Laboratoire de Génétique Moléculaire, CHU de Montpellier, Montpellier, France,
Laboratoire de Génétique de Maladies Rares EA7402, Université de Montpellier, Montpellier, France,
Fetal Diagn Ther. 2019;45(5):312-316. doi: 10.1159/000489120. Epub 2018 Jun 19.
Cystic fibrosis (CF) can be revealed during fetal life by diverse ultrasound digestive abnormalities (USDA) such as fetal echogenic bowel or fetal intestinal loop dilatation, nonvisualization of the fetal gallbladder (NVFGB) being rarely observed in isolation. Only 6 cases of CF revealed by isolated NVFGB have been reported so far in the literature. Furthermore, recent studies suggested that this sign is of poor predictive value for CF.
We report on the results of a 6-year French tricenter study on 1,124 cases of fetal USDA for whom a comprehensive molecular study was performed for CF.
Among the 37 CF fetuses, 5 (13.5%) presented with isolated NVFGB at ultrasound (US) examination at 24-31 weeks of gestation. This sign was more frequently observed in CF fetuses than in non-CF fetuses, with a likelihood ratio of 2.7. The genotypes included three c.1521_1523del (F508del) homozygous cases and two compound heterozygous cases for a frequent and a rare CF-causing variant.
These observations highlight the importance to report on the presence and aspect of the fetal gallbladder at the second trimester US scan and to consider prenatal CFTR molecular analysis in cases of isolated NVFGB.
囊性纤维化 (CF) 可在胎儿期通过多种超声消化系统异常 (USDA) 显现，例如胎儿回声肠或胎儿肠袢扩张，而胎儿胆囊未显影 (NVFGB) 则很少单独出现。迄今为止，文献中仅报道了 6 例由孤立性 NVFGB 揭示的 CF 病例。此外，最近的研究表明，该征象对 CF 的预测价值较差。
我们报告了一项为期 6 年的法国 3 中心研究结果，该研究对 1124 例胎儿 USDA 进行了综合分子 CF 研究。
在 37 例 CF 胎儿中，有 5 例（13.5%）在妊娠 24-31 周的超声检查中出现孤立性 NVFGB。该征象在 CF 胎儿中比非 CF 胎儿更为常见，其似然比为 2.7。基因型包括三个 c.1521_1523del（F508del）纯合子病例和两个常见和罕见 CF 致病变异的复合杂合子病例。
这些观察结果强调了在第二次孕期超声扫描时报告胎儿胆囊的存在和形态的重要性，并在出现孤立性 NVFGB 时考虑进行产前 CFTR 分子分析。
