[TREATMENT WITH CONVALESCENT PLASMA IN PATIENTS WITH HUMORAL IMMUNE SYSTEM IMPAIRMENT AND PERSISTENT PULMONARY COVID-19 - CASE SERIES].

Introduction: Patients with immunosuppression due to severe B cell depletion, such as those with hypogammaglobulinemia or those treated with B-cell suppressive medications, may experience prolonged replication and shedding of SARS-CoV-2. Their inability to mount a sufficient antibody response to clear the virus places them at risk for developing persistent pulmonary COVID-19 (PPC). PPC has mainly been described in case reports and case series. An awareness gap exists among physicians as to the risk factors, clinical manifestations and means of diagnosis and treatment of the disease. This article presents five cases of immunocompromised patients who received at least two doses of COVID-19 vaccination and developed PPC, which is defined by the presence of respiratory and systemic symptoms for ≥14 days, typical imaging findings, and a positive COVID-19 PCR test from a nasal swab or bronchoalveolar lavage (BAL). The patients received convalescent plasma during hospitalization, and no adverse effects related to the plasma were documented. Three out of five patients experienced clinical improvement within a few days post-infusion, one showed gradual improvement, and the last patient required multiple doses of plasma in order to achieve a cure. In all cases, there was resolution of pulmonary opacities on imaging, along with a decrease in inflammatory markers. This case series strengthens the importance of awareness and knowledge of the syndrome, and further establishes the efficacy of treatment with convalescent plasma. Additionally, the article discusses indications for convalescent plasma in the treatment of persistent COVID-19 infection in immunosuppressed patients.