Effects on immunological and virological outcome of patients using one protease inhibitor or one non-nucleoside reverse transcriptase inhibitor in a triple antiretroviral therapy: normal clinical practice versus clinical trial findings

Epidemiology and Prevalence of Oral Candidiasis in HIV Patients From Chad in the Post-HAART Era

Oral candidiasis remains a common problem in HIV-infected individuals, especially in sub-Saharan Africa. Here, we performed the first study in Chad on the prevalence of oral yeasts carriage and oral candidiasis in HIV-positive subjects from southern Chad and analyzed the influence of HAART, CD4⁺ T-cell numbers, and antimycotics in 589 patients. These patients were recruited from a specialized medical center for HIV patients in Sarh and from a rural medical health dispensary in the vicinity, including a total of 384 HIV-positive and 205 HIV-negative individuals. Yeasts obtained from oral specimen were identified by MALDI-TOF MS and their antifungal susceptibility profiles determined. The overall prevalence of yeast colonization and symptomatic oral candidiasis in HIV-infected patients was 25.1%. The prevalence of oral candidiasis was higher in untreated than in HAART-treated HIV-positive patients (16% vs. 2%; p < 0.01). Oral candidiasis was furthermore associated with high fungal burdens of Candida albicans and a CD4⁺ T-cell number <200/μl. A shift toward non-albicans Candida species was observed under nucleoside-based HAART therapy. Azole antifungal drug resistance was only observed for the intrinsically resistant species Candida krusei and Candida glabrata. Prevalence of oral candidiasis in the studied area was very low. The species distribution was similar to other countries around the world, with C. albicans being dominant. Candida dubliniensis was not isolated. Nucleoside-based HAART therapy significantly reduced oral colonization as well as occurrence of oral candidiasis caused by C. albicans and led to a species shift toward non-albicans species. Antifungal resistance was not yet a concern in Chad.

Oral manifestations, salivary flow rates and Candida species in Thai HIV-infected patients

Background

Effects of various Highly Active Antiretroviral Therapy (HAART) regimens on oral heath are unclear. Objectives: We aimed to evaluate effects of HAART on oral manifestations, salivary flow rates (SFR) and Candida species in HIV-infected patients who took mostly non-protease inhibitor-based HAART regimens.

Material and Methods

A cross-sectional study was performed on HIV-infected patients taking and never taken HAART who attended Thai Red Cross AIDS Research Centre (n = 48). Non-HIV subjects were recruited as control (n = 20). Oral conditions and salivary flow rates were evaluated using oral examination and measurement of unstimulated and stimulated saliva. In addition, Candida colonization counts (colony forming units; CFUs) and Candida species from the collected saliva were evaluated using CHROMagar.

Results

The most common oral manifestation in HIV-infected subjects taking HAART was hyperpigmentation. Unstimulated and stimulated SFR among the three groups were not statistically significant. Candida colonization was detected in 64%, 65% and 35% of HIV-infected subjects taking HAART, HAART-naïve, and non-HIV subjects, respectively. While 20% and 35% of HIV-infected subjects with and without HAART, respectively, had Candida CFUs higher than 500/ml, all non-HIV carriers had Candida CFUs lower than 500/ml. The most common Candida colonization species was C. albicans in HAART and non-HIV groups. Interestingly, HAART-naïve group was colonized more by non-albicans species.

Conclusions

HAART has minimal effects on oral health. While HAART may not prevent Candida colonization, it might lead to reduction of non-albicans species. Because maintaining low Candida counts is important, HAART administration and antifungal sensitivity test should be considered in HIV-infected patients. Key words:HIV, Candida, HAART, Oral manifestation, Salivary flow rates.

Efficacy of antiretroviral therapy in Africa: effect on immunological and virological outcome measures -- a meta-analysis

This study is a systematic literature review exploring the efficacy of antiretroviral therapy (ART) in Africa through a meta-analysis of immunological and virological outcome measures at baseline and six subsequent time points. A literature search was conducted through two databases and references of relevant papers searched. The inclusion criteria were papers with data from the African continent with predominantly an adult population, who were ART naïve and human immunodefieciency virus-1-positive, data on the CD4 count and/or percentage undetectable viral load (UDVL) at a subsequent time-point following ART initiation. The search identified 368 papers. Of these 320 were excluded by title and abstract, 48 papers were accessed with a further 19 papers then excluded. Twenty-nine papers from 12 countries were included in the meta-analysis. All papers showed evidences of Grade III or IV. The mean CD4 count (cells/mm(3)) at baseline was 141.0 and viral load was 5.2 log(10). The mean CD4 count was 243.8, 248.9, 277.1, 274.1, 298.4, 374 at 3, 6, 12, 18, 24 and >24 months, respectively. The mean percentage with UDVL was 73.3, 74.7, 66.9, 68.1, 64.6, 73.5 at 3, 6, 12, 18, 24 and >24 months, respectively. In conclusion, the meta-analysis provides evidence that ART increases the CD4 count from three months until three years, and the majority of subjects had an UDVL (<400 copies/mL) at each analysed time-point. Though the grade of evidence is low, this analysis suggests that ART can be provided successfully within the continent of Africa even with the limitations of a resource-poor setting.

HIV protease inhibitors impact on apoptosis

HIV protease inhibitors are the backbone of HIV therapy. In addition to blocking intracellular HIV protease and dramatically decreasing viral burden, the protease inhibitors also regulate apoptosis. A growing body of data has confirmed the immunomodulatory effects of HIV protease inhibitors which block CD4+ and CD8+ T cell death in models of HIV infection. The mechanism of this apoptosis inhibition is still under active investigation and supported by several proposed hypothesis for how they alter the fate of the cell. More recently, the anti-apoptotic effects of the HIV protease inhibitors has been extended to the non-HIV, non-immune cell, whereby protease inhibitors prevent apoptosis, and disease, in animal models of sepsis, hepatitis and stroke. Interestingly, when HIV protease inhibitors are used at supra-therapeutic concentrations, they exert pro-apoptotic effects. This has been demonstrated in a number of tumor models. Although it is unclear how HIV protease inhibitors can induce apoptosis at increased concentrations, future research will define the targets of the immunomodulation and reveal the full clinical potential of this intriguing class of drugs.

Antiretroviral regimens for patients with HIV who fail first-line antiretroviral therapy

BACKGROUND

Highly active antiretroviral therapy has reduced the morbidity and mortality of patients with HIV/AIDS. A common first-line ART regimen includes a non-nucleoside reverse transcriptase inhibitor (NNRTI) and two nucleoside reverse transcriptase inhibitors (NRTIs). If treatment failure occurs, a change to second-line therapy is necessary.

OBJECTIVES

This meta-analysis aimed to assess the optimum antiretroviral regimen for patients with HIV who fail first-line therapy (ART-naive) with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV.

SEARCH STRATEGY

Electronic databases and conference proceedings were searched with relevant search terms without limits to language.

SELECTION CRITERIA

Randomised controlled trials of HIV-infected adult patients administered second-line ART after virologic failure of a first-line regimen were included. The primary outcome measure included the proportion of patients achieving undetectable plasma HIV RNA concentration (viral load). Secondary outcome measures included change in mean CD4 cell count, clinical resolution of symptoms, rate of adverse events, rate of change in therapy for failure, rate of change in therapy for toxicity, and mortality.

DATA COLLECTION AND ANALYSIS

Two authors assessed each reference for inclusion and exclusion criteria established a priori. Data were abstracted independently using a standardised abstraction form.

MAIN RESULTS

Twenty-one records were identified in total, 6 of which were duplicates. None of the records met inclusion criteria.

AUTHORS' CONCLUSIONS

There is insufficient evidence to evaluate second-line therapies in patients with HIV who fail first-line treatment with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV. Current recommendations are based on available resources and results from individualised treatment decisions based on resistance testing and clinician choice.

Flying in the face of resistance: antiviral-independent benefit of HIV protease inhibitors on T-cell survival

Human immunodeficiency virus (HIV) infection results in excessive apoptosis of infected and uninfected cells, mediated by host and viral factors present in plasma. As HIV protease inhibitors (PIs) have intrinsic antiapoptotic properties, we questioned whether HIV PIs could block HIV-induced CD4+ T-cell death independent of their effects on HIV replication. We demonstrate that HIV PIs block the death of CD4+ T cells induced by HIV glycoprotein 120 (gp120), Vpr, and Tat, as well as host signals Fas ligand, tumor necrosis factor, and tumor necrosis factor-related apoptosis-inducing ligand. Using gp120/CXCR4 as a model, we show that the HIV PIs specifically block mitochondrial apoptosis signaling. Furthermore, HIV PIs inhibit CD4+ T-cell death induced by viruses with high-level resistance to PIs (P<0.01) and apoptosis induced by serum of HIV patients with known resistance to HIV PIs (P=0.01). Together, these results show that HIV PIs block CD4+ T-cell death and have a beneficial effect on CD4+ T-cell survival despite PI resistance.

HIV protease inhibitors modulate apoptosis signaling in vitro and in vivo

HIV protease inhibitors are an integral part of effective anti-HIV therapy. The drugs block HIV protease, prevent proper packaging of HIV virions, and decrease the HIV viral burden in the peripheral blood of infected individuals. In addition to direct anti-viral effects, the HIV protease inhibitors also modulate apoptosis. A growing body of work demonstrates the anti-apoptotic effects of HIV protease inhibitors on CD4+ and CD8+ T cells during HIV infection. The mechanism of this apoptosis inhibition is supported by several proposed hypotheses for how they alter the fate of the cell, including preventing adenine nucleotide translocator pore function, which consequently prevents loss of mitochondrial transmembrane potential. More recently, the anti-apoptotic effects of the HIV protease inhibitors have been tested in non-HIV, non-immune cell, whereby protease inhibitors prevent apoptosis, and disease in animal models of sepsis, hepatitis, pancreatitis and stroke. Interestingly, when HIV protease inhibitors are used at supra-therapeutic concentrations, they exert pro-apoptotic effects. This has been demonstrated in a number of tumor models. Although it is unclear how HIV protease inhibitors can induce apoptosis at increased concentrations, future research will define the targets of the immunomodulation and reveal the full clinical potential of this intriguing class of drugs.