Immune Regulation in Patients With Common Variable Immunodeficiency and Related Inborn Errors of Immunity (IEI)

This study aims to understand the causes and progression of Common Variable Immunodeficiency (CVID) and related inborn errors of immunity (IEI). These are conditions where the immune system does not function properly, leading to frequent infections and other complications such as gastrointestinal inflammation, lung and liver disease, autoimmune conditions, and an increased risk of certain cancers. By studying patients with CVI and related immune disorders, we hope to develop better ways to diagnose, treat, and prevent complications associated with these conditions. Patients diagnosed with CVID or related immune disorders must be referred by their physician and medical records reviewed by the study team to confirm eligibility to participate in this study. Once enrolled, participants will undergo various tests, including blood draws, physical exams, and imaging studies like CT scans to track changes over time. We may collect samples such as blood, urine, stool, or saliva for research purposes. If a surgical procedure or biopsy is performed because it is medically necessary, we may collect an additional sample for research testing. Family members of patients may be asked to provide blood samples for comparison. Some tests may be done remotely if participants or family members cannot travel to the study site. Who Can Participate * Patients diagnosed with CVI or related IEI, such as X-linked agammaglobulinemia, Blau Syndrome or Yao Syndrome. * Participants must be at least 2 years old. * Family members of patients may include parents, siblings, grandparents, children, aunts, uncles, and cousins. * Pregnant women already enrolled in the study will continue to participate, but new pregnant participants will not be enrolled. Potential Risks and Benefits * Risks: Blood draws may cause discomfort, bruising, or infection. Apheresis may cause dizziness, nausea, or muscle cramps; this procedure is to collect specific cells in the blood and is infrequently done on this protocol. Extra biopsies during clinically indicated procedures may increase the risk of complications; they will only be collected after the medically necessary biopsies are taken and if it is safe to collect any extra biopsies. * Benefits: Participants may not receive direct medical benefits, but the study will contribute to a better understanding of CVID and related conditions, potentially leading to improved treatments.