Relationship of non-visualization of the fetal gallbladder and amniotic fluid digestive enzymes analysis to outcome

The aims of this study were evaluate the significance of non-visualization of fetal gallbladder at routine ultrasound scan in a series of 102 cases and to determine the contribution of amniotic fluid digestive enzyme (AF-DE) analysis towards the outcome.

This is a multicenter retrospective study. Outcome of pregnancies, karyotype, and result of screening for CFTR gene mutations were known in all cases. Amniotic fluid gamma-glutamyl-transpeptidase and intestinal alkaline phosphatase isoenzyme were assayed.

Non-visualization of the fetal gallbladder was associated with a severe disease in 25 cases (cystic fibrosis in ten, biliary duct atresia in eight, digestive tract anomalies in six, and chromosomal anomaly in one). In the remaining 77 cases, gallbladder agenesis was diagnosed in 22, and in 55, the gallbladder was subsequently demonstrated. Before 22 weeks of gestation (n=30), an abnormal AF-DE pattern had a 90% sensitivity and 80% specificity in detecting cystic fibrosis or biliary duct atresia. After 22 weeks, sensitivity fell to 53%. The AF-DE pattern was normal in 82% of gallbladder agenesis cases (benign) and in 91% of the cases where the gallbladder was subsequently detected.

Non-visualization of the fetal gallbladder was associated with severe anomalies in 24% of cases. Prior to 22 weeks, determination of AF-DE contributes to the prediction of biliary atresia or the presence of cystic fibrosis.