Neopterin to Predict Disease Progression in Intravenous Drug Users Infected with HIV-1

Abstract

Most of our knowledge about the natural history of HIV infection comes from cohorts of homosexual men and men with hemophilia. The natural history of Human Immunodeficiency Virus (HIV) infection in intravenous drug users (IVDUs) is different from other people at risk in as far as some diseases, such as bacterial pneumonia or endocarditis, contribute to morbidity and mortality (Moss 1989); however, these diseases related to drug intake are not listed in the existing HIV staging classifications nor in the AIDS definition. A staging system for HIV infection should be easily capable of determining individual prognosis for all people at risk, but such a system is still lacking (Chaisson 1990). Therefore, the identification of factors correlated with and possibly contributing to the outcome of infection with HIV is important for our understanding of the pathogenesis and natural history of HIV infection and in designing therapeutic trials. Many reports address the possibility of early prediction of HIV-1 related disease progression. Low numbers of CD4+ T cells and low ratios of CD4+/CD8+ T cells were shown to be associated with a more unfavourable disease course (Polk 1987, Moss 1988, Eyster 1989, Fahey 1990, Fernandez-Cruz 1990). Additionally, HIV-1 p 24 antigenaemia (de Wolf 1988), increased concentrations of ß2-microglobulin in serum (Moss 1988, Anderson 1990) and increased urinary and/or serum concentrations of neopterin (Fahey 1990, Fuchs 1988, Fuchs 1989) indicated more rapid progression of the disease. However, the question remains whether these data, which were raised mainly from cohorts of homosexual men and men with haemophilia, also are valid for people with intravenous drug use. The aim of our study was to investigate the power of urinary neopterin to predict the development of AIDS or Walter Reed stage 5 (oral candidiasis in combination with a CD4 T cell count below 400 × 10⁻⁶/liter).