Predictive biomarkers of mortality in patients with severe COVID-19 hospitalized in intensive care unit.

Objectives: This study was performed to identify predictive markers of worse outcomes in patients with severe COVID-19 in an intensive care unit. Methods: Sixty patients with severe COVID-19, hospitalized in the Intensive Care Unit (ICU) between March and July 2021, were stratified into two groups according to the outcome survivors and non-survivors. After admission to the ICU, blood samples were collected directly for biomarker analysis. Routine hematological and biochemical biomarkers, as well as serum levels of cytokines, chemokines, and immunoglobulins, were investigated. Results: Lymphopenia, neutrophilia, and thrombocytopenia were more pronounced in non-surviving patients, while the levels of CRP, AST, creatinine, ferritin, AST, troponin I, urea, magnesium, and potassium were higher in the non-surviving group than the survival group. In addition, serum levels of IL-10, CCL2, CXCL9, and CXCL10 were significantly increased in patients who did not survive. These changes in the biomarkers evaluated were associated with increased mortality in patients with severe COVID-19. Conclusion: The present study confirmed and expanded the validity of laboratory biomarkers as indicators of mortality in severe COVID-19.

HIV-Induced Thymic Insufficiency and Aging-Related Immunosenescence on Immune Reconstitution in ART-Treated Patients.

The mechanisms underlying unsatisfactory immune reconstitution in HIV-1 positive patients under ART have not been fully elucidated, even after years of investigation. Thus, this study aimed to assess the correlation between age and thymic production profile, and its influence on inadequate immunological recovery. Here, 44 ART-treated patients with undetectable plasma HIV-1 load (<40 copies/mL) were classified as 31 immunological responders (IR) and 13 immunological non-responders (INR), according to their CD4+ T-cell count after 18 months of ART. The thymic function was assessed by identifying recent thymic emigrants (RTEs) CD4+ T cells (CD4+/CD45RA+CD31+) in PBMCs using flow cytometry. Clinical data were also analyzed from medical records. The INR group showed a higher age at ART initiation (41 ± 3.0) compared to the IR (33.7 ± 2.1) group (p = 0.041). Evaluating RTE CD4+ T-cells, we observed a lower percentage in the INR group (19.5 ± 6.3) compared to the IR group (29.9 ± 11.5) (p = 0.012). There was a strong negative correlation between age at ART initiation and RTE CD4+ T-cells in INRs (r = -0.784, p = 0.004). Our study has highlighted the thymic insufficiency and aging-related immunosenescence with unsatisfactory immunological recovery during ART in HIV-1 positive patients.

Thymic Exhaustion and Increased Immune Activation Are the Main Mechanisms Involved in Impaired Immunological Recovery of HIV-Positive Patients under ART.

Decades of studies in antiretroviral therapy (ART) have passed, and the mechanisms that determine impaired immunological recovery in HIV-positive patients receiving ART have not been completely elucidated yet. Thus, T-lymphocytes immunophenotyping and cytokines levels were analyzed in 44 ART-treated HIV-positive patients who had a prolonged undetectable plasma viral load. The patients were classified as immunological non-responders (INR = 13) and immunological responders (IR = 31), according to their CD4+ T cell levels. Evaluating pre-CD4+ levels, we observed a statistically significant trend between lower CD4+ T cell levels and INR status (Z = 3.486, p < 0.001), and during 18 months of ART, the CD4+ T cell levels maintained statistical differences between the INR and IR groups (WTS = 37.252, p < 0.001). Furthermore, the INRs were associated with an elevated age at ART start; a lower pre-treatment CD4+ T cell count and a percentage that remained low even after 18 months of ART; lower levels of recent thymic emigrant (RTE) CD4+ T cell (CD45RA + CD31+) and a naïve CD4+ T cell (CD45RA + CD62L+); higher levels of central memory CD4+ T cells (CD45RA-CD62L+); and higher immune activation by CD4+ expressing HLA-DR+ or both (HLA-DR+ and CD38+) when compared with IRs. Our study demonstrates that thymic exhaustion and increased immune activation are two mechanisms substantially implicated in the impaired immune recovery of ART-treated HIV patients.

Performance of IS6110-LAMP assay for detection of Mycobacterium tuberculosis complex in blood and urine samples from patients with extrapulmonary tuberculosis.

BACKGROUND: The diagnosis of extrapulmonary tuberculosis (EPTB) shows numerous difficulties because of non-specific symptomatology and low sensitivity of conventional methods. Loop-mediated isothermal amplification (LAMP) is a fast and low-cost technique, which can amplify under isothermal conditions an amount of target DNA copies into approximately a billion copies. OBJECTIVE: The present study aimed to evaluate a IS6110-LAMP system for Mycobacterium tuberculosis detection in blood and urine samples from patients with EPTB. METHODS: The collected samples (n = 122) were stratified in two groups: Group EPTB - patient samples with confirmed EPTB (n = 61); Group non-TB - patient samples without TB (n = 61). The urine samples underwent decontamination, and the components of blood samples were separated (plasma and PBMC). DNA extractions were performed in all biological samples followed by IS6110-LAMP assay technique. The detection limit was evaluated through dilution curves (1:10) using Mtb reference strain (H37Rv) genomic DNA. FINDINGS: The detection limit of IS6110-LAMP was 10 fg/µL (∼10-20 bacilli/µL). The IS6110-LAMP technique sensitivity and specificity were 95.65 % and 79.25 %, respectively, with a general kappa agreement index of 0.762. MAIN CONCLUSIONS: Based on these results, IS6110-LAMP test showed considerable diagnostic parameters, being able to aid in the speed and accuracy of the final EPTB diagnosis.

Differences in pyroptosis of recent thymic emigrants CD4+ T Lymphocytes in ART-treated HIV-positive patients are influenced by sex.

Pyroptosis cell death in recent thymus emigrants (RTE) CD4+ T lymphocytes plays an important role on HIV-1 infection as a cause of CD4+ T cell depletion, being influenced by several factors, among them, the sex. Thus, the aim of this study was evaluated pyroptosis levels in RTE CD4+ T lymphocytes of individuals under antiretroviral therapy (ART) stratified by sex. Thirty-seven ART-treated HIV-positive patients (22 females and 15 males) and 12 (seven females and five males) clinically health subjects were recruited. Analysis by flow-cytometry of RTE CD4+ cells (CD4+ CD31+ /fluorescent-labeled inhibitors of caspases-Caspase-1+) were performed. Clinical and sociodemographic aspects were also evaluated from medical records. We observed statistically higher levels of pyroptosis RTE CD4+ T cells in male individuals (69.3%) compared with female group (39.1%) (P = 0.0356). Pre- and post-treatment CD4+ T cell counts were also higher in women than men (P = 0.004 and P = 0.012, respectively). Our data provides important evidence of the sex as a potential predictor of immunological reconstitution in ART-treated individuals.

CCR5 genotype and pre-treatment CD4+ T-cell count influence immunological recovery of HIV-positive patients during antiretroviral therapy.

This study was performed to assess the association of CCR5Δ32 and SDF1-3'A polymorphisms with immunological recovery failure and to investigate the influence of sociodemographic and clinical data on immune reconstitution in human immunodeficiency virus (HIV)-positive patients during antiretroviral therapy (ART). Two hundred and forty-eight HIV-positive patients under ART with undetectable plasma viral load (<40 copies/mL) were enrolled in this study and classified into two groups according to their CD4+ T-cell count changes: immunological responders (CD4+ T-cell count gain ≥ 200/µL or ≥ 30% compared with baseline) and immunological non-responders (CD4+ T-cell count gain < 200/µL or < 30% compared with baseline). DNA extraction was performed followed by CCR5Δ32 and SDF1-3'A genotyping. Sociodemographic and clinical data were evaluated from medical records. The logistic regression model showed that heterozygosity for CCR5Δ32 allele and lower pre-treatment CD4+ T-cell count (<500 cells/µL) were statistically associated with immunological recovery failure (OR = 5.873, 95%CI = 1.204-28.633, P = 0.028 and OR = 10.00, 95%CI = 3.224-31.016, P = 0.028, respectively). No association of SDF1-3'A polymorphism with immune reconstitution failure was found. Additionally, we observed that there was a statistically significant difference between lower CD4+ T-cell count and INR status than the IR group (Z = 4.687, P < 0.001). Our results demonstrated, through a logistic regression model, that CCR5Δ32 polymorphism and pre-treatment CD4+ T-cell count have significant influence on immune reconstitution of HIV-positive patients during ART. These findings highlight some immunological factors associated with poor CD4+ T-lymphocytes recovery, which affect immune response level of ART-treated HIV-positive patients.

Increased risk of dizziness in human immunodeficiency virus-infected patients taking zidovudine and efavirenz combination: a Brazilian cohort study.

OBJECTIVES: Neuropsychiatric adverse effects (NPAE) related to efavirenz, mainly dizziness, is detrimental to human immunodeficiency virus (HIV) treatment. Our study aims at evaluating if zidovudine use potentiates the risk of dizziness related to efavirenz when used together and whether there are significant differences in over time distribution of this NPAE and others relatively frequents regarding efavirenz regimen without zidovudine. METHODS: Human immunodeficiency virus-infected patients under efavirenz-containing different therapy were enrolled. A retrospective analysis of official medical records was accomplished to collect clinical data regarding NPAE occurrence and severity. Univariate statistic and statistical model based on survival analyses were performed. KEY FINDINGS: One hundred sixty-two patients were included, of these seventy-seven (47.5%) had NPAE reported, such as dizziness (more frequent), depression and insomnia. Univariate statistical analysis demonstrated that the combined use of efavirenz with zidovudine increased the NPAE risk (OR: 2.5; P-value: 0.008), mainly dizziness risk (OR: 3.5; P-value: 0.009) and survival analysis showed that such combination is associated with dizziness occurrence faster (HR: 2.9; P-value: 0.02). CONCLUSIONS: The results may contribute to clarify the dizziness occurrence dynamics in therapy with efavirenz and zidovudine by identifying susceptibilities and assisting in the choice of combined antiretroviral therapy.

Immunological recovery failure in cART-treated HIV-positive patients is associated with reduced thymic output and RTE CD4+ T cell death by pyroptosis.

Despite more than three decades of studies and advances in combination antiretroviral therapy (cART) against human immunodeficiency virus (HIV), the mechanisms that precisely determine immune reconstitution failure have not been completely elucidated yet. Thus, this study aimed to investigate the thymic function, immune activation, and cell death by pyroptosis and apoptosis in virologically suppressed HIV-positive patients receiving cART. Immunophenotyping analyses were performed in 57 cART-treated HIV-infected patients with undetectable plasma viral load, who were classified as immunological nonresponders (INR = 29) and immunologic responders (IR = 28). Sociodemographic and clinical data were also assessed from medical records. Twelve healthy volunteers were also included in this study. The INR showed lower pretreatment CD4+ T cell count that remained low even after 1 yr of treatment, lower CD4/CD8 ratio, lower percentage of recent thymic emigrant (RTE) CD4+ T cell (CD45RA+CD31+) and naïve CD4+ T cell (CD45RA+CD62L+), higher levels of effector memory CD4+ T cells (CD45RA-CD62L-), and higher pyroptosis levels of RTE CD4+ T cells (CD31+FLICA-Caspase1+) when compared with IR. Our findings indicate that reduced thymic function and RTE CD4+ T cell death by pyroptosis are the major mechanisms of immunological recovery failure in HIV-infected patients receiving cART.

IL18 gene polymorphism and its influence on CD4+ T-cell recovery in HIV-positive patients receiving antiretroviral therapy.

BACKGROUND: Pyroptosis has been reported to be critical in human immunodeficiency virus type 1 (HIV-1) pathogenesis and acquired immunodeficiency syndrome (AIDS) progression. Even after achieving viral suppression to undetectable levels during antiretroviral therapy (ART), exacerbated CD4+ T-cell death by pyroptosis has been suggested as one of the main causes of immunological non-response. Thus, variants in genes of pyroptosis pathway were studied in individuals with poor CD4+ T-cell reconstitution under antiretroviral therapy against HIV-1. METHODS: 248 virologically suppressed ART-treated patients, 126 immunological non-responders (INR) and 122 immunological responders (IR) were recruited. Genotyping was performed using TaqMan probe-based realtime PCR platform. Genotype-guided flow cytometry analysis with general and recent thymic emigrant (RTE) CD4+ T-cells in pyroptosis was performed based on associated polymorphisms. RESULTS: Both IL18 rs187238 G allele and GG genotype were associated as protection factors against poor CD4+ T-cell recovery (OR = 0.22; 95%CI = 0.50-0.77; P = .010 and OR = 0.58; 95%CI = 0.36-0.93; P = .022, respectively). It was demonstrated a statistical association between IL18 rs187238 genotypes of ART-treated patients and death by Caspase-1 levels (P = .020). The GG genotype showed lower pyroptotic RTE CD4+ T-lymphocytes levels in the ART-treated groups comparing with CC (P = .029) and CG (P = .018) genotypes, suggesting that the G allele presence may be related to a lower IL-18 production and thus reduced dead CD4+ T-cells levels by Caspase-1. CONCLUSION: We observed that IL18 G variant allele and genotype were associated with a better immunological response, which may influence on immunological recovery of HIV-positive patients receiving antiretroviral therapy, and low Caspase-1 activity levels was observed on GG genotype when compared CC genotypes.