Evaluation of the immunological findings of the patients who were followed up by Hacettepe University Ihsan Doğramaci Children's Hospital with the diagnosis of digeorge syndrome

DiGeorge Syndrome (DGS) is one of the most common genetic diseases that is developmental anomaly of the third and fourth pharyngeal arch. Phenotypic findings and immune system involvement show a wide spectrum in DGS whose classical triad is thymus hypoplasia, conotruncal cardiac defect and hypocalcemia. The aim of our study is to evaluate the clinical and immunological characteristics of patients with DGS. Seventy-two patients who were followed up with the diagnosis of DiGeorge Syndrome in the Immunology and/or Genetics Department of Hacettepe University İhsan Doğramacı Children's Hospital between January 2000 and March 2019 were included in the study. The mean age at diagnosis was 3.6 ± 4.8 years, and the mean follow-up period was 100 ± 121.9 months. 43.1% (n: 31) of them were women, 56.9% (n: 41) were men, two (2.8%) patient's parents had a diagnosis of DGS. The most common presentations were cardiac findings (30.6%), neurological findings (15.3%), growth retardation (15.3%), infections (12.5%) and cleft palate (12.5%). Serum IgM, IgA and IgG levels were low according to the age-appropriate reference range in 36.2%, 14.5%, and 5.8% of the patients respectively. The IgE value was below 5 IU/ml in 27.8% of the patients. The CD4+, CD3+, CD19+ and CD8+ lymphocyte counts were low according to the age-appropriate reference range in 48.5%, 38.8%, 22.4% and 19.5% of the patients respectively. CD4+ TEMRA cell percentage was low in approximately half of the patients, while none of the patients had low CD8+ TEMRA. Effector memory CD4+ cells were low in 11.5% of patients, and effetor memory CD8+ cells were low in one third of the patients. Transitional B cells were low in 66,7% of the patients. More than half of the patients had normal percentages of other T and B cell subgroups according to the age-appropriate reference range. Lymphocyte activation was normal in most of the patients. The most of the patients with decreased lymphocyte activation had low IgA levels. The most common clinical findings in our patients were dysmorphism (97%), congenital cardiac defects (78.5%), growth retardation (75.7%), seizure (39.4%), hypocalcemia (30.4%), malnutrition (29.9%) and cleft palate (23.9%). Six (8.3%) out of 72 patients died during the follow-up period. The cause of death was congenital heart disease in four patients, sepsis in one and disseminated intravascular coagulation in one patient.