Lucia Taramasso

Epidemiology, species distribution, antifungal susceptibility and outcome of nosocomial candidemia in a tertiary care hospital in Italy.

Candida is an important cause of bloodstream infections (BSI), causing significant mortality and morbidity in health care settings. From January 2008 to December 2010 all consecutive patients who developed candidemia at San Martino University Hospital, Italy were enrolled in the study. A total of 348 episodes of candidaemia were identified during the study period (January 2008–December 2010), with an incidence of 1,73 episodes/1000 admissions. Globally, albicans and non-albicans species caused around 50% of the cases each. Non-albicans included Candida parapsilosis (28.4%), Candida glabrata (9.5%), Candida tropicalis (6.6%), and Candida krusei (2.6%). Out of 324 evaluable patients, 141 (43.5%) died within 30 days from the onset of candidemia. C. parapsilosis candidemia was associated with the lowest mortality rate (36.2%). In contrast, patients with C. krusei BSI had the highest mortality rate (55.5%) in this cohort. Regarding the crude mortality in the different units, patients in Internal Medicine wards had the highest mortality rate (54.1%), followed by patients in ICU and Hemato-Oncology wards (47.6%). This report shows that candidemia is a significant source of morbidity in Italy, with a substantial burden of disease, mortality, and likely high associated costs. Although our high rates of candidemia may be related to high rates of BSI in general in Italian public hospitals, reasons for these high rates are not clear and warrant further study. Determining factors associated with these high rates may lead to identifying measures that can help to prevent disease.

Management of ventilator-associated pneumonia: epidemiology, diagnosis and antimicrobial therapy

Ventilator-associated pneumonia (VAP) is the most frequent infection among patients hospitalized in intensive care units, maintaining a high morbidity and mortality. The global incidence of VAP ranges from 8 to 28%. Early-onset VAP is mainly caused by community pathogens with a favorable pattern of antibiotic sensitivity, whereas late-onset VAP is often caused by multidrug-resistant pathogens, mainly methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter spp. and enteric Gram-negative bacilli. The diagnosis of VAP remains difficult to confirm, lacking both microbiological analysis and radiological signs of high specificity. The Clinical Infection Pulmonary Score has been proposed to overcome the difficulties related to the diagnosis, but is not applicable to all patient categories. A continuous evaluation of the antimicrobial therapeutic options, along with their pharmacodynamic and pharmacokinetic profiles, is mandatory to create therapeutic protocols and reduce VAP-related mortality.

Will new antimicrobials overcome resistance among Gram-negatives?

The spread of resistance among Gram-positive and Gram-negative bacteria represents a growing challenge for the development of new antimicrobials. The pace of antibiotic drug development has slowed during the last decade and, especially for Gram-negatives, clinicians are facing a dramatic shortage in the availability of therapeutic options to face the emergency of the resistance problem throughout the world. In this alarming scenario, although there is a shortage of compounds reaching the market in the near future, antibiotic discovery remains one of the keys to successfully stem and maybe overcome the tide of resistance. Analogs of already known compounds and new agents belonging to completely new classes of antimicrobials are in early stages of development. Novel and promising anti-Gram-negative antimicrobials belong both to old (cephalosporins, carbapenems, β-lactamase inhibitors, monobactams, aminoglycosides, polymyxin analogues and tetracycline) and completely new antibacterial classes (boron-containing antibacterial protein synthesis inhibitors, bis-indoles, outer membrane synthesis inhibitors, antibiotics targeting novel sites of the 50S ribosomal subunit and antimicrobial peptides). However, all of these compounds are still far from being introduced into clinical practice. Therefore, infection control policies and optimization in the use of already existing molecules are still the most effective approaches to reduce the spread of resistance and preserve the activity of antimicrobials.

Effectiveness of a project to prevent HIV vertical transmission in the Republic of Congo

OBJECTIVES To evaluate the effectiveness of a prevention programme against the vertical transmission of HIV in a resource-limited setting and to investigate variables associated with compliance. PATIENTS AND METHODS The Kento-Mwana project (2005-2008) provided counselling, serological and biomolecular testing and prophylaxis/therapy to HIV-positive pregnant women and their children attending four antenatal clinics in Pointe Noire, Republic of Congo. Expected and actual rates of vertical transmission of HIV were compared. Univariate and multivariate analyses were performed in order to identify variables associated with non-compliance. RESULTS The observed transmission rate in the group who completed follow-up was 5/290 (1.7%, 95% CI 0.6%-4.1%). The overall estimated transmission rate in the target population, computed taking into account the expected vertical transmission of HIV among drop-outs, was 67-115/638 (10.5%-18.0%). A comparison between this rate and the expected transmission rate in the absence of intervention (25%-40%) showed that the programme was able to prevent approximately 50% of vertical transmissions. Older age (OR 0.33, 95% CI 0.16-0.66, P = 0.002), telephone availability (OR 0.42, 95% CI 0.24-0.72, P = 0.002) and occupation (OR 0.57, 95% CI 0.29-1.10, P = 0.092) were associated with better compliance. CONCLUSIONS Despite the vast majority of women accepting counselling and testing, many of them refused prophylaxis or dropped out, thus reducing the effectiveness of the intervention from an ideal 2% to a still important but less impressive median transmission rate of 15% (range 10.5%-18%). Promoting participation and compliance, rather than increasing the potency of antiretroviral regimens, is crucial for preventing the vertical transmission of HIV in Africa.

Patient-reported outcomes and low-level residual HIV-RNA in adolescents perinatally infected with HIV-1 after switching to one-pill fixed-dose regimen

The choice of an antiretroviral regimen can often impact on adherence, treatment satisfaction and therefore influence on clinical outcome. These concerns are particularly true in adolescents. In this setting, adherence is usually affected by multifactor events and biopsychosocial factors, which connect and changeover time. We evaluated the effect of a switch to a single-pill fixed-dose regimen on patient-reported outcomes, virologic and immunologic outcomes, and safety in a cohort of adolescents with perinatal HIV-1 infection. In addition, we evaluated the effect on low-level residual HIV-RNA. An open-label, non-randomised study was performed: 12 adolescents with a confirmed viremia <50 copies/mL treated with lamivudine or emtricitabine, tenofovir and efavirenz were switched to one-pill fixed-dose regimen of emtricitabine/tenofovir/efavirenz. At the end of follow-up, the new regimen was associated with improvements in treatment satisfaction, HIV-symptoms, whereas adherence remained high. No immunological or virological significative changes were observed. No side-effects were registered. Moreover, the low-level residual HIV-RNA was <3 copie/mL in all patients. One-pill fixed-dose regimen is an added value that favours adherence, reduces HIV-symptoms, improves patients’ satisfaction and could better control of HIV-RNA in adolescents, too.

Bloodstream infections in HIV-infected patients

ABSTRACT In the combined antiretroviral therapy era, HIV-infected patients remain a vulnerable population for the onset of bloodstream infections (BSI). Worldwide, nontyphoid salmonellae, Streptococcus pneumoniae, Escherichia coli, Staphylococcus aureus and coagulase negative staphylococci are the most important pathogens. Intravenous catheter associated infection, skin-soft tissue infection and endocarditis are associated with Gram-positive bacteremia. Among the Gram-negative, nontyphoidal Salmonella have been previously correlated to sepsis. Other causes of BSI in HIV-infected patients are mycobacteria and fungi. Mycobacteria constitute a major cause of BSI in limited resource countries. Fungal BSI are not frequent and among them Cryptococcus neoformans is the most common life-threatening infection. The degree of immunosuppression remains the key prognostic factor leading to the development of BSI.

Control of the HIV-1 DNA Reservoir Is Associated In Vivo and In Vitro with NKp46/NKp30 (CD335 CD337) Inducibility and Interferon Gamma Production by Transcriptionally Unique NK Cells

ABSTRACT The size of lentiviral DNA reservoirs reflects the effectiveness of immune responses against lentiviruses. So far, abundant information has been gathered on the control of HIV-1 replication. Understanding the innate mechanisms contributing to containment of the HIV DNA reservoir, however, are only partly clarified and are relevant to guiding interventions for reservoir containment or eradication. We studied the contribution of natural killer (NK) cell functional features in HIV patients controlling replication either spontaneously (HIV controllers [HIC]) or after progression and antiretroviral treatment (progressor patients [PP]). An inverse correlation between HIV DNA copy numbers (either total or integrated) in circulating CD4+ cells and NK cell function was observed. Induced interferon gamma (IFN-γ) production and NKp46/NKp30 activating receptor-induced expression correlated inversely with reservoir size. The correlation was present not only for a homogeneous cohort of HIC patients but also when PP were included in the analysis. Adaptive (NKG2C+ CD57+) NK cell features were not associated with reservoir size. However, a distinct set of 370 differentially expressed transcripts was found to underlie functional differences in NK cells controlling HIV DNA reservoir size. In proof-of-principle in vitro experiments of CD4+ cell infection with HIV-1, purified NK cells with the above-mentioned functional/transcriptional features displayed 10- and 30-fold higher abilities to control HIV replication and DNA burdens in vitro, respectively, than those of other NK cells. Thus, NK cells with a specific functional and transcriptional signature contribute to control of the HIV reservoir in CD4+ cells. Their selection, expansion, and/or adoptive transfer may support strategies to eradicate HIV-1 infection or to safely deescalate antiretroviral treatment. IMPORTANCE The most relevant feature of HIV-1 infection is represented by its DNA reservoir size in the body, which guarantees lifelong infection and resumption of virus replication after antiretroviral treatment interruption. So far, there has been little success in the identification of factors contributing to HIV-1 reservoir containment. In this study, by studying quantitative total and integrated HIV-1 DNA levels and NK cells in HIV-1 patients with either progressive or nonprogressive disease, we observed that inducible IFN-γ and natural cytotoxicity receptor (NCR) expression in a specific subset of NK cells with a characteristic transcriptional signature represents a correlate for HIV-1 reservoir control. This represents an advance in our understanding of the mechanism(s) that controls the lentivirus reservoir. Monitoring, selection, expansion, and adoptive transfer of these NK cells may allow monitoring of treatment efficacy and the likelihood of reservoir control and may support protocols for HIV-1 eradication.

Time trend in hypertension prevalence, awareness, treatment, and control in a contemporary cohort of HIV-infected patients: the HIV and Hypertension Study

Background: Hypertension control is often inadequate in HIV patients. In a contemporary, nationwide cohort of Italian HIV-infected adults, we assessed time trends in hypertension prevalence, awareness, treatment, and control. We also evaluated predictors of cardiovascular events and of new-onset hypertension. Methods: Multicenter prospective cohort study, sampling 961 consecutive HIV patients (71% men, mean age 46 ± 9 years, 30% hypertensive) examined in 2010–2014 and after a median follow-up of 3.4 years. Results: Among hypertensive patients, hypertension awareness (63% at baseline and 92% at follow-up), treatment (54 vs. 79%), and control (35 vs. 59%) all improved during follow-up. The incidence of new-onset hypertension was 50.1/1000 person-years (95% confidence interval, 41.2–60.3). Multivariable-adjusted predictors of hypertension were age, BMI, estimated cardiovascular risk, blood pressure, and advanced HIV clinical stage. In total, 35 new cardiovascular events were reported during follow-up (11.1/1000 person-years). In a multivariate model, baseline cardiovascular risk and hypertensive status predicted incident cardiovascular events, whereas a higher CD4+ cell count had a protective role. In treated hypertensive patients, the use of integrase strand transfer inhibitors at follow-up was associated with a lower SBP (average yearly change, −3.8 ± 1.6 vs. −0.9 ± 0.5 mmHg in integrase strand transfer inhibitor users vs. nonusers, respectively, P = 0.02). Conclusion: Hypertension awareness, treatment, and control rates all improved in adult Italian HIV patients over the last few years, although hypertension remains highly prevalent (41%) in middle-aged HIV patients, and significantly impacts cardiovascular morbidity. Traditional risk factors and advanced HIV disease predict new-onset hypertension, whereas CD4+ cell count favorably affects future cardiovascular events.

Case report: management and HBV sequencing in a patient co-infected with HBV and HIV failing tenofovir.

Nucleos(t)ide analogs such as tenofovir, lamivudine, or emtricitabine are active against both HBV and HIV. Tenofovir confers potent and durable HBV‐DNA suppression but the best strategy in case of resistance of HBV to tenofovir remains unknown. A case of a 22‐year‐old patient with co‐infection with HBV and HIV transmitted perinatally is reported. After prolonged and intermittent treatment of HIV with lamivudine and tenofovir, HBV became resistant to lamivudine. Subsequently, clinical resistance to tenofovir occurred, manifesting as HBV‐DNA breakthrough. The non‐compliance was reasonable excluded and HIV‐RNA remained constantly suppressed. Entecavir (1 mg daily) was added and the combination therapy resulted in a rapid and continuous suppression of HBV‐DNA for over 12 months. The treatment was well‐tolerated and safe. No known mutations, such as rtA181T/V associated with rtN236T or A194T that are associated with reduced susceptibility or resistance to tenofovir were detected. However, a unique and complex HBV substitution pattern was found: with a development of rtR192PR mutation at the time of virological failure. Adding entecavir to failing therapy with tenofovir and emtricitabine was feasible, well‐tolerated and resulted in virological success. The rtR192PR, which is located in the B domain near the rtA194T, occurring in a context of a very complex substitutions patterns, might be associated with resistance to tenofovir. J. Med. Virol. 84:1340–1343, 2012.

CD8+CD28−CD127loCD39+ regulatory T-cell expansion: A new possible pathogenic mechanism for HIV infection?

Background: HIV‐associated immunodeficiency is related to loss of CD4+ T cells. This mechanism does not explain certain manifestations of HIV disease, such as immunodeficiency events in patients with greater than 500 CD4+ T cells/&mgr;L. CD8+CD28−CD127loCD39+ T cells are regulatory T (Treg) lymphocytes that are highly concentrated within the tumor microenvironment and never analyzed in the circulation of HIV‐infected patients. Objectives: We sought to analyze the frequency of CD8+CD28−CD127loCD39+ Treg cells in the circulation of HIV‐infected patients. Methods: The frequency of circulating CD8+CD28−CD127loCD39+ Treg cells was analyzed and correlated with viral load and CD4+ T‐cell counts/percentages in 93 HIV‐1–infected patients subdivided as follows: naive (n = 63), elite controllers (n = 19), long‐term nonprogressors (n = 7), and HIV‐infected patients affected by tumor (n = 4). The same analyses were performed in HIV‐negative patients with cancer (n = 53), hepatitis C virus–infected patients (n = 17), and healthy donors (n = 173). Results: HIV‐infected patients had increased circulating levels of functional CD8+CD28−CD127loCD39+ Treg cells. These cells showed antigen specificity against HIV proteins. Their frequency after antiretroviral therapy (ART) correlated with HIV viremia, CD4+ T‐cell counts, and immune activation markers, suggesting their pathogenic involvement in AIDS‐ or non–AIDS‐related complications. Their increase after initiation of ART heralded a lack of virologic or clinical response, and hence their monitoring is clinically relevant. Conclusion: HIV infection induces remarkable expansion of CD8+CD28−CD127loCD39+ Treg cells, the frequency of which correlates with both clinical disease and signs of chronic immune cell activation. Monitoring their frequency in the circulation is a new marker of response to ART when effects on viremia and clinical response are not met.