Maria A. Sambeat

Subcutaneous adipocyte apoptosis in Hiv-1 protease inhibitor-associated lipodystrophy

BACKGROUND Inhibitors of HIV-1 protease produce a rapid decrease in plasma HIV-1 RNA, with concomitant immune reconstitution. However, severe metabolic side effects together with a previously unseen form of lipodystrophy have been associated with long-term use of protease-inhibitor therapy. The pathogenic mechanisms underlying HIV-1 protease inhibitor-associated lipodystrophy are still largely unknown. METHODS Fourteen HIV-infected patients with HIV-1 protease inhibitor-associated lipodystrophy had a biopsy of subcutaneous fat performed in the antero-lateral aspect of the right leg. The samples were submitted for standard pathologic study together with a careful search for adipocyte apoptosis. Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP-digoxigenin nick end labelling (TUNEL) method, using the ApopTag kit (Oncor, Gaithersburg, Maryland, USA). The procedure was performed between three and five times for each sample. Appropriate positive and negative controls were used. Controls which were subcutaneous fat biopsies from patients with untreated melanoma were also examined for the presence of apoptosis. RESULTS Fourteen HIV-infected patients with a mean exposure to HIV-1 protease inhibitors of 12.6 +/- 3.7 months (range: 6-21 months), developed the characteristic features of HIV-1 protease inhibitor-associated lipodystrophy. All but one patient had an abnormal waist:hip ratio, and they all exhibited an abnormal serum lipid profile. Pathologically, subcutaneous fat atrophy was a constant feature, along with focal lipogranuloma formation and vascular proliferation. One of the eleven assessable biopsy samples was negative for the presence of apoptosis, six showed focally positive apoptotic cells, and the remaining four biopsies demonstrated moderate positivity. Apoptotic changes were also detected in endothelial cells. Apoptotic changes were more pronounced in patients with higher increases in CD4 and CD8 counts, and in those with a greater decay in plasma viral load. CONCLUSIONS Subcutaneous adipocyte apoptosis occurs in lipoatrophic areas of patients with HIV-1 protease inhibitor-associated lipodystrophy.

Paradoxical CD4+ T-cell decline in HIV-infected patients with complete virus suppression taking tenofovir and didanosine.

Background: Tenofovir (TDF) and didanosine (ddI) are both adenosine analogues with convenient posology, strong potency and a relatively high genetic barrier for resistance. The popularity of this combination, however, has been questioned due to concerns about pharmacokinetic interactions and increased risk of pancreatitis and hyperglycemia. Less information is available about other possible side effects. Patients and methods: HIV-infected individuals who initiated a protease inhibitor-sparing regimen between September 2002 and June 2003 at five hospitals, and had at least one subsequent visit within the next 12 months, always with complete virus suppression, were retrospectively assessed. Only drug-naive individuals and patients who simplified a prior successful antiretroviral regimen were analysed. Results: Outcomes were analysed in 570 individuals according to treatment modality (98 drug-naive versus 472 simplified); the nucleoside analogue (NA) backbone (298 with TDF + ddI, 88 with ddI, 44 with TDF, and 140 with neither ddI nor TDF); and the third agent used (378 with non-nucleoside analogues versus 192 with NA). Significant CD4+ T-cell declines were seen in patients taking ddI + TDF with respect to all other NA combinations, including ddI or TDF separately. Patients exposed to high ddI doses or taking a third NA showed more pronounced CD4 declines. Plasma levels of ddI correlated with the extent of CD4+ T-cell loss. Conclusion: Patients receiving ddI + TDF-based combinations show CD4+ T-cell declines despite achieving complete virus suppression. This effect generally progresses with time. An imbalance in adenosine metabolites within CD4+ T lymphocytes may explain this phenomenon, which resembles the genetic purine nucleoside phosphorylase deficiency syndrome.

Switching to Nevirapine Decreases Insulin Levels but Does Not Improve Subcutaneous Adipocyte Apoptosis in Patients with Highly Active Antiretroviral Therapy–Associated Lipodystrophy

Subcutaneous adipocyte apoptosis occurs in lipotrophic areas of patients with highly active antiretroviral therapy (HAART)-associated lipodystrophy. Fourteen patients with HAART-associated lipodystrophy had 2 subcutaneous biopsies for evidence of adipocyte apoptosis, the second after a randomized change to nevirapine (n=8) or after remaining on a regimen of indinavir-based HAART (n=6). Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP-digoxigenin nick end-labeling method. Patients who were switched to nevirapine had a significant decrease in insulinemia and a significant increase in the glucose:insulin ratio. Overall, subcutaneous adipocyte apoptosis increased in 3 patients who were switched to nevirapine and in 3 who continued to receive indinavir but decreased in 2 patients switched to nevirapine and another 2 who continued to receive indinavir. Subcutaneous adipocyte apoptosis continues to occur in lipotrophic areas of patients with HAART-associated lipodystrophy despite switching from indinavir to nevirapine, suggesting that such a strategy will be useless for reversal of lipoatrophy.

A randomized study comparing triple versus double antiretroviral therapy or no treatment in HIV-1-infected patients in very early stage disease: the Spanish Earth-1 study.

BACKGROUND Most current guidelines state that antiretroviral therapy should be considered for HIV-infected patients with plasma HIV RNA > 5000-10000 copies/ml and CD4 cells > 500 x 10(6) cells/l. However, there is increasing concern about whether this is the optimal point to begin treatment or whether it is better to delay the initiation to more advanced stages. OBJECTIVE To study the immunological and virological benefits of starting antiretroviral therapy at these early stages. METHODS A total of 161 HIV-infected asymptomatic patients with CD4 cell count > 500 x 10(6) cells/l and viral load > 10000 copies/ml were randomly assigned to one of five treatment groups: no treatment, twice daily zidovudine and thrice daily zalcitabine (ZDV-ddC), twice daily zidovudine and didanosine (ZDV-ddI), twice daily stavudine and didanosine (D4T-ddI), or a twice daily three-drug regimen with stavudine and lamivudine and ritonavir. The endpoints were progression to < 350 x 10(6) cells/l CD4 cells, to < 500 x 10(6) cells/l with either two Centers for Disease Control class B symptoms or an increase of viral load > 0.5 log10 copies/ml above baseline, or to AIDS or death. In various substudies, the lymphoid tissue and cerebrospinal fluid viral load, development of genotypic resistance, proliferative responses to mitogens and cytomegalovirus, and HIV-1 specific antigens and other immunophenotypic markers were also analysed. RESULTS Progression rates to study endpoints within 1 year were greater in the control group (31%) than in all groups receiving antiretroviral therapy pooled together (5%; estimated hazard ratio 7.41; 95% confidence interval 5.72-74.55; P < 0.001). The peak mean viral load decrease was greater in the three-drug group when compared with any of the three groups with a two-drug regimen (2.32, 1.65, 1.72 and 1.84, respectively; P < or = 0.001). At 1 year, viral load remained below 20 copies/ml in 30 out of 33 patients in the three-drug group (91%) and in only eight out of 94 patients (9%) in two-drug groups (P = 0.001). The peak mean increase in CD4 cells was also greater in the three-drug group than in the double treatment arms (259 versus 85, 144 and 145 x 10(6) cells/l, respectively; P = 0.001). By comparison, 36% of patients in the three-drug group regimen had to change the therapy as a result of adverse events. Substudies were performed in 60 patients recruited at two sites. Tonsillar tissue HIV RNA was measured in seven patients (two in the two-drug groups and five in the three-drug group) in whom plasma HIV RNA was < 20 copies/ml at 1 year. It was 15151 and 133333 copies/mg tissue in the two patients from the two-drug group, < 40 copies/mg tissue in four patients in the three-drug group, and 485 copies/mg in one patient in the three-drug group. At 1 year there was a mean increase of 4.21+/-2.94% in CD8+CD38+ cells in the control group and a decrease of 9.48+/-3.36% in the two-drug groups (P = 0.01), and 19.87+/-3.64 in the three-drug group (P = 0.001 and P = 0.05, for comparisons with control group and two-drug groups, respectively). Although proliferative responses to cytomegalovirus antigens were significantly greater in those receiving antiretroviral therapy, response to HIV-1 p24 antigen was not detected in any patient in either treatment group. CONCLUSIONS This study supports the recommendation to start antiretroviral therapy with a three-drug combination during very early stages of HIV-1 disease, at least if viral load is above a cut-off point (10000 copies/ml in our study). The risk of progression was sevenfold higher in non-treated patients at 8 months of follow-up. Some immune system parameters improved toward normal values after 1 year of antiretroviral therapy, but the proliferative response of CD4 T lymphocytes against the p24 HIV-1 antigen was not recovered. Therapeutic approaches with more potent, better-tolerated and more convenient regimens will increasingly favour early intervention with antiretroviral t

Comparison of twice-daily stavudine plus once- or twice-daily didanosine and nevirapine in early stages of HIV infection: the Scan Study.

ObjectivesTo evaluate the safety and effectiveness of once-daily didanosine and nevirapine plus twice-daily stavudine versus twice-daily administration of all three drugs. MethodsThis open-label, randomized, multicentre study enrolled 94 antiretroviral-naive patients with chronic HIV infection, CD4+ cell counts > 500 × 106 cells/l, and viral loads > 5000 copies/ml. Patients were treated with either 40 mg stavudine (twice daily) plus 400 mg didanosine (once daily) and 400 mg nevirapine (once daily) or 40 mg stavudine (twice daily) plus 200 mg didanosine (twice daily) and 200 mg nevirapine (twice daily). ResultsAfter 12 months, 68% of patients who received twice-daily didanosine and nevirapine had viral loads < 200 copies/ml in the intention-to-treat and 79% in the on-treatment analysis, respectively. The corresponding values for patients treated with didanosine and nevirapine, taken once-daily, were 73 and 85%. The percentages of patients in each group with viral loads < 5 copies/ml at 12 months were 40% (once daily ) and 45% (twice daily) for the intention-to-treat analysis. Five of 11 patients (45%) with plasma viral loads < 5 copies/ml at 12 months had detectable virus in tonsillar tissue. Genotypic resistance to nevirapine was noted in seven of the 14 patients with detectable viral load at month 12. Mean changes in CD4+ cell counts for patients treated with stavudine plus once- or twice-daily didanosine and nevirapine were 154 and 132 × 106 cells/l, respectively. Treatment was interrupted due to adverse events in seven patients (8%) (four who received once-daily didanosine and nevirapine and three treated with twice-daily doses). ConclusionsThe combination of twice-daily stavudine plus once-daily didanosine and nevirapine was as safe and well tolerated as twice-daily administration of all three agents. Both regimens were equally effective in reducing viral loads and in increasing CD4+ cell counts.

Epidemiological characteristics and predictors of late presentation of HIV infection in Barcelona (Spain) during the period 2001-2009

BackgroundEarly diagnosis of HIV infection can prevent morbidity and mortality as well as reduce HIV transmission. The aim of the present study was to assess prevalence, describe trends and identify factors associated with late presentation of HIV infection in Barcelona (Spain) during the period 2001-09.MethodsDemographic and epidemiological characteristics of cases reported to the Barcelona HIV surveillance system were analysed. Late presentation was defined for individuals with a CD4 count below 350 cells/ml upon HIV diagnosis or diagnosis of AIDS within 3 months of HIV diagnosis. Multivariate logistic regression were used to identify predictors of late presentation.ResultsOf the 2,938 newly diagnosed HIV-infected individuals, 2,507 (85,3%) had either a CD4 cell count or an AIDS diagnosis available. A total of 1,139 (55.6%) of the 2,507 studied cases over these nine years were late presenters varying from 48% among men who have sex with men to 70% among heterosexual men. The proportion of late presentation was 62.7% in 2001-2003, 51.9% in 2004-2005, 52.6% in 2006-2007 and 52.1% in 2008-2009. A decrease over time only was observed between 2001-2003 and 2004-2005 (p = 0.001) but remained constant thereafter (p = 0.9). Independent risk factors for late presentation were older age at diagnosis (p < 0.0001), use of injected drugs by men (p < 0.0001), being a heterosexual men (p < 0.0001), and being born in South America (p < 0.0001) or sub-Saharan Africa (p = 0.002).ConclusionLate presentation of HIV is still too frequent in all transmission groups in spite of a strong commitment with HIV prevention in our city. It is necessary to develop interventions that increase HIV testing and facilitate earlier entry into HIV care.

Tumour necrosis factor alpha in fat redistribution syndromes associated with combination antiretroviral therapy in HIV-1-infected patients: potential role in subcutaneous adipocyte apoptosis.

Background  The pathogenesis of fat redistribution syndromes (FRS) observed in the setting of highly active antiretroviral therapy (HAART) for the treatment of HIV‐1‐infection remains elusive. A dysregulation of the tumour necrosis factor alpha (TNF‐α) system occurs in HIV‐infected patients with FRS.

Relevance of HIV-1-specific CD4+ helper T-cell responses during structured treatment interruptions in patients with CD4+ T-cell nadir above 400/mm3

Objectives: To analyze the dynamics of both HIV-1-specific CD4+ and CD8+ T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. Methods: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-γrelease from CD8+ T cells were measured over a minimum study period of 2 years. Results: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4+ LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8+ T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8+ T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). Conclusions: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.

Gynecomastia among HIV-Infected Patients Is Associated with Hypogonadism: A Case-Control Study

BACKGROUND The prevalence, risk factors, and potential hormonal abnormalities associated with gynecomastia in a cohort of HIV-infected men are poorly understood. METHODS Breast enlargement was assessed in consecutively evaluated HIV-infected men, and gynecomastia was subsequently confirmed with sonography. For each patient with breast enlargement, a randomly selected control subject without breast enlargement was studied. Clinical data were obtained, including age, body mass index, clinically evident lipodystrophy, prior symptomatic hyperlactatemia, current antiretroviral therapy and duration of exposure to each antiretroviral drug, history of injection drug use, and serological status regarding hepatitis B and hepatitis C. Laboratory parameters, including plasma HIV-1 RNA load, CD4 cell count, free testosterone index, and levels of fasting triglycerides, cholesterol, prolactin, total testosterone, sex hormone-binding globulin, 17-beta-estradiol, follicle-stimulating hormone, luteinizing hormone, and thyroid-stimulating hormone, were measured. RESULTS There were 44 of 2275 patients with breast enlargement, of whom 40 (1.8%) had gynecomastia. The mean free testosterone index (+/-SD) was significantly lower among the 40 patients with gynecomastia (42.6%+/-24.0%) than among the 44 control subjects (58.0%+/-25.3%) (P=.006). Although the proportion of patients who were receiving treatment with zidovudine, stavudine, and/or efavirenz at the time of the present study was significantly different between case patients and control subjects, the duration of exposure to each individual antiretroviral drug was not. Lipoatrophy (adjusted odds ratio [OR], 5.6; 95% confidence interval [CI], 1.7-18.6; P=.005), hepatitis C (adjusted OR, 6.1; 95% CI, 1.8-20.6; P=.003), and hypogonadism (adjusted OR, 7.6; 95% CI, 1.8-32.2; P=.003) were independent factors associated with gynecomastia. CONCLUSIONS The data suggest that gynecomastia among HIV-infected patients is related to hypogonadism, rather than to an adverse effect of antiretroviral drugs.

Polymorphism of RANTES chemokine gene promoter is not associated with long-term nonprogressive HIV-1 infection of more than 16 years

To examine whether polymorphisms of the RANTES chemokine gene promoter are associated with long-term nonprogressive HIV-1 infection in white Spanish subjects, we performed a cross-sectional genetic association case-control study. Two-hundred sixty-seven white Spaniards were studied: 58 were HIV-1-infected long-term nonprogressors (LTNPs) of more than 16 years, 109 were HIV-1-infected usual progressors (UPs), and 100 were control subjects. Three RANTES single nucleotide polymorphisms (SNPs) at positions −28C>G, −109T>C, and −403G>A were assessed. The prevalence of the CCR5Δ 32 allele was also examined. Genotyping was performed using polymerase chain reaction and automatic sequencing analysis methods. Genotype and allele frequencies between the 3 groups were compared by the χ2 test and the Fisher exact test. The distribution of allelic variants of RANTES in controls, UPs, and LTNPs, respectively, was 3%, 2%, and 5% for −28G; 4%, 2%, and 2% for −109C; and 18%, 18%, and 18% for −403A (P = not significant). The differences were still nonsignificant when we exclusively analyzed individuals not carrying the CCR5Δ32 allele. We conclude that LTNP of more than 16 years is not associated with SNPs in the RANTES gene promoter in white Spanish HIV-1-infected subjects.