Eilke B. Helm

Changing incidence of AIDS-defining illnesses in the era of antiretroviral combination therapy.

Objective:To determine the incidence of AIDS-defining opportunistic infections and malignancies over a 5-year period from 1992 to 1996. Study population:Subcohort of 1003 homosexual men with HIV infection and CD4 count less than 200 × 106cells/l from the Frankfurt AIDS Cohort Study. Methods:Data including the earliest date that a CD4 T-lymphocyte count < 200 × 106/l was reached and the dates of AIDS-defining events were compiled from medical records. Incidence analyses for AIDS-defining events and death during the subsequent 5 years (1992–1996) were performed using rates per 100 person-years of exposure. Results:During the observation period, the number of patients per year with CD4 T-lymphocyte counts < 200 × 106/l varied between 402 and 511. In 1992, 56.7% of patients experienced at least one AIDS-defining illness, and 20.7% in 1996. The annual number of AIDS-defining events per 100 patient-years of observation declined from 143.5 in 1992 to 38.3 in 1996, and the number of AIDS-related deaths fell from 25.7 to 12.9. Analysis of the number of events confirmed this trend for malignancies and single opportunistic infections, with the exception of mycobacterial diseases. Conclusions:The incidence of AIDS-defining events in patients with advanced HIV infection at Frankfurt University Hospital has declined by more than 70% from 1992 to 1996.

Demonstration of the Th1 to Th2 cytokine shift during the course of HIV-1 infection using cytoplasmic cytokine detection on single cell level by flow cytometry.

Objective:To characterize changes of Th1/Th2 cytokine production by peripheral blood mononuclear cells (PBMC) that occur during the course of HIV infection by cytoplasmic cytokine staining on single cell level. Design and methods:Mitogen-stimulated PBMC from 16 healthy donors, 18 HIV-1-infected individuals without AIDS and 14 patients with AIDS were stained intracellularly with fluorescein-labelled MAb against interleukin (IL)-2, IL-4, IL-10 and interferon (IFN)-γ. Additionally, co-staining of CD4+ T-cell, CD8+ T-cell, natural killer (NK) cell, B-cell and monocytic markers was performed. Fluorescence staining was analysed by three-colour flow-cytometry. Results:A reduced percentage of IL-2 and IFN-γ (Th1 type)-producing cells among CD4+ T cells from HIV-1-infected individuals could be demonstrated. There was a continuous decrease of IFN-γ-producing CD4+ T cells in the course of HIV infection and a dramatic reduction of IL-2-expressing cells among CD4+ T cells in patients with AIDS. In contrast to Th1 cytokines, the frequency of Th2 cytokine expressing cells among CD4+ T cells increased in HIV-infected individuals. The maximum frequency of IL-4-expressing cells among CD4+ T cells was seen in HIV-infected individuals without AIDS, whereas the rate of IL-10-producing cells was highest in patients with AIDS. In HIV-infected individuals no significant proportion of Th0 cells expressing both Th1 and Th2 cytokines was detectable. In CD8+ T cells the percentage of IL-2 was expressing cells decreased continuously accompanied by a strong increase of the frequency of IFN-γ-producing cells. Conclusion:The decreased percentage of cells expressing IL-2 and IFN-γ in conjunction with an increased proportion of IL-4- and IL-10-producing cells among the CD4+ T cells in HIV-1-infected individuals demonstrate a Th1 to Th2 cytokine shift in the course of HIV infection on a single cell level. There was no evidence of a Th1 to Th0 cytokine shift. In addition to the loss of CD4+ T cells in HIV infection, the qualitative changes of Th1/Th2 cytokine expression may serve as a marker for progressive failure of cell-mediated immunity.

Virological response to protease inhibitor therapy in an HIV clinic cohort.

OBJECTIVE New antiretroviral strategies aim to reduce plasma HIV RNA (viral load) to below the limits of detectability of assays with the objective of reducing viral replication in order to stop or reverse the pathogenic process and prevent development of drug resistance. First use of a protease inhibitor might offer the most realistic chance of achieving this aim. Our objective was to study the virological response to protease inhibitors in patients taking them for the first time. METHODS A total of 901 patients from a large outpatient clinic were followed a mean of 15 months from the time of starting a protease inhibitor until 1 May 1998. Viral load and CD4 cell count measurements were made on average every 34 days. RESULTS Overall there was a 79% [95% confidence interval (CI), 76-82] probability of the patients achieving a viral load < 500 copies/ml by 24 weeks after starting the protease inhibitor. In a multiple Cox regression model, those with lower initial viral load [relative hazard (RH), 0.72; P < 0.0001], higher CD4 cell count (RH, 1.07; P = 0.002), those starting other new drugs at same time as the protease inhibitor (RH, 1.46 for two versus none; P = 0.003), those who were antiretroviral-naive, and those using indinavir or nelfinavir were more likely to achieve such levels. In those 651 patients achieving viral load < 500 copies/ml within 24 weeks, there was an estimated 53% (95% CI, 51-55) probability of rebound of viral load to > 500 copies/ml by 52 weeks from the first undetectable value. Again, those who had started other new drugs at the same time as the protease inhibitor (RH, 0.57; P = 0.003 for starting two versus none) tended to experience a lower probability of viral load rebound, as did those with higher initial CD4 cell count (RH, 0.87 per 100 x 10(6)/l higher; P = 0.0007). Those who took saquinavir achieved less durable virological responses than those who took other protease inhibitors. CONCLUSIONS Starting protease inhibitor therapy with two other new antiretroviral drugs simultaneously with protease inhibitor therapy offers a better best chance of achieving sustained viral load < 500 copies/ml than starting fewer new drugs.

Ex Vivo Induction of Apoptosis in Lymphocytes Is Mediated by Oxidative Stress: Role for Lymphocyte Loss in HIV Infection

Programmed cell death (apoptosis) of T-lymphocytes observed in human immunodeficiency virus (HIV) infected individuals could be linked to oxidative stress. Therefore, we have investigated whether reactive oxygen species (ROS) induce apoptosis, which might contribute to the cell loss during progression of HIV-1 infection. ROS were generated in peripheral blood mononuclear cells (PBMC) obtained from HIV-1-positive patients and from healthy controls by stimulation with bacteria or by treatment with hypoxanthine/xanthine oxidase, which has been shown to generate ROS without direct involvement of cytokines. A dose-dependent inhibition of ROS formation correlated with the reduction of apoptosis induced by both bacterial and hypoxanthine/xanthine oxidase stimulation, suggesting that ROS generation was responsible for the induction of apoptosis. In addition, hydrogen peroxide (H2O2) rather than superoxide (O2.-) was observed to induce apoptosis. ROS-dependent apoptosis was shown to be independent of cytokines such as tumor necrosis factor-alpha (TNF-alpha). ROS-induced apoptosis was significantly enhanced in HIV-infected subjects even in the very early stages after infection. Moreover, ROS-mediated apoptosis was not restricted to a particular lymphocyte subset. In view of the diminished oxidative resistance of HIV-infected individuals, our results suggest that ROS-mediated apoptosis might contribute to the deletion of lymphocytes and to the pathogenesis of the disease.

Changing incidence and prognostic factors of survival in AIDS-related non-Hodgkin's lymphoma in the era of highly active antiretroviral therapy (HAART).

Non-Hodgkins lymphoma is an AIDS-defining disease. The impact of HAART on the epidemiology and prognosis is debated controversially. A retrospective analysis has been performed in order to determine the influence of HAART. We collected data of 214 cases of AIDS-related Lymphoma (ARL) treated at our centre from January 1984 until May 2003 and analysed them using the Kaplan-Meier-, log rank- and Cox proportional hazard-model. The incidence of ARL increased between 1991 and 1994 up to a peak of 14.83 per 1000 patient years. In the subsequent periods from 1995 onwards however, it decreased to 3.7 in 1000 patient years. The incidence of AIDS-related primary CNS lymphomas (PCNSL) took a comparable, yet more pronounced development. Using the univariate Kaplan-Meier analysis prolonged survival was significantly associated with the achievement of a complete remission as well as with a favourable virological response to HAART. No significant differences could be shown for the use of protease inhibitors as well as for virological response being achieved before the diagnosis of NHL. When using the Cox model, complete remission overrides viral response and thus remained the only independent prognostic factor. Classical prognostic factors (CD4 count, prior Kaposi Sarcoma, extranodal manifestation, staging and histological subtype of NHL) were no longer significant for HAART patients in the multivariate analysis. These results illustrate the requirement for new prospective studies in order to determine the best options and ideal timing of coadministering chemotherapy and the type of HAART. Furthermore this study demonstrates that HAART decreases the incidence of ARL, and that achievement of a complete remission in patients suffering from ARL is--according to the multivariate analysis--the single most important prognostically relevant factor with respect to the time of survival.

The impact of protease inhibitor-containing highly active antiretroviral therapy on progression of HIV disease and its relationship to CD4 and viral load

ObjectiveTo compare the rate of disease progression according to viral load and CD4 cell count in patients receiving or not receiving highly active antiretroviral therapy (HAART), defined as protease inhibitor-containing regimens. DesignAn observational study, with prospectively collected data. MethodsAll patients attending the HIV Outpatient clinic as of 1 January 1995 (n = 2083) were included. Follow-up was until the first AIDS-defining event or death. Associations between viral load or CD4 cell count and disease progression were assessed using a person–years approach. Event rates were compared using Poisson regression analysis; a multivariate model was used to assess the independent effects of CD4, viral load and treatment group on event rates and to consider interactions between these variables. ResultsThe event rates increased with lower CD4 cell count and higher viral load for both treatment groups and were generally lower in the HAART group. In a multivariate analysis, lower CD4 cell counts and higher viral loads remained significantly associated with disease progression, irrespective of treatment group. However, the event rate was significantly lower for the HAART group compared with the control group (relative rate 0.53, P < 0.001). ConclusionsHAART-treated patients with high viral loads and CD4 cell counts experienced reduced disease progression compared with individuals with the same CD4 cell count and viral load not receiving HAART. Consequently, the short-term prognosis associated with viral load levels and CD4 cell counts may differ in patients on HAART. Whether this effect will be observed with non-protease-inhibitor-containing HAART is not known at this time.

Changing Incidence and Survival in Patients with AIDS-Related Non-Hodgkin's Lymphomas in the Era of Highly Active Antiretroviral Therapy (HAART)

To determine role of highly active antiretroviral therapy (HAART) and additional factors in incidence and outcome of patients with AIDS-related non-Hodgkins lymphomas (NHL) we retrospectively analyzed 257 cases of AIDS-related NHL (24 low-grade, 168 high-grade B-cell, 6 high-grade T-cell, and 59 primary CNS lymphomas (PCNSL) among 2004 patients with HIV-infection treated at the University Hospital of Frankfurt, Germany from January 1983 to May 1999. Data were evaluated by univariate and multivariate analyses, using overall survival as end point. Patients received CHOP-like therapy as standard treatment. Until May 1999 incidence of all diagnosed cases of NHL was decreasing (1991–94: 14.2% versus 1995–5/99: 12.8%). Mainly, the incidence of low-grade NHL and PCNSL clearly decreased whereas the incidence of high-grade B-cell NHL increased compared to all diagnosed cases of NHL (1983–86: 53.3% versus 1995–5/99: 78.6%). One-year survival probability of all screened patients with AIDS related NHL was 54%, while 5-year survival rate remained 5%. We found age < 25 years, development of NHL in the years before 1990, IVDU, CD4 counts < 150/μ1, PCNSL as well as NHL as the AIDS index disease, to be highly significant independent predictors of poor survival, including increased hazard ratios. In the era of HAART incidence of NHL is decreasing, mainly the incidence of low-grade NHL and PCNSL. Overall survival of patients has been prolonged with HAART. This development is mainly due to improvement of antiretroviral therapy, rather than to any fundamental changes in the chemotherapeutic treatment of NHL. Therefore, new treatment approaches for AIDS-related NHL should focus on more efficient antiretroviral therapy in association with combination chemotherapy.

Prevalence of antibodies to human herpesviruses and hepatitis B virus in patients at different stages of human immunodeficiency virus (HIV) infection

SummaryThe results of antibody assays for viruses of the herpes group (HSV, EBV, VZV and CMV) and for hepatitis B virus (HBV) were retrospectively evaluated in 439 HIV-seropositive patients classified into different stages of HIV infection. The prevalence of specific IgG, IgM and IgA antibodies in these groups was compared with that of a control group of HIV-negative unselected hospital patients. Antibodies to herpes viruses and HBV were more prevalent amongst HIV-seropositives, especially LAS and AIDS patients than in controls. However, marked differences were found only with CMV-IgG and anti-HBc-IgG, both with a comparatively low prevalence in HIV-negative persons (64.5% and 23.2%). Significantly more seropositives were found among asymptomatic HIV carriers (83.3% and 50%) and still more in patients with full-blown AIDS (95.4% and 82.5%). The increased frequency of CMV and HBV antibodies, already seen in asymptomatic HIV patients reflects their higher risk for sexually transmitted infections. Moreover, IgA antibodies to CMV were detected in 25.4% of LAS and 37.3% of AIDS patients, respectively, but only in 7.6% of the controls. Elevated CMV-IgA titres were found exclusively in HIV-infected persons. The differences in the antibody patterns found in this cross-sectional study may reflect the progression of the HIV disease. However, prospective follow-up studies are required to assess the value of these markers as indicators of prognosis in HIV-infected subjects.ZusammenfassungBei 439 HIV-positiven Patienten verschiedener Krankheitsstadien wurden retrospektiv die Ergebnisse der Antikörpertests gegen Viren der Herpesgruppe (HSV, EBV, VZV und CMV) und gegen Hepatitis-B-Virus (HBV) ausgewertet. Die Prävalenz spezifischer IgG-, IgM- und IgA-Antikörper wurde zwischen den verschiedenen Stadien der HIV-Infektion und mit einem Kontrollkollektiv HIV-negativer Krankhenhauspatienten verglichen. Die Durchseuchung mit Herpesviren und Hepatitis B war insgesamt bei HIV-positiven und insbesondere LAS-und AIDS-Patienten höher als im Kontrollkollektiv. Die größten Unterschiede zeigten sich für das CMV-IgG und das anti-HBc-IgG, beide mit einer vergleichsweise niedrigen Prävalenz bei HIV-negativen Personen (64,5% bzw. 23,2%). Der Anteil CMV und HBV-Seropositiver war deutlich höher in der Gruppe der asymptomatischen HIV-Träger (83,3% bzw. 50%) und noch mehr bei Patienten mit dem Vollbild AIDS (95,4% bzw. 82,5%). Die höhere Prävalenz von CMV- und HBV-Antikörpern bei asymptomatischen HIV- positiven Patienten entspricht ihrem erhöhten Risiko für sexuell übertragene Infektionen. Ferner wurde CMV-IgA bei 25,4% und 37,3% der LAS- bzw. AIDS-Patienten gegenüber nur 7,6% im Kontrollkollektiv nachgewiesen. Hohe CMV-IgA-Titer wurden ausschließlich bei HIV-infizierten Patienten gefunden. Der Vergleich der in dieser Querschnittsstudie gefundenen Antikörperprofile scheint die Progression der HIV-Krankheit widerzuspiegeln. Allerdings sind prospektive Verlaufsuntersuchungen erforderlich um den Wert dieser Marker als Prognosefaktoren sicher zu beurteilen.

Kaposi's sarcoma in HIV infection: impact on opportunistic infections and survival.

Objective:To determine the effect of Kaposis sarcoma on survival of HIV-infected patients. Methods:Retrospective cohort study to compare the survival of 241 HIV-infected homosexual patients with Kaposis sarcoma (cases) with that of 241 HIV-infected homosexual patients without Kaposis sarcoma (control subjects) but with a similar level of immunosuppression (measured by the absolute CD4+ lymphocyte count). Results:Cases and control subjects were similar in age, occurrence of previous opportunistic infections, and the use of antiretroviral therapy. The mean CD4+ lymphocyte counts were similar for cases and control subjects (185 × 106 versus 184 × 106/l, respectively). Cases had a higher incidence of opportunistic infections (5.95 versus 3.88 infections, respectively, per 100 person-months of observation) and a greater number of infections typical of late-stage HIV infection. Cases had a shorter overall survival than did control subjects (P = 0.0025). Kaposis sarcoma was associated with an increased risk of death (odds ratio, 1.28), even when adjusting for age, previous opportunistic infection, baseline CD4+ lymphocyte count, and antiretroviral therapy. Conclusion:Kaposis sarcoma appears to accelerate the clinical course of HIV infection. Opportunistic infections develop earlier and more often in patients with the disease than in control subjects. Survival was significantly shorter in patients with Kaposis sarcoma.

Increase in Vδ1+γδ T cells in the peripheral blood and bone marrow as a selective feature of HIV‐1 but not other virus infections

Dysregulation of T‐cell receptor (TCR) αβ bearing lymphocytes and an increase in Vδ1+γδ T cells are typical features of HIV‐1 infection. However, the role of γδ T cells remains unclear. Therefore, peripheral blood mononuclear cells (PBMC) of 103 HIV‐1‐infected patients were investigated with respect to expression of Vδ1. These results were compared to the Vδ1 expression of bone marrow mononuclear cells (BMMC). In contrast to healthy controls, Vδ1+ cells dominated among both PBMC and BMMC in HIV‐1‐infected patients. Analysis of the coexpression of CD25, CD8, HLA‐DR and CD45RO revealed a high prevalence of Vδ1/CD45RO and Vδ1/HLA‐DR double‐positive PBMC only in HIV‐1‐infected patients but not in healthy donors. Furthermore, analysis of the γδ TCR repertoire in patients infected with hepatitis B virus, hepatitis C virus, herpes simplex virus (HSV)‐1 and HSV‐2 showed that the selective enhancement of Vδ1+ cells was restricted to HIV infection and not observed in other virus diseases. Our data provide further support for the involvement of γδ T cells in immunosuppression and progression of HIV infection.