Evaluation of Antibody Kinetics Following COVID-19 Vaccination in Greek SARS-CoV-2 Infected and Naïve Healthcare Workers.

We investigated the antibody kinetics after vaccination against COVID-19 in healthcare workers of a Greek tertiary hospital. Eight hundred and three subjects were included, of whom 758 (94.4%) received the BNT162b2 vaccine (Pfizer-BioNTech), eight (1%) mRNA-1273 (Moderna), 14 (1.7%) ChAdOx1 (Oxford-AstraZeneca) and 23 (2.9%) Ad26.COV2.S (Janssen). Before the second dose, at 2, 6 and 9 months after the second dose and at 2 and 6 months after the third dose, anti-spike IgG were quantified by the chemiluminescence microparticle immunoassay method. One hundred subjects were infected before vaccination (group A), 335 were infected after receiving at least one vaccine dose (group B), while 368 had never been infected (group C). Group A presented a greater number of hospitalizations and reinfections compared to group B (p < 0.05). By multivariate analysis, younger age was associated with an increased risk of reinfection (odds ratio: 0.956, p = 0.004). All subjects showed the highest antibody titers at 2 months after the second and third dose. Group A showed higher antibody titers pre-second dose, which remained elevated 6 months post-second dose compared to groups B and C (p < 0.05). Pre-vaccine infection leads to rapid development of high antibody titer and a slower decline. Vaccination is associated with fewer hospitalizations and fewer reinfections.

Thrombotic risk factors and liver histologic lesions in non-alcoholic fatty liver disease.

BACKGROUND/AIMS: The pathogenetic mechanisms of development of non-alcoholic steatohepatitis (NASH) and fibrosis are not clear, although thrombosis of small intrahepatic veins has been suggested to trigger liver tissue remodelling and thrombotic risk factors have been associated with more advanced fibrosis in chronic viral hepatitis (CVH). We evaluated the prevalence of thrombotic risk factors (RFs) in non-alcoholic fatty liver disease (NAFLD) and their possible association with fatty liver or NASH. METHODS: We included 60 patients with histologically documented NAFLD and a historical cohort of 90 patients with chronic hepatitis B (n=39) or C (n=51). Thrombophilic factors were evaluated on the day of the liver biopsy. RESULTS: One or more thrombotic RFs were detected in 37% of NAFLD patients, and >or= 2 RFs were detected in 12% of NAFLD patients, being less frequently present than in CVH patients (37% and 68%, respectively; P