Monitoring of Patients with Autoimmune Cytopenias during Sars-Cov-2 Vaccination Campaign: The Experience of a Reference Center

ABSTRACT

[Formula presented] SARS-CoV-2 infection and vaccination have raised concern in immune mediated diseases, including autoimmune cytopenias (AIC, i.e. autoimmune hemolytic anemia, AIHA;autoimmune thrombocytopenia, ITP;autoimmune neutropenia, AIN;aplastic anemia, AA;and their combination, termed Evans syndrome, ES). The latter are highly heterogeneous conditions with variable severity and a clinical course marked by several relapses often triggered by immune-activating events (infections, traumas, surgery, etc.) including vaccines. Some reports of ITP and AIHA post-SARS-CoV-2 vaccines have been described but no population studies have been conducted in AIC patients. Here we systematically studied a large series of 100 patients with AIC (44 AIHA, 38 ITP, 7 AIN, 6 ES, and 5 AA) prospectively followed at a reference center in Milan, Italy, who underwent SARS-CoV-2 vaccination from 24 th of March until the end of June 2021. Patients (median age 62 years, range 25-89, female/male ratio 1.7) were monitored with whole blood counts and LDH testing the week before and the week after each vaccination dose. Importantly, ongoing AIC therapy (38% of cases, including steroids, cyclosporine, eltrombopag, and complement inhibitor sutimlimab) were kept stable within the 2 weeks before vaccination. Patients mainly received Pfizer-BioNtech vaccine (N=88), followed by Moderna (N=10), and Astra-Zeneca (N=2). Table 1 summarizes hematologic trends and side effects observed after each dose in patients with ITP and AIHA. Regarding the former, a delta percentage reduction of 10% or higher was observed in up to 13% of cases after the first and the second dose, requiring therapy adjustment in 2 patients. They were two elderly male subjects on low dose eltrombopag treatment and experienced a severe/moderate relapse (platelets 28 and 21x10