SARS-COV-2 Infection in People Living with HIV: Experience from a Tertiary Hospital in Madrid.

Since SAR-COV-2 infection emerged and spread worldwide, little is known about its impact on people living with human immunodeficiency virus (HIV). We performed a single-center retrospective study to describe the potential particularities and risk factors for respiratory failure (RF) in that population. This single-center retrospective study included patients infected with HIV, whose current follow-up is run in this center, above18 years of age, with diagnosis of SARS-CoV-2 infection between March 5, 2020 and April 15, 2021. We collected data regarding HIV immunological and virological status, main epidemiological characteristics, as well as those conditions considered to potentially influence in SARS-CoV-2 evolution; and clinical, microbiological, radiological, respiratory status, and survival concerning coronavirus disease 2019 (COVID-19). We compared all that, for patients with and without RF and performed a logistic regression for suspected risk factors for RF. One hundred seventy-seven HIV patients were diagnosed from COVID-19 (mean age 53.8 years, 81.3% male). At diagnosis, 95.5% were receiving ART and 91.3% had undetectable viral load, with median CD4 count of 569 cells/µL. One hundred thirty-eight patients (78.4%) had symptoms, 44 (25%) developed RF and 53 (31%) developed bilateral pneumonia. The most commonly used treatments were: steroids (26.7%) and hydroxychloroquine (13.1%). When comparing patients with and without RF, we found statistically significant differences for 20 of the analyzed variables such as age (p < .001) and CD4 (p 0.002), and route of HIV transmission by intravenous drug users IVDU (p 0.002) were determined. In multivariate analysis, age [odds ratio (OR) 1.095] and CD4 count less than 350 cells/µL (OR 3.36) emerged as risk factor for RF. People living with HIV whose CD4 count is <350 cells are at higher risk of developing RF when infected by SARS-CoV-2.

Clinical course of severe patients with COVID-19 treated with tocilizumab: report from a cohort study in Spain.

Background: We report the long-term outcomes, changes in laboratory parameters, the incidence of secondary nosocomial infections and treatment cost of a Spanish cohort of patients with severe COVID-19 that received tocilizumab (TCZ).Methods: Retrospective cohort of PCR confirmed adult patients who received TCZ from March 1 to 24, 2020 in a tertiary hospital was analyzed. Patients were followed up until 10 May 2020.Results: We included 162 patients (median age 64 years; 70.4% male). At time of TCZ administration, 48.1% of patients were on invasive mechanical ventilation (IMV). Over a median follow-up of 53 days, 46.9% of patients were discharge in good conditions and 19.8% were still hospitalized. The overall mortality was 33.3%, being higher in patients on IMV than those who did not (46.2% vs 26.7%, P < 0.001). A significant improvement in the lymphocyte count, C-reactive protein, lactate dehydrogenase, and D-dimer was observed. Overall, 43.2% patients presented nosocomial infections, causing death in 8%. Infections were more prevalent in ICU units (63.0% vs 17.1%, P < 0.001). The total cost of TCZ was €371,784.Conclusions: Among the patients who used TCZ, one third died, regardless the improvement in some inflammatory biomarkers. The incidence of secondary nosocomial infections was high.

Self-rated health among people living with HIV in Spain in 2019: a cross-sectional study.

BACKGROUND: HIV infection has become a chronic disease and well-being of people living with HIV (PLHIV) is now of particular concern. The objectives of this paper were to describe self-rated health among PLHIV, on ART and on ART virally suppressed and to analyse its determinants. METHODS: Data were obtained from a second-generation surveillance system based on a cross-sectional one-day survey in public hospitals. Epidemiological and clinical data were collected among HIV-infected inpatients and outpatients receiving HIV-related care the day of the survey in 86 hospitals in 2019. Self-rated health was measured using a question included in the National Health Survey: "In the last 12 months, how would you rate your health status?" an ordinal variable with five categories (very good, good, moderate, bad and very bad). For the analysis, these responses were dichotomized into two categories: 1 = very good/good and 0 = moderate, bad or very bad health status. Factors associated with very good/good self-rated health were estimated using logistic regression. RESULTS: Of 800 PLHIV, 67.5% perceived their health as very good/good, 68.4% among PLHIV on ART and 71.7% of those virally suppressed. Having university education (adjusted odds ratio (aOR):2.1), being unemployed (aOR:0.3) or retired (aOR:0.2), ever being diagnosed of AIDS (aOR:0.6), comorbidities (aOR:0.3), less than 2 year since HIV diagnosis (aOR:0.3) and not receiving ART (aOR:0.3) were associated with good self-rated health. Moreover, among PLHIV on ART, viral load less than 200 copies (aOR:3.2) were related to better perceived health. Bad adherence was inversely associated with good self-rated health among PLHIV on ART (aOR:0.5) and of those virally suppressed (aOR:0.4). CONCLUSIONS: Nearly seven in 10 PLHIV in Spain considered their health status as very good/good, being higher among virally suppressed PLHIV. Both demographic and clinical determinants affect quality of life.

Frailty, markers of immune activation and oxidative stress in HIV infected elderly.

People living with HIV-1 experience an accelerated aging due to the persistent and chronic activation of the immune system. This phenomenon conduces to immune exhaustion and precipitate immunosenescence. In general, frailty is defined as a syndrome of physiological degeneration in the elderly. Circulating naïve and memory T cells were studied by flow cytometry in non-frail and frail HIV-1-infected groups. Thymopoiesis, cell activation, senescence and cell proliferation were analyzed by CD31, HLA-DR/CD38, CD28/CD57 and Ki-67 expression, respectively. Plasma levels of sCD14 and MDA were measured by ELISA. Frail infected individuals showed a reduced number of memory T cells, both CD4+ and CD8+ populations. Activated CD3+CD4+HLA-DR+ T cells were lower in frail individuals, and directly correlated with CD3+CD8+HLA-DR+ and CD8M cells. Senescent CD8+CD28-CD57+ cells were reduced in frail HIV-1 infected individuals and inversely correlated with CD8RTE, CD8N and CD3+CD4+HLA-DR+. Higher plasma levels of sCD14 and MDA were found in HIV-1 infected frail individuals. Our data show association among frailty, markers of immune activation and oxidative stress. Understanding the immune mechanisms underlying frailty status in HIV-1 population is of high relevance not only for the prediction of continuing longevity but also for the identification of potential strategies for the elderly.

Comparison of Safety and Vector-Specific Immune Responses in Healthy and HIV-Infected Populations Vaccinated with MVA-B.

There are few studies comparing the safety and immunogenicity of the same HIV immunogen in healthy volunteers and HIV-infected individuals. We analyzed demographics, adverse events (AEs), and immunogenicity against vaccinia virus in preventive (RISVAC02, n = 24 low-risk HIV-negative volunteers) and therapeutic (RISVAC03, n = 20 successfully treated chronically HIV-1-infected individuals) vaccine phase-I clinical trials that were performed with the same design and the same immunogen (modified vaccinia virus Ankara-B: MVA-B). Total AEs were significantly higher in HIV-infected patients (mean AEs/patient 6.6 vs. 12.8 (p < 0.01)). Conversely, the number of AEs related to vaccination (AEsRV) was similar between both groups. No grade III or IV AEsRV were observed in either clinical trial. Regarding the immunogenicity, the proportion of anti-vaccinia virus antibody responders was similar in both studies. Conversely, the magnitude of response was significantly higher in HIV-infected patients (median binding antibodies at w8 267 vs. 1600 U/mL (p = 0.002) and at w18 666 vs. 3200 U/mL (p = 0.003)). There was also a trend towards higher anti-vaccinia virus neutralizing activity in HIV-infected individuals (proportion of responders 37% vs. 63% (p = 0.09); median IC50 32 vs. 64 (p = 0.054)). This study confirms the safety of MVA-B independent of HIV serostatus. HIV-infected patients showed higher immune responses against vaccinia virus.

Virological Outcome Measures During Analytical Treatment Interruptions in Chronic HIV-1-Infected Patients.

BACKGROUND: Analytical treatment interruptions (ATIs) are essential in research on HIV cure. However, the heterogeneity of virological outcome measures used in different trials hinders the interpretation of the efficacy of different strategies. METHODS: We conducted a retrospective analysis of viral load (VL) evolution in 334 ATI episodes in chronic HIV-1-infected patients collected from 11 prospective studies. Quantitative (baseline VL, set point, delta set point, VL, and delta VL at given weeks after ATI, peak VL, delta peak VL, and area under the rebound curve) and temporal parameters (time to rebound [TtR], set point, peak, and certain absolute and relative VL thresholds) were described. Pairwise correlations between parameters were analyzed, and potential confounding factors (sex, age, time of known HIV infection, time on ART, and immunological interventions) were evaluated. RESULTS: The set point was lower than baseline VL (median delta set point, -0.26; P < .001). This difference was >1 log10 copies/mL in 13.9% of the cases. The median TtR was 2 weeks; no patients had an undetectable VL at week 12. The median time to set point was 8 weeks: by week 12, 97.4% of the patients had reached the set point. TtR and baseline VL were correlated with most temporal and quantitative parameters. The variables independently associated with TtR were baseline VL and the use of immunological interventions. CONCLUSIONS: TtR could be an optimal surrogate marker of response in HIV cure strategies. Our results underline the importance of taking into account baseline VL and other confounding factors in the design and interpretation of these studies.

Safety and vaccine-induced HIV-1 immune responses in healthy volunteers following a late MVA-B boost 4 years after the last immunization.

BACKGROUND: We have previously shown that an HIV vaccine regimen including three doses of HIV-modified vaccinia virus Ankara vector expressing HIV-1 antigens from clade B (MVA-B) was safe and elicited moderate and durable (1 year) T-cell and antibody responses in 75% and 95% of HIV-negative volunteers (n = 24), respectively (RISVAC02 study). Here, we describe the long-term durability of vaccine-induced responses and the safety and immunogenicity of an additional MVA-B boost. METHODS: 13 volunteers from the RISVAC02 trial were recruited to receive a fourth dose of MVA-B 4 years after the last immunization. End-points were safety, cellular and humoral immune responses to HIV-1 and vector antigens assessed by ELISPOT, intracellular cytokine staining (ICS) and ELISA performed before and 2, 4 and 12 weeks after receiving the boost. RESULTS: Volunteers reported 64 adverse events (AEs), although none was a vaccine-related serious AE. After 4 years from the 1st dose of the vaccine, only 2 volunteers maintained low HIV-specific T-cell responses. After the late MVA-B boost, a modest increase in IFN-γ T-cell responses, mainly directed against Env, was detected by ELISPOT in 5/13 (38%) volunteers. ICS confirmed similar results with 45% of volunteers showing that CD4+ T-cell responses were mainly directed against Env, whereas CD8+ T cell-responses were similarly distributed against Env, Gag and GPN. In terms of antibody responses, 23.1% of the vaccinees had detectable Env-specific binding antibodies 4 years after the last MVA-B immunization with a mean titer of 96.5. The late MVA-B boost significantly improved both the response rate (92.3%) and the magnitude of the systemic binding antibodies to gp120 (mean titer of 11460). HIV-1 neutralizing antibodies were also enhanced and detected in 77% of volunteers. Moreover, MVA vector-specific T cell and antibody responses were boosted in 80% and 100% of volunteers respectively. CONCLUSIONS: One boost of MVA-B four years after receiving 3 doses of the same vaccine was safe, induced moderate increases in HIV-specific T cell responses in 38% of volunteers but significantly boosted the binding and neutralizing antibody responses to HIV-1 and to the MVA vector. TRIAL REGISTRATION: ClinicalTrials.gov NCT01923610.

Frailty and physical function in older HIV-infected adults.

Background and Objectives: HIV patients have seen accelerated ageing. Our objective was to determine the prevalence of frailty, to evaluate factors associated with frailty and to evaluate physical function in older HIV-infected adults. Design: this was a cross-sectional study. Setting: outpatient clinics of two public university hospitals in Madrid (Spain). Methods: frailty was defined according to the criteria of Fried: shrinking, weakness, poor endurance and energy, slowness and low physical activity level, being frail those who met at least three criteria, prefrail one or two criteria and robust when they met no criteria. Physical function was assessed using standardised methods. Results: we evaluated 117 HIV-infected patients. Mean age was 61.3 ([standard deviation] 6.87) years. All patients were on antiretroviral therapy. Median current CD4+ T-cell count was 638 (144-1871) cells/µl, and median CD4/CD8 ratio was 0.79 (0.00-3.62). The prevalence of frailty was 15.4%, and that of prefrailty was 52.1%. In the multivariate analyses depressive symptoms (OR [95% CI], 9.20 [2.17-39.05]) and CD4/CD8 ratio (OR 0.11 [0.02-0.61]) were associated with frailty. Even though 100% of the patients were able to walk and perform basic activities of daily life independently, functional impairment was high (20% slow gait and 55% Short Physical Performance Battery ≤9). Conclusions: HIV-infected patients aged ≥55 years have a high prevalence of frailty and a high burden of functional impairment. Optimal management of this population requires close collaboration between infectious diseases specialists and geriatricians.

Executive summary: Prevention and treatment of opportunistic infections and other coinfections in HIV-infected patients: May 2015.

Opportunistic infections continue to be a cause of morbidity and mortality in HIV-infected patients. They often arise because of severe immunosuppression resulting from poor adherence to antiretroviral therapy, failure of antiretroviral therapy, or unawareness of HIV infection by patients whose first clinical manifestation of AIDS is an opportunistic infection. The present article is an executive summary of the document that updates the previous recommendations on the prevention and treatment of opportunistic infections in HIV-infected patients, namely, infections by parasites, fungi, viruses, mycobacteria, and bacteria, as well as imported infections. The article also addresses immune reconstitution inflammatory syndrome. This document is intended for all professionals who work in clinical practice in the field of HIV infection.

Prevention and treatment of opportunistic infections and other coinfections in HIV-infected patients: May 2015.

Despite the huge advance that antiretroviral therapy represents for the prognosis of infection by the human immunodeficiency virus (HIV), opportunistic infections (OIs) continue to be a cause of morbidity and mortality in HIV-infected patients. OIs often arise because of severe immunosuppression resulting from poor adherence to antiretroviral therapy, failure of antiretroviral therapy, or unawareness of HIV infection by patients whose first clinical manifestation of AIDS is an OI. The present article updates our previous guidelines on the prevention and treatment of various OIs in HIV-infected patients, namely, infections by parasites, fungi, viruses, mycobacteria, and bacteria, as well as imported infections. The article also addresses immune reconstitution inflammatory syndrome.

A Phase I Randomized Therapeutic MVA-B Vaccination Improves the Magnitude and Quality of the T Cell Immune Responses in HIV-1-Infected Subjects on HAART.

TRIAL DESIGN: Previous studies suggested that poxvirus-based vaccines might be instrumental in the therapeutic HIV field. A phase I clinical trial was conducted in HIV-1-infected patients on highly active antiretroviral therapy (HAART), with CD4 T cell counts above 450 cells/mm3 and undetectable viremia. Thirty participants were randomized (2:1) to receive either 3 intramuscular injections of MVA-B vaccine (coding for clade B HIV-1 Env, Gag, Pol and Nef antigens) or placebo, followed by interruption of HAART. METHODS: The magnitude, breadth, quality and phenotype of the HIV-1-specific T cell response were assayed by intracellular cytokine staining (ICS) in 22 volunteers pre- and post-vaccination. RESULTS: MVA-B vaccine induced newly detected HIV-1-specific CD4 T cell responses and expanded pre-existing responses (mostly against Gag, Pol and Nef antigens) that were high in magnitude, broadly directed and showed an enhanced polyfunctionality with a T effector memory (TEM) phenotype, while maintaining the magnitude and quality of the pre-existing HIV-1-specific CD8 T cell responses. In addition, vaccination also triggered preferential CD8+ T cell polyfunctional responses to the MVA vector antigens that increase in magnitude after two and three booster doses. CONCLUSION: MVA-B vaccination represents a feasible strategy to improve T cell responses in individuals with pre-existing HIV-1-specific immunity. TRIAL REGISTRATION: ClinicalTrials.gov NCT01571466.

Virological failure to raltegravir in Spain: incidence, prevalence and clinical consequences.

OBJECTIVES: The objective of this study was to evaluate the incidence, prevalence and clinical consequences of virological failure (VF) to raltegravir-based regimens in Spain. METHODS: A multicentre, retrospective, observational study was performed in 10 tertiary hospitals (January 2006 to June 2013). The study included HIV-1-infected patients with loss of virological suppression (LVS; two consecutive HIV-1 RNA ≥50 copies/mL) while receiving raltegravir. VF and low-level viraemia (LLV) were defined as two consecutive HIV-1 RNA ≥200 copies/mL and 50 to <200 copies/mL, respectively. Integrase strand-transfer inhibitor resistance was investigated at LVS. During the 48 weeks following LVS, recorded data included clinical characteristics, treatment discontinuations, AIDS-associated events and deaths. Effectiveness of therapy following LVS was evaluated by ITT and PP. Multivariate regression was used to assess predictors of efficacy. RESULTS: Of the 15 009 HIV-infected patients in participating centres, 2782 (18.5%) had received raltegravir-based regimens. Of those, 192 (6.9%), 125 (4.5%) and 67 (2.4%) experienced LVS, VF and LLV, respectively. The incidence of VF was 1.8 (95% CI, 1.5-2.1) per 100 patients/year. The prevalence of VF was 4.5% (95% CI, 3.8%-5.3%). Integrase-associated mutations were found in 78.8% of patients with integrase genotyping results available. High-level resistance to dolutegravir was not observed. Salvage therapy failed in 34.1% of patients; progression to AIDS/death occurred in 8.3% during the first year following LVS. The latter was associated with intravenous drug use, time on raltegravir and lower CD4+ count nadir in patients who started raltegravir-based treatments as salvage regimens. CONCLUSIONS: VF with raltegravir is infrequent, but often associated with major clinical complications in treatment-experienced patients.

Safety and immunogenicity of a modified vaccinia Ankara-based HIV-1 vaccine (MVA-B) in HIV-1-infected patients alone or in combination with a drug to reactivate latent HIV-1.

OBJECTIVES: The safety, immunogenicity, impact on the latent reservoir and rebound of viral load after therapeutic HIV-1 vaccination with recombinant modified vaccinia Ankara-based (MVA-B) HIV-1 vaccine expressing monomeric gp120 and the fused Gag-Pol-Nef polyprotein of clade B with or without a drug to reactivate latent HIV-1 (disulfiram) were assessed. METHODS: HIV-1-infected patients were randomized to receive three injections of MVA-B (n = 20) or placebo (n = 10). Twelve patients (eight who received vaccine and four who were given placebo) received a fourth dose of MVA-B followed by 3 months of disulfiram. Combined ART (cART) was discontinued 8 weeks after the last dose of MVA-B. Clinical Trials.gov identifier: NCT01571466. RESULTS: MVA-B was safe and well tolerated. A minor, but significant, increase in the T cell responses targeting vaccine inserts of Gag was observed [a median of 290, 403 and 435 spot-forming-cells/10(6) PBMCs at baseline, after two vaccinations and after three vaccinations, respectively; P = 0.02 and P = 0.04]. After interruption of cART, a modest delay in the rebound of the plasma viral load in participants receiving vaccine but not disulfiram was observed compared with placebo recipients (P = 0.01). The dynamics of the viral load rebound did not change in patients receiving MVA-B/disulfiram. No changes in the proviral reservoir were observed after disulfiram treatment. CONCLUSIONS: MVA-B vaccination was a safe strategy to increase Gag-specific T cell responses in chronically HIV-1-infected individuals, but it did not have a major impact on the latent reservoir or the rebound of plasma viral load after interruption of cART when given alone or in combination with disulfiram.

The HIV/AIDS vaccine candidate MVA-B administered as a single immunogen in humans triggers robust, polyfunctional, and selective effector memory T cell responses to HIV-1 antigens.

Attenuated poxvirus vectors expressing human immunodeficiency virus type 1 (HIV-1) antigens are considered promising HIV/AIDS vaccine candidates. Here, we describe the nature of T cell immune responses induced in healthy volunteers participating in a phase I clinical trial in Spain after intramuscular administration of three doses of the recombinant MVA-B-expressing monomeric gp120 and the fused Gag-Pol-Nef (GPN) polyprotein of clade B. The majority (92.3%) of the volunteers immunized had a positive specific T cell response at any time postvaccination as detected by gamma interferon (IFN-γ) intracellular cytokine staining (ICS) assay. The CD4(+) T cell responses were predominantly Env directed, whereas the CD8(+) T cell responses were similarly distributed against Env, Gag, and GPN. The proportion of responders after two doses of MVA-B was similar to that obtained after the third dose of MVA-B vaccination, and the responses were sustained (84.6% at week 48). Vaccine-induced CD8(+) T cells to HIV-1 antigens after 1 year were polyfunctional and distributed mainly within the effector memory (TEM) and terminally differentiated effector memory (TEMRA) T cell populations. Antivector T cell responses were mostly induced by CD8(+) T cells, highly polyfunctional, and of TEMRA phenotype. These findings demonstrate that the poxvirus MVA-B vaccine candidate given alone is highly immunogenic, inducing broad, polyfunctional, and long-lasting CD4 and CD8 T cell responses to HIV-1 antigens, with preference for TEM. Thus, on the basis of the immune profile of MVA-B in humans, this immunogen can be considered a promising HIV/AIDS vaccine candidate.

Resistance and virulence mutations in patients with persistent infection by pandemic 2009 A/H1N1 influenza.

BACKGROUND: Pandemic 2009 influenza A/H1N1 (H1N1v) is resistant to adamantanes, leaving neuraminidase inhibitors as the only therapeutic option. Other mutations are considered to be associated with virulence and clinical severity. However, out of the surveillance programs, few studies analyze the presence of resistance/virulent H1N1v variants in certain clinical circumstances. OBJECTIVES: To define the frequency and role of resistance and virulence mutations in a specific clinical circumstance-in patients with persistent infection by H1N1v. STUDY DESIGN: Observational study of patients with persistent H1N1v infection admitted to our hospital. RESULTS: NAI-resistance mutations were detected in 14.3% of cases with persistent infection (2/14), and in none of the non-persistent controls (0/15). These cases were initially infected with susceptible variants that acquired resistance at different time-points after therapy with oseltamivir (OTV). The first case (case 2) was an HIV-positive patient who rapidly acquired resistance 9 days after diagnosis (6 days on OTV) and whose infection resolved after standard OTV therapy. The second case (case 3) was a patient with chronic lymphocytic leukemia [corrected] and the longest viral persistence (59 days). The resistance mutation was detected in the specimen taken on day 37 after diagnosis (30 days on OTV). Once the resistance mutation was identified, OTV was substituted by zanamivir and the infection resolved. In addition to mutations encoding resistance, variants associated with virulence were also sought. The D225G mutation was not found in any case, whereas the D225E variant was identified in three persistent cases but also in two non-persistent ones. In one patient, the D225E substitution coincided with the H275 resistant mutation. CONCLUSIONS: NAI-resistance mutations were detected, at rather different paces, in non-severe immunosuppressed cases with persistent infection by influenza A/H1N1v.

The eldest of older adults living with HIV: response and adherence to highly active antiretroviral therapy.

OBJECTIVE: The study objective was to analyze the characteristics and the response to therapy in the eldest of the older adults living with human immunodeficiency virus. METHODS: The study included a cohort of patients with human immunodeficiency virus aged 55 years or more on initiating highly active antiretroviral therapy (HAART). Immunologic and virologic response, morbidity, and mortality were assessed. Patients were categorized as aged less than 65 years and 65 years or more. RESULTS: A total of 112 patients were included (82 patients aged<65 years and 30 patients aged> or =65 years). There were no differences between the age groups in baseline characteristics, survival, and virologic response. There was a trend toward better adherence and a lower CD4+ cell increase after HAART in the older group. CONCLUSION: A relationship was found between lower CD4+ cell increase after HAART and advanced age. We found the best adherence to treatment in the eldest of the older adults, and this has been shown to be the only protective independent factor related to virologic failure.

[Tenofovir DF in rescue regimens]. / Tenofovir DF en pautas de rescate.

As with other nucleoside analogues, tenofovir (TDF) can be affected by several mutations in the reverse transcriptase gene. Most nucleoside analogue mutations (NAMs) are not induced specifically by TDF, although they can affect the activity of this drug. The impact of thymidine analogue mutations (TAMs) on tenofovir varies and, as with the remaining nucleoside analogue reverse transcriptase inhibitors, largely depends on the type and number present. Thus, the greater the number of TAMs, and the greater the number of type 1 TAMs, the more TDF activity will be affected. The 41L and 210W mutations have the greatest effect. The incidence of the 65R mutation was slight before the clinical introduction of TDF. This mutation was selected by treatments with zalcitabine monotherapy. However, after TDF came on to the market, the 65R mutation began to be more frequently reported and is currently the signature mutation of this drug. TDF has been shown to be safe and effective in patients with prior virological failure and resistance mutations in the reverse transcriptase gene. In these patients, the presence of the 41L and 210W mutations is associated with a worse response to rescue therapy containing TDF. In contrast, the presence of type 2 TAMs (67N, 70R and 219Q/E/N) has little effect on TDF activity in these patients. Importantly, in TDF therapy, the presence of the 184V mutation is associated with a more favorable virologic response than the absence of this mutation, with any of the distinct combinations of mutations present.

[Microbiological diagnosis of HIV infection]. / Diagnóstico microbiológico de la infección por el VIH.

Currently, there are around 150,000 HIV-infected patients in Spain. This number, together with the fact that this disease is now a chronic condition since the introduction of antiretroviral therapy, has generated an increasing demand on the clinical microbiology laboratories in our hospitals. This increase has occurred not only in the diagnosis and treatment of opportunistic diseases, but also in tests related to the diagnosis and therapeutic management of HIV infection. To meet this demand, the Sociedad de Enfermedades Infecciosas y Microbiología Clinica (Spanish Society of Infectious Diseases and Clinical Microbiology) has updated its standard Procedure for the microbiological diagnosis of HIV infection. The main advances related to serological diagnosis, plasma viral load, and detection of resistance to antiretroviral drugs are reviewed in this version of the Procedure.

Immunotherapy and therapeutic vaccines in HIV infection.

Resistance to medication, adverse effects in the medium-long term, and cost are important limitations to lifelong adherence to highly active antiretroviral therapy (HAART). The combination of HAART with immune therapy to restore and/or boost immune-specific responses to HIV has been proposed, with the ultimate aim of controlling viral replication in the absence of HAART over long periods. The functional defects of the cellular and humoral responses would explain the lack of control of the immune system over viral replication. Different types of immune-mediated therapy have been investigated to solve these problems, including passive immune therapy, cytokines, structured treatment interruptions, immunosuppressors and therapeutic vaccines. Our still limited knowledge of immune mechanisms which can control HIV viral replication and of the causes of the deterioration of cellular and humoral immunity have produced only modest benefits in immune-mediated therapy, and are therefore confined to research for the time being. The availability of an optimal therapeutic vaccine would be an important scientific advance which could be compared with the arrival of protease inhibitors in clinical practice. Therefore, priority should be given to research in this field.