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Essentials of Diagnosis
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General Considerations
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Causes include
Extrahepatic portal vein obstruction (portal vein thrombosis often with cavernous transformation [portal cavernoma])
Splenic vein obstruction (presenting as gastric varices without esophageal varices)
Schistosomiasis
Nodular regenerative hyperplasia
Arterial-portal vein fistula
Risk factors for portal vein thrombosis
Oral contraceptive use
Pregnancy
Chronic inflammatory diseases (including pancreatitis)
Injury to the portal venous system (including surgery)
Hepatocellular carcinoma and other malignancies
Treatment of thrombocytopenia with eltrombopag
Idiopathic noncirrhotic portal hypertension
Portal vein thrombosis
"Obliterative portal venopathy" is used to describe primary occlusion of intrahepatic portal veins in the absence of cirrhosis, inflammation, or hepatic neoplasia
Cases of noncirrhotic portal hypertension due to nodular regenerative hyperplasia have been reported in HIV-infected patients treated with didanosine or with a combination of didanosine and stavudine or didanosine and tenofovir
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Acute portal vein thrombosis usually causes abdominal pain
Aside from splenomegaly, physical examination is unremarkable
Hepatic decompensation can follow severe gastrointestinal bleeding and intestinal infarction may occur when portal vein thrombosis is associated with mesenteric venous thrombosis
Ascites may occur in 25% of persons with noncirrhotic portal hypertension
Low-grade hepatic encephalopathy is common in patients with noncirrhotic portal vein thrombosis
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Complete blood count may reveal thrombocytopenia and other findings of hypersplenism
Liver chemistries are usually normal
An underlying hypercoagulable state is found in many noncirrhotic patients with portal vein thrombosis in the absence of an obvious provoking factor
Malignant vascular invasion is suggested by a serum alpha-fetoprotein level > 1000 ng/dL (10 mcg/L), venous expansion enhancement of the thrombus, neovascularity, and proximity to a primary hepatocellular carcinoma
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