Hepatic nodular regenerative hyperplasia

Liver A 48-year-old patient with Crohn s disease developed hepatic nodular regenerative hyperplasia, with fatigue, icterus, hepatosplenomegaly, and ascites, accompanied by pancytopenia fiver histology suggested a drug-induced cause and after withdrawal of azathioprine he improved substantially [128 ]. 

Similarly, in various liver diseases, thought should be given to the presence of HE if neuropsychiatric disturbances occur. This is true for acute liver diseases (severe acute viral hepatitis, acute liver failure) and for severe (particularly alcohol-related) fatty liver, Wilson s disease, severe chronic hepatitis, severe infectious or parasitic liver diseases such as schistosomiasis, metastatic liver, nodular regenerative hyperplasia, and liver cirrhosis. (1,16,17, 22, 24,28,29, 67,76,78,95,104) The diagnosis of HE can prove difficult if the liver disease is (still) unknown. 

A particular hepatotropicity causing severe herpes hepatitis is ascribed to herpesvirus 6 (HHV-6). There have even been reports of a fulminant course with this virus infection. (18, 23, 35) HHV-8 causes Kaposi s sarcoma. The liver is the most common site, with dark reddish-violet tumour nodes. Histological analysis reveals endothelial cell proliferations and growths of spindle-shaped fibroblast-like cells. The bile ducts may be altered. Transaminase levels are elevated, and jaundice occurs. There may be a causal relationship between HHV-8 infection and multicentric Castlemans disease. The latter usually implies the presence of peliosis hepatis, perisi-nusoidal fibrosis and nodular regenerative hyperplasia. 

Other histological features that have been described include lesions of the hepatic venous system (pehosis hepatis, sinusoidal dilatation, perivenous fibrosis, and nodular regenerative hyperplasia) and these can be associated with portal hypertension (SEDA-16,520) (SED-13, 1120) (21). Particularly severe and potentially fatal veno-occlusive liver disease has been reported in patients with renal and allogeneic bone marrow transplants taking chronic treatment (26) (SEDA-12, 386), but complete histological reversal can be observed (SEDA-20, 341). 

Matsumoto T, Kobayashi S, Shimizu H, et al (2000) The liver in collagen diseases pathologic study of 160 cases with particular reference to hepatic arteritis, primary biliary cirrhosis, autoimmune hepatitis and nodular regenerative hyperplasia of the liver. Liver 20 366-373 Meyers RL, Scaife ER (2000) Benign liver and biliary tract masses in infants and toddlers. Semin Pediatr Surg 9 146-155... 

Other investigators have reported cases of nodular regenerative hyperplasia demonstrating multiple hy-pervascular hepatic lesions in young patients without cirrhosis but with underlying vascular abnormalities nevertheless the nodules are usually multiple, distributed uniformly through the liver and in most cases present a peripheral ischemic rim (Motoori et al. 1997). 

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