An Interesting Case of Hypogammaglobulinemia Caused by the Combined Effect of Rituximab Infusion and Common Variable Immunodeficiency (CVID).

This case report is about a patient who presented with bilateral fungal pneumonia. He had a background of viral hepatitis-E infection five years ago, non-Hodgkin lymphoma in remission for four years, and a severe COVID-19 infection three years ago. He was found to have a common variable immune deficiency (CVID) in the background of long-standing hypoglobulinemia, which had never been evaluated. The patient had a history of rituximab infusion for the management of non-Hodgkin lymphoma, which likely worsened his hypogammaglobulinemia. This is an interesting case report that discusses hypogammaglobulinemia in the background of CVID and rituximab infusion.