Prenatal diagnosis of echogenic lung: evolution and outcome.

OBJECTIVES: Despite the feasibility of detecting lung lesions by antenatal ultrasound, there are problems in correlating the prenatal diagnosis with the final histology and in predicting the outcome. In order to better describe these factors, we reviewed the outcome of fetuses that had been diagnosed with echogenic lung in a referral fetal medicine unit.

METHODS: We searched the database of a tertiary fetal medicine unit for all cases of fetal echogenic lung seen since 1994 and studied the maternal and neonatal records found.

RESULTS: There were 48 cases of echogenic lung diagnosed at a median gestational age of 21 (range, 19-29) weeks, including 43 (90%) cases of congenital cystic adenomatoid malformation (CCAM) and 5 (10%) of pulmonary sequestration (PS). The evolution of the fetal abnormality after diagnosis was: in 22 (45.8%) cases the lesion disappeared; in 17 (35.5%) cases the lesion remained stable and six (12.5%) cases became severe. Three (6%) women underwent termination of pregnancy. The lesions were equally distributed between the two sides of the thorax. Mediastinal shift was associated with a threefold increase in the possibility of clinical deterioration (17% vs. 5%), and the disappearance of the lesion was twice as likely to occur when the lesion was classified as microcystic as when it was macrocystic (67% vs. 36%). Features of hydrops were found in 9 (21%) fetuses and in six (13%) cases progressed and resulted in intrauterine or neonatal death. Sixty-four percent of cases with lesions that disappeared during the pregnancy had an abnormal computed tomography (CT) scan, and the prenatal diagnosis correlated with histology in 36% of these cases. Of the cases in which the lesions remained stable, 70.5% had an abnormal CT scan and the prenatal diagnosis correlated with the histology in 67% of the cases.

CONCLUSIONS: Prenatally diagnosed echogenic lung has a good prognosis in the absence of hydrops. The ability to correctly assess echogenic lung lesions and the need for surgery by prenatal ultrasound is limited.