Giuliana Cologni

Ultrasensitive assessment of residual low-level HIV viremia in HAART-treated patients and risk of virological failure.

Background:Low-level viremia (LLV) is measurable, with enhanced assays, in many subjects with HIV RNA levels <50 copies per milliliter. The clinical consequences of LLV are unknown. Methods:In a prospective study in HIV-1–infected adults, HIV RNA levels were determined with an ultrasensitive test (3 copies/mL) based on a real time polymerase chain reaction. The primary end point was to evaluate LLV prediction of virological failure, defined as a confirmed plasma HIV RNA level >50 copies per milliliter. Results:One thousand two hundred fourteen patients were followed for (mean) 378 days. At baseline, 71.5% were <3 copies per milliliter below the limit of detection (BLD). The risk of failing highly active antiretroviral therapy in the following 4 months for patients BLD was 0.4% compared with a 3.2% risk for those with LLV (P < 0.0001; odds ratio: 7.52). There was a significant (P < 0.0001) linear relationship between the HIV RNA and the risk of virologic failure. LLV receiver operating curve analysis showed an area under the curve of 0.76 (95% confidence interval: 0.68 to 0.84) that significantly (P < 0.0001) predicted the risk of failure. The risk of an unconfirmed viral blip was higher in patients with LLV (3.9%) than in those BLD (1.1%) (P < 0.0001; odds ratio: 3.56). Longer exposure to antiretrovirals, current use of nonnucleoside reverse transcriptase inhibitors, longer time BLD, and current HIV RNA <3 copies per milliliter were independent predictors of a positive outcome. Interpretation:Viral replication may be the cause of LLV, at least in some patients. A LLV >3 copies per milliliter is linked to a significant increment of risk of virological failure leading to drug resistance. Patients with measurable LLV should be managed to better evaluate, over time, the risk of failure and to limit its consequences.

Insulin resistance impairs rapid virologic response in HIV/hepatitis C virus coinfected patients on peginterferon-alfa-2a.

Objectives:To investigate the association between insulin resistance and rapid virologic response. Design:All consecutive HIV/hepatitis C virus coinfected patients who started peg-interferon alpha-2a (180 μg/week) and ribavirin 1000–1200 mg/day were analysed. Methods:Insulin resistance was defined according to the homeostasis model of assessment-insulin resistance calculated as fasting insulin (mIU/l) × fasting glucose (mmol/l)/22.5. Rapid virologic response was defined as testing negative for hepatitis C virus-RNA after 4 weeks of therapy. Fasting levels of insulin and glucose in plasma were measured in all patients on the first day of treatment. Hepatitis C virus-RNA was determined by quantitative PCR assay (version 3.0). Hepatitis C virus-RNA was measured by qualitative PCR assay (COBAS 2.0) after 4 weeks of treatment. Results:Seventy-four HIV/hepatitis C virus coinfected patients were enrolled [mean age 41.7 years (SD 5.3), 61 men, 54.1% with advanced fibrosis (F3-4 according to METAVIR classification), 52.4% with infection by hepatitis C virus genotype 1 or 4]. Rapid virologic response was reached by 30 subjects. In the multivariate analysis the independent predictors of rapid virologic response were: genotype 1 or 4 [adjusted odds ratio 0.18 (0.06–0.55)], hepatitis C virus-RNA < 400.000 UI/ml [adjusted odds ratio 0.229 (0.09–0.92)] and homeostasis model of assessment-insulin resistance more than 3.00 [adjusted odds ratio 0.1 (0.05–0.6)]. Conclusion:The homeostasis model of assessment-insulin resistance score should be evaluated and possibly corrected before starting anti-hepatitis C virus therapy.

Analysis of severe hepatic events associated with nevirapine-containing regimens: CD4+ T-cell count and gender in hepatitis C seropositive and seronegative patients.

AbstractBackground: Nevirapine-containing regimens have been associated with a risk of significant elevations of liver transaminase levels. Higher risk in antiretroviral-naive populations has been related to gender and CD4+ T-cell count (women with CD4+ T-cell counts of ≥250/mm3 or men with CD4+ T-cell counts of ≥400/mm3, i.e. group at risk). However, recent studies do not confirm this association in HIV populations comprising patients who are antiretroviral-experienced. Moreover, the predictive value of gender and CD4+ T-cell count on the risk of raised transaminase levels has been poorly investigated in populations of patients co-infected with hepatitis C virus (HCV). Methods: Analysis of HIV-positive patients receiving nevirapine-containing regimens for the first time was conducted. Grade ≥III hepatotoxicity (i.e. ≥5 × upper limit of normal in alanine aminotranferase or aspartate aminotransferase levels) was the primary endpoint. Univariate and multivariable Cox proportional hazard regression models were separately conducted among HCV-antibody (Ab)-positive and HCV-Ab-negative patients. Results: Amongst 905 patients, 49% were HCV-Ab-positive and 79% were antiretroviral-experienced. Grade ≥III liver transaminase elevations developed in 7.1% of patients, accounting for an incidence of 2.47 (95% CI 1.97, 3.09) per 100 patient-years of follow-up. HCV-Ab reactivity was associated with a 3-fold increase in risk of developing relevant liver transaminase elevations (95% CI 1.75, 5.3; p < 0.001), whereas gender and CD4+ T-cell count did not impact significantly. When analysis was performed in HCV-Ab-negative patients, the outcome was independently correlated with the group at risk (hazard ratio [HR] 3.66; 95% CI 1.20, 11.14; p = 0.022). By contrast, in HCV-Ab-positive patients, the group at risk was not significantly associated with the outcome. Conclusions: Most of the excess rates of relevant raised transaminase levels in patients prescribed nevirapine-containing regimens could be attributed to HCV co-infection. Gender and CD4+ T-cell count appeared to have a statistically significant impact on the risk of relevant transaminase level elevations in HCV-negative, but not in HCV-positive patients, probably due to a diluting effect of HCV. Incidence of hepatic events after nevirapine-containing regimens did not appear to be a major concern in our cohort of patients who were mainly antiretroviral-experienced and negative for HCV-Ab. Preferably, nevirapine should be avoided in HCV co-infected patients and in males with CD4+ T-cell counts of ≥400/mm3 or females with CD4+ T-cell counts of ≥250/mm3.

Updated Prevalence of Genotypic Resistance Among HIV-1 Positive Patients Naïve to Antiretroviral Therapy : A Single Center Analysis

Continuous surveillance of HIV primary resistance mutations is highly important due to their potential clinical impact. All patients naïve to antiretrovirals who had ≥1 genotypic resistance testing at the Institute of Infectious Diseases (Brescia, Northern Italy) between 2001 and 2006 were analyzed. Primary resistance mutations were defined using epidemiological and clinical criteria. Mutations were interpreted using the Stanford University Algorithm. Logistic regression analysis was used to assess possible predictors of primary resistance mutations. Among 569 patients, 11% presented ≥1 mutation. Prevalence of primary resistance mutations to nucleoside reverse‐transcriptase inhibitors (NRTI), non‐nucleoside reverse‐transcriptase inhibitors (NNRTI), and protease inhibitors (PI) was 6.3%, 6%, and 1.6%, respectively. The most frequent mutations to NRTI were substitutions at position 215 (215Y in 3 patients, and 215 revertants in 16), 41L (13), 219Q (12), and 210W (10). Among mutations to NNRTI, 103N was found in 21 patients, while 181C, 188L, and 190A/S in 8, 3, and 4 patients, respectively. Fifty‐one patients (9%) had high‐to‐intermediate resistance to ≥1 antiretroviral drug before starting the treatment. Regarding the new generation drugs, nine patients had intermediate resistance to etravirine, five patients had intermediate resistance to tipranavir, while five, one, and seven patients had low resistance to etravirine, tipranavir, and darunavir. Homosexuals were more likely to harbor a virus with primary resistance mutations (OR:2.68; 95% CI:1.44–5.00; P = 0.002) while non‐Italian nationality was protective (OR:0.38; 95% CI:0.17–0.86; P = 0.020). Prevalence of primary resistance mutations suggests that genotypic resistance testing should be performed before starting treatment in naïve patients in Italy, particularly when NNRTI are prescribed. J. Med. Virol. 80:747–753, 2008.

Influence of folate serum concentration on plasma homocysteine levels in HIV-positive patients exposed to protease inhibitors undergoing HAART.

Background: Homocysteinemia (Hcy) increase and risk factors in HIV-positive patients are not clear yet. Methods: HIV-positive patients on stable highly active antiretroviral therapy (HAART) regimens for at least 6 months were enrolled in this cross-sectional study. Among other factors, vitamin B12, folate and length of exposure to protease inhibitors (PIs) were evaluated for their possible correlation with hyper-Hcy (>13 µmol/l in females; >15 µmol/l in males) by logistic regression analysis. Results: Ninety-eight HIV-positive patients were recruited. Twenty-eight (28.6%) had hyper-Hcy. Length of exposure to antiretroviral therapy and PIs did not result to be significantly associated with hyper-Hcy risk. Normal folate level was the only factor associated with the outcome, resulting protective from hyper-Hcy, either at univariate (OR = 0.22; CI 95% = 0.06–0.86; p = 0.029) and multivariable (OR = 0.24; CI 95% = 0.06–0.94; p = 0.04) logistic regression analysis. Folate predictive value of hyper-Hcy risk was driven by levels in the lowest quartiles of the study population (i.e. <10.9 nmol/l). Conclusions: No significant correlations were observed between hyper-Hcy and length of exposure to antiretroviral therapy or PIs. Folate could be a confounding factor in the association between hyper-Hcy and PI exposure found by others. The potential value of folate supplementation, in those who are deficient and in those with hyper-Hcy, merits study.

Immune Correlates of Virological Response in HIV-Positive Patients after Highly Active Antiretroviral Therapy (HAART)

Correlates of immune reconstitution after highly active antiretroviral therapy (HAART) are not completely understood, in particular as far as viro-immunological discordant responses are concerned. HIV-positive patients on stable HAART for > or = 1 year were recruited. Viro-immunological responses were categorized according to positive or negative area under the curve (AUC) variations for HIV plasma viral load (pVL) and CD4+ T-cell counts measured at least every 4 months. The following parameters were evaluated: lymphocyte spontaneous apoptosis (LSA), intracellular Bcl-2 expression in both CD4-CD45RA+ and CD4-CD45R0+, IL-7 and IL-15 plasma concentrations, and lymphocyte TRECs levels. Sixty-one patients were enrolled. A significant inverse correlation was found between CD4+ T-cell count and pVL AUC (r = 0.45; p = 0.0003). Patients with pVL response had higher levels of Bcl-2 in CD4-CD45R0+ (mean 65,409 MESF vs. 54,018 MESF; p = 0.089) and higher IL-15 (mean 1.34 pg/mL vs. 1.05 pg/mL; p = 0.069, respectively). Higher LSA and lower TRECs levels were found in viro-immunological non-responder patients with respect to those who had viro-immunological response (mean 24.84% vs. 14.89%; p = 0.01, and mean 17,796 copies/10(6) cells vs. 29,251 copies/10(6) cells; p = 0.68, respectively). Virological suppression may allow Bcl-2 and IL-15 hyperexpression during incomplete immune-reconstitution phase, while more complete immune reconstitution appeared to be marked by both high TRECs and low LSA levels, possibly indicating both central and peripheral CD4+ T-cell repopulations at this stage.

Plasma HIV load and proviral DNA decreases after two standard antiretroviral regimens in HIV-positive patients naïve to antiretrovirals.

(i) To compare early decrease of HIV plasma viral load (pVL) after two standard combinations of highly active antiretroviral therapy (HAART). (ii) To evaluate variations of proviral HIV-DNA load on conditions of sustained pVL undetectability. Two different sub-studies of a multicentre prospective randomized controlled trial which compared two first-line HAART (i.e., zidovudine+lamivudine+lopinavir/ritonavir versus tenofovir+lamivudine+ efavirenz). Only patients enrolled at the coordinating centre (University of Brescia) were included in the two sub-studies. In the first sub-study, we calculated pVL decrease with respect to baseline at any of the following time-points: days 1, 3, 7, 14 and 28. Decreases of the pVL were compared between the two treatment groups. In the second sub-study, we analyzed variation of proviral HIV-DNA load in CD4+ T-cells from baseline to week 52 only in patients who maintained the same treatment regimen and had sustained undetectable pVL. In either studies, linear regression analysis was used to investigate what factors could influence variations of pVL and of proviral HIV-DNA load. (i) 64 patients were studied. A significant decrease of pVL was found from day 3 on, without statistically significant differences between the two study groups. However, after adjusting for possible confounders, tenofovir+lamivudine+efavirenz resulted to be associated with greater pVL decreases. (ii) 45 patients were studied. Mean proviral HIV-DNA load decreased from 1,610 (95%CI: 879-2,341) to 896 (95% CI 499-1,293) copies/10(6) cells (P=0.05). Linear regression analysis showed that the decrease of proviral DNA load during follow-up was independently and inversely correlated with age. Further studies are needed to compare pVL decay between antiretroviral regimens and assess whether proviral HIV-DNA load is a surrogate marker of treatment effectiveness.

Virological effectiveness and CD4+ T-cell increase over early and late courses in HIV infected patients on antiretroviral therapy: focus on HCV and anchor class received

BackgroundThe aim of this study was to explore the effects of HCV co-infection on virological effectiveness and on CD4+ T-cell recovery in patients with an early and sustained virological response after HAART.MethodsWe performed a longitudinal analysis of 3,262 patients from the MASTER cohort, who started HAART from 2000 to 2008. Patients were stratified into 6 groups by HCV status and type of anchor class. The early virological outcome was the achievement of HIV RNA <500 copies/ml 4–8 months after HAART initiation. Time to virological response was also evaluated by Kaplan-Meier analysis. The main outcome measure of early immunological response was the achievement of CD4+ T-cell increase by ≥100/mm3 from baseline to month 4–8 in virological responder patients. Late immunological outcome was absolute variation of CD4+ T-cell count with respect to baseline up to month 24. Multivariable analysis (ANCOVA) investigated predictors for this outcome.ResultsThe early virological response was higher in HCV Ab-negative than HCV Ab-positive patients prescribed PI/r (92.2% versus 88%; p = 0.01) or NNRTI (88.5% versus 84.7%; p = 0.06). HCV Ab-positive serostatus was a significant predictor of a delayed virological suppression independently from other variables, including types of anchor class. Reactivity for HCV antibodies was associated with a lower probability of obtaining ≥100/mm3 CD4+ increase within 8 months from HAART initiation in patients treated with PI/r (62.2% among HCV Ab-positive patients versus 70.9% among HCV Ab-negative patients; p = 0.003) and NNRTI (63.7% versus 74.7%; p < 0.001). Regarding late CD4+ increase, positive HCV Ab appeared to impair immune reconstitution in terms of absolute CD4+ T-cell count increase both in patients treated with PI/r (p = 0.013) and in those treated with NNRTI (p = 0.002). This was confirmed at a multivariable analysis up to 12 months of follow-up.ConclusionsIn this large cohort, HCV Ab reactivity was associated with an inferior virological outcome and an independent association between HCV Ab-positivity and smaller CD4+ increase was evident up to 12 months of follow-up. Although the difference in CD4+ T-cell count was modest, a stricter follow-up and optimization of HAART strategy appear to be important in HIV patients co-infected by HCV. Moreover, our data support anti-HCV treatment leading to HCV eradication as a means to facilitate the achievement of the viro-immunological goals of HAART.

Long-term CD4+ T-cell count evolution after switching from regimens including HIV nucleoside reverse transcriptase inhibitors (NRTI) plus protease inhibitors to regimens containing NRTI plus non-NRTI or only NRTI.

BackgroundData regarding CD4+ recovery after switching from protease inhibitor (PI)-based regimens to regimens not containing PI are scarce.MethodsSubjects with virological success on first-PI-regimens who switched to NNRTI therapy (NNRTI group) or to nucleoside reverse transcriptase (NRTI)-only (NRTI group) were studied. The effect of the switch on the ongoing CD4+ trend was assessed by two-phase linear regression (TPLR), allowing us to evaluate whether a change in the CD4+ trend (hinge) occurred and the time of its occurrence. Furthermore, we described the evolution of the frequencies in CD4-count classes across four relevant time-points (baseline, before and immediately after the switch, and last visit). Finally, we explored whether the CD4+ counts evolved differently in patients who switched to NNRTI or NRTI-only regimens by considering: the overall CD4+ trends, the time to CD4+≥ 500/mm3 after the switch, and the area-under-the-curve (AUC) of the CD4+ after the switch.ResultsEight hundred and ninety-six patients, followed for a median of 2,121 days, were included. At TPLR, hinges occurred in 581/844 (68.9%), but in only 40/581 (6.9%) within a time interval (180 days) compatible with a possible relationship to the switch; furthermore, in 19/40 cases, CD4+ counts appeared to decrease after the hinges. In comparison with the NNRTI group, the NRTI group showed CD4+ count greater at baseline (P = 0.0234) and before the switch (P ≤ 0.0001), superior CD4+ T-cell increases after HAART was started, lower probability of not achieving CD4+ ≥ 500/mm3 (P = 0.0024), and, finally, no significant differences in the CD4+ T-cell AUC after the switch after adjusting for possible confounders (propensity score and pre-switch AUC). Persistence at CD4+ < 200/mm3 was observed in 34/435 (7.5%) patients, and a decrease below this level was found in only 10/259 (3.9%) with baseline CD4+ ≥ 350/mm3.ConclusionsSwitching from first-line PI to NNRTI- or NRTI-based regimens did not seem to impair CD4+ trend over long-term follow-up. Although the greater CD4+ increases in patients who switched to the NRTI-only regimen was due to higher CD4+ counts before the switch, several statistical analyses consistently showed that switching to this regimen did not damage the ongoing immune-reconstitution. Lastly, the observation that CD4+ T-cell counts remained low or decreased in the long term despite virological success merits further investigation.

Dideoxynucleoside HIV reverse transcriptase inhibitors and drug-related hepatotoxicity: a case report

This report regards the case of a 43 year-old HIV-positive woman who developed an episode of serious transaminase elevation during stavudine-including antiretroviral therapy. Diagnostic assessment ruled out hepatitis virus co-infection, alcohol abuse besides other possible causes of liver damage. No signs of lactic acidosis were present. Liver biopsy showed portal inflammatory infiltrate, spotty necrosis, vacuoles of macro- and micro-vesicular steatosis, acidophil and foamy hepatocytes degeneration with organelles clumping, poorly formed Mallory bodies and neutrophil granulocytes attraction (satellitosis). A dramatic improvement in liver function tests occurred when stavudine was discontinued and a new antiretroviral regimen with different nucleoside reverse transcriptase inhibitors was used. The importance of considering hepatotoxicity as an adverse event of HAART including stavudine, even in absence of other signs of mitochondrial toxicity should therefore be underlined. Liver biopsy may provide further important information regarding patients with severe transaminase elevation, for a better understanding of the etiology of liver damage.