Plasma, Intracellular and Lymph node Antiretroviral Concentrations and HIV DNA Change During Primary HIV Infection: Results from the INACTION P25 Study.

Despite its high effectiveness, combination antiretroviral treatment (cART) has a limited effect on HIV-DNA reservoir, which establishes early during primary infection (PHI) and is maintained by latency, homeostatic T-cells proliferation, and residual replication: this can be associated with low drug exposure in lymphoid tissues and/or suboptimal adherence to antiretroviral drugs (ARVs). Aim of this study was to assess ARVs concentrations in plasma, peripheral blood mononuclear cells (PBMC) and lymph nodes (LN), and their association to HIV-RNA and DNA decay during PHI. Participants were randomized to receive standard doses of darunavir/cobicistat (arm I), dolutegravir (arm II) or both (arm III), with a backbone of tenofovir alafenamide and emtricitabine. Total HIV-DNA was measured by digital-droplet PCR in PBMC at baseline, 12 and 48 weeks. Plasma and PBMC drugs concentrations were determined at 2, 12 and 48 weeks (LN at 12 weeks) by UHPLC-MS/MS. Seventy-two participants were enrolled, mostly male (n=68), median age 34 years and variable Fiebig stages (V-VI 57.7%, I-II 23.9%, and III-IV 18.3%). Twenty-six patients were assigned to Arm I, 27 to Arm II and 19 to Arm III. After 48 weeks, most patients had undetectable viremia, with minor between-arms differences in HIV-RNA decay. Patients with Fiebig I-II showed faster HIV-RNA and HIV-DNA decay. Intracellular-tissue penetration was high for nucleoside analogues and low-moderate for darunavir and dolutegravir. Only tenofovir diphosphate concentrations in PBMC showed correlation with HIV-DNA decay. Overall, this study suggests the timing of treatment initiation and intracellular tenofovir penetration as primary and secondary factors affecting HIV reservoir.

Association between tight junction proteins and cognitive performance in untreated Persons living with HIV (PLWH).

BACKGROUND: HIV-associated neurocognitive disorders (HAND) still affects persons living with HIV (PLWH) and their pathogenesis isn't completely understood. We aimed to explore the association between plasma and CSF markers of blood-brain barrier (BBB) impairment and HAND in untreated PLWH. DESIGN: Cross-sectional study. METHODS: We enrolled untreated PLWH, who underwent blood exams and lumbar puncture to measure inflammation (IL-15, TNF-α), BBB damage (zonulin and tight junction proteins, TJs: occludin, claudin-5) and endothelial adhesion molecules (VCAM-1, ICAM-1). A comprehensive neurocognitive battery was used to diagnose HAND (Frascati criteria). RESULTS: Twenty-one patients (21/78, 26,9%) patients presented HAND (100% ANI). HAND patients displayed more frequently non-CNS AIDS-defining conditions, lower nadir CD4+ T-cells and increased CD4+ T-cell exhaustion (lower CD4+CD127+ and CD4+CD45RA+ T cells percentages), in comparison to subjects without cognitive impairment. Furthermore, HAND was characterized by higher plasma inflammation (IL-15), but lower CSF levels of biomarkers of BBB impairment (zonulin and occludin). The association between BBB damage with HAND was confirmed by fitting a multivariable logistic regression. CSF/plasma endothelial adhesion molecules weren't associated with HAND, but with a poor performance in different cognitive domains. CONCLUSIONS: By showing heightened inflammation and BBB impairment, our study suggests loss of BBB integrity as a possible factor contributing to the development of HAND in untreated PLWH.

Host single nucleotide polymorphisms and biomarkers of neuronal damage and inflammation in people living with HIV.

OBJECTIVES: Blood-brain barrier impairment is frequent in people living with human immunodeficiency virus (PLWHIV), affecting the penetration of target cells and antiretrovirals into the central nervous system, through transporters (e.g. ABCB1), leading to neuroinflammation. This study aimed to identify variants of genes encoding transporters able to predict neuroinflammation biomarker levels. METHODS: Cerebrospinal fluid (CSF) and plasma samples were obtained from PLWHIV. The CSF biomarkers were quantified by commercial assays. Genetic variants were evaluated through real-time polymerase chain reaction (PCR). RESULTS: A total of 107 PLWHIV (163 samples) were included in the study: 79% were male, median age was 48.5 years, CD4% was 25%, and HIV-associated neurocognitive disorder (HAND) was observed in 17.8%. The ABCB1 2677G>T genetic variant showed a different allelic distribution according to the clinical group (P = 0.026). In linear regression analyses, HIV-related central nervous system disorders, ABCG2 1194+928CC genotype, log viral load, CSF-to-serum albumin ratio, ß-1,42 levels, and CSF proteins were retained in the final model as factors independently associated with CSF neopterin levels; CSF proteins and integrase inhibitor use were associated with CSF tau level in the multivariate model. Phospho-tau regression analysis reported the ABCB1 2677GT/TT genotype and CSF proteins as predictors in the final model; sex, protease inhibitors, neopterin, and ABCB1 2677 GT/ TT genotype were predictors in the multivariate regression for ß-1,42. CONCLUSIONS: For the first time, pharmacogenetic and clinical features were found to be predictors of neuro-inflammation biomarkers.

Knowledge of Sexually Transmitted Infections and HIV among People Living with HIV: Should We Be Concerned?

Poor knowledge of sexually transmitted infections (STIs) and HIV among people with HIV (PLHIV) could worsen life quality. We aimed to investigate their STI and HIV knowledge, disclosure and undetectable = untransmittable (U=U). We proposed an anonymous questionnaire regarding STI and HIV to PLHIV attending ten Italian outpatient infectious diseases clinics. Moreover, disclosure and U=U were investigated. The calculated sample size was 178 people. Considering a missing response of 10%, the final sample size was 196. We enrolled 200 PLHIV (73.5% males), with a median age of 52.5 (IQR 41-59) years. The mean score was 7.61 ± 1.22 with no difference by gender, education, and employment. Significant statistical difference was observed by sexual orientation; bisexuals and those who preferred not to answer had a lower score than heterosexuals and MSM (p = 0.0032). PLHIV showed poor knowledge about HIV transmission (25% appropriately answered). Nearly 30% responded that virologically suppressed PLHIV could transmit the infection. Finally, 137 (68.5%) and 158 (79.0%) disclosed to the general practitioner and family and friends, respectively. Nearly 52.0% knew the meaning of U=U, and 83.6% highlighted its positive rebound. In conclusion, important knowledge gaps are present among PLHIV regarding U=U, and its implications are little-known. Improving PLHIVs' awareness will undermine self-stigma and enhance life quality.

Outcomes of Drug Interactions Between Antiretrovirals and Co-Medications, Including Over-the-Counter Drugs: A Real-World Study.

INTRODUCTION: The objective was to characterize real-world outcomes of drug-drug interactions (DDIs) between antiretrovirals (ARVs) and other drugs, including over-the-counter medications (OTC), and treatment outcomes in clinical practice. METHODS: www.clinicalcasesDDIs.com is an open-access website for healthcare providers to consult and briefly describe real-world clinical cases on DDI with ARVs. We reviewed all the clinical cases reported to the website between March 2019 and May 2023. RESULTS: A total of 139 cases were reported, mostly involving ritonavir or cobicistat (boosters; 74 cases), unboosted integrase inhibitors (InSTI; 29 cases), and non-nucleoside reverse transcriptase inhibitors (NNRTI; 23 cases). Central nervous system drugs (29 cases) and cardiovascular drugs (19 cases) were the most frequently described co-medications. Notably, OTC medications were implicated in 27 cases, including mineral supplements (11 cases), herbals (8 cases), weight loss drugs (4 cases), anabolic steroids (3 cases), and recreational drugs (1 case). OTC acted as the perpetrator drug in 21 cases, leading to loss of ARV efficacy in 17 instances (mineral supplements in 10 cases, weight loss drugs in 4 cases, herbals in 3 cases). Additionally, toxicity was reported in 4 out of 6 cases where OTC was considered the victim drug of the DDI (anabolic steroids in 3 cases, MDMA in 1 case). CONCLUSIONS: Frequent unwanted outcomes resulting from DDIs between ARVs and OTC medications underscore the importance of integrating non-prescription drugs into medication reconciliation. The real-world data available through www.clinicalcasesDDIs.com serves as a valuable resource for assessing the clinical relevance of DDIs.

Mycobacterium avium complex pulmonary disease patients with limited treatment options.

How to identify MAC-PD patients with limited treatment options: an expert consensus https://bit.ly/3QwLQ8T.

Primary HIV infection features colonic damage and neutrophil inflammation yet containment of microbial translocation.

INTRODUCTION: Impairment of the gastrointestinal barrier leads to microbial translocation and peripheral immune activation, which are linked to disease progression. Data in the setting of primary HIV/SIV infection suggest that gut barrier damage is one of the first events of the pathogenic cascade, preceding mucosal immune dysfunction and microbial translocation. We assessed gut structure and immunity as well as microbial translocation in acutely and chronically-infected, combination antiretroviral therapy (cART)-naive individuals. METHODS: Fifteen people with primary HIV infection (P-HIV) and 13 with chronic HIV infection (C-HIV) c-ART-naive participants were cross-sectionally studied. Gut biopsies were analysed in terms of gut reservoirs (total, integrated and unintegrated HIV DNA); tight junction proteins (E-cadherin, Zonula Occludens-1), CD4 + expression, neutrophil myeloperoxidase (histochemical staining); collagen deposition (Masson staining). Flow cytometry was used to assess γδ T-cell frequency (CD3 + panγδ+Vδ1+/Vδ2+). In plasma, we measured microbial translocation (LPS, sCD14, EndoCAb) and gut barrier function (I-FABP) markers (ELISA). RESULTS: P-HIV displayed significantly higher tissue HIV DNA, yet neutrophil infiltration and collagen deposition in the gut were similar in the two groups. In contrast, microbial translocation markers were significantly lower in P-HIV compared with C-HIV. A trend to higher mucosal E-cadherin, and gut γδ T-cells was also observed in P-HIV. CONCLUSION: Early HIV infection features higher HIV DNA in the gut, yet comparable mucosal alterations to those observed in chronic infection. In contrast, microbial translocation is contained in primary HIV infection, likely because of a partial preservation of E-cadherin and mucosal immune subsets, namely γδ T-cells.

Intrathecal production of anti-Epstein-Barr virus viral capsid antigen IgG is associated with neurocognition and tau proteins in people with HIV.

OBJECTIVE: HIV and Epstein-Barr virus (EBV) co-infection has been linked to increased immune activation and larger HIV reservoir. We assessed whether anti-EBV humoral responses are associated with increased cerebrospinal fluid (CSF) inflammation and with neurocognitive impairment (NCI) in people with HIV (PWH). DESIGN: Cross-sectional analysis in 123 EBV-seropositive PWH either on antiretroviral therapy ( n  = 70) or not. METHODS: Serum and CSF anti-EBV viral capsid antigen immunoglobulin G (anti-EVI) and CSF EBV DNA were measured by commercial immunoassay and RT-PCR. Seventy-eight participants without neurological confounding factors underwent neurocognitive assessment (Global Deficit Score, GDS). CSF total tau and 181-phosphorylated-tau (ptau) were measured by immunoassays together with biomarkers of blood-brain barrier (BBB) integrity, immune activation, astrocytosis, and intrathecal synthesis. Logistic and linear regressions and moderation analysis were used to investigate the relationships between CSF anti-EVI, GDS, and biomarkers. RESULTS: Twenty-one (17.1%) and 22 participants (17.9%) had detectable CSF anti-EVI (10.5-416.0 U/ml) and CSF EBV DNA (25-971 copies/ml). After adjusting for BBB integrity, age, and clinical factors, the presence of CSF anti-EVI was only associated with serum levels of anti-EVI, and not with CSF EBV DNA. CSF anti-EVI, tau and ptau showed reciprocal interactions affecting their associations with GDS. After adjusting for demographics and clinical parameters, higher CSF anti-EVI levels were associated with worse GDS (aß 0.45, P  < 0.001), and CSF levels of tau and ptau had a moderation effect on the strength of this association (models' P  < 0.001). CONCLUSION: Humoral immune responses against EBV within the central nervous system may contribute to NCI in PWH through mechanisms that involve neuronal injury.

Influence of efavirenz and 8-hydroxy-efavirenz plasma levels on cognition and central nervous system side effects.

OBJECTIVES: To investigate whether efavirenz (EFV) or 8-hydroxy-EFV (8-OH-EFV) plasma levels are associated with neurocognitive impairment and central nervous system (CNS) side effects. METHODS: We conducted a cross-sectional analysis to explore the potential links between EFV/8-OH-EFV levels and cognitive performance or CNS-related side effects in patients screened within a randomized trial involving a switch from EFV to rilpivirine. The Mann-Whitney test was employed to compare drug levels in patients with or without cognitive impairment, depression, anxiety, sleep disorder or CNS symptoms. Additionally, Spearman's test was used to assess correlations between drug levels and test scores. RESULTS: Among 104 patients, neither EFV nor 8-OH-EFV levels were linked to cognitive impairment, although trends towards higher EFV levels were observed in those with impaired executive function (p = 0.055) and language performances (p = 0.021). On the other hand, elevated 8-OH-EFV levels, but not EFV levels, were associated with more CNS side effects (222 vs. 151 ng/mL, p = 0.027), depressive symptoms (247 vs. 164 ng/mL, p = 0.067) and sleep impairment (247 vs. 164 ng/mL, p = 0.078). Consistently, a trend towards a correlation between EFV levels and lower z-scores in executive function and motor function was observed, while 8-OH-EFV levels, but not EFV levels, were directly correlated with symptom scores. CONCLUSIONS: Higher levels of 8-OH-EFV were associated with CNS side effects, while EFV levels were only marginally associated with cognitive performance, thus suggesting that EFV and its metabolite may act differently in determining detrimental neurological effects.

Parietal resting-state EEG alpha source connectivity is associated with subcortical white matter lesions in HIV-positive people.

OBJECTIVE: Parietal resting-state electroencephalographic (rsEEG) alpha (8-10 Hz) source connectivity is abnormal in HIV-positive persons. Here we tested whether this abnormality may be associated with subcortical white matter vascular lesions in the cerebral hemispheres. METHODS: Clinical, rsEEG, and magnetic resonance imaging (MRI) datasets in 38 HIV-positive persons and clinical and rsEEG datasets in 13 healthy controls were analyzed. Radiologists visually evaluated the subcortical white matter hyperintensities from T2-weighted FLAIR MRIs (i.e., Fazekas scale). In parallel, neurophysiologists estimated the eLORETA rsEEG source lagged linear connectivity from parietal cortical regions of interest. RESULTS: Compared to the HIV participants with no/negligible subcortical white matter hyperintensities, the HIV participants with mild/moderate subcortical white matter hyperintensities showed lower parietal interhemispheric rsEEG alpha lagged linear connectivity. This effect was also observed in HIV-positive persons with unimpaired cognition. This rsEEG marker allowed good discrimination (area under the receiver operating characteristic curve > 0.80) between the HIV-positive individuals with different amounts of subcortical white matter hyperintensities. CONCLUSIONS: The parietal rsEEG alpha source connectivity is associated with subcortical white matter vascular lesions in HIV-positive persons, even without neurocognitive disorders. SIGNIFICANCE: Those MRI-rsEEG markers may be used to screen HIV-positive persons at risk of neurocognitive disorders.

Changes in Cerebrospinal Fluid, Liver and Intima-media-thickness Biomarkers in Patients with HIV-associated Neurocognitive Disorders Randomized to a Less Neurotoxic Treatment Regimen.

The prevalence of neurocognitive impairment in people living with HIV is estimated between 30 and 50%. The pathogenesis of HIV-associated neurocognitive disorders is complex and multifactorial. Aim of the study was to measure the change in CSF biomarkers, Fibroscan and IMT measurements in PLWH with HAND randomized to a less neurotoxic regimen, or continuing their treatment. Adult patients with HAND were screened and enrolled if presenting no major resistance associated mutations, no HIV viral replication, not on efavirenz or darunavir, with R5-tropic HIV and without major confounding conditions. Lumbar puncture, IMT and Fibroscan measurements were performed. After 1:1 randomization to a less neurotoxic regimen consisting of darunavir/cobicistat plus emtricitabine plus maraviroc, or mantaining actual care, tests were repeated after 24 weeks: CSF biomarkes (HIV RNA, tau, p-tau, Beta-amyloid1-42, S100Beta and neopterin) were included. Non-parametric tests (Mann-Whitney and Wilcoxon's) were used. 28 participants completed the study. Male and European ancestry were prevalent; median age was 55 years (51-60). All patients were virally suppressed; median CD4 + count was 626 cell/uL (469-772). Baseline characteristics were similar between the study arms. A significant decrease in CSF p-tau and an increase in CSF neopterin and NFL were observed. We observed a significant reduction in liver stiffness at W24. Despite a small sample size we observed changes in neuromarkers and in hepatic stiffness in patients randomized to the experimental arm. We observed changes in CSF biomarkers (lower phosphorylated-tau and higher neopterin and NFL) that need to be replicated in large cohorts. Subclinical neurotoxicity may be observed in patients with HAND and warrants prospective studies.

Sequential or Combination Treatments as Rescue Therapies in Immunocompromised Patients with Persistent SARS-CoV-2 Infection in the Omicron Era: A Case Series.

Prolonged SARS-CoV-2 infections are widely described in immunosuppressed patients, but safe and effective treatment strategies are lacking. We aimed to outline our approach to treating persistent COVID-19 in patients with immunosuppression from different causes. In this case series, we retrospectively enrolled all immunosuppressed patients with persistent SARS-CoV-2 infections treated at our centers between March 2022 and February 2023. Patients received different sequential or combination regimens, including antivirals (remdesivir, nirmatrelvir/ritonavir, or molnupiravir) and/or monoclonal antibodies (mAbs) (tixagevimab/cilgavimab or sotrovimab). The main outcome was a complete virological response (negative SARS-CoV-2 RT-PCR on nasopharyngeal swabs) at the end of treatment. Fifteen patients were included as follows: eleven (11/15; 73%) with hematological disease and four (4/15; 27%) with recently diagnosed HIV/AIDS infection. Six patients (6/15; 40%) received a single antiviral course, four patients (4/15; 27%) received an antiviral and mAbs sequentially, and two patients (13%) received three lines of treatment (a sequence of three antivirals or two antivirals and mAbs). A combination of two antivirals or one antiviral plus mAbs was administered in three cases (3/15, 20%). One patient died while still positive for SARS-CoV-2, while fourteen (14/15; 93%) tested negative within 16 days after the end of treatment. The median time to negativization since the last treatment was 2.5 days. Both sequential and combination regimens used in this study demonstrated high efficacy and safety in the high-risk group of immunosuppressed patients.

HIV-DNA decrease during treatment in primary HIV-1 infection with three different drug regimens: Italian Network of Acute HIV Infection (INACTION) clinical trial.

As the introduction of antiretroviral therapy (ART) during primary HIV-1 infection (PHI) could restrict the establishment of HIV reservoirs, we aimed to assess the effect of three different ART regimens on HIV-DNA load in people living with HIV (PLWH), who started ART in PHI. Randomized, open-label, multicentric study, including subjects in PHI (defined as an incomplete HIV-1 Western blot and detectable plasma HIV-RNA) in the Italian Network of Acute HIV Infection cohort. Participants were randomly assigned (10:10:8) to a fixed-dose combination of tenofovir alafenamide fumarate (TAF) 10 mg plus emtricitabine (FTC) 200 mg, darunavir 800 mg, and cobicistat 150 mg once daily (group A), or TAF 25 mg plus FTC 200 mg, dolutegravir 50 mg once daily (group B), or an intensified four-drug regimen (TAF 10 mg plus FTC 200 mg, dolutegravir 50 mg, darunavir 800 mg, and cobicistat 150 mg once daily) (group C). The primary endpoint was the decrease of HIV-DNA copies/106 peripheral blood mononuclear cells (PBMCs) at weeks (W) 12 and 48. Secondary endpoints were increased in CD4+ cells and in CD4+/CD8+ ratio and percentage of PLWH reaching undetectable HIV-RNA. HIV-DNA was quantified by Droplet Digital PCR (Biorad QX100) and normalized to RPP30 reference gene. This study was registered in ClinicalTrials.gov (number NCT04225325). Among 78 participants enrolled, 30 were randomized to group 1, 28 to group 2, and 20 to group 3. At baseline, median CD4+ count was 658/µL (476-790), HIV-RNA 5.37 (4.38, 6.12) log10 copies/mL, without statistical difference in their change among groups at weeks 12 and 48 (p = 0.432 and 0.234, respectively). The trial was prematurely discontinued for slow accrual and for COVID-19 pandemic-associated restrictions. In the per-protocol analysis, PLWH (n = 72) with undetectable viral load was 54.3% at W12 and 86.4% at W48. Interestingly, the CD4/CD8 ratio progressively increased over time, up to normalization in almost half of the cohort by week 48, despite a deflection in group 3; no difference was observed by the Fiebig stage (I-III vs. IV-VI). HIV-DNA decreased from 4.46 (4.08, 4.81) log10 copies/106 PBMCs to 4.22 (3.79, 4.49) at week 12, and 3.87 (3.46, 4.34) at week 48, without difference among groups. At multivariable analysis, HIV-DNA delta at W48 was associated only with the increase of CD4+ count by 100 cells/mm3 but not with the Fiebig stage, the CD4+/CD8+ ratio, and treatment arm, despite a higher decrease in group 3. Six adverse events were recorded during our study, which did not cause any withdrawal from the study. We observed a decrease in HIV-DNA from baseline to W48 in PLWH treated during PHI, associated with an increase in CD4+ count, unrelated to the treatment arm.

A case of histological diagnosis of Toxoplasma gondii myositis in a person living with HIV.

We report the case of a 58-year-old male with a recent diagnosis of HIV infection admitted for progressive muscular weakness and psychomotor impairment. Cerebrospinal examination documented a mild hyperproteinorrachia, with normal cells count and reduced glycorrhachia. Brain gadolinium-enhanced MRI showed bilateral T2 and FLAIR hyperintensities in the nucleo-capsular region and irregular contrast-enhancement of the globi pallidi and the right putamen. The histologic analysis of a quadriceps biopsy showed several foci of inflammatory infiltrates with concomitant muscular fiber atrophy and degeneration. Scattered intracytoplasmic inclusions were observed in muscle fibers, representing the main pathological feature. A positive PCR for Toxoplasma gondii and a Toxoplasma gondii specific monoclonal antibody immunohistochemical staining confirmed the diagnosis.

Real-Life Experience of Continuously Infused Ceftolozane/Tazobactam in Patients with Bronchiectasis and Multidrug-Resistant Pseudomonas aeruginosa Infection in the Outpatient Setting.

(1) Background: Ceftolozane/tazobactam (C/T) is a novel ß-lactam/ß-lactamase inhibitor with excellent activity against the multidrug-resistant (MDR) P. aeruginosa. Continuous infusion (CI) dosing allows the optimization of pharmacokinetic and pharmacodynamic (PK/PD) properties of ß-lactam antibiotics and may support patients' treatment as outpatients. (2) Methods: Adult patients receiving their entire course of C/T as a CI in the outpatient setting were retrospectively included in the study. The primary outcome evaluated was clinical resolution. The secondary outcomes evaluated were PK/PD target attainment (ƒT > 4 × MIC) and microbiologic clearance at the end of treatment. Therapeutic drug monitoring to assess C/T concentration was performed. (3) Results: Three patients were enrolled in the study and received 9 g of C/T in CI every 24 h. One patient received an additional course of antimicrobial therapy due to disease exacerbation six months after initial treatment, accounting for four evaluated treatments. The primary outcome was achieved in 3/4 treatments and the secondary outcome was achieved in 4/4 and 3/3, respectively. In all patients, free ceftolozane concentrations were >10 times higher than the EUCAST breakpoint (4 mg/L). (4) Conclusions: Elastomeric infusion of C/T delivered in CI can be an effective and convenient way to treat acute diseases caused by MDR-P. aeruginosa, avoid hospital admission, and contribute to infection control strategies. Despite the small number of enrolled patients, clinical and microbiological results support this strategy.

Extended and Continuous Infusion of Novel Protected ß-Lactam Antibiotics: A Narrative Review.

Consolidated data from pharmacokinetic and pharmacodynamic studies support the administration of ß-lactam antibiotics in prolonged infusion (i.e., extended or continuous) to optimize therapeutic efficacy by increasing the probability of attaining maximal bactericidal activity. This is the longest possible time during which the free drug concentrations are approximately four-fold the minimum inhibitory concentration between dosing intervals. In the context of antimicrobial stewardship strategies, achieving aggressive pharmacokinetic and pharmacodynamic targets is an important tool in the management of multi-drug resistant (MDR) bacterial infections and in the attainment of mutant preventing concentrations. However, prolonged infusion remains an unexploited resource. Novel ß-lactam/ß-lactamase inhibitor (ßL/ßLI) combinations (ceftolozane-tazobactam, ceftazidime-avibactam, meropenem-vaborbactam, and imipenem-cilastatin-relebactam) have been released in recent years to face the emerging challenge of MDR Gram-negative bacteria. Pre-clinical and real-life evidence has confirmed the promising role of prolonged infusion of these molecules in specific settings and clinical populations. In this narrative review we have summarized available pharmacological and clinical data, future perspectives, and current limitations of prolonged infusion of the novel protected ß-lactams, their application in hospital settings and in the context of outpatient parenteral antimicrobial therapy.

Cerebrospinal Fluid CXCL13 as Candidate Biomarker of Intrathecal Immune Activation, IgG Synthesis and Neurocognitive Impairment in People with HIV.

Plasma C-X-C-motif chemokine ligand-13 (CXCL13) has been linked to disease progression and mortality in people living with HIV (PLWH) and is a candidate target for immune-based strategies for HIV cure. Its role in central nervous system (CNS) of PLWH has not been detailed. We described CSF CXCL13 levels and its potential associations with neurological outcomes. Cross-sectional study enrolling PLWH without confounding for CXCL13 production. Subjects were divided according to CSF HIV-RNA in undetectable (< 20 cp/mL) and viremics. CSF CXCL13, and biomarkers of blood-brain barrier (BBB) impairment, intrathecal synthesis, and immune activation were measured by commercial immunoturbidimetric and ELISA assays. All subjects underwent neurocognitive assessment. Sensitivity analyses were conducted in subjects with intact BBB only. 175 participants were included. Detectable CSF CXCL13 was more common in the viremic (31.4%) compared to the undetectable group (13.5%; OR 2.9 [1.4-6.3], p = 0.006), but median levels did not change (15.8 [8.2-91.0] vs 10.0 [8.1-14.2] pg/mL). In viremics (n = 86), CXCL13 associated with higher CSF HIV-RNA, proteins, neopterin, intrathecal synthesis and BBB permeability. In undetectable participants (n = 89), CXCL13 associated with higher CD4+T-cells count, CD4/CD8 ratio, CSF proteins, neopterin, and intrathecal synthesis. The presence of CXCL13 in the CSF of undetectable participants was associated with increased odds of HIV-associated neurocognitive disorders (58.3% vs 28.6%, p = 0.041). Sensitivity analyses confirmed all these findings. CXCL13 is detectable in the CSF of PLWH that show increased intrathecal IgG synthesis and immune activation. In PLWH with CSF viral suppression, CXCL13 was also associated with neurocognitive impairment.