Prolonged viral positivity induced recurrent coronavirus disease 2019 (COVID-19) pneumonia in patients receiving anti-CD20 monoclonal antibody treatment: Case reports.

INTRODUCTION: The outbreak of novel coronavirus (severe acute respiratory syndrome coronavirus 2), which causes the coronavirus disease 2019 (COVID-19), is the most important current health problem. The number of patients is increasing worldwide. Pneumonia is the most life-threatening complication of the disease. Prolonged viral shedding in hematological patients with COVID-19 has been demonstrated; however, data on COVID-19 patients receiving anti-CD20 monoclonal antibody therapy are limited. Accordingly, focusing on humoral immunity, herein, we present 4 COVID-19 patients who were on anti-CD20 monoclonal antibody treatment and had prolonged pneumonia. PATIENT CONCERNS: Two of 4 patients were on rituximab and the other 2 were on obinutuzumab therapy. DIAGNOSIS: The polymerase chain reaction test results for severe acute respiratory syndrome coronavirus 2 were positive for all 4 patients and their COVID pneumonia lasted for >50 days. INTERVENTIONS: Although all patients were treated with an adequate amount of convalescent plasma, prolonged polymerase chain reaction positivity and prolonged pneumonia were possibly due to the lack of ability of the immune system to initiate its antibody response. OUTCOMES: Despite the administration of standard therapies, recurrent pneumonia observed in the present case series of non-neutropenic patients, in whom primary malignancies were under control. CONCLUSIONS: It is suggested that further investigations should be performed to understand the underlying pathophysiology.