Endothelial dysfunction, oxidative stress and low-grade endotoxemia in COVID-19 patients hospitalised in medical wards.

BACKGROUND: Endothelial dysfunction, assessed by flow-mediated dilation (FMD), is related to poor prognosis in patients with COVID-19 pneumonia (CP). In this study, we explored the interplay among FMD, NADPH oxidase type 2 (NOX-2) and lipopolysaccharides (LPS) in hospitalised patients with CP, community acquired pneumonia (CAP) and controls (CT). METHODS: We enrolled 20 consecutive patients with CP, 20 hospitalised patients with CAP and 20 CT matched for sex, age, and main cardiovascular risk factors. In all subjects we performed FMD and collected blood samples to analyse markers of oxidative stress (soluble Nox2-derived peptide (sNOX2-dp), hydrogen peroxide breakdown activity (HBA), nitric oxide (NO), hydrogen peroxide (H2O2)), inflammation (TNF-α and IL-6), LPS and zonulin levels. RESULTS: Compared with controls, CP had significant higher values of LPS, sNOX-2-dp, H2O2,TNF-α, IL-6 and zonulin; conversely FMD, HBA and NO bioavailability were significantly lower in CP. Compared to CAP patients, CP had significantly higher levels of sNOX2-dp, H2O2, TNF-α, IL-6, LPS, zonulin and lower HBA. Simple linear regression analysis showed that FMD inversely correlated with sNOX2-dp, H2O2, TNF-α, IL-6, LPS and zonulin; conversely FMD was directly correlated with NO bioavailability and HBA. Multiple linear regression analysis highlighted LPS as the only predictor of FMD. CONCLUSION: This study shows that patients with COVID-19 have low-grade endotoxemia that could activate NOX-2, generating increased oxidative stress and endothelial dysfunction.

External validation of the ADA score for predicting thrombosis among acutely ill hospitalized medical patients from the APEX Trial.

The ADA (Age-D-dimer-Albumin) score was developed to identify hospitalized patients at an increased risk for thrombosis in the coronavirus infectious disease-19 (COVID-19) setting. The study aimed to validate the ADA score for predicting thrombosis in a non-COVID-19 medically ill population from the APEX trial. The APEX trial was a multinational, randomized trial that evaluated the efficacy and safety of betrixaban vs. enoxaparin among acutely ill hospitalized patients at risk for venous thromboembolism. The study endpoints included the composite of arterial or venous thrombosis and its components. Metrics of model calibration and discrimination were computed for assessing the performance of the ADA score as compared to the IMPROVE score, a well-validated VTE risk assessment model. Among 7,119 medical inpatients, 209 (2.9%) had a thrombosis event up to 77 days of follow-up. The ADA score demonstrated good calibration for both arterial and venous thrombosis, whereas the IMPROVE score had adequate calibration for venous thrombosis (p > 0.05 from the Hosmer-Lemeshow test). For discriminating arterial and venous thrombosis, there was no significant difference between the ADA vs. IMPROVE score (c statistic = 0.620 [95% CI: 0.582 to 0.657] vs. 0.590 [95% CI: 0.556 to 0.624]; ∆ c statistic = 0.030 [95% CI: -0.022 to 0.081]; p = 0.255). Similarly, for discriminating arterial thrombosis, there was no significant difference between the ADA vs. IMPROVE score (c statistic = 0.582 [95% CI: 0.534 to 0.629] vs. 0.609 [95% CI: 0.564 to 0.653]; ∆ c statistic = -0.027 [95% CI: -0.091 to 0.036]; p = 0.397). For discriminating venous thrombosis, the ADA score was modestly superior to the IMPROVE score (c statistic = 0.664 [95% CI: 0.607 to 0.722] vs. 0.573 [95% CI: 0.521 to 0.624]; ∆ c statistic = 0.091 [95% CI: 0.011 to 0.172]; p = 0.026). The ADA score had a higher sensitivity (0.579 [95% CI: 0.512 to 0.646]; vs. 0.440 [95% CI: 0.373 to 0.507]) but lower specificity (0.625 [95% CI: 0.614 to 0.637] vs. 0.747 [95% CI: 0.737 to 0.758]) than the IMPROVE score for predicting thrombosis. Among acutely ill hospitalized medical patients enrolled in the APEX trial, the ADA score demonstrated good calibration but suboptimal discrimination for predicting thrombosis. The findings support the use of either the ADA or IMPROVE score for thrombosis risk assessment. The applicability of the ADA score to non-COVID-19 populations warrants further research.Clinical Trial Registration: http://www.clinicaltrials.gov . Unique identifier: NCT01583218.

Association between PaO2/FiO2 ratio and thrombotic events in COVID-19 patients.

PaO2/FiO2 (P/F ratio) is considered a marker of hypoxia/hypoxemia and mortality. Several prothrombotic changes are associated with the decrease of P/F ratio. The role of P/F ratio in patients with arterial and venous thrombosis remains unclear. The aim of this study was to assess in patients with coronavirus disease 2019 (COVID-19), the association between P/F ratio and arterial/venous thrombosis. One thousand and four hundred and six COVID-19 patients were recruited; 289 (21%) patients had P/F ratio < 200 and 1117 (79%) ≥ 200. Compared to the patients with P/F ratio ≥ 200, those with P/F ratio < 200 were older and with higher levels of glycemia, D-dimer and lower levels of albumin. Multiple linear regression analysis showed that albumin (standardized coefficient ß:  0.156; SE: 0.001; p = 0.0001) and D-dimer (standardized coefficient ß: -0.135; SE: 0.0001; p = 0.0001) were associated with P/F ratio. During the hospitalization 159 patients were transferred in intensive care unit (ICU), 253 patients died, 156 patients had arterial or venous thrombotic events. A bivariate logistic analysis was performed to analyze the predictors of thrombosis in COVID-19 patients; P/F ratio < 200 (Odds Ratio: [OR] 1.718, 95% Confidence Interval [CI] 1.085-2.718, p = 0.021), albumin (OR 1.693, 95% CI 1.055-2.716, p = 0.029), D-dimer (OR 3.469, 95% CI 2.110-5.703, p < 0.0001), coronary artery disease (CAD) (OR 1.800, 95% CI 1.086-2.984, p = 0.023) and heart failure (OR 2.410 95% CI 1.385-4.193, p = 0.002) independently predicted thrombotic events in this population. This study suggests that the P/F ratio is associated with thrombotic events by promoting a hypercoagulation state in patients hospitalized for COVID-19.

Effect of COVID-19 lockdown on refractive errors in Italian children aged 5-12 years: A multi-center retrospective study.

PURPOSE: to explore the potential consequences of the COVID-19 lockdown on the prevalence of myopia among Italian children aged 5-12 years. MATERIALS AND METHODS: retrospective multicenter study conducted in Italy. Population: children aged 5-12. Selection: random selection of children who received an eye exam between 2016 to 2021. Inclusion criteria: healthy children presenting for a routine eye exam. Exclusion criteria: presence of ocular comorbidities other than refractive error, such as blepharoptosis, media opacities, corneal or retinal dystrophies, strabismus, amblyopia, or concurrent therapy with atropine 0.01%. Outcome measure: age and spherical equivalent (SE) measured in diopters (D) in the right eye (RE) in cycloplegia. Statistical analysis: ANOVA test. RESULTS: total of 803 children. In the years prior to COVID-19, the mean SE ± SD of healthy age-school children was: 0.54 ± 1.49 D in 2016; 0.43 ± 1.84 D in 2017; 0.34 ± 1.41 D in 2018; 0.35 ± 1.75 D in 2019 (ANOVA, p = .659). In 2021, the mean SE changed to -0.08 ± 1.44 D (ANOVA, p = .005). Mean age was comparable in all groups (ANOVA, p = .307). The prevalence of myopes (SE ≤-0.5D) and hyperopes (SE ≥ 2D) was respectively 24.10% and 9.64% among children aged 60-96 months, and 63.86% and 6.02% among children aged 97-144 months. These values represent a statistically-significant increase in the number of myopes (Chi-square, p = .016) and decrease in the number of hyperopes (Chi-square, p = .001), as compared to previous years (.06 and.48 respectively). CONCLUSION: this retrospective study shows a statistically-significant decrease in the mean SE in children aged 5-12 in the year following the COVID-19 lockdown. The percentage of myopes has increased significantly, while the percentage of hyperopes has decreased. The lifestyle changes caused by the lockdown led children to spend more time on near-work activities and digital devices, and less time outdoors. These are known risk factors for the development and progression of myopia. Studies in different countries are encouraged.

Toll-Like Receptor 4-Dependent Platelet-Related Thrombosis in SARS-CoV-2 Infection.

BACKGROUND: SARS-CoV-2 is associated with an increased risk of venous and arterial thrombosis, but the underlying mechanism is still unclear. METHODS: We performed a cross-sectional analysis of platelet function in 25 SARS-CoV-2 and 10 healthy subjects by measuring Nox2 (NADPH oxidase 2)-derived oxidative stress and thromboxane B2, and investigated if administration of monoclonal antibodies against the S protein (Spike protein) of SARS-CoV-2 affects platelet activation. Furthermore, we investigated in vitro if the S protein of SARS-CoV-2 or plasma from SARS-CoV-2 enhanced platelet activation. RESULTS: Ex vivo studies showed enhanced platelet Nox2-derived oxidative stress and thromboxane B2 biosynthesis and under laminar flow platelet-dependent thrombus growth in SARS-CoV-2 compared with controls; both effects were lowered by Nox2 and TLR4 (Toll-like receptor 4) inhibitors. Two hours after administration of monoclonal antibodies, a significant inhibition of platelet activation was observed in patients with SARS-CoV-2 compared with untreated ones. In vitro study showed that S protein per se did not elicit platelet activation but amplified the platelet response to subthreshold concentrations of agonists and functionally interacted with platelet TLR4. A docking simulation analysis suggested that TLR4 binds to S protein via three receptor-binding domains; furthermore, immunoprecipitation and immunofluorescence showed S protein-TLR4 colocalization in platelets from SARS-CoV-2. Plasma from patients with SARS-CoV-2 enhanced platelet activation and Nox2-related oxidative stress, an effect blunted by TNF (tumor necrosis factor) α inhibitor; this effect was recapitulated by an in vitro study documenting that TNFα alone promoted platelet activation and amplified the platelet response to S protein via p47phox (phagocyte oxidase) upregulation. CONCLUSIONS: The study identifies 2 TLR4-dependent and independent pathways promoting platelet-dependent thrombus growth and suggests inhibition of TLR4. or p47phox as a tool to counteract thrombosis in SARS-CoV-2.

Asymptomatic and symptomatic deep venous thrombosis in hospitalized acutely ill medical patients: risk factors and therapeutic implications.

BACKGROUND: Acutely ill medical patients experience deep venous thrombosis (DVT) during the hospitalization, however the time course of DVT is still unclear. OBJECTIVES: To evaluate risk factors in acutely ill hospitalized medical patients for proximal asymptomatic DVT (ADVT) and symptomatic DVT (SDVT) at admission and discharge. PATIENTS/METHODS: In this prospective observational study, consecutive acutely ill medical patients (hospitalized mainly for acute medical disease as infections, neoplasm, anemia, heart failure) underwent compression ultrasonography (CUS) of proximal lower limb veins within 48 h from admission and at discharge to diagnose ADVT and SDVT. Covid-19 patients, anticoagulant therapy, surgical procedures, acute SDVT, and acute pulmonary embolism, were exclusion criteria. Biographical characteristics at hospitalization, D-Dimer (assessed by ELISA)) and DD-improve score. RESULTS: Of 2,100 patients (1002 females, 998 males, age 71 ± 16 years) 58 (2.7%) had proximal ADVT at admission. Logistic regression analysis showed that age, and active cancer were independently associated with ADVT at admission. The median length of hospitalization was 10 days [interquartile range: 6-15]. During the hospital stay, 6 patients (0.3%) with a negative CUS at admission experienced DVT (2 SDVT and 4 ADVT). In the subgroup of patients (n = 1118), in whom D-dimer was measured at admission, D-Dimer and IMPROVE-DD score were associated with ADVT at admission (n = 37) and with all DVT (n = 42) at discharge. ROC curve defined an IMPROVE-DD score of 2.5 as the optimal cut-off for discriminating patients with and without thrombotic events. CONCLUSIONS: We provide evidence of early development of ADVT in unselected acutely ill medical patients suggesting the need of investigating patients by CUS immediately after hospital admission (within 48 h). Advanced age, active cancer, known thrombophilia and increased IMPROVE-DD score may identify patients at risk. The benefit of anticoagulation needs to be investigated in patients with these specific risk factors and negative CUS at admission. TRIAL REGISTRATION: NCT03157843.

The ADA (Age-D-Dimer-Albumin) Score to Predict Thrombosis in SARS-CoV-2.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-related pneumonia is associated with venous and arterial thrombosis. Aim of the study was to find out a new score for predicting thrombosis in patients with SARS-CoV-2. METHODS: We included a cohort of 674 patients affected by SARS-CoV-2, not requiring intensive care units, and followed-up during the hospitalization until discharge. Routine analyses performed at in-hospital admission included also serum albumin and D-dimer while arterial and venous thromboses were the endpoints of the study. RESULTS: During the follow-up, 110 thrombotic events were registered; patients with thrombotic events were older and had lower albumin and higher D-dimer, compared with thrombotic event-free ones. On multivariable logistic regression with step-by-step procedure age, serum albumin, and D-dimer were independently associated with thrombotic events. The linear combination of age, D-dimer, and albumin allowed to build-up the ADA (age-D-dimer-albumin) score, whose area under the curve (AUC) was 0.752 (95% confidence interval [CI], 0.708-0.795). ADA score was internally validated by bootstrap sampling procedure giving an AUC of 0.752 (95% CI: 0.708-0.794). CONCLUSION: Combination of age, D-dimer, and albumin in the ADA score allows identifying SARS-CoV-2 patients at higher risk of thrombotic events.

Role of Serum E-Selectin as a Biomarker of Infection Severity in Coronavirus Disease 2019.

INTRODUCTION: E-selectin is a recognized marker of endothelial activation; however, its place in Coronavirus Disease 2019 (COVID-19) has not been fully explored. Aims of the study are to compare sE-selectin values among the Intensive Care Unit (ICU)-admitted and non-admitted, survived and non-survived patients and those with or without thrombosis. METHODS: A single-center study of patients with COVID-19 hospitalized at Policlinico Umberto I (Rome) from March to May 2020 was performed. Simple and multiple logistic regression models were developed. RESULTS: One hundred patients were included, with a median age (IQR) of 65 years (58-78). Twenty-nine (29%) were admitted to ICU, twenty-eight (28%) died and nineteen (19%) had a thrombotic event. The median value (IQR) of sE-selectin was 26.1 ng/mL (18.1-35). sE-selectin values did not differ between deceased and survivors (p = 0.06) and among patients with or without a thrombotic event (p = 0.22). Compared with patients who did not receive ICU treatments, patients requiring ICU care had higher levels of sE-selectin (36.6 vs. 24.1 ng/mL; p < 0.001). In the multiple logistic regression model, sE-selectin levels > 33 ng/mL, PaO2/FiO2 < 200 and PaO2/FiO2 200-300 were significantly associated with an increased risk of ICU admission. sE-selectin values significantly correlated with a neutrophil count (R = 0.32 (p = 0.001)) and the number of days from the symptoms onset to hospitalization (R = 0.28 (p = 0.004)). CONCLUSIONS: sE-selectin levels are predictive of ICU admission in COVID-19 patients. Since data on the relation between sE-selectin and COVID-19 are scarce, this study aims to contribute toward the comprehension of the pathogenic aspects of COVID-19 disease, giving a possible clinical marker able to predict its severity.

The Impact of the COVID-19 Epidemic During the Lockdown on Children With the Pediatric Acute-Onset Neuropsychiatric Syndrome (PANDAS/PANS): The Importance of Environmental Factors on Clinical Conditions.

Introduction: In March 2020, SARS-CoV-2 declared a pandemic by the World Health Organization. Restrictive isolation measures have also brought psychological distress to the pediatric population. Building on the syndrome's characteristics, the present study explored the impact of lockdown on the clinical course of young people with PANDAS/PANS. The initial hypothesis considered both the reduced exposure to viral agents and the strategies of the parents and other containment actions as protective factors against the worsening of symptoms. Methods: One hundred and eight children, adolescents, and young adults were recruited according to the multicenter PANDAS/PANS research program. Parents participated in a web-based survey. Results: contrary to our hypothesis, the study results show an increase in symptoms during the block in 71% of the sample. Psychometric analyzes allowed us to exclude a relationship between the main symptoms of PANDAS and the increase in symptoms or the presence of symptoms before the block and their increase over time. The increase in symptoms is best explained by the presence of sleep disturbances and emotional lability. The exacerbation also appears to be linked to the onset of new symptoms in children and adolescents with depressed moods and eating problems. Furthermore, irritability and oppositionality are significant predictors of acute exacerbation. Equally statistically significant is the factor linked to the effects of pandemic stress, such as the fear of contracting the virus. No significant associations for symptom reduction have been identified between parental strategies or other parent-initiated actions, but the study demonstrates that caregiver perceived efficacy on the strategies used can reduce the risk of exacerbation. Conclusion: This preliminary study highlights the importance of studying the causes of increased symptoms in children with PANDAS/PANS. Life events can exacerbate the clinical condition or generate new symptoms in young patients. In particular, environmental, family, and social changes in the course of clinical symptoms in PANDAS/PANS patients should be investigated. It highlights the importance of emotional and behavioral management, which can be improved by enhancing coping strategies in young people with PANDAS/PANS and their caregivers through a combination treatment in which CBT and PMT are included, in line with guidelines. Limits: An experimental proxy-report questionnaire not yet standardized and validated on the PANS/PANDAS pediatric clinical sample was used for the exploratory study. There is also a small sample size (N = 108) and the absence of a control group (pre-lockdown or children without PANDAS/PANS). It would be interesting to evaluate the exact long-term dimensions to see the course of symptoms after covid and conduct a new study focusing on the impact of stressful events on the clinical course of the syndrome.

COVID-19-Related Anosmia: The Olfactory Pathway Hypothesis and Early Intervention.

Anosmia is a well-described symptom of Corona Virus Disease 2019 (COVID-19). Several respiratory viruses are able to cause post-viral olfactory dysfunction, suggesting a sensorineural damage. Since the olfactory bulb is considered an immunological organ contributing to prevent the invasion of viruses, it could have a role in host defense. The inflammatory products locally released in COVID-19, leading to a local damage and causing olfactory loss, simultaneously may interfere with the viral spread into the central nervous system. In this context, olfactory receptors could play a role as an alternative way of SARS-CoV-2 entry into cells locally, in the central nervous system, and systemically. Differences in olfactory bulb due to sex and age may contribute to clarify the different susceptibility to infection and understand the role of age in transmission and disease severity. Finally, evaluation of the degree of functional impairment (grading), central/peripheral anosmia (localization), and the temporal course (evolution) may be useful tools to counteract COVID-19.

Features of severe COVID-19: A systematic review and meta-analysis.

BACKGROUND: To systematically review clinical and biochemical characteristics associated with the severity of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related disease (COVID-19). MATERIALS AND METHODS: Systematic review of observational studies from PubMed, ISI Web of Science, SCOPUS and Cochrane databases including people affected by COVID-19 and reporting data according to the severity of the disease. Data were combined with odds ratio (OR) and metanalysed. Severe COVID-19 was defined by acute respiratory distress syndrome, intensive care unit admission and death. RESULTS: We included 12 studies with 2794 patients, of whom 596 (21.33%) had severe disease. A slightly higher age was found in severe vs non-severe disease. We found that prevalent cerebrovascular disease (odds ratio [OR] 3.66, 95% confidence interval [CI] 1.73-7.72), chronic obstructive pulmonary disease (OR: 2.39, 95% CI 1.10-5.19), prevalent cardiovascular disease (OR: 2.84, 95% CI 1.59-5.10), diabetes (OR: 2.78, 95% CI 2.09-3.72), hypertension (OR: 2.24, 95% CI 1.63-3.08), smoking (OR: 1.54, 95% CI 1.07-2.22) and male sex (OR: 1.22, 95% CI 1.01-1.49) were associated with severe disease. Furthermore, increased procalcitonin (OR: 8.21, 95% CI 4.48-15.07), increased D-Dimer (OR: 5.67, 95% CI 1.45-22.16) and thrombocytopenia (OR: 3.61, 95% CI 2.62-4.97) predicted severe infection. CONCLUSION: Characteristics associated with the severity of SARS-CoV-2 infection may allow an early identification and management of patients with poor outcomes.