This study shows that in SLE patients, aPL positivity is associated with an ongoing prothrombotic state only in the presence of endothelial perturbation. Our findings also suggest that aPLs and TNF-alpha might cooperate in inducing endothelial perturbation.

Background-Previousstudies have shown that cirrhotic patients produce increased amounts of thrombin but the underlying mechanism is still unknown. Aims-To analyse the relation between the rate of thrombin generation and monocyte expression of tissue factor (TF) in cirrhosis. Patients-Thirty three cirrhotic patients classified as having low (n=7), moderate (n=17), or severe (n=9) liver failure according to Child-Pugh criteria. Methods-Prothrombin fragment F1+2, monocyte TF activity and antigen, and endotoxaemia were measured in all patients. Polymerase chain reaction (PCR) analysis of TF mRNA was performed in monocytes of five cirrhotic patients. Results-Prothrombin fragment F1+2 was higher in cirrhotic patients than in controls (p<0.0001). Monocytes from cirrhotic patients had higher TF activity and antigen than those from controls (p<0.001) with a progressive increase from low to severe liver failure. Monocyte expression of TF was significantly correlated with plasma levels of F1+2 (TF activity: r=0.98, p<0.0001; TF antigen: r=0.95, p<0.0001) and with endotoxaemia (TF activity: r=0.94, p<0.0001; TF antigen: r=0.91, p<0.0001). PCR analysis of TF mRNA showed TF expression only in three patients with endotoxaemia (more than 15 pg/ml). Conclusions-Cirrhotic patients have enhanced expression of TF which could be responsible for clotting activation, suggesting that endotoxaemia might play a pivotal role. (Gut 1998;43:428-432)

Summary. In a first study, we performed a cross-sectional analysis of urinary excretion of isoprostanes, IPF 2a-III and VI , and monocyte tissue factor (TF) antigen and activity between 11 antiphospholipid (APL) antibody-positive patients and 13 APL negative subjects. In a second study, 11 APL positive patients were randomly supplemented either with (n ¼ 6) or without (n ¼ 5) antioxidants (vitamin E at 900 IU day À1 , vitamin C at 2000 mg day À1 ) for 6 weeks. In a third study, TF and superoxide anion were measured in human monocytes incubated with antib 2 glycoprotein 1 (b 2 GP 1 ) or control IgG, either with or without vitamin E. APL-positive patients had higher values of isoprostanes (P < 0.05) and monocyte TF antigen (P ¼ 0.001) and activity (P ¼ 0.0001) than APL-negative subjects. Only in APL positive patients did monocyte TF antigen correlate significantly with IPF 2a-III (rho 0.79; P < 0.003) and IPF 2a-VI (rho ¼ 0.87; P < 0.0001). In patients who received antioxidant supplementation, we found a significant decrease of isoprostanes (P < 0.05) and monocyte TF antigen (P < 0.01) and activity (P < 0.007). In vitro experiments demonstrated that anti-b 2 GP 1 antibodies dose-dependently enhanced the monocyte production of the superoxide anion and TF, which were significantly inhibited by vitamin E. This study demonstrates that in APL-positive patients, oxidative stress contributes to activate the clotting system via over-expression of monocyte TF. We suggest that anti-b 2 GP 1 antibodies could play a pivotal role by enhancing the monocyte production of oxygen free radicals.

Chest computed tomography (CT) has been frequently used to evaluate patients with potential COVID-19 infection. However, this may be particularly risky for pediatric patients due to high doses of ionizing radiation. We sought to evaluate COVID-19 imaging options in pediatric patients based on published literature. We performed an exhaustive literature review focusing on COVID-19 imaing of pediatric patients. Researcher used “COVID-19”, “SARS-CoV2”, “coronavirus”, “2019-nCoV”, “Wuhan virus”, “lung ultrasound (LUS)”, “sonography”, “lung HRCT”, “children”, “childhood” and “newborn” as search terms to query online databases including: US National Library of Medicine (PubMed), Medical Subject Headings (MeSH), Excerpta Medica dataBASE (EMBASE), LitCovid, WHO COVID-19 database and Medical Literature Analysis and Retrieval System Online (Medline Bireme). Articles meeting inclusion criteria were included in the analysis and review. We identified only 7 studies using LUS for diagnosing SARS-CoV2 infection in children. The studies evaluated small numbers of patients and only 6% had severe or critical illness associated with COVID-19. LUS showed the presence of: B-lines in 50% of patients, sub-pleural consolidation in 43.18%, pleural irregularities in 34.09%, coalescent B-lines and white lung in 25%, pleural effusion in 6.82% and thickening of pleural line in 4.55% of newborn/children. Researhers found 117 studies describing CXR or chest CT use in pediatric patients with COVID-19. The proportion of severely or critically ill was similar to the LUS study population. Our review indicates that LUS utilization should be encouraged in pediatric patients, which is at highest risk for complications for medical ionizing radiation. Increased use of LUS may be of particularly high impact in low resourced areas where access to chest CT may be limited.

, infection by the new SARS-CoV2 spread fast all over the world. It can present as severe respiratory distress in the elderly or a vasculitis in a child, most of whom are typically completely asymptomatic. This makes infection detection based on clinical grounds exceedingly difficult. Lung ultrasound has become an important tool in diagnosis and followup of patient with COVID-19 infection.Here we review available, up to date literature on ultrasound use for COVID-19 suspected pediatric patients and contrast it to published findings in adult patients.