EP07.39: An isolated fetal pericardial effusion

An isolated fetal pericardial effusion (PE) is commonly observed on routine obstetric scans. The significance and the exact incidence of PE is not yet clear. The perinatal outcome in such cases depends on the presence or otherwise of associated malformations and chromosomal anomalies. We report a case which has been diagnosed at 16 weeks with an isolated pericardial effusion at 16 weeks in 29-year-old Gravida 3, para two. No associated abnormalities were detected. Her blood group is A Rhesus positive. The patient gave a history of upper respiratory tract infection in the early first trimester and received an intravenous antibiotic. She was immune to rubella and serology for hepatitis B and HIV, all of which were negative. The fetal infectious screen was negative for toxoplasmosis and cytomegalovirus. Also, the anti-phospholipid antibodies were negative. On ultrasound scanning, at 16 weeks, both lungs were compressed by large PE. Follow-up scans at 19 and 22 weeks showed a slight reduction of PE, and both lungs showed a slight expansion. At 24 weeks, on a detailed scan, there was a significant reduction of PE with the remaining effusion thickness at 3mm with normal fetal echocardiography and no congenital anomalies were detected. On rescanning at 26 weeks showed a complete resolve of PE, and the pregnancy progressed smoothly and ended with normal vaginal delivery at the term of a male baby weighing 3.8kg; Apgar scores were 9, 10 at 1, and 5 minutes, respectively. The neonatal outcome was good, and the echocardiography was normal. Most cases of isolated PE resolved spontaneously and were associated with a good prognosis.