Two Sides of the Same Coin: Pediatric-Onset and Adult-Onset Common Variable Immune Deficiency

Common variable immunodeficiency (CVID) is a complex, heterogeneous immunodeficiency characterized by hypogammaglobulinemia, recurrent infections, and poor antibody response to vaccination. While antibiotics and immunoglobulin prophylaxis have significantly reduced infectious complications, non-infectious complications of autoimmunity, inflammatory lung disease, enteropathy, and malignancy remain of great concern. Previous studies have suggested that CVID patients diagnosed in childhood are more severely affected by these complications than adults diagnosed later in life. We sought to discern whether the rates of various infectious and non-infectious conditions differed between pediatric-diagnosed (ages 17 or younger) versus adult-diagnosed CVID (ages 18 or older). Using the United States Immunodeficiency Network (USIDNET) database, we performed a retrospective analysis of 457 children and adults with CVID, stratified by age at diagnosis. Chi-squared testing was used to compare pediatric versus adult groups. After correcting for multiple comparisons, we identified few statistically significant differences (p <= 0.0004) between pediatric and adult groups. Pediatric-onset CVID patients had more frequent diagnoses of otitis media, developmental delay, and failure to thrive compared with adult-onset CVID patients. Adult CVID patients were more frequently diagnosed with bronchitis, arthritis, depression, and fatigue. Diagnoses of autoimmunity, lymphoma, and other malignancies were higher in adults but not to a significant degree. Serum immunoglobulins (IgG, IgA, and IgM) and lymphocyte subsets did not differ significantly between the two groups. When complications of infections and co-morbid conditions were viewed categorically, there were few differences between pediatric-onset and adult-onset CVID patients. These results suggest that pediatric CVID is not a distinct phenotype. Major features were comparable across the groups. This study underscores the need for continued longitudinal study of pediatric and early-onset CVID patients to further characterize accrual of features over time.