Growing old with antiretroviral therapy or elderly people in antiretroviral therapy: two different profiles of comorbidity?

BACKGROUND: In persons living with HIV (PLWH), the burden of non-communicable chronic diseases increased over time, because of aging associated with chronic inflammation, systemic immune activation, and long-term exposure to the combination antiretroviral therapy (ART). METHODS: To explore the association of chronological age, age at first ART, and exposure to ART with non-communicable chronic diseases, we performed a cross-sectional analysis to evaluate the prevalence of comorbidities in patients enrolled in the SCOLTA Project, stratified by groups of chronological age (50-59 and 60-69 years) and by years of antiretroviral treatment (ART, ≤ 3 or > 3 years). RESULTS: In 1394 subjects (23.8% women), mean age at enrollment was 57.4 (SD 6.5) years, and at first ART 45.3 (SD 10.7). Men were older than women both at enrollment (57.6 vs 56.8, p = 0.06) and at first ART (45.8 vs 43.6, p = 0.0009). ART duration was longer in women (13.1 vs 11.7 years, p = 0.01). The age- and sex-adjusted rate ratios (aRRs, and 95% confidence interval, CI) showed that longer ART exposure was associated with dyslipidemia (aRR 1.35, 95% CI 1.20-1.52), hypertension (aRR 1.52, 95% CI 1.22-1.89), liver disease (aRR 1.78, 95% CI 1.32-2.41), osteopenia/osteoporosis (aRR 2.88, 95% CI 1.65-5.03) and multimorbidity (aRR 1.36, 95% CI 1.21-1.54). These findings were confirmed in strata of age, adjusting for sex. CONCLUSIONS: Our data suggest that longer ART exposure was associated with increased risk of dyslipidemia, hypertension, and osteopenia/osteoporosis, hence the presence of multimorbidity, possibly due to the exposition to more toxic antiretrovirals. We observed different comorbidities, according to ART exposure and age.

Comparison of Cliff-Lorimer-Based Methods of Scanning Transmission Electron Microscopy (STEM) Quantitative X-Ray Microanalysis for Application to Silicon Oxycarbides Thin Films.

In this work, we compare the results of different Cliff-Lorimer (Cliff & Lorimer 1975) based methods in the case of a quantitative energy dispersive spectrometry investigation of light elements in ternary C-O-Si thin films. To determine the Cliff-Lorimer (C-L) k-factors, we fabricated, by focused ion beam, a standard consisting of a wedge lamella with a truncated tip, composed of two parallel SiO2 and 4H-SiC stripes. In 4H-SiC, it was not possible to obtain reliable k-factors from standard extrapolation methods owing to the strong CK-photon absorption. To overcome this problem, an extrapolation method exploiting the shape of the truncated tip of the lamella is proposed herein. The k-factors thus determined, were then used in an application of the C-L quantification procedure to a defect found at the SiO2/4H-SiC interface in the channel region of a metal-oxide field-effect-transistor device. As in this procedure, the sample thickness is required, a method to determine this quantity from the averaged and normalized scanning transmission electron microscopy intensity is also detailed. Monte Carlo simulations were used to investigate the discrepancy between experimental and theoretical k-factors and to bridge the gap between the k-factor and the Watanabe and Williams ζ-factor methods (Watanabe & Williams, 2006).

Population pharmacokinetics and probability of target attainment of meropenem in critically ill patients.

PURPOSE: Patients admitted to intensive care unit (ICU) with Klebsiella pneumoniae infections are characterized by high mortality. The aims of the present study were to investigate the population pharmacokinetics parameters and to assess the probability of target attainment of meropenem in critically ill patients to provide information for more effective regimens. METHODS: Twenty-seven consecutive patients were included in the study. Meropenem was administered as 3-h intravenous (i.v.) infusions at doses of 1-2 g every 8 or 12 h. Meropenem plasma concentrations were measured by a high-performance liquid chromatography (HPLC) method, and a population pharmacokinetics analysis was performed using NONMEM software. Meropenem plasma disposition was simulated for extended (3 h; 5 h) or continuous i.v. infusions, and the following parameters were calculated: time during which free drug concentrations were above minimum inhibitory concentration (MIC) (fT > MIC), free minimum plasma concentrations above 4× MIC (fCmin > 4× MIC), probability of target attainment (PTA), and cumulative fraction of response (CFR). RESULTS: Gender and severity of sepsis affected meropenem clearance, whose typical population values ranged from 6.22 up to 12.04 L/h (mean ± standard deviation (SD) value, 9.38 ± 4.47 L/h). Mean C min value was 7.90 ± 7.91 mg/L, suggesting a high interindividual variability. The simulation confirmed that 88 and 97.5 % of patients achieved effective C min > 4× MIC values after 3- and 5-h i.v. infusions of meropenem 2 g × 3/day, respectively. On the contrary, the same total daily doses reached the target C min > 4× MIC values in 100 % of patients when administered as continuous i.v. infusions. CONCLUSIONS: Several factors may influence meropenem pharmacokinetics in ICU patients. Continuous i.v. infusions of meropenem seem to be more effective than standard regimens to achieve optimal therapeutic targets.

Genotypic determination of HIV tropism in a cohort of patients perinatally infected with HIV-1 and exposed to antiretroviral therapy.

The aim of this study was to determine the coreceptor tropism by performing genotypic HIV-1 tropism testing in a cohort of patients perinatally infected with HIV-1 and exposed to antiretroviral therapy. Genotypic coreceptor tropism was determined in patients with HIV-1 RNA<100 copies/mL using PBMC samples by gp120 V3 sequencing followed by geno2pheno interpretation (set at a false positive rate [FPR] of 20%) and in patients with ≯100 copies/mL using plasma samples (set at a FPR of 20%), according to European guidelines. Out of 55 patients, 50 had an HIV-1 subtype B strain, and mean (SD) age was 18.2 (4.6) years. The median duration of antiretroviral therapy was 13 years (range, 3-23). Thirty-three (60%) patients harbored the R5 virus. At the time of the testing, the median CD4+ T lymphocyte cell count and percentage were 705 cells/mm3 (474-905) and 32.5% in group R5 and 626 cells/mm3 (450-755) and 31.7% in group X4/D-M, respectively. The nadir of CD4+ T-cell count in groups R5 and X4/D-M were 322 cells/mm3 (230-427) and 340 cells/mm3 (242-356), respectively. These differences were not statistically significant. Fifteen patients had HIV-1 RNA ≯50 copies/mL. The median HIV-1 RNA and HIV-1 DNA were comparable in both groups without a statistical difference. The study provides an overview of the prevalence of coreceptor tropism in a cohort of patients who were vertically infected with HIV-1. The high prevalence of X4/D-M-tropic strains may simply reflect the long-term exposure to HIV.

Innovative Approaches to Monitor Central Line Associated Bloodstream Infections (CLABSIs) Bundle Efficacy in Intensive Care Unit (ICU): Role of Device Standardized Infection Rate (dSIR) and Standardized Utilization Ratio (SUR)-An Italian Experience.

In several settings, the COVID-19 pandemic determined a negative impact on the occurrence of healthcare-associated infection, particularly for on central lines associated bloodstream infections (CLABSI). In our setting, we observed a significant increase in CLABSI in our intensive care unit (ICU) during 2020 and 2021 vs. 2018 to 2019. A refresher training activity on central venous catheter (CVC) management bundles was carried out in September-October 2021 for the ICU health staff. We assessed the impact of bundle implementation by means of standardized indicators, such as the Device Utilization Ratio (DUR), in this case, the Central Line Utilization Ratio, the Standardized Utilization Ratio (SUR), and the device Standardized Infection Ratio (dSIR). Standardized ratios for device use and infection ratio were computed using data from 2018 and 2019 as expectation data. After bundle implementation, we observed a significant reduction of dSIR (p < 0.001), which dropped from 3.23 and 2.99 in the 2020-2021 biennium to 1.11 in 2022 (CLABSI in the first quarter only); no more CLABSI were observed afterwards. Standardized ratios proved helpful in identify increasing trends of CLABSI in the ICU and monitoring the impact of a simple effective tool, i.e., training on and implementation of a bundle for CVC management.

Inflammation markers correlate with common carotid intima-media thickness in patients perinatally infected with human immunodeficiency virus 1.

OBJECTIVES: To investigate common carotid intima-media thickness in a cohort of patients who were vertically infected with human immunodeficiency virus 1 (HIV-1). METHODS: We conducted a cross-sectional observational study. Human immunodeficiency virus 1-infected patients were compared with age-, sex-, and body mass index-matched healthy participants. Common carotid intima-media thickness was measured in all participants on both sides of the neck, and the mean intima-media thickness was calculated. Metabolic parameters and markers of inflammation were measured only in HIV-1-infected patients. Statistical analysis was performed by multiple regression and by a matrix of Pearson correlation coefficients. The Student t test was used to compare mean common carotid intima-media thickness values between groups. RESULTS: Forty patients (21 female) with HIV-1 infection acquired from birth with a mean age ± SD of 16.3 ± 4.7 years and 27 healthy participants (11 female) with a mean age of 17.7 ± 4.6 years were included in the study. Mean common carotid intima-media thickness in the HIV-1-infected group (0.450 ± 0.088 mm) was significantly higher (P < .05) than in the control group (0.407 ± 0.079 mm). No significant association was found between intima-media thickness and a specific antiretroviral regimen, exposure to combined antiretroviral agents, and HIV status. In multiple regression analyses, higher levels of insulin (P= .007) and elevated levels of glycated hemoglobin (P= .01) were associated with intima-media thickness changes. CONCLUSIONS: Patients perinatally infected with HIV have increased common carotid intima-media thickness compared with healthy individuals. These changes were more pronounced with increasing age and inflammation markers. Interventions that improve cardiovascular risk profiles should be considered in HIV-infected young adults.

The use of continuous positive airway pressure during the second and third waves of the COVID-19 pandemic.

Background: In a preliminary study during the first COVID-19 pandemic wave, we reported a high rate of success with continuous positive airway pressure (CPAP) in preventing death and invasive mechanical ventilation (IMV). That study, however, was too small to identify risk factors for mortality, barotrauma and impact on subsequent IMV. Thus, we re-evaluated the efficacy of the same CPAP protocol in a larger series of patients during second and third pandemic waves. Methods: 281 COVID-19 patients with moderate-to-severe acute hypoxaemic respiratory failure (158 full-code and 123 do-not-intubate (DNI)), were managed with high-flow CPAP early in their hospitalisation. IMV was considered after 4 days of unsuccessful CPAP. Results: The overall recovery rate from respiratory failure was 50% in the DNI and 89% in the full-code group. Among the latter, 71% recovered with CPAP-only, 3% died under CPAP and 26% were intubated after a median CPAP time of 7 days (IQR: 5-12 days). Of the patients who were intubated, 68% recovered and were discharged from the hospital within 28 days. Barotrauma occurred during CPAP in <4% of patients. Age (OR 1.128; p <0.001) and tomographic severity score (OR 1.139; p=0.006) were the only independent predictors of mortality. Conclusions: Early treatment with CPAP is a safe option for patients with acute hypoxaemic respiratory failure due to COVID-19.

Impact of the COVID-19 Pandemic on Epidemiology of Antibiotic Resistance in an Intensive Care Unit (ICU): The Experience of a North-West Italian Center.

The SARS-CoV-2 pandemic caused an increase in intensive care unit (ICU) hospitalizations with a rise in morbidity and mortality; nevertheless, there is still little evidence on the impact of the pandemic on antibiotic resistance in ICUs. This is a retrospective, monocentric epidemiological study. The aim of the study was to describe and analyze the impact of the SARS-CoV-2 pandemic on ICU bacterial resistance patterns. All bacteria isolated from all patients admitted to the E.O. Galliera ICU from January 2018 to December 2022 were included. Antibiotic resistance (AR) profiles were evaluated. A total of 1021 microorganisms were identified, of which 221 (12.47%) had a resistance pattern (resistant organisms; ROs). In this time, there were 1679 patients with a total of 12,030 hospitalization days. The majority of microorganisms were Gram-negative (79.66% in 2018, 77.29% in 2019, 61.83% in 2020, 62.56% in 2021, and 60.75% in 2022), but an increase in Gram-positive microorganisms was observed (20.34 to 39.25% between 2018 and 2022). The prevalence of AR was 19.44% in 2018, 11.54% in 2019, 38.04% in 2020, 34.15% in 2021, and 39.29% in 2022 for Gram-positive microorganisms and 19.86% in 2018, 13.56% in 2019, 18.12% in 2020, 12.41% in 2021, and 12.31% in 2012 for Gram-negative microorganisms. The incidence of ROs showed a COVID-19-related increase in 2020-2021, followed by a lowering trend since 2021, and a new increase in 2022. Possible explanations are antibiotic overtreatment and a decrease in containment measures. An interesting finding was the cumulative lowering trend of carbapenem-resistant K. pneumoniae and P. aeruginosa, probably due to different patient features.

Lipids and Transaminase in Antiretroviral-Treatment-Experienced People Living with HIV, Switching to a Doravirine-Based vs. a Rilpivirine-Based Regimen: Data from a Real-Life Setting.

Doravirine (DOR) is a newly approved non-nucleoside reverse transcriptase inhibitor (NNRTI). We aimed to investigate, in a real-life setting, how switching to a DOR-based regimen rather than a rilpivirine (RPV)-based regimen impacted metabolic and hepatic safety. The analysis included 551 antiretroviral treatment (ART)-experienced people living with HIV (PLWH), starting RPV-based or DOR-based regimens with viral load < 200 copies/mL, baseline (T0), and at least one control visit (6-month visit, T1). We enrolled 295 PLWH in the RPV and 256 in the DOR cohort. At T1, total cholesterol (TC), low-density lipoprotein-C (LDL-C), and triglycerides significantly decreased in both DOR and RPV cohorts, while high-density lipoprotein-C (HDL-C) only decreased in RPV-treated people. Consistently, the TC/HDL-C ratio declined more markedly in the DOR (-0.36, p < 0.0001) than in the RPV cohort (-0.08, p = 0.25) (comparison p = 0.39). Similar trends were observed when excluding the PLWH on lipid-lowering treatment from the analysis. People with normal alanine aminotransferase (ALT) levels showed a slight ALT increase in both cohorts, and those with baseline ALT > 40 IU/L experienced a significant decline (-14 IU/L, p = 0.008) only in the DOR cohort. Lipid profile improved in both cohorts, and there was a significant reduction in ALT in PLWH with higher-than-normal baseline levels on DOR-based ART.

Identifying patients harboring extended-spectrum-beta-lactamase-producing Enterobacteriaceae on hospital admission: derivation and validation of a scoring system.

Increases in community-acquired infections caused by extended-spectrum-ß-lactamase (ESBL)-producing Enterobacteriaceae have important implications for hospital infection control and empirical antibiotic therapy protocols. We developed and validated a tool for identifying patients harboring these organisms at hospital admission. We retrospectively analyzed chart data for 849 adult inpatients. The derivation cohort included 339 patients admitted to a large hospital in Rome during 2008, with (n = 113) or without (n = 226) culture positivity for ESBL-producing Escherichia coli, Klebsiella spp., or Proteus mirabilis within 48 h after admission. Logistic-regression-based prediction scores were calculated based on variables independently associated with the outcome. The model was validated in a second cohort (n = 510) selected with identical criteria in hospitals in Genoa and Turin during 2009. Prediction scores were based on the following six variables (reported with odds ratio for study outcome and the 95% confidence intervals in brackets): recent (≤ 12 months before admission) hospitalization (5.69 [2.94 to 10.99]), transfer from another health care facility (5.61 [1.65 to 19.08]), Charlson comorbidity score ≥ 4 (3.80 [1.90 to 7.59]), recent (≤ 3 months before admission) ß-lactam and/or fluoroquinolone treatment (3.68 [1.96 to 6.91]), recent urinary catheterization (3.52 [1.96 to 6.91]), and age ≥ 70 years (3.20 [1.79 to 5.70]). The model displayed good calibration and good-to-excellent discrimination in the derivation and validation sets (Hosmer-Lemshow χ(2) = 15.28 and 14.07; P = 0.17 and 0.23; areas under the receiver-operating characteristic curve, 0.83 and 0.92). It reliably identified patients likely to be harboring ESBL-producing Enterobacteriaceae at hospital admission who may need special infection control measures. Further study is needed to confirm this model's potential as a guide for prescribing empirical antibiotic therapy.

Riding the COVID Waves: Clinical Trends, Outcomes, and Remaining Pitfalls of the SARS-CoV-2 Pandemic: An Analysis of Two High-Incidence Periods at a Hospital in Northern Italy.

BACKGROUND: Italy was the first western country to face an uncontrolled outbreak of SARS-CoV-2 infection. The epidemic began in March 2020 within a context characterised by a general lack of knowledge about the disease. The first scientific evidence emerged months later, leading to treatment changes. The aim of our study was to evaluate the effects of these changes. METHODS: Data from a hospital in Genoa, Italy, were analysed. Patients deceased from SARS-CoV-2 infection were selected. Data were compared by dividing patients into two cohorts: "phase A" (March-May 2020) and "phase B" (October-December 2020). RESULTS: A total of 5142 patients were admitted. There were 274 SARS-CoV-2-related deaths (162 phase A and 112 phase B). No differences were observed in terms of demographics, presentation, or comorbidities. A significant increase was recorded in corticosteroid use. Mortality was 33.36% during phase A, falling to 21.71% during phase B. When subdividing the trend during the two phases by age, we found a difference in people aged 65-74 years. CONCLUSIONS: There is scarce evidence regarding treatment for SARS-CoV-2 (especially for severe infection). However, treatment changes improved the prognosis for people under the age of 75. The prognosis for older people remains poor, despite the improvements achieved.

Use of colistin in adult patients: A cross-sectional study.

OBJECTIVES: The aim of this study was to assess colistin use in a country endemic for multidrug-resistant Gram-negative bacteria (MDR-GNB). METHODS: Colistin prescription patterns were evaluated in 22 Italian centres. Factors associated with use of colistin in combination with other anti-MDR-GNB agents were also assessed. RESULTS: A total of 221 adults receiving colistin were included in the study. Their median age was 64 years (interquartile range 52-73 years) and 134 (61%) were male. Colistin was mostly administered intravenously (203/221; 92%) and mainly for targeted therapy (168/221; 76%). The most frequent indications for colistin therapy were bloodstream infection and lower respiratory tract infection. Intravenous colistin was administered in combination with at least another anti-MDR-GNB agent in 80% of cases (163/203). A loading dose of 9 MU of colistimethate was administered in 79% of patients receiving i.v. colistin and adequate maintenance doses in 85%. In multivariable analysis, empirical therapy [odds ratio (OR) = 3.25, 95% confidence interval (CI) 1.24-8.53;P = 0.017] and targeted therapy for carbapenem-resistant Enterobacterales infection (OR = 4.76, 95% CI 1.69-13.43; P = 0.003) were associated with use of colistin in combination with other agents, whilst chronic renal failure (OR = 0.39, 95% CI 0.17-0.88; P = 0.024) was associated with use of colistin monotherapy. CONCLUSION: Colistin remains an important option for severe MDR-GNB infections when other treatments are not available. Despite inherent difficulties in optimising its use owing to peculiar pharmacokinetic/pharmacodynamic characteristics, colistin was mostly used appropriately in a country endemic for MDR-GNB.

Size effect on high temperature variable range hopping in Al+ implanted 4H-SiC.

The hole transport properties of heavily doped 4H-SiC (Al) layers with Al implanted concentrations of 3 × 1020 and 5 × 1020 cm-3 and annealed in the temperature range 1950-2100 °C, have been analyzed to determine the main transport mechanisms. This study shows that the temperature dependence of the resistivity (conductivity) may be accounted for by a variable range hopping (VRH) transport into an impurity band. Depending on the concentration of the implanted impurities and the post-implantation annealing treatment, this VRH mechanism persists over different temperature ranges that may extend up to room temperature. In this framework, two different transport regimes are identified, having the characteristic of an isotropic 3D VRH and an anisotropic nearly 2D VRH. The latter conduction mechanism appears to take place in a rather thick layer (about 400 nm) that is too large to induce a confinement effect of the carrier hops. The possibility that an anisotropic transport may be induced by a structural modification of the implanted layer because of a high density of basal plane stacking faults (SF) in the implanted layers is considered. The interpretation of the conduction in the heaviest doped samples in terms of nearly 2D VRH is supported by the results of the transmission electron microscopy (TEM) investigation on one of the 5 × 1020 cm-3 Al implanted samples of this study. In this context, the average separation between basal plane SFs, measured along the c-axis, which is orthogonal to the carrier transport during electrical characterization, appears to be in keeping with the estimated value of the optimal hopping length of the VRH theory. Conversely, no SFs are detected by TEM in a sample with an Al concentration of 1 × 1019 cm-3 where a 3D nearest neighbor hopping (NNH) transport is observed.

Meropenem for treating KPC-producing Klebsiella pneumoniae bloodstream infections: Should we get to the PK/PD root of the paradox?

The objective of this study was to assess the achievement of pharmacokinetic/pharmacodynamic (PK/PD) targets of meropenem (MEM) in critically-ill patients with bloodstream infections (BSI) due to Klebsiella pneumoniae-carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) with MEM minimum inhibitory concentrations (MICs) ≥16 mg/L. Nineteen critically-ill patients with KPC-Kp BSI were given combination therapy including MEM, tigecycline, plus colistin or gentamicin (according to susceptibility testing). MEM was administered as an extended 3-hour infusion of 2 g every 8 hours, or adjusted according to renal function. MEM plasma concentrations were determined by high-performance liquid chromatography. PK/PD targets for MEM were defined as T > 40% 1×MIC and T > 40% 4×MIC. Possible synergisms between MEM and coadministered agents were assessed by time-kill assays based on plasma levels for MEM and on fixed plasma concentrations for the other agents. In none of 19 patients MEM reached any PK/PD target. The actual MEM MICs were 256, 512, and 1024 mg/L in 1, 3, and 15 isolates, respectively. However, theoretically, the PK/PD target of T > 40% 1×MIC could have been achieved in 95%, 68%, 32% and 0% of the isolates for MIC equal to 8, 16, 32, and 64 mg/L, respectively. No synergisms were observed between MEM and coadministered agents. In conclusion, high-dose MEM failed to reach PK/PD targets in 19 patients with BSI due to KPC-Kp with very high MEM MICs. On a theoretical basis, our results suggest a possible usefulness of MEM against resistant blood isolates with MICs up to 32 mg/L.

Dual emission in asymmetric "giant" PbS/CdS/CdS core/shell/shell quantum dots.

Semiconducting nanocrystals optically active in the infrared region of the electromagnetic spectrum enable exciting avenues in fundamental research and novel applications compatible with the infrared transparency windows of biosystems such as chemical and biological optical sensing, including nanoscale thermometry. In this context, quantum dots (QDs) with double color emission may represent ultra-accurate and self-calibrating nanosystems. We present the synthesis of giant core/shell/shell asymmetric QDs having a PbS/CdS zinc blende (Zb)/CdS wurtzite (Wz) structure with double color emission close to the near-infrared (NIR) region. We show that the double emission depends on the excitation condition and analyze the electron-hole distribution responsible for the independent and simultaneous radiative exciton recombination in the PbS core and in the CdS Wz shell, respectively. These results highlight the importance of the driving force leading to preferential crystal growth in asymmetric QDs, and provide a pathway for the rational control of the synthesis of double color emitting giant QDs, leading to the effective exploitation of visible/NIR transparency windows.

Simplification to monotherapy with lopinavir/ritonavir in adolescents with vertically acquired HIV-1 infection.

In recent years, the use of boosted protease inhibitors monotherapy has become increasingly important, especially considering the advantages in terms of costs, tolerability, and simplification. Despite that, knowledge about the efficacy and safety of this approach in HIV-1-infected adolescents who have acquired HIV-1 infection through perinatal transmission is still limited. We report here our experience with two adolescents who have been successfully treated with lopinavir/ritonavir monotherapy.