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Objective: It is unclear why activated platelets and platelet‐derived microparticles (MPs) accumulate in the blood of patients with systemic sclerosis (SSc). This study was undertaken to investigate whether defective phagocytosis might contribute to MP accumulation in the blood of patients with SSc. Methods: Blood samples were obtained from a total of 81 subjects, including 25 patients with SSc and 26 patients with stable coronary artery disease (CAD). Thirty sex‐ and age‐matched healthy volunteers served as controls. Studies were also conducted in NSG mice, in which the tail vein of the mice was injected with MPs, and samples of the lung parenchyma were obtained for analysis of the pulmonary microvasculature. Tissue samples from human subjects and from mice were assessed by flow cytometry and immunochemical analyses for determination of platelet–neutrophil interactions, phagocytosis, levels and distribution of P‐selectin, P‐selectin glycoprotein ligand 1 (PSGL‐1), and HMGB1 on platelets and MPs, and concentration of byproducts of neutrophil extracellular trap (NET) generation/catabolism. Results: Activated P‐selectin+ platelets and platelet‐derived HMGB1+ MPs accumulated in the blood of SSc patients but not in the blood of healthy controls. Patients with CAD, a vasculopathy independent of systemic inflammation, had fewer P‐selectin+ platelets and a negligible number of MPs. The expression of the receptor for P‐selectin, PSGL‐1, in neutrophils from SSc patients was significantly decreased, raising the possibility that phagocytes in SSc do not recognize activated platelets, leading to a failure of phagocytosis and continued neutrophil release of MPs. As evidence of this process, activated platelets were not detected in the neutrophils from SSc patients, whereas they were consistently present in the neutrophils from patients with CAD. HMGB1+ MPs elicited generation of NETs, which were only detected in the plasma of SSc patients. In mice, P‐selectin–PSGL‐1 interaction resulted in platelet phagocytosis in vitro and influenced the ability of MPs to elicit NETs, endothelial activation, and migration of leukocytes through the pulmonary microvasculature. Conclusion: The clearance of activated platelets via PSGL‐1 limits the undesirable effects of MP‐elicited neutrophil activation. This balance is disrupted in patients with SSc. Its reconstitution might curb vascular inflammation and prevent fibrosis. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the correlation of anti-β2-glycoprotein I (anti-β2GPI) and anticardiolipin antibodies (aCL) with macrovascular disease in systemic sclerosis (SSc) patients. It evaluates 75 SSc patients with a history of ischemic digital loss and 75 matched SSc controls. Results show that anti-β2GPI positivity is associated with macrovascular disease in SSc patients, including digital loss and pulmonary arterial hypertension.

Objective: The use of angiotensin II in invasively ventilated patients with coronavirus disease 2019 (COVID-19) is controversial. Its effect on organ function is unknown. Design: Prospective observational study. Setting: Intensive care unit (ICU) of a tertiary academic hospital in Milan, Italy. Participants: Adult patients receiving mechanical ventilation due to COVID-19. Interventions: Use angiotensin II either as rescue vasopressor agent or as low dose vasopressor support. Main outcome measures: Patients treated before angiotensin II was available or treated in an adjacent COVID-19 ICU served as controls. For data analysis, we applied Bayesian modelling as appropriate. We assessed the effects of angiotensin II on organ function. Results: We compared 46 patients receiving angiotensin II therapy with 53 controls. Compared with controls, angiotensin II increased the mean arterial pressure (median difference, 9.05 mmHg; 95% CI, 1.87-16.22; P = 0.013) and the PaO 2 /FiO 2 ratio (median difference, 23.17; 95% CI, 3.46-42.88; P = 0.021), and decreased the odds ratio (OR) of liver dysfunction (OR, 0.32; 95% CI, 0.09-0.94). However, angiotensin II had no effect on lactate, urinary output, serum creatinine, C-reactive protein, platelet count, or thromboembolic complications. In patients with abnormal baseline serum creatinine, Bayesian modelling showed that angiotensin II carried a 95.7% probability of reducing the use of renal replacement therapy (RRT). Conclusions: In ventilated patients with COVID-19, angiotensin II therapy increased blood pressure and PaO 2 /FiO 2 ratios, decreased the OR of liver dysfunction, and appeared to decrease the risk of RRT use in patients with abnormal baseline serum creatinine. However, all of these findings are hypothesis-generating only. Trial registration: ClinicalTrials.gov NCT04318366., Competing Interests: No relevant disclosures., (© 2021 College of Intensive Care Medicine of Australia and New Zealand.)

Background: In Europe, Italy and Lombardy, in autumn 2020, there was a steep increase in reported cases due to the second epidemic wave of SARS-Cov-2 infection. We aimed to evaluate the appropriateness of COVID-19 patients' admissions to the ED of the San Raffaele Hospital., Methods: We compared data between the inter-wave period (IWP, from 1st to 30th September) and the second wave period (WP, 1st October to 15th November) focusing on the ED presentation, discharge priority colour code and outcomes., Results: Out of 977 admissions with a SARS-Cov-2 positive swab, 6% were in the IWP and 94% in the WP. Red, yellow and white code increased (these latter from 1.8% to 5.4%) as well as self-presented in yellow and white code. Discharges home increased from 1.8% to 5.4%, while hospitalizations decreased from 63% to 51%., Discussion: We found a rise in white codes (among self-presented patients), indicating inappropriateness of admissions. The increase in discharges suggests that several patients did not require hospitalization., Conclusions: The pandemic brought out the fundamental role of primary care to manage patients with low-intensity needs. The important increase in ED admissions of COVID-19 patients caused a reduction of NO-COVID-19 patients, with possible inadequate treatment.

Objective: Systemic sclerosis (SSc; scleroderma) is characterized by a unique widespread vascular involvement that can lead to severe digital ischemia, pulmonary arterial hypertension (PAH), or other organ dysfunction. Microthrombotic events and procoagulation factors such as anti-beta2-glycoprotein I (anti-beta2GPI) or anticardiolipin antibodies (aCL) may be implicated in the development of these manifestations. This study was undertaken to investigate whether anti-beta2GPI and aCL are correlated with macrovascular disease, including ischemic digital loss and PAH, in SSc patients., Methods: Seventy-five SSc patients with a history of ischemic digital loss and 75 matched SSc controls were evaluated. Anticentromere antibodies (ACAs), anti-beta2GPI, and aCL were measured, and clinical associations were determined using conditional and simple logistic regression models., Results: Positivity for anti-beta2GPI was significantly more frequent in SSc patients with digital loss than in patients without digital loss (P=0.017), with the IgA isotype of anti-beta2GPI showing the strongest association (odds ratio [OR] 4.0). There was no significant difference in aCL frequency between patients with digital loss and control patients. After adjustment for demographic characteristics, disease type, smoking, and ACA, anti-beta2GPI positivity was significantly associated with active digital ischemia (OR 9.4), echocardiographically evident PAH (OR 4.8), and mortality (OR 2.9). ACA positivity was associated with history of digital loss (OR 3.28), but not with PAH or mortality. History of digital loss was strongly associated with increased mortality (OR 12.5)., Conclusion: Anti-beta2GPI is significantly associated with macrovascular disease in SSc and independently predicts mortality. It is unclear whether it has a pathogenetic role or simply reveals the presence of underlying endothelial injury. The use of anti-beta2GPI as a biomarker of vascular disease in SSc should be further explored.