Non-Hodgkin lymphomas (NHL) are frequently associated with immunodeficiencies, both primary, which contribute to lymphomagenesis through chronic immune activation, genomic instability, and impaired immune surveillance, and secondary (acquired), caused by the disease itself and its treatment, leading to an increased risk of infections and complicating therapy. Primary immunodeficiencies, such as common variable immunodeficiency and Wiskott-Aldrich syndrome, promote lymphomagenesis through genetic defects (e.g., TNFRSF13B, WAS) and persistence of oncogenic viruses. In patients with NHL, immune function is impaired due to the replacement of normal lymphocytes with malignant cells or as a result of reduced B-cell counts and decreased immunoglobulin production. Hypogammaglobulinemia, characteristic of B-cell NHL, and T-cell dysfunction increase the risk of bacterial, viral, and fungal infections. A significant proportion of modern therapeutic approaches for NHL exacerbate immunodeficiency. Specifically, anti-CD20 monoclonal antibodies (e.g., rituximab) induce profound and prolonged B-cell depletion, resulting in persistent hypogammaglobulinemia and an elevated risk of infections. Other components of the R-CHOP regimen further enhance immunosuppression: cyclophosphamide and doxorubicin cause neutropenia, while prednisolone suppresses T-cell functional activity, with immunodeficiency persisting for over two years.

Immunodeficiency in NHL significantly increases patients’ susceptibility to infections, which are a major cause of morbidity and mortality. Clinical consequences include bacterial, viral, and fungal infections, which may become recurrent, as well as opportunistic infections (e.g., Pneumocystis jirovecii), sepsis, reactivation of hepatitis B virus, and reduced overall survival. Recommendations for managing these patients include screening for immunoglobulin and lymphocyte levels, antibacterial, antiviral, and antifungal prophylaxis, and intravenous immunoglobulin replacement therapy for IgG levels <4 g/L, along with monitoring immunological parameters for two years to improve prognosis and overall survival.

Keywords: review, non-Hodgkin lymphomas, immunodeficiency, hypogammaglobulinemia, rituximab, infectious complications.