Prenatal karyotyping of choroid plexus cysts

Clinical characteristics and survival of trisomy 13 in a medical center in Taiwan, 1985-2004

BACKGROUND

This study investigated the survival and natural history of trisomy 13 in a series of patients, comparing the management and outcome before and after the implementation of Taiwan's National Health Insurance program (NHI).

METHODS

A total of 28 cases of trisomy 13 seen at Mackay Memorial Hospital, Taipei, Taiwan, from 1985 to 2004 were retrospectively reviewed. Survival and management before (12 cases) and after (16 cases) the implementation of National Health Insurance were compared, and structural defects, imaging findings, and cytogenetic results were analyzed. The cases that were diagnosed prenatally, and finally terminated, were excluded from this study. The diagnosis of trisomy 13 was based on the postnatal chromosome analysis.

RESULTS

All patients except one with trisomy 13 translocation died in their first year because of severe malformations of the cardiovascular or central nervous system. The median survival was 9 days. After implementation of National Health Insurance, survival with trisomy 13 was significantly longer than before (P < 0.05). The three most common structural defects were abnormal auricular helices or low-set ears (89%), cryptorchidism and abnormal scrotum of male (73%) and cleft lip and/or palate (71%). Using echocardiography, the most commonly detected heart defects were patent ductus arteriosus (68%), ventricular septal defect (50%) and atrial septal defect (50%), and eight cases (36%) had complex congenital heart defects. The most common brain lesion was lenticulostriate vasculopathy (22%), followed by holoprosencephaly (17%), brain edema (13%) and subependymal cyst (13%).

CONCLUSIONS

Early diagnosis and the survival patterns from the data collected should be used to inform parents and health-care professionals to assist in decision making. Although most patients with trisomy 13 die within the first weeks after birth, it is important to recognize that a few may survive the first year. When counseling families, the long-term survival prospects of trisomy 13 patients should be included.

Karyotyping of fetuses with isolated choroid plexus cysts is not justified in an unselected population

OBJECTIVE

The main objective of this study was to determine whether isolated choroid plexus cysts are a risk factor for trisomy 18.

METHODS

A total of 12,672 unselected patients were examined, and the outcome of fetuses with choroid plexus cysts was assessed. The cases with choroid plexus cysts were selected from the 12,672 patients and further divided into cases with minor markers of aneuploidy and cases with associated structural anomalies. Previous similar work was reviewed, analyzed, and, where possible, compared with the results of this study.

RESULTS

The findings revealed 366 fetuses with choroid plexus cysts (2.9%). Thirty-three percent of fetuses with trisomy 18 had choroid plexus cysts, and, in every case, structural anomalies were also present. From the 12 cases with choroid plexus cysts in addition to major associated anomalies, amniocentesis revealed 2 cases of trisomy 18. Forty-three patients who had choroid plexus cysts and minor anomalies within our population had normal outcomes.

CONCLUSIONS

These results indicate that the risk of amniocentesis is not acceptable if isolated choroid plexus cysts are isolated findings. More data are needed to establish whether choroid plexus cysts and other soft signs independently increase the risk of aneuploidy.

Choroid plexus cysts in the mid-trimester fetus--practical application suggests superiority of an individualized risk method of counseling for trisomy 18

OBJECTIVES

Analysis of a referral population of patients with choroid plexus cysts (CPCs) was performed to compare an average risk method of counseling to an individualized risk method.

METHODS

A total of 395 patients referred to a Prenatal Diagnosis Center were included, of whom 341 had isolated CPCs and 54 had associated ultrasound abnormalities. For isolated CPCs, an average risk of 1/150 for aneuploidy was compared to an individualized risk assessment [prior risk as determined by maternal age or serum screening multiplied by the likelihood ratio established by Gupta et al. (1997)]. Accuracy, cost, and procedure-related losses were assessed.

RESULTS

Both methods resulted in 100% sensitivity. The individualized method resulted in greater specificity, decreased costs, and (theoretically) fewer procedure-related pregnancy losses.

CONCLUSIONS

An individualized risk method of counseling utilizing the likelihood ratios established by Gupta et al. (1997) was superior to an average risk method for assessing trisomy 18 risk in the setting of CPC detected in mid-trimester.