[1436] Histopathology of Idiopathic Portal Hypertension in Patients with HIV Infection Treated with HAART

R Miquel, P Chang, JL Blanco, M Laguno, J Gonzalez-Abraldes, J Bosch, JC Garcia-Pagan, M Bruguera. Hospital Clinic, IDIBAPS, UB, Barcelona, Spain

Background: Idiopathic portal hypertension (IPH) describes the clinical entity of pre-sinusoidal portal hypertension in the absence of cirrhosis and other known etiologies of liver dysfunction. Patients with IPH often have preserved liver function but present with symptoms of portal hypertension, mainly variceal bleeding, splenomegaly and thrombocytopenia. The histological features associated with IPH involve a wide spectrum of non-specific changes, being the key feature the absence of cirrhosis. Recently, several cases of IPH in patients with Human Immunodeficiency Virus (HIV) infection have been reported.
Design: The aim of this study is to examine the histological profile of liver biopsies in HIV patients who presented with IPH.
Results: A total of eight HIV patients on HAART were identified over the last three years. Five presented with variceal bleeding, one with ascites and two with radiologycal and endoscopic features of IPH. Portal and systemic hemodynamics showed normal or mildly elevated hepatic venous pressure gradient in 6 patients and intrahepatic vascular shunts in 5. Viral hepatitis, autoimmunity, alcohol abuse, genetic and metabolic disorders and underlying thrombophilic abnormalities were excluded. Fourteen liver biopsies from these patients were reviewed (5 percutaneous, 9 transjugular). Cirrhosis was not present, and 12 out of 14 biopsies showed Metavir F0/F1. Absence of a patent portal vein radical (PVR) was a constant finding in all biopsies, with a variable degree of portal tract involvement. In 6 patients PVR was absent in more than 50% of portal tracts, and all biopsies had a percentage of portal tracts without PVR above 30%. Occasionally, other PVR changes such as phlebosclerosis or herniation were identified. Abnormal periportal vascular channels, focal sinusoidal dilatation and perisinusoidal fibrosis were identified in 8 biopsies each. Foci of regenerative hepatocytes were present in all biopsies, being in places vaguely nodular. No significant inflammation or steatosis was observed.
Conclusions: HIV-related IPH is characterized histologically by a heterogeneous spectrum of lesions. The most consistent finding is the presence of abnormal portal vein radicals, which may be interpreted as a progressive vascular obliterative disorder. The etiology remains elusive, and potential agents such as endothelial injury, related to drug toxicity or cytokine-induced damage, deserve further studies.
Category: Liver & Pancreas

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 163, Tuesday Morning