Abstract
Hepatic inflammatory pseudotumor (HIPT) is an uncommon lesion of unclear etiology, and variable clinical manifestations. Here we report a case of HIPT with extensive venous thrombosis. A 58-year-old Caucasian male with multiple liver lesions diagnosed as hepatic inflammatory pseudotumor and recurrent venous thrombosis resulting in recurrent gastroesophageal variceal bleeding. Sixteen-year prior, he had infectious mononucleosis and liver biopsy for persistent jaundice showed granulomatous hepatitis (non-necrotizing micro granulomas within lobules) without significant fibrosis. The portal areas were markedly expanded by mixed inflammation and also had diffuse sinusoidal histiocytic infiltration. Ten years later, he developed recurrent venous thrombosis and esophago-gastric varices without increased hepatic venous pressure gradient. Hyper-coagulopathy work-up was negative. Imaging showed multiple liver lesion concerning for metastatic lesions vs liver abscess (Fig 1). Biopsy of these lesions showed numerous histiocytes, dese spindled myofibroblast proliferation with mixed inflammation, intrahepatic thrombi suggestive of hepatic inflammatory pseudotumor and left untreated. A follow-up MRI showed interval resolution of hepatic lesions. A year later, he developed large hepatic abscess and new venous thrombosis; blood culture grew streptococcus intermedius bacteremia and new multifocal enhancing liver lesions demonstrating restricted diffusion, measuring upto 10 cm were noted on MRI (Fig 1,2). Frank pus was drained of these lesions and cytology was negative for malignancy. Follow-up MRI at 4 weeks showed marked decrease in size of lesions with near complete resolution central necrotic area (Fig 1). HIPT believed to be a low-grade fibro sarcoma with inflammatory cells with rare malignant progression. Responses to surgical aggression or trauma or Epstein-Barr virus infection are considered possible etiologies. Local occlusive phlebitis of the portal vein has been described as a possible complication of inflammatory pseudotumor of the hepatic hilum , explained by the activation of the procoagulant activity of the vascular endothelium by inflammatory mediators. This case suggests possible EBV infection as etiology, waxing and waning liver lesions, associated extensive venous thrombosis and micro thrombosis serving as nidus for abscess formation in setting of bacteremia.