Objective: To assess the value of concentrations of soluble receptors for tumour necrosis factor (sTNFR) as markers for disease progression in HIV infection.Design: We measured concentrations of sTNFR in the serum of 32 HIV-infected male patients in various stages of disease and in 12 healthy male control subjects. Correlations between the levels of sTNFR and CD4+ lymphocyte counts were calculated.Results: Serum levels of sTNFR p55 and p75 were elevated in parallel with severity of clinical stage. sTNFR p55 levels were higher at later stages of HIV infection (Centers for Disease Control stage IV) with or without concurrent illness, whereas sTNFR p75 was already elevated in asymptomatic carriers, compared with controls. There was an inverse correlation between sTNFR concentrations and CD4+ lymphocyte counts.Conclusions: Our results suggest that sTNFR concentrations could be potential markers for disease progression in HIV infection.