Tuberculosis results in activation of T cells and macrophages that may harbor latent human immunodeficiency virus (HIV-1). Although such activation is beneficial to the host in terms of mycobacterial disease, it may be deleterious in terms of HIV-1. In Ugandan HIV-1-seropositive patients with pulmonary tuberculosis, antigen-induced blastogenesis and production of tumor necrosis factor-alpha (a cytokine that induces expression of HIV-1 in latently infected cells) were 3-10 times greater than in controls. The mean serum beta 2-microglobulin level was 5.22 mg/L in recently diagnosed patients, significantly greater than levels in HIV-negative patients with tuberculosis or asymptomatic HIV-1-seropositive subjects. beta 2-microglobulin was significantly lower in subjects who had completed at least 2 months of antituberculous therapy. These observations suggest that HIV-1-associated tuberculosis is accompanied by immune activation that may result in increased HIV expression and accelerated progression to AIDS.

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The ability of commercially available PCR-based assays to accurately detect or quantitate human immunodeficiency virus type 1 (HIV-1) DNA or RNA in individuals predominantly infected with HIV-1 subtypes A and D is not known. Therefore, peripheral leukocytes from 43 individuals in Kampala, Uganda, positive for HIV by the Western blot (immunoblot) assay were tested by using the Roche AMPLICOR HIV-1 assay for the detection of DNA gag sequences. Plasma from these same individuals was tested by using the Roche HIV-1 AMPLICOR MONITOR HIV-1 assay for the quantitation of HIV-1 RNA gag sequences. In addition, peripheral leukocytes were tested for HIV-1 DNA by using a lower annealing temperature or a different primer pair for the HIV-1 pol region. The proportions of individuals with detectable HIV-1 DNA and RNA gag sequences by the Roche assays were 74 and 90%, respectively. The proportions positive for HIV-1 DNA sequences by using a 50؇C annealing temperature or the pol primer pair were 71 and 98%, respectively. In summary, the standard Roche assay did not detect HIV-1 DNA sequences in a significant number of HIV-1-infected individuals in Uganda. However, use of a pol primer pair increased the sensitivity of the assay to 98%. The sensitivity of the Roche AMPLICOR MONITOR assay for the detection and quantitation of HIV-1 RNA sequences was significantly higher than that of the DNA-based assay, but the efficiency of the assay, and hence, the accuracy of the values obtained with RNA, is not known. Modifications to existing assays are needed to enhance the sensitivities and accuracies of these commercially available assays for use in developing countries where non-B HIV-1 subtypes predominate.

The objective of this study was to determine the use of immune-complex dissociated (ICD) p24 antigen detection for the diagnosis and prognosis of HIV-1 infection in Ugandan children. Plasma collected prospectively from children born to HIV-1 infected Ugandan women was stored and later analyzed for the presence of neutralizable HIV-1 p24 antigen using the Coulter ICD p24 antigen and neutralization kits. HIV-1 infection status, disease progression, and survival of the children were determined. Specimens from 311 children born to HIV-1 infected women, including 138 HIV-1 infected children, and 113 children born to negative women were tested. Sixty-nine (50%) infected children were p24 antigen positive at least once. For early HIV-1 diagnosis, the specificity and positive predictive value of the assay were consistently high (>95% and >83% respectively), but the sensitivity was low (6-53%), especially in the first months of life. The presence of p24 antigenemia in the first two years of life was associated with poor survival (20%) by 80 months of age compared with infected children without antigenemia (43%, P < 0.001). Early detection of p24 antigen (6 months, P < 0.001). The data suggest that ICD p24 antigen detection is not a sensitive method for the determination of infant HIV-1 status in our cohort of HIV-1 infected Ugandan children tested in the first two years of life. There was a strong correlation, however, between the presence and time of onset of p24 antigenemia and mortality among HIV-1 infected children.