A major effort to understand a not so rare immunodeficiency
Published Online: March 3, 2014
Common variable immunodeficiency (CVID) is the most frequent of the large group of primary (inborn) immunodeficiencies. As the name indicates, the disease is highly variable. While the underlying defect is a lack of antibodies in the blood, patients develop a wide range of symptoms, from respiratory infections to autoimmune disorders and neoplasms, and treating such patients poses many challenges. Notably, the replacement of antibodies (known as immunoglobulin (Ig) replacement) alone does not seem to solve all symptoms; studies in the past have tried to group patients into different phenotypes, also to help identify suitable treatment, but our understanding of the disease remains limited.
In a study recently published in The Journal of Allergy and Clinical Immunology (JACI), Gathmann and colleagues looked at 2212 patients with CVID, the largest group of such patients assembled and analyzed to date. During a period of eight years, 26 medical centers and two national registries from 16 countries contributed to the European Society for Immunodeficiencies (ESID) Registry, and using this data, focusing on the clinical presentation of patients, these researchers tried to identify correlations between symptoms that may have been overlooked. Furthermore, they investigated possible correlations between the dosing of Ig replacement and patient-reported outcomes, as well as key features affecting patient survival.
The authors found that more than a third of these patients presented their first symptoms very early (<10 years of age), which is much more frequent than has been previously noted in the literature. Males with such early-onset CVID were more prone to pneumonia and less prone to other complications, suggesting a distinct disease entity. Patients were also often diagnosed more than five years after disease onset, with the diagnostic delay particularly high in early-onset patients. This is worrying, because a higher age at diagnosis was strongly related with reduced patient survival in this study. The authors also found that patients with very low dosing of immunoglobulins showed poor clinical outcomes, whereas higher dosing levels were associated with a reduced frequency of serious bacterial infections.
The authors note that CVID patients are being managed differently throughout Europe, affecting various outcome measures. Clinically, CVID is a truly variable antibody deficiency syndrome.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.