Incidence of Chromosomal Abnormalities in the Presence of Fetal Subcutaneous Oedema, Such as Nuchal Oedema, Cystic Hygroma and Non-Immune Hydrops

Abstract

Introduction: The authors investigated the incidence of chromosomal abnormalities in subcutaneous oedema detected in the fetus by intrauterine ultrasonography. Material and Method: In the 10-year period, intrauterine karyotyping was performed in pregnancies with positive ultrasound findings for subcutaneous oedema, such as nuchal oedema, cystic hygroma and non-immune hydrops. Results: Intrauterine karyotyping in fetal subcutaneous oedema was carried out in 434 cases. The chromosomal investigation was made in nuchal oedema in 374 cases, in 120 patients the chromosomal examination was made in the first trimester because of nuchal translucency, and in 254 cases in the second trimester because of nuchal thickening. Cystic hygroma cases (27 patients), non-immune hydrops cases (20 patients), and combined cases of non-immune hydrops and cystic hygroma (13 patients) were investigated separately. In nuchal oedema, pathological karyotypes were detected in 8.33% in the first trimester and in 5.51% in the second trimester. Chromosomal abnormality was found in 48.15, 20, and 53.8% in cystic hygroma, non-immune hydrops, and combined occurrence of non-immune hydrops and cystic hygroma, respectively. Considering all of the changes accompanied by subcutaneous oedema, 50, 25 and 18.75% of the pathological karyotypes was X-monosomy, trisomy 18 and trisomy 21, respectively. Discussion: It was important to distinguish nuchal oedema and cystic hygroma, and in the case of non-immune hydrops, it was also important to discuss cases with or without cystic hygroma separately. During the investigations, cases of non-immune hydrops with or without cystic hygroma were evaluated as separate categories. Conclusions: The authors emphasize the differentiation of the various types of subcutaneous oedema and the importance of precise information about the risks, provided during genetic counselling.