Fibrosis perivenous

Central venules only contain a small amount of collagen, with the result that in this form of fibrosis, perivenous sinusoids are always involved as well. A typical example is perivenular fibrosis in chronic alcohol abuse, (s. fig. 21.16) Centrolobular fibrosis may also be detectable in healed viral hepatitis or following slight liver damage (e.g. Meulengracht s disease). Central hyaline sclerosis, which is due to chronic alcohol abuse with intermittently recurring alcohol hepatitis, is known to be a particularly severe form of fibrosis, (s. p. 526)... 

Alcoholic hepatitis also leads to a postsinusoidal block following the deposition of alcoholic hyaline in the centrilobular zone, with perivenous fibrosis and subsequent occlusion of the small veins. 

Primary pulmonary diseases (e.g. primary pulmonary hypertension, pulmonary fibrosis, chronic obstructive respiratory diseases) cause chronic hepatic congestion due to chronic pulmonary heart disease, possibly leading to insufficiency. Hypoxaemia as a result of acute or chronic respiratory insufficiency can impair metabolic liver functions considerably. In 40—70% of patients with cirrhosis, hypoxaemia can be found in about 50% of cases with advanced cirrhosis, a reduced diffusion capacity for CO is detectable. Furthermore, pulmonary tissue contains a high level of glutamine synthetase, so that ammonia detoxification is possible (ultimately by perivenous hepatocytes) before the blood reaches the systemic circulation. In existing pulmonary diseases, localized ammonia detoxification is impaired. 

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). 

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