LOBAR ATROPHY CAUSED BY COMBINED PORTAL AND HEPATIC VEIN THROMBOSIS IN CHILDREN

Abstract

188 Structural and functional integrity of the liver parenchyma is dependent on intact vascular supply. Non-cirrhotic portal hypertension results from hepatic vascular injury: among its various etiologies, portal vein thrombosis with cavernous transformation of the portal vein is most common in children. Hepatic vein thrombosis causes severe parenchymal injury but is much less common in the pediatric age group. We hypothesize that combined portal vein and hepatic vein thrombosis would lead to significant macroscopic loss of liver parenchyma. We describe this condition in three children. Patient 1: 17 year-old male with eosinophilic vasculitis developed acute Budd-Chiari syndrome with liver failure followed by superior mesenteric arteritis with bowel infarction several days later. After recovery, sonography, showed persistent thrombosis of R hepatic vein and R portal vein branches, with very small R lobe of liver and an enlarged L lobe. No clinically significant portal hypertension in 7 years' follow-up. Patient 2: 4 year-old male had bilateral pleural effusions at birth requiring prolonged perinatal hospitalization with umbilical vein catheterization; a clot in the inferior vena cava (IVC) was found on day 11 of life. Subsequent sonography disclosed segmental thrombosis of L portal vein, small L hepatic vein, and small L lobe of liver and enlarged R lobe. Asymptomatic in 4 years' follow-up. No evidence of thrombotic tendency. Patient 3: 7 year-old female with congenital heart disease and asymmetric leg length was incidentally found to have abnormal hepatic findings on sonography. MR showed absent L portal vein, absent or markedly hypoplastic L lobe, and abnormal confluence and course of hepatic veins; IVC was patent. Asymptomatic before diagnosis and after 1 year's follow-up. Summary: Combined loss of vascular outflow and inflow to a single lobe leads to lobar atrophy. Clinically-significant portal hypertension may not develop. Since hepatic vein thrombosis causes parenchymal extinction, it is likely the dominant lesion. This may be a benign variant of Budd-Chiari syndrome in children.