Viral dynamics during structured treatment interruptions of chronic human immunodeficiency virus type 1 infection

Although antiviral agents which block human immunodeficiency virus (HIV) replication can result in long-term suppression of viral loads to undetectable levels in plasma, long-term therapy fails to eradicate virus, which generally rebounds after a single treatment interruption. Multiple structured treatment interruptions (STIs) have been suggested as a possible strategy that may boost HIV-specific immune responses and control viral replication. We analyze viral dynamics during four consecutive STI cycles in 12 chronically infected patients with a history (>2 years) of viral suppression under highly active antiretroviral therapy. We fitted a simple model of viral rebound to the viral load data from each patient by using a novel statistical approach that allows us to overcome problems of estimating viral dynamics parameters when there are many viral load measurements below the limit of detection. There is an approximate halving of the average viral growth rate between the first and fourth STI cycles, yet the average time between treatment interruption and detection of viral loads in the plasma is approximately the same in the first and fourth interruptions. We hypothesize that reseeding of viral reservoirs during treatment interruptions can account for this discrepancy, although factors such as stochastic effects and the strength of HIV-specific immune responses may also affect the time to viral rebound. We also demonstrate spontaneous drops in viral load in later STIs, which reflect fluctuations in the rates of viral production and/or clearance that may be caused by a complex interaction between virus and target cells and/or immune responses

Phenotypic hypersusceptibility to multiple protease inhibitors and low replicative capacity in patients who are chronically infected with human immunodeficiency virus type 1

Increased susceptibility to the protease inhibitors saquinavir and amprenavir has been observed in human immunodeficiency virus type 1 (HIV-1) with specific mutations in protease (V82T and N88S). Increased susceptibility to ritonavir has also been described in some viruses from antiretroviral agent-naïve patients with primary HIV-1 infection in association with combinations of amino acid changes at polymorphic sites in the protease. Many of the viruses displaying increased susceptibility to protease inhibitors also had low replication capacity. In this retrospective study, we analyze the drug susceptibility phenotype and the replication capacity of virus isolates obtained at the peaks of viremia during five consecutive structured treatment interruptions in 12 chronically HIV-1-infected patients. Ten out of 12 patients had at least one sample with protease inhibitor hypersusceptibility (change ≤0.4-fold) to one or more protease inhibitor. Hypersusceptibility to different protease inhibitors was observed at variable frequency, ranging from 38% to amprenavir to 11% to nelfinavir. Pairwise comparisons between susceptibilities for the protease inhibitors showed a consistent correlation among all pairs. There was also a significant relationship between susceptibility to protease inhibitors and replication capacity in all patients. Replication capacity remained stable over the course of repetitive cycles of structured treatment interruptions. We could find no association between in vitro replication capacity and in vivo plasma viral load doubling time and CD4(+) and CD8(+) T-cell counts at each treatment interruption. Several mutations were associated with hypersusceptibility to each protease inhibitor in a univariate analysis. This study extends the association between hypersusceptibility to protease inhibitors and low replication capacity to virus isolated from chronically infected patients and highlights the complexity of determining the genetic basis of this phenomenon. The potential clinical relevance of protease inhibitor hypersusceptibility and low replication capacity to virologic response to protease inhibitor-based therapies deserves to be investigated further

Circumcision and penile human papillomavirus prevalence in human immunodeficiency virus-infected men: heterosexual and men who have sex with men

AbstractMale circumcision is associated with a lower risk of penile human papillomavirus (HPV) infection in human immunodeficiency virus (HIV) uninfected men. Few studies have evaluated the role of male circumcision in penile HPV infection in HIV-infected men. The aim of this cross-sectional study was to examine the association between male circumcision and the prevalence of penile HPV infection among HIV-infected men—both men who have sex with men (MSM) and heterosexual men. Samples from 706 consecutive men included in the CARH-MEN cohort (overall 24% circumcised: 26% of MSM, 18% of heterosexual men) were examined by Multiplex-PCR. In the overall group (all HIV-infected men included), the prevalence of any penile HPV infection was 22% in circumcised men and 27% in uncircumcised men (OR = 1.0, 95% CI 0.6–1.6, adjusted analysis). In the circumcised group the overall prevalence of HPV infection was 22% in MSM and 24% in the heterosexual men, whereas in the uncircumcised group the prevalence was 26% and 28%, respectively. The prevalence of high-risk HPV types tended to be lower in the circumcised MSM (14% vs 21%, OR = 0.6, 95% CI 0.3–1.1, p 0.088), but it was similar in the heterosexual men (18% in circumcised vs 20% in uncircumcised). These results suggest that male circumcision may be associated with a lower prevalence of oncogenic high-risk penile HPV infection in HIV-infected MSM

Brain functional abnormality in schizo-affective disorder: an fMRI study.

Background.Schizo-affective disorder has not been studied to any significant extent using functional imaging. The aim of this study was to examine patterns of brain activation and deactivation in patients meeting strict diagnostic criteria for the disorder. METHOD: Thirty-two patients meeting research diagnostic criteria (RDC) for schizo-affective disorder (16 schizomanic and 16 schizodepressive) and 32 matched healthy controls underwent functional magnetic resonance imaging (fMRI) during performance of the n-back task. Linear models were used to obtain maps of activations and deactivations in the groups. RESULTS: Controls showed activation in a network of frontal and other areas and also deactivation in the medial frontal cortex, the precuneus and the parietal cortex. Schizo-affective patients activated significantly less in prefrontal, parietal and temporal regions than the controls, and also showed failure of deactivation in the medial frontal cortex. When task performance was controlled for, the reduced activation in the dorsolateral prefrontal cortex (DLPFC) and the failure of deactivation of the medial frontal cortex remained significant. CONCLUSIONS: Schizo-affective disorder shows a similar pattern of reduced frontal activation to schizophrenia. The disorder is also characterized by failure of deactivation suggestive of default mode network dysfunction

Aging-associated symptoms in the physician-patient dialogue in a group of long-term diagnosed HIV-infected individuals

Background: The significant decrease in mortality has resulted in a large number of individuals aged over 50 living with HIV infection. Additionally, the coexistence of certain pathologies suggests premature aging. In this scenario, the presence of aging-associated symptoms in the physician-patient dialogue is yet to be explored. Methods: Cross-sectional observational study to evaluate the presence of aging-associated symptoms in the physician-patient dialogue and to explore the possible differences between genders in a sample of 100 HIV-1 infected subjects diagnosed at least 15 years ago. The survey assessed questions/comments made by the patient, questions/comments made by the physician and patients’ interest in obtaining more information than was provided. Number of patients and percentages were given and compared using the w2 or Fisher exact test (as appropriate). Results: Participants were 60 men and 40 women, diagnosed with HIV infection a median (IQ) of 18 (15.7–21) years ago, who had a nadir CD4 and CD4 cell count at the study entry of 172 (95–272) and 543 (403–677), respectively. Eighty percent of the subjects had VL <25 copies and 42% were HCV/HIV co-infected (31 subjects with low fibrosis stage). The infection route had been mainly intravenous drug use (37%) and MSM (32%). Men and women had similar demographic and clinical characteristics. Sixty-two percent of the participants acknowledged asking their physicians about aging-associated symptoms (58% men vs 66% women; p=0.50), 48% reported that their physicians had provided information without having been asked (48% men vs 55% women; p=0.51) and 75% confirmed that they would like to have more information about aging-associated symptoms (22% men vs 80% women; p<0.001). Conclusions: Around half of the men and women interviewed had discussed aging-associated symptoms with their physician. However, this seemed insufficient for four-fifths of the women, who would have liked to have obtained more information about aging

Monotherapy with boosted protease inhibitors as antiretroviral treatment simplification strategy in the clinical setting

Antiretroviral treatment simplification with darunavir/ritonavir or lopinavir/ritonavir monotherapy maintains sustained HIV viremia suppression in clinical trials. However, data about the efficacy of this strategy in routine clinical practice is still limited, and no direct comparison between darunavir/ritonavir and lopinavir/ritonavir has been performed to date. We retrospectively studied all HIV-1-infected subjects who initiated monotherapy with darunavir/ritonavir or lopinavir/ritonavir while having plasma VL<50 c/mL, and had at least 1 subsequent follow-up visit in our clinic. When two consecutive PI-monotherapy regimens were used, each regimen was considered separately. The primary endpoint was the percentage of patients who maintained virological suppression (HIV-1 VL <50 c/mL) through follow-up. Virological failure was defined as at least two consecutive HIV-1 VL >50 c/mL. We also evaluated other reasons for treatment discontinuation. Analyses were performed considering all regimens (full dataset analysis) either as “on treatment” or as “treatment switch equals failure”. Five hundred and seventy-three PI-monotherapy regimens corresponding to 520 subjects were included, 262 with darunavir/ritonavir and 311 with lopinavir/ritonavir. Medians (IQR) follow-up were 50 (26.3–107.6) and 85.6 (36.9–179.1) weeks for subjects on darunavir/ritonavir and lopinavir/ritonavir, respectively (p<0.001). Overall, 67 (11.7%) subjects experienced virological failure, 23 (8.7%) were on darunavir/ritonavir and 42 (13.5%) were on lopinavir/ritonavir (p=0.796). Two hundred and three (77.5%) patients on darunavir/ritonavir and 154 (49.5%) on lopinavir/ritonavir maintained virological suppression in the “treatment switch equals failure” (p=0.002). Other reasons for treatment discontinuation were gastrointestinal toxicity and dyslipidemia in 7.2% and 5.9% of cases, respectively. Gastrointestinal toxicities and dyslipidemia leading to treatment discontinuation were more frequent in patients on lopinavir/ritonavir (10.6% and 10.3%, respectively) than in patients on darunavir/ritonavir (3.1% and 0.8%, respectively). Monotherapy with darunavir/ritonavir or lopinavir/ritonavir as simplification strategy appears to be effective and safe in subjects with virological suppression in clinical practice. Virological efficacy seems to be similar between regimens. However, rates of discontinuation due to toxicities were higher in subjects on lopinavir/ritonavir than darunavir/ritonavir

Effect of the human immunodeficiency virus type 1 reverse transcriptase polymorphism Leu-214 on replication capacity and drug susceptibility

A negative association between polymorphism Leu-214 and type-1 thymidine analogue mutations (TAM1) and a positive association with a clinically favorable virological response to thymidine analogue-based combination antiretroviral therapy have been described. In this study, the impact of Leu-214 on replication capacity and resistance to zidovudine (ZDV) of viruses containing TAM1 or TAM2 was determined. Leu-214 decreased the growth rate of viruses bearing Tyr-215, as well as their resistance to ZDV. This observation was confirmed by structural and molecular modeling data, suggesting a regulatory role for Leu-214 in the emergence and phenotypic resistance of TAM1

O331 Patterns of viral suppression on cART as predictors of uncontrolled viremia after starting a new antiretroviral after 1 January 2003

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