Prenatal evaluation of a fetus with trisomy 18 and additional balanced de novo Rob(13;14).

The main aim of this work is to present unusual case with full trisomy 18 and additional robertsonian translocation- Rob (13;14) detected through abnormalities found in prenatal ultrasound examination. A 26 years-old pregnant women with no family history of any reproductive failure underwent level II ultrasound screening in 19 weeks of gestation. Polyhydramnios, intrauterine growth retardation, hydrocephalus, enlarged lateral ventricles, club foot and cardiac defect were found. Amniocentesis was indicated considering the high likelihood of a chromosomal aberration. Abnormal karyotype was detected 46, XY, der(13;14)(q10;q10), +18. Karyotypes of parents were normal, what confirmed de novo origin of this aberration. Pregnancy was terminated. In postnatal examination fetus demonstrated intrauterine groth retardation and a lot of dysmorphic features characteristic for trisomy 18: microcephaly, prominent occiput, very low set and posteriorly rotated ears, hypertelorism, small mouth, small recessed mandible, a high narrow palate, broad nasal bridge, low-set ears, preauricilar skin appendage, clenched fingers clinodactyly of Vth fingers and club foot. In conclusion it is worth to say that our described fetus demonstrated rather typical for trisomy 18 ultrasonographic features. Balanced Rob (13;14) gives no phenotypic expression. Possible interchromosomal effect in complex chromosomal aberration formation such as Rob (13;14) with trisomy 18 was discussed.