Role of ultrasonography in early diagnosis of congenital extrahepatic portosystemic shunt

A 1-year-old male presented to our unit for ultrasonography of the abdomen with a history of fever and diarrhoea for 2 days. The clinical examination was normal. Ultrasound of the abdomen showed a small portal vein and splenomesenteric venous shunt into the left renal vein that was consistent with a Type II congenital extrahepatic portosystemic shunt (CEPS). Doppler sonography confirmed the flow towards the left renal vein. No abnormal findings were observed in the liver and rest of the abdominal organs. CEPS is an uncommon anomaly in which the portomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial shunt. It is usually diagnosed incidentally during investigation for other causes. Morgan and Superina (Congenital absence of the portal vein: two cases and a proposed classification system for portasystemic vascular anomalies. J Pediatr Surg 1994; 29: 1239–41) proposed a classification for these shunts in 1994 that divided these anomalies into two types. In Type I CEPS, the intrahepatic portal venous supply is absent, whereas in Type II, the intrahepatic portal venous supply is preserved. This case highlights the role of ultrasonography in the early diagnosis of CEPS.