease in Ethiopia: association between clinical stages and laboratory markers

Objective: To study the association between the clinical axis of the, World Health Organization (WHO) staging system of HIV infection and disease and laboratory markers in HIV-infected Ethiopians. Design: Cross-sectional study. Methods: Clinical manifestations and stage of HIV-positive individuals part icipating in a cohort study of HIV infection progression, and of HIV-positi ve: patients hospitalized with suspicion of AIDS, were compared to CD4+ T-c ell count-and viral load. Results: Of the 86 HIV-positive participants of the cohort study, 53 (62%). 16 (19%), 16 (19%), and one (1.2%) were in stage 1, 2, 3 and 4, respective ly. Minor weight loss (n = 15) and pulmonary tuberculosis (n = 9) were the most commonly diagnosed conditions among the 38 (44%) symptomatic HIV-posit ive individuals. Although 23 (27%) HIV-positive participants had CD4+ T-cel l-counts:less than 200 x 10(6)/l, only one was in clinical stage 4. Among 7 9 hospitalized HIV-positive patients, 15 (19%) and 64 (81%) were in stage 3 and 4, respectively. The majority (83.5%) had CD4+ T-cell counts < 200 x 1 0(6)/l. Individuals at stage 3 had lower CD4+ T-cell counts and higher vira l loads when seen in hospital as compared to cohort participants (P = 0.06 and 0.008, respectively). When grouping the two study populations, the medi an CD4+ T-cell count decreased (337, 262, 225, 126, and 78 x 10(6)/l, p < 0 .01), and the median viral load increased (4.08, 3.84, 4.47, 5.65, and 5.65 log(10) copies/ml, P < 0.01), with increasing clinical stage of HIV infect ion (1, 2, 3 cohort, 3 hospital, and 4, respectively). Median CD4+ T-cell c ounts were remarkably low in HIV-negative participants (749 x 10(6)/l), and in HIV-positive participants at stage 1 and 2 (337 and 262 x 10(6)/l, resp ectively). Conclusions: There was a good correlation between WHO clinical stages and b iological markers. CD4+ T-cell counts were low in Ethiopians, particularly during early stages of HIV-1 infection, and preliminary reference values at different stages of HIV-1 infection were determined. In HIV-infected Ethio pians, lymphocyte counts less than 1,000 x 10(6)/l in non-hospitalized indi viduals, and less than 2,000 x 10(6)/l in hospitalized patients, had high p ositive predictive value, but low sensitivity, in identifying subjects with low CD4+ T-cell counts (<200 x 10(6)/l) who would benefit from chemoprophy laxis of opportunistic infections. The on-going longitudinal study will be useful to confirm the prognostic value of the WHO staging system. (C) 1999 Lippincott Williams & Wilkins.