PRENATAL SONOGRAPHIC "DOUBLE-BUBBLE" APPEARANCE OF DUODENAL ATRESIA AND ITS ASSOCIATION WITH DOWN SYNDROME

Objective: - To describe the prenatal sonographic “double-bubble” appearance of duodenal atresia and further comment on its association with Down syndrome. Study Design: - Single descriptive case study. Place: - Baqai university hospital Township Lahore. Materials and Method: - A 39-year-old patient presented at 26 weeks of gestation for routine obstetric scan. Prenatal sonographic examination was commenced on Toshiba Xario 100 ultrasound machine using a 3-5 MHz curved-array transducer. Trans-abdominal scan was performed. Fetal growth parameters and amniotic fluid volume were measured. Fetal anatomy was assessed for congenital anomalies. Amniotic fluid cells sample was obtained to carry out prenatal cytogenetic analysis. Results: - Antenatal ultrasound scan revealed a single intrauterine active male fetus with over- distended stomach and duodenum giving rise to a “double-bubble sign” and associated mild polyhydramnios was noted indicating duodenal atresia. Suspicion of Down syndrome was raised. Prenatal cytogenetic investigation (amniocentesis) was carried out to rule out any presence of chromosomal anomalies. The test confirmed that the fetus had Down syndrome. There was confirmed association of duodenal atresia and Down syndrome in the fetus. Family decided to continue pregnancy which was managed accordingly and carefully planned intervention resulted in a live-birth. Duodenal atresia was treated surgically to improve survival rate. This immediate intervention proved beneficial. Conclusion: - Ultrasonography is a safe modality for prenatal screening. There is a known association between duodenal atresia and Down syndrome (approximately 30%) which was noted in our study. Duodenal atresia reveals a typical “double-bubble sign” on prenatal ultrasonography. Awareness of this prenatal sonographic finding should result in improved detection of Down syndrome and also prompt a cytogenetic investigation which will aid to identify, plan and direct the management of fetuses at risk of Down’s syndrome. KEYWORDS: - Ultrasonography, Duodenal Atresia, Down Syndrome, Double-Bubble Sig