A RARE CAUSE OF ABDOMİNAL PAİN: CONGENİTAL EXTRAHEPATIC PORTOCAVAL SHUNT - ABERNETHY MALFORMATION TYPE 2

H. ERDAL, İ. DOĞAN, O. G UTKU, M. İBİŞ, M. ARHAN,

S. ÖZENİRLER, S. ÜNAL

Gazi University School of Medicine, Ankara, TURKEY

Congenital extrahepatic portocaval shunts are classified into 2 types: one is congenital absence of the portal vein (side-to-end anastomosis, Abernethy type 1 shunt) and the other is a shunt composed of a side-to-side anastomosis with hypoplastic portal blood flow into the hepatic parenchyma (Abernethy type 2 shunt). Each type of shunt is associated with a clinical presentation of type 1 usually are seen in girls and often complicated with cardiac anomalies and a hepatic mass including hepatoblastoma, hepatocellular carcinoma, focal nodular hyperplasia (FNH), and hepatocellular adenoma. Type 2 shunts usually are acquired in cirrhotic livers, and the congenital extrahepatic type is far less common. Type 2 congenital extrahepatic shunts are often seen in men and seldom complicated with other anomalies. This type of shunt tends to be diagnosed as the cause of hepatic encephalopathy and severe liver dysfunction.

Case report: A 20-year-old man was referred to our hospital with abdominal pain. A year before this admission, he began to feel abdominal pain , usually it has started after meals and vomiting-nause no exist. On examination, his abdomen was soft and slightly tenderness in right upper quadrant. Laboratory studies revealed cell blood count, renal function, liver function, electrolytes level, serum albumin, and total bilirubin level were normal. Contrast enhenced magnetic resonans imaging of abdomen revealed normal size and paranchimal heterogenity of liver, multiple arteriovenous shunt in segment 4-5-6-7 and 8.

Truncus coliacus, superior mesenteric arter and hepatic arter marked dilatation where the biggest size is 10 mm. Main portal vein 16 mm, right portal vein 20 mm and marked dilated. Right portal vein is related to vena cava inferior at superior of truncus coliacus. Distal left portal vein is unvisualized.

Discussion: Congenital extrahepatic portosytemic shunts (CEPS) are rare occurrences and were first described by Abernethy over 200 years ago . In type 1 anomalies, there is absence of the intrahepatic portal vein and all portal venous blood drains into the IVC. Malformations with side-to-side portocaval shunts and intact portal vein constitute type 2 anomalies. The scope for development of these malformations arises from the unique embryological derivation of the portal venous system and the IVC.

Both malformations, however, predispose to the development of hepatic encephalopathy due to diversion of portal flow into the systemic circulation and subsequent hyperammonemia. Treatment of these conditions is frequently directed at management of associated conditions and encephalopathy. Liver transplantation is a definitive treatment for type 1 lesions because shunt occlusion is contraindicated due to the absence of intrahepatic portal vein. Type 2 lesions lend themselves amenable to surgical shunt division which can be performed by open or laparoscopic means. The long-term prognosis of CEPS is dependent on the presence and course of associated anomalies as well as the severity of liver disease and shunting.Long-term follow-up with clinical, biochemical, and imaging evaluation is recommended to screen for development of liver tumors and portal hypertension, especially in type 1 anomalies.

Date: 2014-12-28; view: 773