A b s t r a c t EDTA-dependent pseudothrombocytopenia (PTCP) consists of an inappropriate low platelet count caused by autoantibodies present in the serumIn EDTA-dependent pseudothrombocytopenia (PTCP), autoantibodies present in serum samples react with platelets in blood anticoagulated with EDTA causing platelet agglutination and an incorrect low platelet count. The minimal EDTA concentration (0.3-mmol/L of Na,-EDTA) required to produce platelet agglutination is much lower than that needed to prevent clotting and is independent from the cationic composition of the EDTA solution used as anticoagulant. Platelet agglutination also has been reported to occur in blood anticoagulated with citrate or heparin and is time-and temperature-dependent. 1 The majority of antibodies isolated in EDTA-dependent PTCP act as cold agglutinins with a heat range from 4°C to 20°C and are of the IgG or IgM class. Time course studies showed that platelet agglutination in EDTA anticoagulated blood generally occurs within a few minutes and becomes more conspicuous when blood samples are kept at room temperature; at 37°C, agglutination is abolished or, in a minority of cases, less evident. In patients with PTCP with EDTA and citrate-dependent platelet clumping, agglutinins are reactive at room temperature and at 37°C and belong mainly to the IgM class. Although some indirect observations suggest that these antibodies might recognize the platelet membrane glycoprotein (GP) complex Ilb/IIIa,'^ only a few reports directly demonstrate the antigenic determinant recognized by these antibodies: by means of crossed Immunoelectrophoresis, van Vliet et al 5 observed an IgM antibody directed against the membrane GP lib, and De Caterina et al 6 found an antibody directed against a protein with a 78-kd molecular weight.To assess any potential role of PTCP-associated IgG antibodies, we assayed plasma levels of glycocalicin (GC), which is the external carbohydrate-rich hydrophilic fragment of the cc-subunit of GP lb 7 ; it is readily cleaved from GP lib by 1 7 8

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We report here the first blood donation positive for West Nile virus (WNV) by nucleic acid amplification testing collected in northeastern Italy in July 2012. Partial sequencing of the WNV RNA demonstrated identity with a WNV lineage 1a genome identified in the same area in 2011 and divergence from the strain responsible for the outbreak in northern Italy in 2008-09. These data indicate that WNV activity in northern Italy is occurring earlier than expected and that different WNV strains are circulating.

Objectives and background Convalescent plasma (CP) has been used worldwide to contrast SARS-CoV-2 infection. Since April 2020, it has also been used in the treatment of patients with COVID-19 in the Veneto region (Italy), along with all the other available drugs and therapeutic tools. Here we report data analysis and clinical results in 1,517 COVID-19 inpatients treated with CP containing high-titre neutralizing anti-SARS-CoV-2 antibodies (CCP). Mortality after 30 days of hospitalization has been considered primary outcome, by comparing patients treated with CCP vs all COVID-19 patients admitted to hospitals of the Veneto region in a one-year period (from April 2020 to April 2021). Patients and methods Adult inpatients with a severe form of COVID-19 have been enrolled, with at least one of the following inclusion criteria: 1) tachypnea with respiratory rate (RR) ≥ 30 breaths/min; 2) oxygen saturation (SpO 2 ) ≤ 93% at rest and in room air; 3) partial pressure of oxygen (PaO 2 )/fraction of inspired oxygen (FiO 2 ) ≤ 200 mmHg, 4) radiological picture and/or chest CT scan showing signs of interstitial disease and/or rapid progression of lung involvement. Patients received a maximum of three therapeutic fractions (TFs) of CCP with a neutralizing antibody titre of ≥ 1:160, administered over a period of 3-5 days. If TFs of CCP with titre ≥ 1:160 were unavailable, 2 with antibody titre of ≥ 1:80 have been administered. Results Of the 1,517 patients treated with CCP, 209 deceased at the 30-day follow-up (14%). Death was significantly associated with an older age (p<0.001), a longer time of hospitalization before CCP infusion (p<0.001), a greater number of inclusion criteria (p<0.001) and associated comorbidities (p<0.001). Conditions significantly associated with an increased frequency of death were PaO 2 /FiO 2 ≤ 200 (p<0.001) and tachypnea with RR>30 (p<0.05) at entry, concurrent arterial hypertension (p<0.001), cardiovascular disease (p<0.001), chronic kidney disease (p<0.001), dyslipidemia (p<0.05) and cancer (p<0.05). Moreover, factors leading to an unfavorable prognosis were a life-threatening disease (p<0.001), admission to Intensive Care Unit (p<0.001), high flow oxygen therapy or mechanical ventilation (p<0.05) and a chest X-ray showing consolidation area (p<0.001). By analyzing the regional report of hospitalized patients, a comparison of mortality by age group, with respect to our series of patients treated with CCP, has been made. Mortality was altogether lower in patients treated with CCP (14% v. 25%), especially in the group of the elderly patients (23% vs 40%,), with a strong significance (p<0.001). As regards the safety of CCP administration, 16 adverse events were recorded out of a total of 3,937 transfused TFs (0,4%). Conclusions To overcome the difficulties of setti...