Immune Features of Chromosome 22q11.2 Deletion Syndrome

Background Chromosome 22q11.2 deletion syndrome is the most common microdeletion chromosomal anomaly. Frequent infections have been described as a major feature of immunodeficiency noted in 22qDS. Immune dysregulation is also noted in 22qDS, including autoimmunity. Recurrent fevers without infections are not typically well described in 22qDS. The aim of this project was to study the noninfectious issues in 22qDS patients. Methods This was a retrospective database report from USIDNet. We collected data about patients with an International Classification of Diseases (ICD) diagnostic code for chromosome 22q11.2 deletion syndrome, velocardiofacial syndrome, and DiGeorge syndrome. We studied these patients and their encounters with recurrent fevers, cytopenias, or autoimmunity. We performed descriptive analysis. Results USIDNet cohort from 2018–2024 included 1,456 patients with ICD codes: Q93.81, D82.1, Q92.2, Q93.88, Q21.3, and O35.19X0. This cohort includes chromosome 22q11.2 deletion (n = 1,428) and chromosome 22q11.2 duplication syndrome (n = 9, encounters 26). We reviewed 20,163 encounters for these patients. Patients had a range of encounters from 0 to 299 unique encounters (0 = no encounters, diagnosis listed in problem list). Out of 1,456 patients, 134 patients had thrombocytopenia with 366 unique encounters and another 14 patients had easy bruising or bleeding accounting with 17 unique encounters, 145 patients reported recurrent fevers with 335 unique encounters, 27 patients reported arthritis or joint swelling redness with 246 unique encounters, 63 patients had neoplasms with 178 unique encounters, 77 patients had diarrhea with 142 unique encounters, and 34 patients were noted to have thyroiditis with 120 unique encounters. Conclusions Chromosome 22q11.2-related disorder deletion or duplication are associated with recurrent fevers, autoimmunity, cytopenias, and significantly contribute to the morbidity in these disorders.