SARS-COV2 Infection in Vaccinated Patients: Look for Clinical History and Test Humoral Immunity

Abstract

On August 1st, a 72 year-old man was diagnosed with SARS-CoV2-positive bilateral broncopneumonia despite full dose of mRNA anti-SARS-CoV2 vaccine was inoculated two months before (Fig. 1). Hypogammaglobulinemia (0,40 g/dl; IgG 449 mg/dl; IgM 18 mg/dl), lymphopenia (270/mmc) with total B-cells absence (Fig. 2) were also found. Clinical history revealed chronic obstructive respiratory disease and low grade non-Hodgkin lymphoma treated elsewhere 14 years before for massive bone marrow involvement and splenomegaly with montly cyclophosphamide, adryamicin, oncovin and anti-CD20 monoclonal antibody Rituximab for 6 cycles. One year later, he was treated with fludarabine and rituximab because of disease refractoriness (3 cycles) with the achievement of complete remission. Since then, the patient was followed in continue complete remission. The underlying disease affecting immune system (lymphoma), the treatment given (including targeting B-cells monoclonal antibody and fludarabine), and the severe humoral immunity impairment (lymphopenia, no detectable CD20 ? B-cells, hypogammaglobulinemia) could explain the severe immunodeficient status preventing an appropriate response to vaccination. As a matter of the fact circulating anti-S antibodies were detected at very low levels (16.7 UI/ml). This case shows that accurate clinical history and lab tests addressing humoral immunity are mandatory in patients who received anti-SARS-CoV2 vaccine and were however infected [1, 2].