Acute human immunodeficiency virus type 1 infection

Multi-faceted role of naturally occurring autoantibodies in fighting pathogens

Naturally occurring antibodies (NAbs) play a vital role in the first line of defense against bacterial and viral infections. Most studies in mice and man have attributed this role to NAbs of the IgM isotype. However, there is also a significant amount of data on the anti-infectious function of NAbs of the IgG isotype. Most of these observations are derived from studies using a privileged source of NAbs, the pooled human IgG for intravenous application, IVIG. In addition to its use as a replacement in humoral immunodeficiencies, IVIG is extensively used in autoimmune and inflammatory diseases. The properties of NAbs, the principal components of IVIG, are considered crucial for their immune-regulatory properties, owing to their ability to recognize self-antigens and even autoantibodies. By virtue of these specificities for several cellular antigens, including exposed proteins that act as receptors for a variety of pathogens, certain NAbs in IVIG have a therapeutic role in preventing or modulating infections. We summarize in this chapter several examples that highlight the importance of NAbs in the control of certain bacterial and viral infections.

Acute HIV infection: a misleading presentation

Detecting acute HIV infection is important, but often the infection is difficult to recognize. We report the case of a 23-year-old man with persistent genital ulceration; all microbiological examinations from the ulcers were negative. HIV-1/2 antibodies were positive, but the HIV-1 Western blot (WB) was indeterminate and HIV-1 p24 antigen was persistently negative, with a low HIV-1 RNA level. One month later, the genital ulcerations disappeared and the WB test showed complete seroconversion; nonetheless HIV p24 antigen remained negative and HIV-RNA was persistently low. HIV-1 proviral DNA was detected by nested polymerase chain reaction (PCR) from the initial ulcers swabs. This case was notable due to genital ulceration being the only sign of primary HIV infection. Furthermore, the serological pattern was unusual, and HIV-RNA was unexpectedly low. This underlines the importance of screening for HIV being infection in the setting of sexually transmitted infections (STIs), and also in cases of atypical STI-like presentations.

[Anaesthesia for HIV-infected patients]

France is one of main countries affected by the HIV-outbreak in Europe with more than 120,000 cases, among which 34,600 patients having developed an AIDS. The antiretroviral combination therapies (combined antiretroviral therapy [cART]) reduced by half the mortality. A low compliance to cART alters the virologic control and increases the morbimortality. If required, the therapeutic break should be the shortest possible, including the whole treatment (to limit the risk of viral resistance). The perioperative care should take into account the underlying conditions. During the preoperative period, the clinical picture could combine various complications: 1: respiratory impairment; 2: impairment of neuronal functions (related to viral factors, host response and environmental factors such as alcohol, drug addiction, HCV co-infection) inducing a cognitive dysfunction or a peripheral neuropathy; 3: lipodystrophy, dyslipidemia and insulin resistance are the main metabolic cART-related side effects, responsible for atherosclerosis and coronaropathy; 4: major nutritional impairment. Anesthesia for HIV patients is almost the same than usual, without HIV-related contraindication to regional anesthesia. Anesthetic drugs can be associated to cART. The main restriction belongs to the protease inhibitors, which could affect the metabolic pathways of opioids, NSAIDs and benzodiazepines (over dosage risks). During the postoperative period, the follow-up should include the thromboembolism prevention (increased risk compared to main people), the cardiovascular side effects, the nutritional status and the continuation of the treatment. Moreover, the psychological status related and a close collaboration with the corresponding physician is critical.

HIV variability in the liver and evidence of possible compartmentalization

There is growing evidence to suggest that HIV may interact with several hepatic cell types; however, evaluation of HIV variability in liver tissue has not been addressed to date. Among 16 HIV-positive individuals examined, nine (56%) had detectable HIV RNA in the liver. The mean CD4 cell count for these nine individuals was 337 cells/mm(3) (range: 0-601), while their mean plasma HIV RNA level was 106,974 copies/ml (range: 1200-320,740). Among individuals in this study with detectable HIV in both the plasma and the liver, the consensus gag nucleotide sequences for each tissue type were different for seven of seven (100%) individuals, while amino acid sequences were distinct for five of seven (71%). Consensus envelope (env) nucleotide and amino acid sequences were also distinct in the plasma and liver tissue for six of six (100%) individuals. Statistical evidence of compartmentalization between HIV in the plasma and in the liver was demonstrated, and multiple liver-specific amino acids were identified that may distinguish HIV variants replicating within the liver. These preliminary data demonstrate that HIV is frequently detectable in the liver of HIV-positive persons at various levels of immunosuppression. Possible compartmentalization may reflect tissue-specific selection pressures that drive viral adaptation to the liver microenvironment and may facilitate interactions with other hepatotropic viruses.

A novel RealTime HIV-1 Qualitative assay for the detection of HIV-1 nucleic acids in dried blood spots and plasma

Abbott RealTime HIV-1 Qualitative is an in vitro real-time PCR assay for detecting HIV-1 nucleic acids in human plasma and dried blood spots (DBS). The assay was designed to be used in diagnosis of HIV-1 infections in pediatric and adult patients, with an emphasis on the applicability in resource-limited settings. Use of DBS facilitates specimen collection from remote areas and transportation to testing laboratories. Small sample input requirement facilitates testing of specimens with limited collection volume. The Abbott RealTime HIV-1 Qualitative assay is capable of detecting HIV-1 group M subtypes A-H, group O and group N samples. HIV-1 virus concentrations detected with 95% probability were 80 copies/mL of plasma using the plasma protocol, and 2469 copies/mL of whole blood using the DBS protocol. The assay detected HIV-1 infection in 13 seroconversion panels an average 10.5 days earlier than an HIV-1 antibody test and 4.9 days earlier than a p24 antigen test. For specimens collected from 6 weeks to 18 months old infants born to HIV-1 positive mothers, assay results using both the DBS and plasma protocols agreed well with the Roche Amplicor HIV-1 DNA Test version 1.5 (95.5% agreement for DBS and 97.8% agreement for plasma).

Biomarkers of immune dysfunction following combination antiretroviral therapy for HIV infection

Combination antiretroviral therapy (cART) has significantly reduced morbidity and mortality of HIV-infected patients, yet their life expectancy remains reduced compared with the general population. Most HIV-infected patients receiving cART have some persistent immune dysfunction characterized by chronic immune activation and premature aging of the immune system. Here we review biomarkers of T-cell activation (CD69, -25 and -38, HLA-DR, and soluble CD26 and -30); generalized immune activation (C-reactive protein, IL-6 and D-dimer); microbial translocation (lipopolysaccharide, 16S rDNA, lipopolysaccharide-binding protein and soluble CD14); and immune dysfunction of specific cellular subsets (T cells, natural killer cells and monocytes) in HIV-infected patients on cART and their relationship to adverse clinical outcomes including impaired CD4 T-cell recovery, as well as non-AIDS clinical events, such as cardiovascular disease.

A Case of Kaposi's Sarcoma during Primary HIV-1 Infection

The majority of cases of Kaposi's sarcoma (KS) occur at low CD4 counts during chronic HIV-1 infection. We present a case of KS which was diagnosed during primary HIV-1 infection. This report aims to draw attention that KS may occur early in the course of HIV-1 infection and that primary HIV-1 infection may rapidly progress to AIDS.

[Prolonged fever: specific issues in the young adult population]

Early studies on prolonged fever date back to the 1960s. Fifty years later, prolonged unexplained fever remains a diagnostic challenge to the general internists. Although the aetiologies of prolonged fevers have not changed much in the general population, the distribution between the various causes is not the same anymore. A regular decrease in infectious and neoplastic causes is noticed whatever the age. Prolonged fevers related to inflammatory disorders and fevers that remain of unknown origin still represent approximately 30 to 50% of the cases. In the young adult population, as in the older patients, prolonged fevers can be attributed to four groups: infection, inflammation, neoplasic and other aetiologies (including drug-related fevers). In the young adult population, the management of prolonged fever presents some specific issues that are the purpose of this review coupled with our own experience. The prognosis of undiagnosed prolonged fever is usually favourable, as a life-threatening aetiology is exceptionally diagnosed during the follow-up if the initial management was complete and accurate.

Extended high viremics: a substantial fraction of individuals maintain high plasma viral RNA levels after acute HIV-1 subtype C infection

OBJECTIVE

The present study addressed two questions: what fraction of individuals maintain a sustained high HIV-1 RNA load after the acute HIV-1C infection peak and how long is a high HIV-1 RNA load maintained after acute HIV-1C infection in this subpopulation?

DESIGN/METHODS

Plasma HIV-1 RNA dynamics were studied in 77 participants with primary HIV-1C infection from African cohorts in Gaborone, Botswana, and Durban, South Africa. HIV-infected individuals who maintained mean viral load of at least 100,000 (5.0 log(10)) copies/ml after 100 days postseroconversion (p/s) were termed extended high viremics. Individuals were followed longitudinally for a median [interquartile range (IQR)] of 573 (226-986) days p/s.

RESULTS

The proportion of extended high viremics was 34% [95% confidence interval (CI) 23-44%] during the period 100-300 days p/s and 19% (95% CI 9-29%) over the period of 200-400 days p/s. The median (IQR) duration of HIV-1 RNA load at least 100,000 copies/ml among extended high viremics was 271 (188-340) days p/s. For the subset with average viral load at least 100,000 copies/ml during 200-400 days p/s, the median (IQR) duration was 318 (282-459) days. The extended high viremics had a significantly shorter time to CD4 cell decline to 350 cells/μl (median: 88 vs. 691 days p/s for those not designated as extended high viremics; P < 0.0001, Gehan-Wilcoxon test).

CONCLUSION

A high proportion of extended high viremics - individuals maintaining high plasma HIV-1 RNA load after acute infection - have been identified during primary HIV-1 subtype C infection. These extended high viremics likely contribute disproportionately to HIV-1 incidence.

Quantification of the relative importance of CTL, B cell, NK cell, and target cell limitation in the control of primary SIV-infection

CD8+ cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, B cells and target cell limitation have all been suggested to play a role in the control of SIV and HIV-1 infection. However, previous research typically studied each population in isolation leaving the magnitude, relative importance and in vivo relevance of each effect unclear. Here we quantify the relative importance of CTLs, NK cells, B cells and target cell limitation in controlling acute SIV infection in rhesus macaques. Using three different methods, we find that the availability of target cells and CD8+ T cells are important predictors of viral load dynamics. If CTL are assumed to mediate this anti-viral effect via a lytic mechanism then we estimate that CTL killing is responsible for approximately 40% of productively infected cell death, the remaining cell death being attributable to intrinsic, immune (CD8+ T cell, NK cell, B cell) -independent mechanisms. Furthermore, we find that NK cells have little impact on the death rate of infected CD4+ cells and that their net impact is to increase viral load. We hypothesize that NK cells play a detrimental role in SIV infection, possibly by increasing T cell activation.

Screening for acute HIV infection in South Africa: finding acute and chronic disease

BACKGROUND

The yield of screening for acute HIV infection among general medical patients in resource-scarce settings remains unclear. Our objective was to evaluate the strategy of using pooled HIV plasma RNA to diagnose acute HIV infection in patients with negative or discordant rapid HIV antibody tests in Durban, South Africa.

METHODS

We prospectively enrolled patients with negative or discordant rapid HIV antibody tests from a routine HIV screening programme in an out-patient department in Durban with an HIV prevalence of 48%. Study participants underwent venipuncture for pooled qualitative HIV RNA, and, if this was positive, quantitative RNA, enzyme immunoassay and Western blot (WB). Patients with negative or indeterminate WB and positive quantitative HIV RNA were considered acutely infected. Those with chronic infection (positive RNA and WB) despite negative or discordant rapid HIV tests were considered to have had false negative rapid antibody tests.

RESULTS

Nine hundred and ninety-four participants were enrolled with either negative (n=976) or discordant (n=18) rapid test results. Eleven [1.1%; 95% confidence interval (CI) 0.6-2.0%] had acute HIV infection, and an additional 20 (2.0%; 95% CI 1.3-3.1%) had chronic HIV infection (false negative rapid test).

CONCLUSIONS

One per cent of out-patients with negative or discordant rapid HIV tests in Durban, South Africa had acute HIV infection readily detectable through pooled serum HIV RNA screening. Pooled RNA testing also identified an additional 2% of patients with chronic HIV infection. HIV RNA screening has the potential to identify both acute and chronic HIV infections that are otherwise missed by standard HIV testing algorithms.

HIV mono-infection is associated with FIB-4 - A noninvasive index of liver fibrosis - in women

BACKGROUND

FIB-4 represents a noninvasive, composite index that is a validated measure of hepatic fibrosis, which is an important indicator of liver disease. To date, there are limited data regarding hepatic fibrosis in women.

METHODS

FIB-4 was evaluated in a cohort of 1227 women, and associations were evaluated in univariate and multivariate regression models among 4 groups of subjects classified by their human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection status.

RESULTS

The median FIB-4 scores were 0.60 in HIV-/HCV- women, 0.83 in HIV-/HCV+ women, 0.86 in HIV+/HCV- women, and 1.30 in HIV+/HCV+ women. In the HIV/HCV co-infected group, multivariate analysis showed that CD4(+) cell count and albumin level were negatively associated with FIB-4 (P <.0001), whereas antiretroviral therapy (ART) was positively associated with FIB-4 score (P =.0008). For the HIV mono-infected group, multivariate analysis showed that CD4(+) cell count (P <.0001) and albumin level (P =.0019) were negatively correlated with FIB-4 score, ART was positively associated with FIB-4 score (P =.0008), and plasma HIV RNA level was marginally associated with FIB-4 score (P =.080). In 72 HIV mono-infected women who were also hepatitis B surface antigen negative, ART naive, and reported no recent alcohol intake, plasma HIV RNA level was associated with increased FIB-4 score (P =.030).

CONCLUSIONS

HIV RNA level was associated with increased FIB-4 score in the absence of hepatitis B, hepatitis C, ART, or alcohol use, suggesting a potential relationship between HIV infection and hepatic fibrosis in vivo. A better understanding of the various demographic and virologic variables that contribute to hepatic fibrosis may lead to more effective treatment of HIV infection and its co-morbid conditions.

Ambiguous nucleotide calls from population-based sequencing of HIV-1 are a marker for viral diversity and the age of infection

The fraction of ambiguous nucleotide calls in bulk sequencing of human immunodeficiency virus type 1 (HIV-1) carries important information on viral diversity and the age of infection. In particular, a fraction of ambiguous nucleotides of >.5% provides evidence against a recent infection event <1 year ago.

Background. The time passed since the infection of a human immunodeficiency virus (HIV)–infected individual (the age of infection) is an important but often only poorly known quantity. We assessed whether the fraction of ambiguous nucleotides obtained from bulk sequencing as done for genotypic resistance testing can serve as a proxy of this parameter.

Methods. We correlated the age of infection and the fraction of ambiguous nucleotides in partial pol sequences of HIV-1 sampled before initiation of antiretroviral therapy (ART). Three groups of Swiss HIV Cohort Study participants were analyzed, for whom the age of infection was estimated on the basis of Bayesian back calculation (n = 3,307), seroconversion (n = 366), or diagnoses of primary HIV infection (n = 130). In addition, we studied 124 patients for whom longitudinal genotypic resistance testing was performed while they were still ART-naïve.

Results. We found that the fraction of ambiguous nucleotides increased with the age of infection with a rate of .2% per year within the first 8 years but thereafter with a decreasing rate. We show that this pattern is consistent with population-genetic models for realistic parameters. Finally, we show that, in this highly representative population, a fraction of ambiguous nucleotides of >.5% provides strong evidence against a recent infection event <1 year prior to sampling (negative predictive value, 98.7%).

Conclusions. These findings show that the fraction of ambiguous nucleotides is a useful marker for the age of infection.

Rapid rise in detection of human papillomavirus (HPV) infection soon after incident HIV infection among South African women

BACKGROUND

It is well established that the prevalence of human papillomavirus (HPV) infection is increased among human immunodeficiency virus (HIV)-positive individuals, but the temporal relationships between these infections are unclear.

METHODS

During a South African cervical cancer screening trial, 5595 women 35-65 years of age were followed up for 36 months; 577 women were HIV positive at enrollment, HIV seroconversion occurred in 123 women, and 4895 women remained HIV negative throughout. Tests for high-risk HPV DNA and cytology were performed on cervical samples, and a colposcopy/biopsy was performed at each visit. The effects of early HIV infection on the risk of HPV infection and HPV-related disease were evaluated.

RESULTS

Among seroconverters, HPV infection prevalence was 20.3% before seroconversion, 23.6% at seroconversion (P = .4), and 49.1% after seroconversion (P = .01). Seroconverters had significantly lower HPV infection prevalence than women with prevalent HIV infection before and at seroconversion (41.8% and 45.9%, respectively) but had similar HPV infection prevalence to women with prevalent HIV infection after seroconversion (49.4%). HIV seroconversion was associated with newly detected HPV infection (adjusted hazard ratio [AHR], 4.02; 95% confidence interval [CI], 2.26-7.13) and increased risk of low-grade cytological abnormalities (AHR, 2.53; 95% CI, 1.16-5.51) compared with HIV-negative women.

CONCLUSION

Detection of HPV infection increases rapidly within the first years after HIV seroconversion, suggesting that mucosal immune dysfunction occurring at an early stage of HIV infection may influence HPV-related diseases.

Primary HIV infection with acute transverse myelitis

Primary HIV infection (PHI) is associated with various neurological disorders. However, acute transverse myelitis (ATM) complicating PHI has not been reported after the introduction of the combination antiretroviral therapy (cART). We encountered one patient with known PHI with clinical presentation of ATM. Treatment with cART and corticosteroids successfully improved symptoms, and no recurrence was noted after discontinuation of cART. In conclusion, concurrent use of cART and corticosteroids was effective against PHI accompanied by ATM and could be withdrawn after improvement of ATM.

Potential of polymeric nanoparticles in AIDS treatment and prevention

IMPORTANCE OF THE FIELD

Acquired immunodeficiency syndrome (AIDS) remains one of the greatest challenges in public health. The AIDS virus is now responsible for > 2.5 million new infections worldwide each year. Despite significant advances in understanding the mechanism of viral infection and identifying effective treatment approaches, the search for optimum treatment strategies for AIDS remains a major challenge. Recent advances in the field of drug delivery have provided evidence that engineered nanosystems may contribute to the enhancement of current antiretroviral therapy.

AREAS COVERED IN THIS REVIEW

This review describes the potential of polymeric nanoparticle-based drug delivery systems in the future treatment of AIDS. Polymeric nanoparticles have been developed to improve physicochemical drug characteristics (by increasing drug solubility and stability), to achieve sustained drug release profile, to provide targeting to the cellular and anatomic human immunodeficiency virus (HIV) latent reservoirs and to be applied as an adjuvant in anti-HIV vaccine formulations.

WHAT THE READER WILL GAIN

The insight that will be gained is knowledge about the progress in the development of polymeric nanoparticle-based drug delivery systems for antiretroviral drugs as alternative for AIDS treatment and prevention.

TAKE HOME MESSAGE

The advances in the field of targeted drug delivery can result in more efficient strategies for AIDS treatment and prevention.

The global security perspective on the effects of executive cognitive function on complex behavioral screening intervention and HIV/AIDS

The purpose of this quantitative study is to understand the global security perspective on the effects of executive cognitive function (ECF) on Complex Behavioral Screening Intervention and HIV/AIDS. The HIV/AIDS pandemic is as much a social, political, economic, and cultural problem as a biomedical one. HIV/AIDS is associated centrally with the collapse not just of communities and families but potentially of states, with some of the largest public health interventions ever and enormous questions about governance, a huge population of orphans, and deep questions about intergenerational relations and cultural transmission. This study also is to develop a screening instrument that improves quality of life for individuals with executive cognitive impairments and behavior problems in our communities and the global society.

Clinical management of acute HIV infection: best practice remains unknown

Best practice for the clinical management of acute human immunodeficiency virus (HIV) infection remains unknown. Although some data suggest possible immunologic, virologic, or clinical benefit of early treatment, other studies show no difference in these outcomes over time, after early treatment is discontinued. The literature on acute HIV infection is predominantly small nonrandomized studies, which further limits interpretation. As a result, the physician is left to grapple with these uncertainties while making clinical decisions for patients with acute HIV infection. Here we review the literature, focusing on the potential advantages and disadvantages of treating acute HIV infection outlined in treatment guidelines, and summarize the presentations on clinical management of acute HIV infection from the 2009 Acute HIV Infection Meeting in Boston, Massachusetts.

Standard of care: promoting antiretroviral adherence in clinical care

Although there has long been demand for programs and procedures that support or enhance adherence to antiretroviral therapy (ART) among HIV+ patients, there is scant evidence about the extent to which medical clinics have been able to incorporate adherence interventions into their standard care. A survey of clinical care settings in New York and Connecticut indicated that the current standard of care is to provide only minimal levels of adherence services, with ad hoc adherence support being offered on an as-needed basis, often by overburdened primary care staff. These results suggest a strong need for the development of ART adherence interventions that are not only easily translatable to real-life clinical settings, but also offer an organized compendium of resources for HIV+ patients, from initiation to maintenance.

Role of acute and early HIV infection in the sexual transmission of HIV

PURPOSE OF REVIEW

Acute HIV infection (AHI), the earliest period after HIV acquisition, is only a few weeks in duration. In this brief period, the concentration of HIV in blood and genital secretions is extremely high, increasing the probability of HIV transmission. Although a substantial role of AHI in the sexual transmission of HIV is biologically plausible, the significance of AHI in the epidemiological spread of HIV remains uncertain.

RECENT FINDINGS

AHI is diagnosed by detecting viral RNA or antigen in the blood of persons who are HIV seronegative. Depending on the setting, persons with AHI represent between 1 and 10% of persons with newly diagnosed HIV infection. The high concentration of virus during AHI leads to increased infectiousness, possibly as much as 26 times greater than during chronic infection. In mathematical models, the estimated proportion of transmission attributed to AHI has varied considerably, depending on model structure, model parameters, and the population. Key determinants include the stage of the HIV epidemic and the sexual risk profile of the population.

SUMMARY

Despite its brief duration, AHI plays a disproportionate role in the sexual transmission of HIV infection. Detection of persons with AHI may provide an important opportunity for transmission prevention.

Human hematopoietic stem/progenitor cells modified by zinc-finger nucleases targeted to CCR5 control HIV-1 in vivo

CCR5 is the major HIV-1 co-receptor, and individuals homozygous for a 32-bp deletion in CCR5 are resistant to infection by CCR5-tropic HIV-1. Using engineered zinc-finger nucleases (ZFNs), we disrupted CCR5 in human CD34(+) hematopoietic stem/progenitor cells (HSPCs) at a mean frequency of 17% of the total alleles in a population. This procedure produces both mono- and bi-allelically disrupted cells. ZFN-treated HSPCs retained the ability to engraft NOD/SCID/IL2rgamma(null) mice and gave rise to polyclonal multi-lineage progeny in which CCR5 was permanently disrupted. Control mice receiving untreated HSPCs and challenged with CCR5-tropic HIV-1 showed profound CD4(+) T-cell loss. In contrast, mice transplanted with ZFN-modified HSPCs underwent rapid selection for CCR5(-/-) cells, had significantly lower HIV-1 levels and preserved human cells throughout their tissues. The demonstration that a minority of CCR5(-/-) HSPCs can populate an infected animal with HIV-1-resistant, CCR5(-/-) progeny supports the use of ZFN-modified autologous hematopoietic stem cells as a clinical approach to treating HIV-1.

Innate immune recognition and activation during HIV infection

The pathogenesis of HIV infection, and in particular the development of immunodeficiency, remains incompletely understood. Whichever intricate molecular mechanisms are at play between HIV and the host, it is evident that the organism is incapable of restricting and eradicating the invading pathogen. Both innate and adaptive immune responses are raised, but they appear to be insufficient or too late to eliminate the virus. Moreover, the picture is complicated by the fact that the very same cells and responses aimed at eliminating the virus seem to play deleterious roles by driving ongoing immune activation and progressive immunodeficiency. Whereas much knowledge exists on the role of adaptive immunity during HIV infection, it has only recently been appreciated that the innate immune response also plays an important part in HIV pathogenesis. In this review, we present current knowledge on innate immune recognition and activation during HIV infection based on studies in cell culture, non-human primates, and HIV-infected individuals, and discuss the implications for the understanding of HIV immunopathogenesis.

[HIV infection in different age groups: Potential implications for prevention. CoRIS Cohort, Spain, 2004-2008]

BACKGROUND AND OBJECTIVE

To describe the characteristics of HIV infected adults according to their age at recruitment in CoRIS.

PATIENTS AND METHODS

Analysis of an open, prospective, multicentric cohort of HIV+ adults without previous antiretroviral treatment, attended for the first time from January/2004 to November/2008, in 28 Spanish hospitals (CoRIS). We analyzed their characteristics at recruitment and the distribution of AIDS defining illnesses (ADI) prior to cohort entry and during follow up, according to their age at recruitment. Delayed diagnosis was defined as a patient with AIDS diagnosis and/or CD4+ cell count lower than 200 cells/microl within the first year after HIV diagnosis.

RESULTS

Of 4,418 patients included, 30.4% were < or =30 years old, 60.6% between 31 and 50 and 8.9% older than 50 at cohort entry; 31.6% of patients were immigrants (44.1% in the youngest group), 79.6% had been sexually transmitted and 15.2% had an AIDS diagnosis at cohort entry (28.1% between those older than 50). In 34.6% of cases there was a late diagnosis (53.3% in the oldest group). The ADIs varied according to age; tuberculosis was more frequent in the youngest. Pneumocystis jiroveci pneumonia, progressive multifocal leukoencephalopathy, HIV related encephalopathy, recurrent pneumonia and primary lymphoma of brain were more frequent among the oldest.

CONCLUSIONS

The immunological characteristics and the distribution of ADIs varied according to age. The proportion of late diagnosis was unacceptably high, suggesting the need of specific interventions designed to promote earlier diagnosis.

Despite being highly diverse, immunovirological status strongly correlates with clinical symptoms during primary HIV-1 infection: a cross-sectional study based on 674 patients enrolled in the ANRS CO 06 PRIMO cohort

OBJECTIVES

To analyse immunovirological status during primary HIV-1 infection (PHI) according to contemporary clinical status and time since infection.

METHODS

Plasma HIV-RNA and peripheral blood mononuclear cell (PBMC) HIV-DNA levels and CD4 cell counts were determined at enrolment in the ANRS PRIMO cohort. Time since infection was estimated based on both the number of antibodies on western blot at enrolment (0-1, 2-4 or > or =5 specific antibodies) and the estimated interval between infection and enrolment based on clinical and epidemiological features. Patients were classified according to the presence or absence of clinical symptoms at enrolment.

RESULTS

Between 1996 and 2006, 674 patients were enrolled an estimated median of 47 days after infection. Median marker values were as follows: HIV-RNA 5.10 log(10) copies/mL (range <1.70-8.33); HIV-DNA 3.30 log(10) copies/10(6) PBMCs (<1.84-4.93); and 506 CD4 cells/mm(3) (40-1542). Median HIV-RNA and PBMC HIV-DNA levels were significantly higher in patients with 0 or 1 specific antibody (n = 71) than in patients with 2-4 (n = 228) or > or =5 antibodies (n = 375). Symptomatic patients had significantly higher HIV-RNA and PBMC HIV-DNA levels and lower CD4 cell counts. However, 10% of symptomatic patients recruited shortly after infection had favourable immunovirological status.

CONCLUSIONS

Plasma HIV-RNA, PBMC HIV-DNA and CD4 cell count values were highly diverse and correlated strongly with clinical status during PHI. Early diagnosis was not always associated with severe PHI. Combining PBMC HIV-DNA with HIV-RNA, CD4 cell count and clinical symptoms would have allowed identification of 179 patients (26.5%) at high risk of rapid disease progression who did not meet current guidelines for early treatment initiation.

A case of seronegative HIV-1 infection

Patients infected with human immunodeficiency virus type 1 (HIV-1) typically seroconvert within weeks of primary infection. In rare cases, patients do not develop antibodies against HIV-1 despite demonstrable infection. We describe here a human leukocyte antigen (HLA)-B*5802-positive individual who presented with acquired immune deficiency syndrome despite repeatedly negative HIV-1 antibody screening test results. Phylogenetic analysis of env clones revealed little sequence diversity, and weak HIV-1-specific CD8(+) T cell responses were present to Gag epitopes. The patient seroconverted after immune reconstitution during receipt of highly active antiretroviral therapy. Lack of an antibody response to HIV-1 is rare and appears to be due to a defect in HIV-1-specific immunity rather than infection with attenuated virus.

When and why to start antiretroviral therapy?

The question about when to start antiretroviral therapy in HIV-1-infected patients has been debated since the discovery of the first antiretroviral agent (zidovudine) back in 1986 and has been fuelled by the introduction of highly active combined antiretroviral therapy (cART) 10 years later in 1996. The dramatic improvement in the mortality rate associated with cART supported the principle of 'hitting early and hard', but the initial enthusiasm was quickly tempered by the realization of the inconveniences and the short- to mid-term treatment-related toxicities, including lipoatrophy. In 2009, cART can be very simple and generally well tolerated. All patients with a CD4+ T cell count of <350 cells/mm(3) should receive cART. Moreover, several cohort studies have convincingly demonstrated a significant reduction of AIDS- and non-AIDS-related events when cART is initiated at >350 CD4+ T lymphocytes/mm(3), and even at >500 CD4+ T lymphocytes/mm(3). Also, cART may be considered when there are associated co-morbidities, such as hepatitis C. In addition to individual benefits, an undetectable viral load in response to cART is associated with a substantial reduction in the likelihood of HIV transmission. This can benefit seronegative sexual partners and can potentially diminish the number of new infections, especially if those infected persons unaware of their situation can be identified and advised to initiate cART. Willingness to be treated and to adhere to the prescribed medication still remains the key to success.

Identifying people with acute HIV infection: demographic features, risk factors, and use of health care among individuals with AHI in North Carolina

Identifying and counseling individuals with Acute HIV Infection (AHI) offers a critical opportunity to avert preventable HIV transmission, however, opportunities to recognize these individuals may be missed. We surveyed 32 adults diagnosed with AHI during voluntary HIV testing from 1/1/03 to 2/28/05 in publicly funded testing sites in NC to describe their clinical, social, and behavioral characteristics. Eighty-one percent of participants were men; 59% were African American. Seventy-five percent experienced symptoms consistent with acute retroviral syndrome; although 83% sought medical care for these symptoms, only 15% were appropriately diagnosed at that initial medical visit, suggesting opportunities to diagnose these individuals earlier were missed. Eighty-five percent of the men engaged in sex with men. More than 50% of the participants thought they were infected with HIV by a steady partner. This study yields important information to assist in identifying populations at risk for or infected with AHI and designing both primary and secondary prevention interventions.

Performance of an immunoassay at detecting recent infection among reported HIV diagnoses

INTRODUCTION

An enzyme immunoassay to detect recent HIV-1 infection (EIA-RI) of less than 6 months is routinely performed on diagnoses reported to the National HIV case surveillance in France. We assessed the performance of the EIA-RI infection on this country population scale by measuring its agreement with other indicators of time since infection that were obtained through clinical, biological or testing history recorded on the surveillance reporting form.

METHODS

We used data from the National HIV case surveillance from its debut in March 2003 to June 2007. Infection within 6 months was defined as a negative test reported within 6 months prior to diagnosis. We further ascertained this definition by adding information about of a symptomatic primary infection or biological evidence of recent seroconversion. Infection established for more than 6 months was defined when a positive test had occurred more than 6 months prior to the reported diagnosis.

RESULTS

Time since infection could be ascertained in 6782 of 15, 331 (44.2%) HIV diagnoses. Assay sensitivity and specificity were 73.8 and 83.7%, respectively. Among the 1940 cases originating from Sub-Saharan Africa, sensitivity and specificity were 54.1 and 90.8%, respectively.

DISCUSSION

Assessment of the performance of the EIA-RI on a large and heterogeneous population revealed two major findings--significant discrepancies in timing from infection near the 180-day cutoff, and a performance that depends on the geographic origin of patients. This has implications for estimating the assay window period and in the perspective of incidence estimation from HIV case surveillance.

The utilization of humanized mouse models for the study of human retroviral infections

The development of novel techniques and systems to study human infectious diseases in both an in vitro and in vivo settings is always in high demand. Ideally, small animal models are the most efficient method of studying human afflictions. This is especially evident in the study of the human retroviruses, HIV-1 and HTLV-1, in that current simian animal models, though robust, are often expensive and difficult to maintain. Over the past two decades, the construction of humanized animal models through the transplantation and engraftment of human tissues or progenitor cells into immunocompromised mouse strains has allowed for the development of a reconstituted human tissue scaffold in a small animal system. The utilization of small animal models for retroviral studies required expansion of the early CB-17 scid/scid mouse resulting in animals demonstrating improved engraftment efficiency and infectivity. The implantation of uneducated human immune cells and associated tissue provided the basis for the SCID-hu Thy/Liv and hu-PBL-SCID models. Engraftment efficiency of these tissues was further improved through the integration of the non-obese diabetic (NOD) mutation leading to the creation of NODSCID, NOD/Shi-scid IL2rγ^-/-, and NOD/SCID β2-microglobulin^null animals. Further efforts at minimizing the response of the innate murine immune system produced the Rag2^-/-γ_c^-/- model which marked an important advancement in the use of human CD34+ hematopoietic stem cells. Together, these animal models have revolutionized the investigation of retroviral infections in vivo.

Postinfection passive transfer of KD-247 protects against simian/human immunodeficiency virus-induced CD4+ T-cell loss in macaque lymphoid tissue

BACKGROUND

Preadministration of high-affinity humanized anti-HIV-1 mAb KD-247 by passive transfer provides sterile protection of monkeys from heterologous chimeric simian/human immunodeficiency virus infection.

METHODS

Beginning 1 h, 1 day, or 1 week after simian/human immunodeficiency virus-C2/1 challenge (20 50% tissue culture infective dose), mature, male cynomolgus monkeys received multiple passive transfers of KD-247 (45 mg/kg) on a weekly basis for approximately 2 months. Concentrations and viral loads were measured in peripheral blood, and CD4 T-cell counts were examined in both peripheral blood and various lymphoid tissues.

RESULTS

Pharmacokinetic examination revealed similar plasma maintenance levels ranging from 200 to 500 microg/ml of KD-247 in the three groups. One of the six monkeys given KD-247 could not maintain these concentrations, and elicitation of anti-KD-247 idiotype antibody was suggested. All monkeys given KD-247 exhibited striking postinfection protection against both CD4 T-cell loss in various lymphoid tissues and atrophic changes in organs compared with control group animals treated with normal human immunoglobulin G. The KD-247-treated groups were also partially protected against plasma viral load elevation in peripheral blood samples, although the complete protection previously reported with preadministration of this mAb was not achieved.

CONCLUSION

Postinfection passive transfer of humanized mAb KD-247 with strong neutralizing capacity against challenged virus simian/human immunodeficiency virus-C2/1 protected CD4 T cells in lymphoid organs.

Primary HIV-1 infection among infants in sub-Saharan Africa: HPTN 024

OBJECTIVES

Our objectives were to assess clinical signs and diagnoses associated with primary HIV-1 infection among infants.

METHODS

We analyzed data from a clinical trial (HIV Prevention Trials Network Protocol 024) in sub-Saharan Africa. Study visits were conducted at birth, at 4-6 weeks, and at 3, 6, 9, and 12 months. The study population comprised live born, singleton, first-born infants of HIV-1-infected women with negative HIV-1 RNA assays who were still breastfeeding at 4-6 weeks.

RESULTS

Of 1317 HIV-1-exposed infants, 84 became HIV-1 infected after 4-6 weeks and 1233 remained uninfected. There were 102 primary and 5650 nonprimary infection visits. The most common signs were cough and diarrhea, and the most common diagnoses were malaria and pneumonia. Primary infection was associated with significantly increased odds of diarrhea [odds ratio (OR) = 2.4], pneumonia (OR = 3.5), otitis media (OR = 3.1), and oral thrush (OR = 2.9). For the clinical signs and diagnoses evaluated, sensitivity was low (1%-16.7%) and specificity was high (88.2%-99%). Positive predictive values ranged from 0.1%-1.4%. Negative predictive values ranged from 28.0%-51.1%.

CONCLUSIONS

Certain clinical signs and diagnoses, although more common during primary HIV-1 infection, had low sensitivity and high specificity. Efforts to expand access to laboratory assays for the diagnosis of primary HIV-1 infection among infants of HIV-1-infected women should be emphasized.

HIV infection and the central nervous system: a primer

The purpose of this brief review is to prepare readers who may be unfamiliar with Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS) and the rapidly accumulating changes in the epidemic by providing an introduction to HIV disease and its treatment. The general concepts presented here will facilitate understanding of the papers in this issue on HIV-associated neurocognitive disorders (HAND). Toward that end, we briefly review the biology of HIV and how it causes disease in its human host, its epidemiology, and how antiretroviral treatments are targeted to interfere with the molecular biology that allows the virus to reproduce. Finally, we describe what is known about how HIV injures the nervous system, leading to HAND, and discuss potential strategies for preventing or treating the effects of HIV on the nervous system.

Risk-based HIV testing in South Carolina health care settings failed to identify the majority of infected individuals

To provide evidence of large numbers of missed opportunities for early HIV diagnosis we designed a retrospective cohort study linking surveillance data from the South Carolina HIV/AIDS Reporting System to a statewide all payer health care database. We determined visits and diagnoses occurring before the date of the first positive HIV test and medical encounters were categorized to distinguish visits that were likely versus unlikely to have prompted an HIV test. Of the 4117 HIV-positive individuals newly diagnosed between 2001 and 2005, 3021 (73.4%) visited a South Carolina health care facility one or more times prior to testing HIV positive. Of these 3021, 1311 (43.4%) were late testers, and 1425 (47.2%) were early testers. Females were less likely than males to be late testers (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.45-0.68), blacks were more likely than whites to be late testers (OR 1.37, 95% CI 1.10-1.71), and persons 50 years of age and older more likely to be late testers (OR 7.16, 95% CI 3.84-13.37). A total of 78.8% of the 13,448 health care visits for both late and early testers were for health care diagnoses unlikely to prompt an HIV test. These findings underscore the need for more routine HIV testing of adults and adolescents visiting health care facilities in order to facilitate early diagnosis.

Oral complications of HIV disease

Oral lesions are among the early signs of HIV infection and can predict its progression to acquired immunodeficiency syndrome (AIDS). A better understanding of the oral manifestations of AIDS in both adults and children has implications for all health care professionals. The knowledge of such alterations would allow for early recognition of HIV-infected patients. The present paper reviews epidemiology, relevant aspects of HIV infection related to the mouth in both adults and children, as well as current trends in antiretroviral therapy and its connection with orofacial manifestations related to AIDS.

Viral load and CD4+ T-cell dynamics in primary HIV-1 subtype C infection

BACKGROUND

Most knowledge of primary HIV-1 infection is based on subtype B studies, whereas the evolution of viral parameters in the early phase of HIV-1 subtype C infection is not well characterized.

METHODS

The kinetics of viral RNA, proviral DNA, CD4+ T-cell count, and subsets of CD4+ T cells expressing CCR5 or CXCR4 were characterized in 8 acute and 62 recent subtype C infections over the first year postseroconversion.

RESULTS

The viral RNA peak was 6.25 +/- 0.92 log10 copies per milliliter. After seroconversion, heterogeneity among acute cases was evident by patterns of change in viral load and CD4+ T-cell count over time. The patterns were supported by the rate of viral RNA decline from peak (P = 0.022), viral RNA means (P = 0.005), CD4 levels (P < 0.001), and CD4 decline to 350 (P = 0.011) or 200 (P = 0.046). Proviral DNA had no apparent peak and its mean was 2.59 +/- 0.69 log10 per 106 peripheral blood mononuclear cell. In recent infections, viral RNA set point was 4.00 +/- 0.97 log10 and viral RNA correlated inversely with CD4+ T cells (P < 0.001) and directly with proviral DNA (P < 0.001).

CONCLUSIONS

Distinct patterns of viral RNA evolution may exist shortly after seroconversion in HIV-1 subtype C infection. The study provides better understanding of the early phase of subtype C infection.

[Convulsions in the operating room in a man with AIDS]

More than 50 million individuals are infected by the human immunodeficiency virus (HIV), and it is estimated that as many as 25% of them will require surgery. The anesthesiologist must be familiar with the implications of this disease for multiorgan failure and opportunistic infections. Above all, the effects of antiretroviral agents on anesthetics must be understood. We describe the case of an HIV-infected man at risk for difficult intubation who experienced convulsions in the operating room.