Zespół mikrodelecji 22q11.2 (zespół DiGeorge’a) bez współistniejącej wady serca – analiza fenotypu pacjentów i problemy diagnostyczne

Abstract

IntroductionDeletion of chromosome 22q11.2, which causes DiGeorge syndrome, is one of the most frequently diagnosed microdeletion syndromes in the human. It is characterised by a wide variety of symptoms. The main symptoms consist of congenital heart diseases, particularly conotruncal malformations, characteristic facial dysmorphism, palatal abnormalities, an immune deficiency and hypocalcemia.We present phenotypical analysis of 15 patients with DiGeorge syndrome without structural heart disease. A diagnosis of DiGeorge syndrome was confirmed by Multiplex Ligation-dependent Probe Amplification (MLPA) and Fluorescent in situ Hybridization (FISH) with a specific probe. ResultsFISH method was used in 10 patients in genetic diagnosis of microdeletion 22q11.2 syndrome, and MLPA method confirmed that FISH analysis was used in 5 patients. None of the patient exhibited heart disease in an ultrasound examination. Developmental delay (13/15), delay in emergence of language (8/15), palatal abnormalities (10/15) and frequent infections (11/15) were observed. All the patients presented characteristic facial features. ConclusionsIt is difficult to diagnose DiGeorge syndrome in patients who do not present heart disease. In such cases careful phenotypical analysis and microdeletions screening with MLPA method may be helpful to make a diagnosis.To establish appropriate therapy and further clinical evaluation exact and early diagnosis is crucial. There lacks diagnostic guidelines for patients with unexplained developmental delay and/or developmental malformations.