NETosis in Acute Thrombotic Disorders.

The release of extracellular traps by neutrophils (NETs) represents a novel active mechanism of cell death that has been recently implicated in the pathogenesis of thrombotic disorders. The aim of this study was to investigate the generation of NETs in different groups of patients with acute thrombotic events (ATEs) and to establish whether NETs markers can predict the risk of new cardiovascular events. We performed a case-control study of patients with ATE, including acute coronary syndrome (n = 60), cerebrovascular accident (n = 50), and venous thromboembolism (n = 55). Control subjects (n = 70) were identified among patients admitted for acute chest pain and in which a diagnosis of ATE was excluded. Serum levels of NET markers and neutrophil activation, such as myeloperoxidase (MPO)-DNA complexes, neutrophil gelatinase-associated lipocalin, polymorphonuclear neutrophil elastase, lactoferrin, and MPO, were measured in each patient. We found that circulating levels of MPO-DNA complexes were significantly increased in patients with ATE (p < 0.001) compared with controls and that this association remained significant even after fully adjustment for traditional risk factors (p = 0.001). A receiver operating characteristics analysis of circulating MPO-DNA complexes in discriminating between controls and patients with ATE showed a significant area under the curve of 0.76 (95% confidence interval: 0.69-0.82). After a median follow-up of 40.7 (± 13.8) months, 24 out of the 165 patients with ATE presented a new cardiovascular event and 18 patients died. None of the markers under investigation influenced survival or the incidence of new cardiovascular events. In conclusion, we found that increase of markers of NETosis can be observed in acute thrombotic conditions, occurring both on the arterial and venous site. Nevertheless, the level of neutrophil markers measured during the ATE is not predictive of future risk of mortality and cardiovascular events.

Impact of Hypogammaglobulinemia on the Course of COVID-19 in a Non-Intensive Care Setting: A Single-Center Retrospective Cohort Study.

Background: Severity and mortality of COVID-19 largely depends on the ability of the immune system to clear the virus. Among various comorbidities potentially impacting on this process, the weight and the consequences of an antibody deficiency have not yet been clarified. Methods: We used serum protein electrophoresis to screen for hypogammaglobulinemia in a cohort of consecutive adult patients with COVID-19 pneumonia, hospitalized in non-intensive care setting between December 2020 and January 2021. The disease severity, measured by a validated score and by the need for semi intensive (sICU) or intensive care unit (ICU) admission, and the 30-day mortality was compared between patients presenting hypogammaglobulinemia (HYPO) and without hypogammaglobulinemia (no-HYPO). Demographics, comorbidities, COVID-19 specific treatment during the hospital stay, disease duration, complications and laboratory parameters were also evaluated in both groups. Results: We enrolled 374 patients, of which 39 represented the HYPO cohort (10.4%). In 10/39 the condition was previously neglected, while in the other 29/39 hematologic malignancies were common (61.5%); 2/39 were on regular immunoglobulin replacement therapy (IgRT). Patients belonging to the HYPO group more frequently developed a severe COVID-19 and more often required sICU/ICU admission than no-HYPO patients. IgRT were administered in 8/39 during hospitalization; none of them died or needed sICU/ICU. Among HYPO cohort, we observed a significantly higher prevalence of neoplastic affections, of active oncologic treatment and bronchiectasis, together with higher prevalence of viral and bacterial superinfections, mechanical ventilation, convalescent plasma and SARS-CoV-2 monoclonal antibodies administration during hospital stay, and longer disease duration. Multivariate logistic regression analysis and Cox proportional hazard regression confirmed the impact of hypogammaglobulinemia on the COVID-19 severity and the probability of sICU/ICU admission. The analysis of the mortality rate in the whole cohort showed no significant difference between HYPO and no-HYPO. Conclusions: Hypogammaglobulinemia, regardless of its cause, in COVID-19 patients hospitalized in a non-intensive care setting was associated to a more severe disease course and more frequent admission to s-ICU/ICU, particularly in absence of IgRT. Our findings emphasize the add-value of routine serum protein electrophoresis evaluation in patients admitted with COVID-19 to support clinicians in patient care and to consider IgRT initiation during hospitalization.

Comparison between Dexamethasone and Methylprednisolone Therapy in Patients with COVID-19 Pneumonia Admitted to Non-Intensive Medical Units.

(1) Background: Data on different steroid compounds for the treatment of hospitalized COVID-19 (coronavirus disease 2019) patients are still limited. The aim of this study was to compare COVID-19 patients admitted to non-intensive units and treated with methylprednisolone or dexamethasone. (2) Methods: This was a single-center retrospective study that included consecutive patients with COVID-19 hospitalized in medical wards during the second wave of the pandemic. Thirty-day mortality and the need for intensive or semi-intensive care were the main clinical outcomes analyzed in patients receiving methylprednisolone (60 mg/day) compared with dexamethasone (6 mg/day). Secondary outcomes included complication rates, length of hospital stay, and time to viral clearance. (3) Results: Two-hundred-forty-six patients were included in the analysis, 110 treated with dexamethasone and 136 with methylprednisolone. No statistically significant differences were found between the two groups of patients regarding 30-day mortality (OR 1.35, CI95% 0.71-2.56, p = 0.351) and the need for intensive or semi-intensive care (OR 1.94, CI95% 0.81-4.66, p = 0.136). The complication rates, length of hospital stay, and time to viral clearance did not significantly differ between the two groups. (4) Conclusions: In patients hospitalized for COVID-19 in non-intensive units, the choice of different steroid compounds, such as dexamethasone or methylprednisolone, did not affect the main clinical outcomes.

RANKL Expression Is Increased in Circulating Mononuclear Cells of Patients with Calcific Aortic Stenosis.

We aimed to investigate whether the expression of the OPG/RANK/RANKL triad in peripheral blood mononuclear cells (PBMC) and circulating levels of markers of ectopic mineralization (OPG, FGF-23, PPi) are modified in patients with calcific aortic valve disease (CAVD). We found that patients affected by CAVD (n = 50) had significantly higher circulating levels of OPG as compared to control individuals (p = 0.003). No differences between the two groups were found in FGF-23 and PPi levels. RANKL expression was higher in the PBMC from CAVD patients (p = 0.018) and was directly correlated with the amount of valve calcification (p = 0.032). In vitro studies showed that treatment of valve interstitial cells (VIC) with RANKL plus phosphate was followed by increase in matrix mineralization (p = 0.001). In conclusion, RANKL expression is increased in PBMC of patients with CAVD, is directly correlated with the degree of valve calcification, and promotes pro-calcific differentiation of VIC.

Atorvastatin Reduces Circulating Osteoprogenitor Cells and T-Cell RANKL Expression in Osteoporotic Women: Implications for the Bone-Vascular Axis.

AIM: Circulating osteoprogenitors and receptor activator of nuclear factor kappa-B ligand (RANKL) expression in immune cells have been implicated in the pathogenesis of osteoporosis and vascular calcification. The role played by statin therapy in the bone-vascular axis is unknown. METHODS: Twenty naïve postmenopausal osteoporotic hypercholesterolemic women were treated with Atorvastatin 40 mg/day for 3 months. Gene expression analysis was performed to assess modification in osteoprotegerin (OPG)/RANK/RANKL expression in isolated T cells and monocytes. A flow cytometry analysis was used to study changes in the levels of circulating osteoprogenitor cells. RESULTS: After 3 months of treatment, Atorvastatin significantly reduced total cholesterol and LDL-C, without affecting HDL-C and triglycerides. Among circulating bone and phosphocalcium homeostasis markers, we found a significant increase in OPG levels (P < 0.01) and a modest reduction in osteocalcin (OCN) (P < 0.05). We also observed a significant reduction in RANKL expression in T cells (P < 0.05). No differences were found in the expression of RANK in T cells and RANKL and RANK in monocytes. OPG expression was low in both immune cell types and was not affected by the treatment. As for circulating osteoprogenitors, we found a significant reduction of CD34(+) BAP(+) (P < 0.05) and CD34(+) OCN(+) BAP(+) (P < 0.05) cells. In vitro studies showed that Atorvastatin reduced RANKL expression in activated human T-lymphoblastoid cells (Jurkat cell line). CONCLUSIONS: Three-month Atorvastatin treatment leads to a reduction in circulating osteoprogenitor cells and RANKL expression in T cells, as well as increase in OPG serum levels. These data suggest that statins could have protective effects in the bone-vascular axis.

An Unusual Case of Fibromuscular Dysplasia with Bilateral Renal Macroaneurysms: Three-year Outcome After Endovascular Treatment.

Fibromuscular dysplasia (FMD) is an idiopathic, segmental, non-inflammatory and non-atherosclerotic disease that affects arterial walls, leading to stenosis of small and medium-sized arteries. FMD mostly involves renal and intracranial arteries and only in few patients is associated with macroaneurysms (RAAs). We present the case of a 45-years old woman with recent history of grade 2 hypertension that suffered of subarachnoid haemorrhage due to rupture of a basilar artery aneurysm. The cerebral aneurysm was immediately treated by coil embolization and an abdominal angio-CT scan was performed to investigate the presence of renovascular hypertension. The exam showed the presence of FMD of the renal arteries associated with presence of bilateral RAAs. Due to the high risk of rupture, the bigger aneurysm (2,5 cm diameter) present on the left artery was immediately treated by coil embolization. The fusiform aneurysm, present on the right renal artery, was instead treated one year later by using two flow diverter stents. After three years, an angiographic study showed that both cerebral and renal aneurysms were excluded from the blood flow without evidence of arterial restenosis.

Low CD34(+) cells, high neutrophils and the metabolic syndrome are associated with an increased risk of venous thromboembolism.

The relationship between MetS (metabolic syndrome), levels of circulating progenitor/immune cells and the risk of VTE (venous thromboembolism) has not yet been investigated. We studied 240 patients with previous VTE and 240 controls. The presence of MetS was identified according to NCEP ATP III guidelines and flow cytometry was used to quantify circulating CD34(+) cells. VTE patients showed higher BMI (body mass index), waist circumference, triacylglycerol (triglyceride) levels, blood glucose, hs-CRP (high-sensitivity C-reactive protein) and lower HDL-C (high-density lipoprotein cholesterol) levels. The prevalence of MetS was significantly higher in VTE (38.3%) than in control individuals (21.3%) with an adjusted OR (odds ratio) for VTE of 1.96 (P=0.002). VTE patients had higher circulating neutrophils (P<0.0001), while the CD34(+) cell count was significantly lower among patients with unprovoked VTE compared with both provoked VTE (P=0.004) and controls (P=0.003). Subjects were also grouped according to the presence/absence of MetS (MetS(+) or MetS(-)) and the level (high/low) of both CD34(+) cells and neutrophils. Very high adjusted ORs for VTE were observed among neutrophils_high/MetS(+) (OR, 3.58; P<0.0001) and CD34(+)_low/MetS(+) (OR, 3.98; P<0.0001) subjects as compared with the neutrophils_low/MetS(-) and CD34(+)_high/MetS(-) groups respectively. In conclusion, low CD34(+) blood cell count and high circulating neutrophils interplay with MetS in raising the risk for venous thromboembolic events.