COVID-19-Induced Hyperleucocytosis in Chronic Lymphocytic Leukaemia.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus responsible for the current global pandemic, coronavirus disease 2019 (COVID-19). COVID-19 usually presents with respiratory symptoms but can affect multiple organ systems. A wide spectrum of complications can occur depending upon the comorbidities of patients. There is limited literature available regarding the presentation and outcome of COVID-19 in chronic lymphocytic leukaemia (CLL) patients. We report 2 cases of COVID-19-induced hyperleucocytosis (WBC count >100,000/μl) in CLL patients. LEARNING POINTS: Lymphopenia has been associated with severe disease and is a poor prognostic factor in COVID-19 infected patients; however, our cases show COVID-19-induced hyperleucocytosis (WBC count >100,000/μl)/lymphocytosis in CLL patients.Prior reports suggest that ibrutinib may have a protective effect against COVID-19 by decreasing inflammation and preventing progression to ARDS. © EFIM 2021.