Prenatal Diagnosis of Cystic Fibrosis

Abstract

The activity of γ-glutamyltranspeptidase and total alkaline phosphatase and its isoenzymes has been determined in 261 amniotic fluid samples taken from pregnant women with known normal outcome and in 30 amniotic fluid samples from pregnant women with a 1:4 risk for cystic fibrosis (CF). Preliminarily, 114 amniotic fluid samples were assayed in parallel in three different laboratories, and a good correlation was found even though different assays were used. From the results obtained in control amniotic fluids, normal range and CF-predictive cutoff values were established. No false-negative results were found in this study. Among the predicted affected pregnancies 7 were terminated, and 3 went to term: 1 resulting in a CF-affected child and the other 2 in healthy children. CF was confirmed in all the aborted fetuses. In 1 case the results were inconclusive. In this study numerical results obtained for samples with a 1:4 risk of CF analyzed in the three laboratories were always virtually identical.

Prenatal diagnosis and follow up of biliary atresia

“…If the gallbladder is undetected after two ultrasound scans, amniotic fluid sampling may exclude chromosomal abnormalities and cystic fibrosis 13 . Gastrointestinal enzyme assays are of value, as they are often diagnostic.…”

Reference values for γ‐glutamyl‐transferase in amniotic fluid in normal pregnancies

“…Between 16 and 18 weeks of gestation, the fetal gallbladder may be visualized by transvaginal ultrasound in 99.9% of cases (Blazer et al, 2002). When the fetal gallbladder is not visualized (1 : 875 cases) (Hertzberg et al, 1996;Blazer et al, 2002;Davenport and Hadzic, 2003), the differential diagnosis includes isolated atresia of the gallbladder (Ochshorn et al, 2007) (Yoon et al, 1997;Hinds et al, 2004), cystic fibrosis (Dechecchi et al, 1989;Szabo et al, 1990), left-sided galbladder (Wolman et al, 2002), and dysmorphic gallbladder. The worst prognosis is associated with EHBA, a rare (incidence 1 : 20 000) devastating disease and the main indication for liver transplantation in childhood (Davenport and Hadzic, 2003;Hinds et al, 2004;Ochshorn et al, 2007).…”