Case of chromosome 22q11.2 deletion syndrome in Russian family

Abstract

Our Center for Clinical Immunology has been working in the sphere of primary immunodeficiencies (PID) for 30 years. Early diagnostics and management of PID patients is our priority.1,2 Followup of adults and children in our Center can be done as it has two main clinical bases Region Children Clinical Hospital No 1 and Region Clinical Hospital No 1 (Yekaterinburg, Ural region, Russia). Center also closely collaborates with the Institute of Immunology and Physiology of Russian Academy of Sciences and international organizations on PID jproject (collaboration with Professor L. Marodi, University of Debrecen) and Jeffrey Modell Foundation. There are 15 patients with chromosome 22q11.2 deletion (14 children and 1 adult) out of total number of 309 PID patients in our Center for Clinical Immunology. Thereby, the prospects for identifying these patients are wide. According to many reports, chromosome 22q11.2 deletion occurs 1: 3,000 6,000 live births, affecting both sexes equally.3,4 It has been reported that chromosome 22q11.2 deletion is found in 90% of the patients with disgorge phenotype, 70% of the patients with Velo-Cardio-Facial Syndrome (VCFS), and 15% of the patients with isolated conotruncal cardiac defect.5 Most of the patients were diagnosed by slightly and severely decreased immunity, facial defects, and heart anomalies and some patients had kidney abnormalities, hypoparathyroidism, hypothyroidism, and developmental retardation.6 Chromosome 22q11.2 deletion is mostly diagnosed in early childhood by pediatricians as a congenital disease so that the syndrome is difficult to diagnose in the late adulthood7‒9 In literature there are only a few works devoted to adult patients with chromosome 22q11.2 deletion syndrome.3,4,10‒12 This is due to low awareness of physicians and other specialists of chromosome 22q11.2 deletion syndrome as well as high variability of phenotypic manifestations of this syndrome and the presence of mild forms. Under our surveillance there is a family K, wherein two siblings and their mother have the chromosome 22q11.2 deletion syndrome. The purpose of this study is to analyze phenotypic manifestations in family members with chromosome 22q11.2 deletion syndrome. Methods