Risk of SARS-CoV-2 infection and severe COVID-19 in hematological patients who received or not pre-exposure prophylaxis with tixagevimab/cilgavimab: a target trial emulation.

We emulated a hypothetical target trial in which hematological subjects cared at the University Hospital of Pisa (Italy) received or not SARS-CoV-2 prophylaxis with tixagevimab/cilgavimab. Subjects who received prophylaxis (cases) were compared to those who did not (controls). The main outcome was SARS-CoV-2 infection in the subsequent 6 months.

Efficacy and Safety of Nirmatrelvir/Ritonavir, Molnupiravir, and Remdesivir in a Real-World Cohort of Outpatients with COVID-19 at High Risk of Progression: The PISA Outpatient Clinic Experience.

Introduction: Different antivirals are available for the treatment of outpatients with COVID-19. Our aim was to describe a real-world experience of outpatient management of COVID-19 subjects at high risk of progression.

Methods: This prospective observational study conducted in the University Hospital of Pisa (January 2022-July 2022) included consecutive COVID-19 outpatients with at least one risk factor for disease progression.

Disease correlates and clinical relevance of hereditary α-tryptasemia in patients with systemic mastocytosis.

Background: Systemic mastocytosis (SM) encompasses a heterogeneous group of clonal disorders characterized by abnormal expansion of mast cells (MCs). Beyond KIT and other genes recurrently mutated in myeloid neoplasms, several genetic variants have been described as predisposing to the development of the disease and influencing its clinical phenotype. Increased copy number variants of the TPSAB1 gene were identified as a cause of nonclonal elevated tryptasemia and defined as hereditary α-tryptasemia (HαT).

Anti-severe acute respiratory syndrome coronavirus-2 adenoviral-vector vaccines trigger subclinical antiplatelet autoimmunity and increase of soluble platelet activation markers.

To slow down the coronavirus disease 2019 (COVID-19) pandemic an unequalled vaccination campaign was initiated. Despite proven efficacy and safety, a rare but potentially fatal complication of adenoviral-vector vaccines, called vaccine-induced immune thrombotic thrombocytopenia (VITT), has emerged the pathogenesis of which seems to be related to the development of platelet-activating anti-platelet factor 4 (PF4) antibodies. While a few studies have evaluated the incidence of anti-PF4 positivity in anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine recipients, to date no studies have assessed whether an antiplatelet immunological response develops and if this associates with platelet and blood clotting activation.