OP02.30: Early ultrasonographic diagnosis of bowel obstruction, histopathological findings consistent with cystic fibrosis and negative genetic tests—a case report

Abstract

A 30-year-old patient gravida 6 para 1, was admitted at 22 weeks of gestation with recurrent vaginal bleeding. Prenatal care included a first ultrasound at 17 weeks, a triple test with an elevated AFP (2.88 MoM) and a second-trimester fetal anatomy scan at a 20th week that revealed mild hyperechogenic bowel. The examination was normal except for mild vaginal bleeding and uterine contractions which resolved after intravenous fluid administration. Blood count and coagulation factors tests were normal. Ultrasound examination showed fetal distended bowel with a lower abdominal mass appearance with hyperechogenic foci within, no ascites or calcifications, normal amniotic fluid and no other fetal anatomic abnormalities. Fetal biometry assessment showed a two week growth lag. Amniocentesis was performed, fetal karyotype was normal; TORCH and cystic fibrosis testing were negative. The couple underwent genetic counselling, mother was positive for Cystic Fibrosis (CF) mutation w1282 but the father was negative to this mutation and another 11 common mutations as well. At the 24th week, she delivered a male fetus with abdominal distention. X-ray and abdominal ultrasound showed obstruction at the level of the terminal ileum. The newborn died 18 hours after delivery. A postmortem revealed no evidence of external malformations, atresia of the terminal ileum with total obstruction of the intestinal lumen; near the atretic portion changes consistent with meconium ileus were seen. Foci of mucous deposition on the intestinal surface and calcifications were observed, all features highly suggestive of CF. The fetus was negative for the maternal CF mutation. This presentation discusses the prenatal ultrasonographic findings in non-duodenal bowel obstruction and histopathological findings in CF. This case is unique in the early detection of fetal bowel obstruction by ultrasound as well as the discrepancy between the histological and genetic results for CF.