Difficulties in prenatal diagnostics trisomy 20 and its mosaic

Authors: A. Staníková 1;  I. Grochová 2;  I. Borek 1
Authors‘ workplace: Neonatologické oddělení FN Brno primář MUDr. I. Borek 1;  Centrum prenatální diagnostiky, Cytogenetická laboratoř, Brno vedoucí MUDr. P. Vlašín 2
Published in: Čes-slov Pediat 2012; 67 (6): 390-392.
Category: Case Report


Trisomy of chromosome 20 is probably not compatible with life, whereas the mosaic of trisomy 20 belongs to most frequent chromosomal aberrations in general, mostly with a favorable phenotype. Our case report deals with a newborn of prenatally diagnosed complete trisomy 20 in amniocytes. It was not confirmed in peripheral blood after birth. However, subsequent examination of caryotype from buccal mucosa cells as well as the urinary sediment revealed mosaic of trisomy 20. The patient suffers from inborn developmental defect of uropoietic and cardiovascular system.

The aim of the case report is to draw attention to difficulties in the diagnostics of chromosomal aberrations. The prognosis of a specific newborn cannot be precisely defined without a detailed prenatal and, especially, postnatal examination.

Key words:
trisomy 20, mosaicism, chromosomal aberrations, prenatal diagnostics


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Neonatology Paediatrics General practitioner for children and adolescents
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