LATE THIRD TRIMESTER ULTRASOUND DIAGNOSIS OF DUODENAL ATRESIA- THE IMPORTANCE OF DETAILED PRENATAL ULTRASOUND SCREENING


J.A. Akinmoladun1, T.A. Lawal2, and A. Hafiz1

  1. Department of Radiology, University College Hospital, Ibadan. Oyo State, Nigeria
  2. Department of Peadiatric surgery, University College Hospital, Ibadan. Oyo State, Nigeria.

Abstract

Duodenal atresia (DA) is the commonest type of congenital small bowel obstruction usually presenting in the neonatal period. About half of fetuses with duodenal atresia have other associated anomalies, and these associations often contribute to morbidity and mortality. DA can be fatal unless promptly diagnosed and treated surgically. In experienced hands and in countries where prenatal ultrasound screening for anomalies is routine, DA can be confidently diagnosed prenatally, which can help in reducing the perinatal morbidity and mortality associated with diagnosis after delivery. We report a case of DA diagnosed by ultrasonography at 36 weeks gestation in a 34 year old multiparous woman in a hospital where targeted prenatal ultrasound screening for fetal anomalies was recently introduced, and reviewed relevant literature

Keywords: Prenatal Ultrasound screening, Duodenal Atresia.

Correspondence:

Dr. J.A. Akinmoladun
Department of Radiology,
Faculty of Clinical Sciences,
University of Ibadan, Ibadan,
Oyo State, Nigeria
Email: jaakinmoladun@yahoo.com

Introduction

Duodenal atresia (DA) is a congenital anomaly usually presenting in the neonatal period with upper gastrointestinal obstruction1. Although detailed statistics are not available in much of Africa, the incidence of duodenal obstruction is reported to be 1 in 5,000 – 10,000 births2.Duodenal atresia is the commonest cause of congenital small intestinal obstruction1,2.

DA is associated with polyhydramnios in 45% of cases and with symmetric growth retardation in 50% of cases. Importantly, nearly 50% of patients with DA have associated congenital malformations,2 of these, 30% have Trisomy 21, 22% have malrotation of the gut while 20-30% have congenital heart disease 3, 4. The presence of associated anomalies and delay in diagnosis contribute to morbidity and mortality in children with neonatal intestinal obstruction. This is more obvious in developing countries, especially in those lacking formal birth defect screening programs.

The prenatal diagnosis of duodenal atresia can be made sonographically by the demonstration of the fluid filled dilated stomach and duodenum, which gives the typical “double bubble” sign on ultrasound3. Postnatally, the imaging diagnosis of duodenal atresia is usually first made on neonatal radiograph by demonstrating the same “double bubble” sign, which is due to a gas filled distended stomach and duodenal bulb5. Prenatal detection of DA helps in reducing the morbidity and mortality associated with late presentation5, 6.

We report a case of DA diagnosed prenatally by ultrasonography at 36 weeks of gestation in a 34year old multiparous woman who had corrective surgery within 48 hours of life.