Hepatic siderosis in extrahepatic portal vein obstruction. Role of spontaneous portosystemic shunting?

We report on the observation of a 26-year-old woman with portal vein obstruction, diagnosed at the age of 3, and liver iron overload. Celiac and superior mesenteric angiography showed large and multiple venous collaterals between the portal and caval systems. Liver biopsy demonstrated, on Perl's staining, an important hemosiderin deposition, confirmed by an increased hepatic iron concentration (15.6 mumol/100 mg dry weight). No other histologic abnormality was found. This report suggests that large spontaneous portosystemic shunting may stimulate hepatic iron deposition in an otherwise normal liver. This mechanism could, at least in part, explain the significant hepatic siderosis observed in some cirrhotic patients.