UMBILICAL CORD PSEUDOCYST IN A FETUS WITH TRISOMY 21

Purpose: Umbilical cord cysts are often categorized as true cysts or pseudocysts. Pseudocysts tend to be located close to the fetal insertion of the cord. These cysts can be found in the first trimester, if they insist on occurring in the second trimester, they are strongly associated with chromosomal disorders and structural defects, especially with Trisomy 18 in which other abnormalities are often detected in the ultrasonography. However, these cystic masses have attracted little attention in trisomy 21, especially when they are isolated. We aim to present the isolated umbilical pseudocyst in trisomy 21.

Methods and Materials: A cystic mass in the umbilical cord was found by sonography in a 19-year-old patient in 28th week of her first pregnancy.

Results: In the gray scale images, it was located near the fetal insertion of the cord and lying through abdominal wall. Color Doppler imaging revealed that there was no blood stream in the cyst which encircled the three umbilical vessels. Although we could not find any additional findings of chromosomal abnormalities except for pseudocyst in the detailed fetal ultrasonographic examination, we decided to do amniocentesis. Karyotyping confirmed the diagnosis of trisomy 21.

Conclusions: In our case, isolated umbilical pseudocyst led us to the karyotype analysis.

If the umbilical cord cysts are detected in the second trimester of pregnancy, we recommend detailed sonographic examination and amniocentesis.