Development of portal vein thrombosis complicating idiopathic portal hypertension. A case report.

A 58-yr-old woman with biopsy-proven idiopathic portal hypertension presented with ascites and pretibial pitting edema. On admission, ultrasonic Doppler flowmetry demonstrated hepatopetal flow of a markedly reduced velocity in the portal vein, hepatofugal flow in the splenic vein, and a large spontaneous splenorenal shunt. The patient spontaneously developed hepatic encephalopathy 1 mo later. Percutaneous transhepatic portography demonstrated mural thrombi at the porta hepatis after the catheter had penetrated the mural thrombi without resistance; there was also a long retention of contrast medium in the portal vein. 99mTc-Macroaggregated albumin instilled into the superior mesenteric vein was caught in the lungs, and no activity entered the liver. Measurements of ammonia and immunoreactive insulin clearly indicated that superior mesenteric venous blood was shunted through the splenic vein and the splenorenal shunt. Subsequent ultrasonic examination with Doppler flowmetry suggested further growth of the thrombi and lack of blood flow in the portal vein. Although the procedure of percutaneous transhepatic catheterization could have contributed to the growth of thrombi, it is more likely that the thrombosis in the portal vein was a sequela to idiopathic portal hypertension, and was growing at the time of catheterization. This case may be of significance in the understanding of the relationship between idiopathic portal hypertension and extrahepatic portal obstruction.