Although highly active antiretroviral therapy has enabled constant progress in reducing HIV-1 replication, in some patients who are “aviremic” during treatment, the problem of insufficient immune ...restoration remains, and this exposes them to the risk of immune deficiency–associated pathologies. Various mechanisms may combine and account for this impaired immunologic response to treatment. A first possible mechanism is immune activation, which may be because of residual HIV production, microbial translocation, co-infections, immunosenescence, or lymphopenia per se. A second mechanism is ongoing HIV replication. Finally, deficient thymus output, sex, and genetic polymorphism influencing apoptosis may impair immune reconstitution. In this review we will discuss the tools at our disposal to identify the various mechanisms at work in a given patient and the specific therapeutic strategies we could propose based on this etiologic diagnosis.
•Knowledge of the extent of COVID-19 epidemic and the level of herd immunity is urgently needed•We develop a Multiplex bead-based IgG detection tool for pathogenic human coronaviruses.•The novel ...assay is highly sensitive and specific.•Our novel assay is more sensitive than a commercial EIA.•We show that an immunoassay using a single antigen can lead to false positive results.
Knowledge of the COVID-19 epidemic extent and the level of herd immunity is urgently needed to help manage this pandemic.
We used a panel of 167 samples (77 pre-epidemic and 90 COVID-19 seroconverters) and SARS-CoV1, SARS-CoV2 and MERS-CoV Spike and/or Nucleopcapsid (NC) proteins to develop a high throughput multiplex screening assay to detect IgG antibodies in human plasma. Assay performances were determined by ROC curves analysis. A subset of the COVID-19+ samples (n = 36) were also tested by a commercial NC-based ELISA test and the results compared with those of the novel assay.
On samples collected ≥14 days after symptoms onset, the accuracy of the assay is 100 % (95 % CI: 100−100) for the Spike antigen and 99.9 % (95 % CI:99.7−100) for NC. By logistic regression, we estimated that 50 % of the patients have seroconverted at 5.7 ± 1.6; 5.7 ± 1.8 and 7.9 ± 1.0 days after symptoms onset against Spike, NC or both antigens, respectively and all have seroconverted two weeks after symptoms onset. IgG titration in a subset of samples showed that early phase samples present lower IgG titers than those from later phase. IgG to SARS-CoV2 NC cross-reacted at 100 % with SARS-CoV1 NC. Twenty-nine of the 36 (80.5 %) samples tested were positive by the commercial ELISA while 31/36 (86.1 %) were positive by the novel assay.
Our assay is highly sensitive and specific for the detection of IgG antibodies to SARS-CoV2 proteins, suitable for high throughput epidemiological surveys. The novel assay is more sensitive than a commercial ELISA.
To describe the evolving epidemiology, management, and risk factors for death of invasive Candida infections in intensive care units (ICUs).
Prospective, observational, national, multicenter study.
...One hundred eighty ICUs in France.
Between October 2005 and May 2006, 300 adult patients with proven invasive Candida infection who received systemic antifungal therapy were included.
None.
One hundred seven patients (39.5%) with isolated candidemia, 87 (32.1%) with invasive candidiasis without documented candidemia, and 77 (28.4%) with invasive candidiasis and candidemia were eligible. In 37% of the cases, candidemia occurred within the first 5 days after ICU admission. C. albicans accounted for 57.0% of the isolates, followed by C. glabrata (16.7%), C. parapsilosis (7.5%), C. krusei (5.2%), and C. tropicalis (4.9%). In 17.1% of the isolates, the causative Candida was less susceptible or resistant to fluconazole. Fluconazole was the empirical treatment most commonly introduced (65.7%), followed by caspofungin (18.1%), voriconazole (5.5%), and amphotericin B (3.7%). After identification of the causative species and susceptibility testing results, treatment was modified in 86 patients (31.7%). The case fatality ratio in ICU was 45.9% and did not differ significantly according to the type of episode. Multivariate analysis showed that factors independently associated with death in ICU were type 1 diabetes mellitus (odds ratio OR 4.51; 95% confidence interval CI 1.72-11.79; p = 0.002), immunosuppression (OR 2.63; 95% CI 1.35-5.11; p = 0.0045), mechanical ventilation (OR 2.54; 95% CI 1.33-4.82; p = 0.0045), and body temperature >38.2 degrees C (reference, 36.5-38.2 degrees C; OR 0.36; 95% CI 0.17-0.77; p = 0.008).
More than two thirds of patients with invasive candidiasis in ICU present with candidemia. Non-albicans Candida species reach almost half of the Candida isolates. Reduced susceptibility to fluconazole is observed in 17.1% of Candida isolates. Mortality of invasive candidiasis in ICU remains high.
Coagulase-negative staphylococci (CoNS) and especially
are responsible for health care infections, notably in the presence of foreign material (e.g., venous or central-line catheters). ...Catheter-related bacteremia (CRB) increases health care costs and mortality. The aim of our study was to evaluate the impact of 15 days of antibiotic exposure (ceftobiprole, daptomycin, linezolid and vancomycin) at sub-inhibitory concentration on the resistance, fitness and genome evolution of 36 clinical strains of
responsible for CRB. Resistance was evaluated by antibiogram, the ability to adapt metabolism by the Biofilm Ring test
and the in vivo nematode virulence model. The impact of antibiotic exposure was determined by whole-genome sequencing (WGS) and biofilm formation experiments. We observed that
strains presented a wide variety of virulence potential and biofilm formation. After antibiotic exposure,
strains adapted their fitness with an increase in biofilm formation. Antibiotic exposure also affected genes involved in resistance and was responsible for cross-resistance between vancomycin, daptomycin and ceftobiprole. Our data confirmed that antibiotic exposure modified bacterial pathogenicity and the emergence of resistant bacteria.
Total HIV DNA is a standard marker to monitor the HIV reservoir in people living with HIV. We investigated HIV DNA quantification accuracy by a real-time PCR kit (qPCR) and digital PCR (dPCR) method ...within the same set of primers and probes. Among 48 aviremic patients followed for up to 7 years with qPCR, the mean coefficient of variation of total HIV DNA between two successive measurements was 77% (± 0.42log
HIVDNA copies/10
PBMC). The total HIV DNA quantified by the two PCR methods has a high correlation (0.99 and 0.83, for 8E5 and PLHIV samples, respectively), but we observed better repeatability and reproducibility of the dPCR compared to the qPCR (CV of 11.9% vs. 24.7% for qPCR, p-value = 0.024). Furthermore, we highlighted a decay of the number of HIV copies in the 8E5 cell line qPCR standard over time (from 0.73 to 0.43 copies per cell), contributing to variations of HIV DNA results in patients whose HIV reservoir should be theoretically stabilized. Our study highlighted that absolute quantification of total HIV DNA by dPCR allows more accurate monitoring of the HIV reservoir than qPCR in patients under prolonged antiretroviral therapy.
Summary Background Patients with HIV on antiretroviral therapy might benefit from regimen simplification to reduce pill burden and dosing frequency. We aimed to assess the safety and efficacy of ...simplifying the treatment regimen for adults with virologically suppressed HIV infection from a ritonavir-boosted protease inhibitor and emtricitabine plus tenofovir disoproxil fumarate (tenofovir) regimen to coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir. Methods STRATEGY-PI is a 96 week, international, multicentre, randomised, open-label, phase 3b trial in which HIV-infected adults with a plasma HIV-1 RNA viral load of less than 50 copies per mL for at least 6 months who were taking a ritonavir-boosted protease inhibitor with emtricitabine plus tenofovir were randomly assigned (2:1) either to switch to coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir or to continue on their existing regimen. Key eligibility criteria included no history of virological failure, no resistance to emtricitabine and tenofovir, and creatinine clearance of 70 mL/min or higher. Neither participants nor investigators were masked to group allocation. The primary endpoint was the proportion of participants with a viral load of less than 50 copies per mL at week 48, based on a US Food and Drug Administration snapshot algorithm for the modified intention-to-treat population, which excluded major protocol violations (prohibited resistance or not receiving a protease inhibitor at baseline). We prespecified non-inferiority with a 12% margin; if non-inferiority was established, superiority was tested as per a prespecified sequential testing procedure. This trial is registered at ClinicalTrials.gov , number NCT01475838. Findings Between Dec 12, 2011, and Dec 20, 2012, 433 participants were randomly assigned and received at least one dose of study drug. Of these participants, 293 were assigned to switch to the simplified regimen (switch group) and 140 to remain on their existing regimen (no-switch group); after exclusions, 290 and 139 participants, respectively, were analysed in the modified intention-to-treat population. At week 48, 272 (93·8%) of 290 participants in the switch group maintained a viral load of less than 50 copies per mL, compared with 121 (87·1%) of 139 in the no-switch group (difference 6·7%, 95% CI 0·4–13·7; p=0·025). The statistical superiority of the simplified regimen was mainly caused by a higher proportion of participants in the no-switch group than in the switch group discontinuing treatment for non-virological reasons; virological failure was rare in both groups (two 1% of 290 vs two 1% of 139). We did not detect any treatment-emergent resistance in either group. Adverse events leading to discontinuation were rare in both groups (six 2% of 293 vs four 3% of 140). Switching to the simplified regimen was associated with a small, non-progressive increase from baseline in serum creatinine concentration. Nausea was more common in the switch group than in the no-switch group, but rates of diarrhoea and bloating decreased compared with baseline from week 4 to week 48 in the switch group, whereas there were generally no changes for these symptoms in the no-switch group. Interpretation Coformulated elvitegravir, cobicistat, emtricitabine, and tenofovir might be a useful regimen simplification option for virologically supressed adults with HIV taking a multitablet ritonavir-boosted protease inhibitor regimen. Funding Gilead Sciences.
Background
Reversible cerebral vasoconstriction syndrome (RCVS) is a common cause of thunderclap headache (TCH), mainly recurrent, sometimes associated with seizures and/or neurological deficit. ...Association with amnesia is exceptional. We report a case series of RCVS concomitant with transient global amnesia (TGA) and propose pathophysiologic hypotheses.
Methods
We retrospectively reviewed clinical and radiological features of patients diagnosed with confirmed concomitant RCVS and TGA between 2012 and 2018 in two specialized institutions.
Results
Two women aged 67 and 53, and a 64-year-old man had a first thunderclap headache triggered by an acute emotional stress, rapidly followed by TGA. Amnesia resolved within a few hours and RCVS was proven for all, with complete resolution of vasospasms within 3 months. All three patients had excellent outcome.
Conclusions
RCVS and TGA can occur simultaneously, which suggests common mechanisms such as aberrant responses to physical or emotional stress and cerebral vasoconstriction.
MicroRNAs (miRNAs) are single-stranded noncoding RNAs of 19 to 25 nucleotides that function as gene regulators and as a host cell defense against both RNA and DNA viruses. We provide evidence for a ...physiological role of the miRNA-silencing machinery in controlling HIV-1 replication. Type III RNAses Dicer and Drosha, responsible for miRNA processing, inhibited virus replication both in peripheral blood mononuclear cells from HIV-1-infected donors and in latently infected cells. In turn, HIV-1 actively suppressed the expression of the polycistronic miRNA cluster miR-17/92. This suppression was found to be required for efficient viral replication and was dependent on the histone acetyltransferase Tat cofactor PCAF. Our results highlight the involvement of the miRNA-silencing pathway in HIV-1 replication and latency.
Chronic immune activation persists in persons living with HIV-1 even though they are aviremic under antiretroviral therapy, and fuels comorbidities. In previous studies, we have revealed that ...virologic responders present distinct profiles of immune activation, and that one of these profiles is related to microbial translocation. In the present work, we tested in 140 HIV-1-infected adults under efficient treatment for a mean duration of eight years whether low-level viremia might be another cause of immune activation. We observed that the frequency of viremia between 1 and 20 HIV-1 RNA copies/mL (39.5 ± 24.7% versus 21.1 ± 22.5%, p = 0.033) and transient viremia above 20 HIV-1 RNA copies/mL (15.1 ± 16.9% versus 3.3 ± 7.2%, p = 0.005) over the 2 last years was higher in patients with one profile of immune activation, Profile E, than in the other patients. Profile E, which is different from the profile related to microbial translocation with frequent CD38+ CD8+ T cells, is characterized by a high level of CD4+ T cell (cell surface expression of CD38), monocyte (plasma concentration of soluble CD14), and endothelium (plasma concentration of soluble Endothelial Protein C Receptor) activation, whereas the other profiles presented low CD4:CD8 ratio, elevated proportions of central memory CD8+ T cells or HLA-DR+ CD4+ T cells, respectively. Our data reinforce the hypothesis that various etiological factors shape the form of the immune activation in virologic responders, resulting in specific profiles. Given the type of immune activation of Profile E, a potential causal link between low-level viremia and atherosclerosis should be investigated.
As HIV-infected adults on successful antiretroviral therapy (ART) are expected to have close to normal lifespans, they will increasingly develop age-related comorbidities. The objective of this ...cross-sectional study was to compare in the French Dat'AIDS cohort, the HIV geriatric population, aged 75 years and over, to the elderly one, aged from 50 to 74 years. As of Dec 2015, 16,436 subjects (43.8% of the French Dat'AIDS cohort) were aged from 50 to 74 (elderly group) and 572 subjects (1.5%) were aged 75 and over (geriatric group). Durations of HIV infection and of ART were slightly but significantly different, median at 19 and 18 years, and 15 and 16 years in the elderly and geriatric group, respectively. The geriatric group was more frequently at CDC stage C and had a lower nadir CD4. This group had been more exposed to first generation protease inhibitors and thymidine analogues. Despite similar virologic suppression, type of ART at the last visit significantly differed between the 2 groups: triple ART in 74% versus 68.2%, ART ≥ 4 drugs in 4.7% versus 2.7%; dual therapy in 11.6% versus 16.4% in the elderly group and the geriatric group, respectively. In the geriatric group all co-morbidities were significantly more frequent, except dyslipidemia, 4.3% of the elderly group had ≥4 co-morbidities versus18.4% in the geriatric group. Despite more co-morbidities and more advanced HIV infection the geriatric population achieve similar high rate of virologic suppression than the elderly population. A multidisciplinary approach should be developed to face the incoming challenge of aging HIV population.
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