P52 DIGEORGE SYNDROME: HYPOCALCEMIC PARALYSIS AND INTERVENTRICULAR DEFECT

Abstract

Abstract Introduction DiGeorge syndrome (DGS), known as "22q11.2 deletion syndrome" (22q11DS) (MIM#192430#188400), is caused by microdeletion of the long arm of chromosome 22 resulting in impaired development of the pharyngeal pouch. It is the most frequent chromosomal microdeletion syndrome with an estimated prevalence of 1 in 3 in 6,000 live births and approximately 1 in 1,000 fetuses. 22q11DS is the second leading chromosomal cause of congenital heart malformations, after trisomy 21. Patients with DGS may have developmental abnormalities of the craniofacial structures, parathyroid glands, thymus, and cardiac outflow tract. Doctors have been screening infants with conotruncal heart abnormalities for DGS since the late 1990s, before which the diagnosis was only clinical. Clinical case A 48–year–old woman came to our attention for recurrent episodes of tetanus paresis, the worst in her youth, associated with a systolic murmur. Her face was characterized by hypertelorism, thin lips, micrognathia, and low–set ears associated with short stature. Blood chemistry tests showed hypocalcemia during the tetanic crisis, exacerbated also during blood pressure measurement (Trosseau‘s sign with obstetrician‘s hand). The electrocardiogram showed sinus rhythm, high QRS voltages and the presence of U wave in some precordial leads (Fig. 1). The echocardiographic examination showed a globular left ventricle with evidence of a subaortic interventricular defect (Fig.2). The patient was sent for genetic evaluation with subsequent evidence of 22q11.2 microdeletion (Di George syndrome) and placed on oral calcium treatment and cardiac surgery evaluation for possible correction of the congenital defect. At the same time, psychological support was guaranteed for adequate coping with the diagnosed disease. Conclusions The presence of multiple stigmata in the same patient, such as typical facies, congenital heart defects and hypocalcemia, must raise the suspicion of syndromic involvement of the patient and consequent genetic evaluation oriented towards diagnosis and adequate counseling.