fa پژوهشي اصیل Original Research Digeorge syndrome is caused by microdeletion of a large region of chromosome 22q11.2 lead to the abnormal&nbsp;development of the third and fourth pharyngeal pouches. This syndrome is characterized by hypoparathyroidism,&nbsp;cellular immune deficiency secondary to thymic hypoplasia, congenital heart disease and dysmorphic&nbsp;facial features. In this case report, we describe a 4month old boy who presented with respiratory distress due to<br> cardiac anomaly (Large PDA) that was hypocalcemic, thrombocytopenic, lymphopenic and had hepatomegaly<br> and history of seizure in neonatal period.<br> Because of recurrent opportunistic infection, this infant was suspected of immune deficiency. He died after&nbsp;about 4 month hospitalization due to severe sepsis and multi organ failure feature. Genetic study confirmed&nbsp;chromosomal 22q11.2 deletion and Digeorge syndrome after his death. 13 15 http://ijca.iums.ac.ir/browse.php?a_code=A-10-1-59&slc_lang=fa&sid=1 Ahmad Bahrami 1003194753284600498 1003194753284600498 No Iran University of Medical sciences, Tehran, Iran. Behzad Haghighi Aski 1003194753284600499 1003194753284600499 No Pediatrics Intensivist, Division of Intensive Care Unit, Ali Asghar Hospital Ali Manafi Anari 1003194753284600500 1003194753284600500 No Iran University of Medical sciences, Tehran, Iran. Ramin Zare Mahmood Abadi 1003194753284600501 1003194753284600501 No Iran University of Medical sciences, Tehran, Iran. Saeid Talebi 1003194753284600502 1003194753284600502 No Iran University of Medical sciences, Tehran, Iran. Sara Kalantar 1003194753284600503 1003194753284600503 Yes Pediatrics Resident, Ali Asghar Hospital