Risk of chromosome abnormalities in the presence of bilateral or unilateral choroid plexus cysts.

OBJECTIVES

To evaluate the rate of chromosome abnormalities in cases of uni- and bilateral choroid plexus cysts (CPCs).

METHODS

A total of 10,875 ultrasound (US) examinations were performed in the second trimester, and 435 cases with CPC (4%) were found. After genetic counseling, 45 patients decided not to undergo karyotyping. The authors performed a chromosome analysis in 390 cases of CPCs.

RESULTS

The total risk of chromosome abnormalities was 3.59% (n = 14) and risk of trisomies was 2.05% (n = 8). Trisomy 18 was found in 6 cases (1.54%), trisomy 21 in 1 case (0.26%), and trisomy 9 in 1 case (0.26%). The risk of 45,X karyotype was 0.77% (n = 3). One case of 47,XXY karyotype and 2 cases with other chromosome abnormalities were found. In 212 unilateral cases there were 7 with chromosome abnormalities (3.3%). In 178 bilateral cases there were 7 with abnormal karyotypes (3.93%). The CPC was associated with additional fetal US anomalies (with or without polyhydramnios/oligohydramnios) in 112 cases; chromosome abnormalities were detected in 4 cases (3.57%). 66 cases were associated with polyhydramnios/oligohydramnios but not with other fetal US anomalies; 3 cases of abnormal karyotypes were found (4.55%). The CPC was isolated in 212 cases and 7 cases were associated with chromosome disorders (3.3%).

CONCLUSIONS

US plays an important role in prenatal diagnostics. Further genetic counseling is recommended in cases with CPCs.