The Clinical phenotypes and Follow-up of 51 Chinese patients with 22q11.2 Deletion Syndrome

Abstract Objectives 22q11.2 Deletion Syndrome (22q11.2 DS) is an immunodeficiency disorder characterized by a abroad spectrum of clinical phenotypes, including facial dysmorphism, congenital heart and palate malformations, immune deficiencies, endocrine abnormalities, hypocalcemia as well as neurodevelopmental disorders. We aim to describe the clinical phenotypes and follow-up of a Chinese pediatric cohort with 22q11.2 DS. Methods A retrospective study was conducted on patients diagnosed with 22q11.2 DS from August 2008 to October 2025. The clinical, immunological, neurological and follow-up data were collected from electronic medical records. Diagnosis was confirmed using fluorescence in situ hybridization (FISH), multilink probe amplification technique (MLPA), array comparative genomic hybridization (aCGH) or whole-exome sequencing (WES). Results The general clinical manifestations of 51 patients included:(1) Facial dysmorphism (31.4%, 16/51); Palatopharyngeal malformations (21.6%, 11/51) ; Congenital heart disease (76.5%, 39/51); Endocrine abnormalities (45.1%, 23/51). (2) Immune characteristics: The incidence of recurrent infections was 31.4% (16/51); Immunomodulatory therapy (thymopentin or IVIG) was administered to 39.2% (20/51) of patients. T-cell deficiency (30/51), associated with thymic hypoplasia or aplasia (23.5%, 12/51). (3) Central nervous system characteristics: Neurological abnormalities (58.8%, 30/51), cognitive and developmental delay, epilepsy, and hypocalcemic seizures were the most common. Intelligence testing (25.5%, 13/51) revealed subnormal scores in all cases. Neuroimaging (89.7%, 35/39) commonly showed subdural hemorrhage and cerebral dysgenesis. (4) Follow-up data: As for 45 patients, T-cell immunodeficiency was in 26.7% (12/45) and ongoing immunomodulatory therapy was in 15.6% (7/45). The rate of neurodevelopmental abnormalities increased to 71.1% (32/45), learning difficulties being most common. Conclusion We found congenital heart disease combined with facial deformity should be vigilantly of 22q11.2 DS and carried out genetic testing. Systematic follow-up and monitoring of immune function and neurodevelopmental abnormalities are beneficial for improving the prognosis of the children.