INCREASED NUCHAL TRANSLUCENCY IN A FETUS WITH A NORMAL KARYOTYPE: CASE REPORT
Nuchal translucency (NT) is the normal fluid filled subcutaneous space measured at the back of the fetal neck measured in the late first trimester and early second trimester. Nuchal translucency screening can detect approximately 80% of fetuses with Down syndrome and other major aneuploidies with a rate of 5% of false positive results, but the merger of the NT screening with β-hCG and PAPP-A testing increases the detection rate to 90%. We present the case of a fetus with a NT of 49 mm detected at the first trimester ultrasound morphologic exam. The Kryptor test revealed a 1:35 risk for Trisomy 13 and 1:721 for Trisomy 18. We report the case of an investigated pregnancy with a NT of 49 mm detected at the first trimester ultrasound exam, with a risk of 1:35 for Trisomy 13 and 1:721 for Trisomy 18 calculated at the Kryptor test. A chorionic villus sampling was recommended and performed with a result of 46XY normal karyotype. The particularity of this case is represented by the increased nuchal translucency as well as an increased risk for trisomy 13 and 18 in a normal karyotype fetus that had a normal development in the second and third trimester with no pregnancy complications arising.
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