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Carlo Torti

Publications and source records attributed to Carlo Torti.

At least 19 recordsLinked to original sources
PubMed2006

Influence of viral chronic hepatitis co-infection on plasma drug concentrations and liver transaminase elevations upon therapy switch in HIV-positive patients.

It is still controversial whether viral hepatitis co-infection can influence antiretroviral plasma drug concentrations and whether drug concentrations are correlated with liver enzyme elevations during highly active antiretroviral therapy. An analysis of data from a cohort of 220 human immunodeficiency virus (HIV)-infected patients was conducted. Univariate and multivariate logistic analyses were performed to identify predictors of plasma drug concentrations. The association of transaminase elevation with higher plasma drug concentrations was explored following stratification of patients into HIV monoinfected and hepatitis C virus (HCV) and/or hepatitis B virus (HBV) co-infected groups. Hepatitis co-infections were independently correlated with drug concentrations above the therapeutic cut-offs at Week 1 (P=0.06), Week 4 (P=0.04) and Week 12 (P=0.005). The apparent effect was independent of the possible impact exerted by other variables such as demographics and medication adherence. The incidence of relevant hypertransaminasaemia was low. Patients with hepatitis co-infections had higher rates of transaminase elevation than monoinfected HIV patients; however, risk of transaminase elevation was not associated with drug concentrations. The presence of HCV and/or HBV co-infections correlated with higher plasma drug concentrations, although it did not appear to influence hepatotoxicity risk.

Adult↗
PubMed2006

Comparison of a rule-based algorithm with a phenotype-based algorithm for the interpretation of HIV genotypes in guiding salvage regimens in HIV-infected patients by a randomized clinical trial: the mutations and salvage study.

BACKGROUND: There is still considerable uncertainty as to the best algorithm for interpreting human immunodeficiency virus (HIV) genotyping results. METHODS: A total of 318 subjects with HIV RNA levels of >1000 copies/mL were enrolled in 41 centers throughout Italy from 2001 through 2003, stratified on the basis of their drug history, randomized (1:1) to 2 arms to have their treatments modified on the basis of the results of HIV genotyping (as interpreted by virtual phenotype analysis or with use of a rule-based interpretation system), and followed up for 48 weeks. At least 1 nucleoside reverse-transcriptase inhibitor and 1 protease inhibitor had to be included in any new regimen; nonnucleoside reverse-transcriptase inhibitor-naive patients were also prescribed a nonnucleoside reverse-transcriptase inhibitor. Only drugs licensed in Italy were allowed. The primary end point was a decrease in HIV RNA level to <400 copies/mL by week 12 according to on-treatment analysis. RESULTS: The mean (+/- standard deviation) values at baseline were as follows: HIV RNA level, 4.1+/-0.74 log(10) copies/mL; CD4(+) T lymphocyte count, 410+/-262 cells/microL; reverse-transcriptase mutations, 4.8+/-2.9; and protease mutations, 2.8+/-2.5. There were 133 patients (41.8%) who were nonnucleoside reverse-transcriptase inhibitor naive and protease inhibitor experienced, 63 patients (19.8%) who were nonnucleoside reverse-transcriptase inhibitor experienced and protease inhibitor naive, and 122 patients (38.4%) who were 3-class experienced. A total of 192 patients completed 12 weeks of the treatment regimen assigned at baseline; at 12 weeks, 66.3% of patients in the virtual phenotype arm and 71.3% of patients in the rule-based interpretation arm had HIV RNA levels of <400 copies/mL (P = .46). No statistically significant difference between arms was observed by intention-to-treat analysis. CONCLUSION: Both the virtual phenotype and rule-based interpretation methods of HIV genotyping can guide the selection of effective antiretroviral drugs for a salvage regimen.

Adult↗
PubMed2006

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 micromol/l in females; >15 micromol/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.

Adult↗
PubMed2006

Influence of genotype 3 hepatitis C coinfection on liver enzyme elevation in HIV-1-positive patients after commencement of a new highly active antiretroviral regimen: results from the EPOKA-MASTER Cohort.

BACKGROUND: The independent role of hepatitis C virus (HCV) genotype 3 in liver transaminase elevation following highly active antiretroviral regimens is still controversial. METHODS: Analysis of data from a cohort of 492 HIV/HCV-coinfected patients was conducted using an intention-to-treat approach. Incidence of grade > or = III liver transaminase elevation was estimated per 100 patient-years of follow-up. Univariate and multiple proportional hazards regression analysis of factors that may predict liver enzyme elevation was performed. RESULTS: The incidence of grade > or = III hepatotoxicity was 25 per 100 patient-years among patients coinfected with HCV genotype 3 and 11 per 100 patient-years among those with other genotypes. On multiple proportional hazard regression analysis, time-to-grade > or = III liver enzyme elevation was directly correlated with HCV genotype 3 (hazards ratio [HR]: 2.0, 95% CI: 1.3 to 2.9; P = 0.001), male gender (HR: 2.7; 95% CI: 1.3 to 5.7; P = 0.007), chronic hepatitis B virus infection (HR: 2.9, 95% CI: 1.5 to 5.9; P = 0.002), and alanine aminotransferase level at baseline (per 10 IU/L HR: 1.10; 95% CI: 1.06 to 1.15; P < 0.001). In the same model, higher CD4 T-cell counts at baseline were inversely correlated with risk of hepatotoxicity (HR: 0.998; 95% CI: 0.997 to 0.999; P = 0.036). Moreover, among patients experienced to antiretroviral drugs, previous grade > or = III hepatotoxicity (HR: 2.8; 95% CI: 1.8 to 4.3; P < 0.001) was an adjunctive independent risk factor. CONCLUSIONS: HIV-positive patients coinfected with HCV genotype 3 displayed a higher risk of relevant hepatotoxicity, independently from other clinical variables. The impact of HCV genotype outweighed the role of drugs in determining hepatotoxicity.

Adult↗
PubMed2006

Influence of hepatitis C genotypes on lipid levels in HIV-positive patients during highly active antiretroviral therapy.

BACKGROUND: The independent role of HCV genotype 3 (HCV-3) in dyslipidaemia following highly active antiretroviral therapy (HAART) is still unexplored. METHODS: Analysis of data from a cohort of 307 HIV/HCV-coinfected patients and 415 HIV-monoinfected controls was conducted. Patients with available lipid levels at baseline and minimum 3-month follow-up were ranked into three groups by HCV status (HCV-3, other HCV genotypes or HCV negative). Univariate and multivariate GEE models were performed to assess factors correlated with lipid serum levels as coefficient (Coef., defined as mean difference [mg/dl] across the follow-up). Univariate and multivariate logistic regression analyses were performed for prediction of relevant hypertriglyceridaemia (> or = 500 mg/dl) and relevant hypercholesterolaemia (> or = 240mg/dl) at 3 months of follow-up. RESULTS: HCV-3 correlated with lower triglyceridaemia (Coef.=-38.22; P=0.001), independently from the other considered variables, including age, gender and use of stavudine or lopinavir. Even though HCV infection per se appeared to be protective, HCV-3 in particular was also independently associated with lower cholesterolaemia (Coef.=-46.35; P<0.001). At logistic regression analyses, HCV-3, but not HCV-non-3, was associated with lower risk of relevant hypercholesterolaemia (odds ratio [OR] 0.06; P=0.01) and relevant hypertriglyceridaemia (OR 0.11; P=0.05), independently from other considered variables. CONCLUSIONS: Our data confirm that HCV coinfection per se is associated with lower risk of hypercholesterolaemia after HAART. This effect was particularly attributed to HCV-3, which was the only genotype associated with lower triglyceridaemia during HAART.

Adult↗
PubMed2005

Natural history of chronic hepatitis B in co-infected patients.

HIV co-infection influences the course and natural history of hepatitis B virus (HBV) infection by impairing the quantity and quality of the innate and adaptive immune response. The rates of spontaneous resolution after acute infection and spontaneous anti-HBe and anti-HBs seroconversions are decreased, and levels of HBV replication are increased in HIV-infected patients. A more rapid progression of liver fibrosis and a higher rate of cirrhosis decompensation (but not hepatocellular carcinoma) have been demonstrated in co-infected patients. The risk of HBV-associated end-stage liver disease and liver-related mortality may be increased by HIV co-infection. Antiretroviral therapy may trigger spontaneous anti-HBe and anti-HBs seroconversion and/or a better immune control of HBV replication by restoring adaptive immunity, but can also increase hepatitis flares. Reactivation of chronic hepatitis B has been observed after suspension of anti-retrovirals with anti-HBV activity or after occurrence of HBV resistance to lamivudine. Future research should focus on: the impact of HIV-induced changes in innate and adaptive immune response and modifications induced by anti-retroviral therapy that may impact on progression of advanced chronic hepatitis B; the association between HBV genotype and clinical course of disease; and the role of occult HBV infection as a co-factor with other causes of liver injury.

Disease Progression↗
PubMed2005

Prediction of early and confirmed virological response by genotypic inhibitory quotients for lopinavir in patients naïve for lopinavir with limited exposure to previous protease inhibitors.

OBJECTIVE: To determine the impact of genotypic inhibitory quotient (GIQ) for lopinavir (LPV) in patients failing HAART with limited antiretroviral exposure. DESIGN: Retrospective analysis of a prospective trial. METHODS: Lopinavir GIQ was calculated as the ratio between the mean trough concentration (C(trough)) and the number of protease mutations using eight different HIV drug resistance mutation lists or algorithms. Early (by week 12) and confirmed (up to week 24) virological response (HIV-RNA< 400 copies/mL, ECVR) was used as dependent variable in logistic regression model. RESULTS: Seventy-one of 109 (65%) patients achieved ECVR. At multivariable logistic regression analysis, each mug/mL increase of GIQ was correlated with increasing probability of ECVR as far as the following mutations were computed: multi-protease inhibitor (PI) associated mutations listed by IAS (OR=1.17; 95% CI=0.99-1.39; P=0.058), mutations associated with LPV resistance by ANRS algorithm (OR=1.21; 95% CI=1.02-1.44; P=0.03), major mutations associated with LPV resistance by Stanford database (OR=1.16; 95% CI=1-1.35; P=0.05), and the whole set of mutations associated with LPV resistance in the same database (OR=1.22; 95% CI=1.02-1.46; P=0.03). Using ROC curve method, a specific threshold GIQ was assessed, above which this parameter could predict ECVR with the highest sensitivity (74.6% with GIQ obtained through Stanford LPV mutations) or specificity (89.5% with GIQ obtained through ANRS LPV mutations). CONCLUSIONS: Our results suggest that increasing GIQ can improve virological outcome even in patients with limited exposure to PIs. Further studies are necessary to understand what HIV protease mutations should be considered and whether such mutations should be weighted differently to improve LPV GIQ predictive value.

Adult↗
PubMed2005

Incidence and risk factors for liver enzyme elevation during highly active antiretroviral therapy in HIV-HCV co-infected patients: results from the Italian EPOKA-MASTER Cohort.

BACKGROUND: The risk of hepatotoxicity associated with different highly active antiretroviral therapy (HAART) regimens (containing multiple-protease inhibitors, single-protease inhibitors or non nucleoside reverse transcriptase inhibitors) in HIV-HCV co-infected patients has not been fully assessed. METHODS: Retrospective analysis of a prospective cohort of 1,038 HIV-HCV co-infected patients who commenced a new HAART in the Italian MASTER database. Patients were stratified into naïve and experienced to antiretroviral therapy before starting the study regimens. Time to grade > or =III hepatotoxicity (as by ACTG classification) was the primary outcome. Secondary outcome was time to grade IV hepatotoxicity. RESULTS: Incidence of grade > or =III hepatotoxicity was 17.71 per 100 patient-years (p-yr) of follow up in naïve patient group and 8.22 per 100 p-yrs in experienced group (grade IV: 4.13 per 100 p-yrs and 1.08 per 100 p-yrs, respectively). In the latter group, the only independent factors associated with shorter time to the event at proportional hazards regression model were: previous liver transaminase elevations to grade > or =III, higher baseline alanine amino-transferase values, and use of a non nucleoside reverse transcriptase inhibitor based regimen. In the naive group, baseline aspartate transaminase level was associated with the primary outcome. CONCLUSION: Use of a single or multiple protease inhibitor based regimen was not associated with risk of hepatotoxicity in either naïve or experienced patient groups to a statistically significant extent. A cautious approach with strict monitoring should be applied in HIV-HCV co-infected experienced patients with previous liver transaminase elevations, higher baseline alanine amino-transferase values and who receive regimens containing non nucleoside reverse transcriptase inhibitors.

Adult↗
PubMed2005

Exploratory analysis for the evaluation of lopinavir/ritonavir-versus efavirenz-based HAART regimens in antiretroviral-naive HIV-positive patients: results from the Italian MASTER Cohort.

OBJECTIVE: This retrospective longitudinal cohort study compared the virological and immunological responses to highly active antiretroviral therapy containing either efavirenz or lopinavir/ritonavir in previously antiretroviral-naive HIV-infected patients. PATIENTS AND METHODS: A total of 472 patients were selected (348 efavirenz and 124 lopinavir/ritonavir). The primary endpoint of this study was virological success (HIV RNA <50 copies/mL). The immunological response was assessed on the basis of either CD4+ T cell count variations (absolute and percentage) with respect to baseline values or categorical endpoints (defined as either a CD4+ T cell increase of > or =1;50 cells/mm(3) at week 24 or of > or =1;75 cells/mm(3) at week 48). RESULTS: At intention-to-treat (ITT) analysis, the adjusted odds ratio of virological success for patients who started lopinavir/ritonavir, compared with those who started efavirenz, was 0.54 (95% CI: 0.33-0.89, P = 0.016) at week 24 and 0.40 (95% CI: 0.33-0.89, P = 0.002) at week 48. However, patients receiving lopinavir/ritonavir had a more pronounced CD4+ T cell recovery, demonstrating both a mean absolute and percentage increase up to week 48 (MANOVA P < 0.0001). CONCLUSIONS: Although comparisons of drug efficacy in non-randomized studies should be viewed with caution, from a virological point of view efavirenz-containing regimens performed as well (on-treatment analysis) or better (ITT analysis) than those containing lopinavir/ritonavir. In contrast, immunological outcome appeared to favour lopinavir/ritonavir.

Adult↗
PubMed2005

A randomized controlled trial to evaluate antiretroviral salvage therapy guided by rules-based or phenotype-driven HIV-1 genotypic drug-resistance interpretation with or without concentration-controlled intervention: the Resistance and Dosage Adapted Regimens (RADAR) study.

BACKGROUND: It is not well defined whether concentration-controlled intervention (CCI) and rules-based human immunodeficiency virus (HIV) type 1 genotype drug-resistance interpretation (GI) or virtual phenotype drug-resistance interpretation (VPI) may improve the outcome of HIV salvage therapy. METHODS: In a prospective, randomized, controlled trial, patients were randomized (on a factorial basis) to change treatment after either GI or VPI, and they then were further randomized to the control arm (no CCI) or the CCI arm. Protease inhibitor (PI) and nonnucleoside reverse-transcriptase inhibitor (NNRTI) trough concentration (Ctrough) values were determined at weeks 1, 4, 12, and 24 of the study. RESULTS: Among 230 patients, virological benefit (defined by an HIV RNA load of <400 copies/mL at week 24) was not statistically different, either between patients in the GI and VPI arms or between patients in the CCI and control arms. A virological benefit was found for patients in the CCI arm, compared with patients in the control arm, but this benefit was not statistically significant (56.8% vs. 64.3% at week 4 and 63.6% vs. 74% at week 12). Dosage adaptation was possible for only a fraction of patients, because of low rates of treatment adherence or patient refusal to increase dosages. In the logistic regression analysis, independent predictors of virological response at week 24 were a PI Ctrough value and/or an NNRTI Ctrough value in the higher quartiles (or above cutoff levels) and a low number of PIs previously received. Moreover, receipt of a regimen that contained PIs boosted with ritonavir was an independent predictor of virological response. CONCLUSIONS: The present study did not support the routine use of CCI for patients undergoing salvage treatment, probably as a result of existing difficulties associated with its clinical application. However, a higher Ctrough value appeared to be correlated with treatment response. No major differences were found between VPI or GI when they are used together with expert advice for the selection of salvage treatment combinations.

Adult↗
PubMed2005

Early virological failure after tenofovir + didanosine + efavirenz combination in HIV-positive patients upon starting antiretroviral therapy.

A prospective, randomized pilot trial was conducted in naive patients comparing three different combinations: zidovudine+lamivudine+lopinavir/ritonavir (arm A) versus tenofovir+lamivudine+efavirenz (arm B) versus tenofovir+didanosine+efavirenz (arm C). HIV-RNA slope (days 1, 3, 7, 14 and 28) was slower in arm C with respect to arm B (P < 0.0001). Seven out of eight patients (87.5%) reached undetectable HIV-RNA by week 28 in arm A, 10/10 (100%) in arm B and 6/10 (60%) in arm C. Among arm C patients who failed at week 4, one HIV isolate showed 67N and 219Q, and another one showed 210F and 215D substitutions in the HIV reverse transcriptase gene at baseline, respectively. Non-nucleoside reverse transcriptase inhibitor resistance-related mutations appeared first, followed by 65R mutations in all cases. Efavirenz AUC(0-24) values were lower in arm C with respect to arm B, especially in patients who failed early. A high virological failure rate after tenofovir+didanosine+efavirenz correlated with a slower HIV-RNA decrease and a peculiar accumulation of resistance mutations. A constellation of factors could be correlated with early failure events in patients receiving this combination such as resistance mutations or polymorphisms present at baseline, low CD4+ T-cell count or advanced disease and unexpectedly low efavirenz plasma levels.

Adult↗
PubMed2004

Selection of antiretroviral therapy guided by genotypic or phenotypic resistance testing: an open-label, randomized, multicenter study (PhenGen).

The phenotype/genotype (PhenGen) open-label, randomized, multicenter study evaluated the genotype/virtual phenotype (vPt) and real phenotype (rPt) for choosing a new highly active antiretroviral therapy regimen at failure. Patients with a plasma viral load (pVL) between 2000 and 200,000 copies/mL and a CD4 cell count >200/microL, failing > or =2 regimens (<6 drugs), were randomized for vPt or rPt. Three hundred three patients were enrolled: 111 and 108 patients received a new treatment in the vPt and rPt arms, respectively. The 2 groups were comparable for baseline patient characteristics and treatment history. The new therapy was in agreement with expert advice in 58.5% of cases. After 6 months, no statistical differences were found in the mean absolute change from baseline CD4 cells (+55 and +46 cells/muL; P = 0.7), mean pVL log decrease (-1.35 and -1.37; P = 0.8), or proportion of patients with a pVL <400 copies/mL (54.8% in vPt arm and 52.6% in rPt arm; P = 0.9). At multivariate analysis, variables independently associated with failure of the new regimen were: pVL at baseline (odds ratio [OR] = 1.81; P < 0.021), number of nucleoside reverse transcriptase inhibitor-associated mutations (OR = 1.21; P = 0.001), number of protease mutations (OR = 1.15; P < 0.001), and recycling of indinavir (OR = 4.63; P = 0.019). Patients' adherence to the prescribed regimen (OR = 0.23; P < 0.001), number of active drugs in the new regimen (OR = 0.55; P = 0.001), and adherence to expert advice (OR = 0.37; P < 0.001) predicted virologic response. The vPt is as predictive of treatment outcome as the rPT. Use of expert advice significantly improved the response to therapy.

Adult↗
PubMed2004

[The novel non-A, non-E hepatitis viruses and their pathogenic effect].

Molecular techniques have allowed the identification of new viruses in a number of patients with cryptogenic hepatitis. Whether they are clinically inapparent or true hepatitis agents remains unknown for some of them. Latest described viruses include GBV, TTV and SENV. However, based on the limited data available, they do not seem to be contenders for the new hepatitis virus title. However, researchers are looking for a role of these viruses in other chronic and acute human diseases. Only a careful evaluation of the data and the scientific concordance of all the evidence will resolve the question of whether they are only commensal viruses or pose a real pathogenic potential.

Circoviridae↗
PubMed2004

Drug resistance mutations and newly recognized treatment-related substitutions in the HIV-1 protease gene: prevalence and associations with drug exposure and real or virtual phenotypic resistance to protease inhibitors in two clinical cohorts of antiretroviral experienced patients.

This study aimed at identifying HIV-1 protease amino acid changes associated with protease inhibitor (PI) exposure and susceptibility. New amino acid substitutions were correlated with the number of experienced PIs, reaching statistical significance only for those at positions 3, 44, and 74. The correspondence multivariate model demonstrated that > or =3 experienced PIs and substitutions or mutations at positions 3, 46, 54, 73, 74, and 84 were correlated with PI cross-resistance, including resistance for lopinavir and amprenavir in this cohort of patients who were naive for these drugs.

Amino Acid Substitution↗