Diagnosis and outcome in nonhydropic fetal pleural effusions

To determine the outcome of all pregnancies with nonhydropic fetal pleural effusions in the Wessex region.

Data were extracted from the Wessex congenital anomaly database for the years 1994-2015 inclusive.

Sixty-two fetuses and babies were identified giving a total prevalence of 1:9500. Eight fetuses had bilateral effusions with additional, nonhydrops anomalies, and 54 had isolated effusions. Of the isolated cases, 36 presented before 24-week gestation: 12 were unilateral and 24 bilateral. All of the unilateral effusions resolved before or soon after birth with no other diagnosis but of the bilateral cases, four (17%) had a trisomy and three (13%) a genetic or syndrome diagnosis. Eighteen isolated cases presented after 24-week gestation, six were unilateral of which one had trisomy 21 (17%), and three (50%) Noonan's or another lymphoedema syndrome. Twelve were bilateral: One had trisomy 21, one an unbalanced translocation (17%), three had Noonan's or another lymphoedema syndrome, and two an unspecified syndrome (42%) at birth.

These data suggest that a chromosomal microarray should be offered to all fetuses presenting with a pleural effusion in the absence of hydrops, and Noonan's syndrome testing should be considered for those that develop after 24 weeks.

To determine the outcome of all pregnancies with nonhydropic fetal pleural effusions in the Wessex region from 1994-2015.