From the Guidelines
B cell symptoms are characterized by a range of clinical manifestations, including recurrent infections, autoimmune disorders, and lymphoproliferative diseases, which can result from defects in B cell development, function, or regulation, as seen in primary immunodeficiency diseases (PIDD) such as agammaglobulinemia, hyper-IgM syndrome, and common variable immunodeficiency (CVID) 1. These symptoms can be associated with specific PIDD entities, such as:
- Agammaglobulinemia, which is characterized by a lack of B cells and recurrent infections 1
- Hyper-IgM syndrome, which is caused by abnormal B cell signaling resulting in defective class-switch recombination and somatic hypermutation 1
- CVID, which is a heterogeneous group of disorders characterized by hypogammaglobulinemia, impaired antibody responses, and increased susceptibility to infections 1 The clinical manifestations of B cell symptoms can vary widely, depending on the underlying PIDD entity, and may include:
- Recurrent infections, such as pneumonia, sinusitis, and otitis media
- Autoimmune disorders, such as autoimmune hemolytic anemia, thrombocytopenia, and rheumatoid arthritis
- Lymphoproliferative diseases, such as lymphoma and lymphoproliferative syndrome
- Gastrointestinal disorders, such as diarrhea, abdominal pain, and malabsorption The diagnosis of B cell symptoms typically involves a combination of clinical evaluation, laboratory tests, and imaging studies, including:
- Flow cytometry to evaluate B cell numbers and phenotypes
- Serum immunoglobulin quantitation to assess antibody levels
- Molecular analyses to identify genetic defects underlying the PIDD entity
- Imaging studies, such as chest X-rays and computed tomography (CT) scans, to evaluate for infections and lymphoproliferative diseases Treatment of B cell symptoms depends on the underlying PIDD entity and may include:
- Immunoglobulin replacement therapy to replace deficient antibodies
- Antibiotics to treat recurrent infections
- Immunomodulatory therapies to regulate the immune response
- Hematopoietic stem cell transplantation (HSCT) to replace the defective immune system According to a study published in the Journal of Allergy and Clinical Immunology in 2015, the diagnosis and management of primary immunodeficiency diseases, including those characterized by B cell symptoms, require a multidisciplinary approach involving immunologists, infectious disease specialists, and other healthcare professionals 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
B Cell Symptoms
B cell symptoms can be related to various autoimmune diseases, including rheumatoid arthritis (RA). The symptoms of RA include:
- Joint inflammation and pain
- Destruction of cartilage
- Formation of pannus
- Proliferation of joint synovial tissue As stated in the study 2, the global incidence of RA is about 1%, and it is more common in women.
Autoantibodies and B Cells
Autoantibodies, such as rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA), are present in RA patients and can be used as indicators of the disease 3. These autoantibodies can be produced by autoreactive B cells, which play a key role in the pathogenesis of RA. The development of autoreactive B cells in RA largely depends on the interaction with T cells, in which HLA "shared epitope" and HLA DERAA may play an important role 3.
B Cell Depletion Therapy
B cell depletion therapy has been used to treat RA, and it has been shown to be effective in reducing inflammatory indicators in RA patients 2, 4. However, this therapy can also increase the risk of infection and cancer, suggesting that it is necessary to deplete pathogenic B cells instead of all B cells 2, 4.
Primary B-Cell Immunodeficiencies
Primary B-cell immunodeficiencies refer to diseases resulting from impaired antibody production due to either molecular defects intrinsic to B-cells or a failure of interaction between B-cells and T-cells 5. Patients with primary B-cell immunodeficiencies typically have recurrent infections and can vary with presentation and complications depending upon where the defect has occurred in B-cell development or the degree of functional impairment.