Hepatic fibrosis produced in guinea pigs by chronic ethanol administration and immunization with acetaldehyde adducts.

Experimental hepatic fibrosis was produced in the guinea pig. We produced hepatic necrosis associated with inflammatory cell infiltration in guinea pigs immunized with acetaldehyde adducts and fed ethanol for 40 days. Extending the period of these treatments to 90 days resulted in producing hepatic fibrosis developing around individual hepatocytes in the terminal hepatic venule areas and portal areas, accompanied by an increase in hepatic hydroxyproline content. In contrast, no fibrosis was observed in the livers of the control groups that had been exposed to nothing, ethanol alone, or a combination of ethanol and immunization with unmodified human hemoglobin. Minimal fibrotic changes were observed in animals immunized with human hemoglobin acetaldehyde adducts but not fed ethanol. These results indicate that the formation of acetaldehyde adducts and the acquisition of immunity against them can produce hepatic fibrosis. Immune mechanisms against acetaldehyde adducts may, in part, be involved in the pathogenesis of hepatic fibrosis seen in alcoholics.

Relationship between hepatitis C virus subtypes and clinical features of liver disease seen in alcoholics.

The influence of hepatitis C virus and its subtypes on the clinical course of liver disease in alcoholics was assessed. Hepatitis C virus infection was confirmed by a reverse transcription and polymerase chain reaction method for the hepatitis C virus NS-5 region in the sera of alcoholics with various stages of histologically proven liver disease. The frequency of hepatitis C virus was significantly higher in alcoholics with chronic hepatitis (73%) than in those with liver fibrosis (18%), alcoholic hepatitis (17%), and fatty liver (0%). Hepatitis C virus subtypes, namely K1 and K2, were determined by dot-blot hybridization analysis of the polymerase chain reaction products with specific probes, and their frequencies were 68% and 32%, respectively. The proportion of patients whose serum transaminase levels returned to normal following 4 weeks of abstinence in hospital was significantly lower in alcoholics with hepatitis C virus viremia (glutamic oxaloacetic transaminase: 53.8%; glutamic pyruvic transaminase: 42.3%) than in those without viremia (glutamic oxaloacetic transaminase: 86.2%, p < 0.01; glutamic pyruvic transaminase: 89.7%, p < 0.01). When alcoholics with the K1 and K2 subtypes of hepatitis C virus were compared, normalization of transaminase levels was less frequent in alcoholics with K1 (glutamic oxaloacetic transaminase: 42.8%; glutamic pyruvic transaminase: 28.6%) than in those with K2 (glutamic oxaloacetic transaminase: 88.9%, p < 0.05; glutamic pyruvic transaminase: 77.8%, P < 0.05). These data indicate that hepatitis C virus infection is associated with a reduced rate of recovery of serum transminase levels following abstinence in subjects with alcoholic liver disease, more so in the K1 subtype than in the K2 subtype.

[Definition and classification of liver cirrhosis].

The clinical features of liver cirrhosis are manifestation of altered hepatic hemodynamics and of reduced hepatic cell mass, represented by portal hypertension and sometimes hepatic failure. Histologically, cirrhosis is defined in general as a diffusely altered reconstruction of the lobular parenchyma with widespread connective tissue septa, which circumscribe regenerative nodules of the hepatocytes and contain anastomoses between efferent as well as afferent vascular systems linking central and portal canals. Thus, a large portion of portal blood flow bypasses the hepatocytes and reticuloendothelial cells, depleting them of their metabolic and detoxifying function. It is often impossible to make a morphologic classification of liver cirrhosis based on tiny biopsy specimens, and the histologic criteria are neither specific nor mutually exclusive. Furthermore, a frequent lack of correlation between the etiologic and morphologic types of cirrhosis has led the clinicians to classify the cirrhosis based on the main etiologic factor. According to the statistics (1991) of 40 representative medical institutes in Japan, covering approximately 8,600 liver cirrhosis cases, 16.9% of the cirrhosis is supposedly due to type B hepatitis virus infection, 54.9% to type C, 10.7% to alcoholic abuse and the remainder are of unknown etiology. It would be reasonable to apply the etiologic classification to liver biopsy specimens and morphologic classification to autopsy materials for thorough examination.

Experimental hepatitis induced by ethanol after immunization with acetaldehyde adducts.

We produced hepatitis in guinea pigs by immunization with acetaldehyde adducts and ethanol treatment. Human hemoglobin-acetaldehyde adducts were prepared without any reducing agents and affinity purified with polyclonal antibodies against acetaldehyde adducts. Female guinea pigs were immunized with the adducts and were simultaneously given ethanol for 40 days. These treatments induced hepatic necrosis with infiltration of mononuclear cells in the hepatic lobules. The formation of the lymphoid follicle was also observed in severe cases. These changes were accompanied by the elevation of serum AST and lactic dehydrogenase activities and titers of circulating antibodies against acetaldehyde adducts. By contrast, the combination of ethanol and immunization with unmodified hemoglobin produced only fatty change of the liver, and animals immunized with the adducts alone had minimal inflammatory changes of the liver. Peripheral blood lymphocytes obtained from the animals with hepatitis were shown to be stimulated by acetaldehyde adducts to a significantly greater degree than those from control animals who received nothing, ethanol alone or ethanol and unmodified hemoglobin. These results suggest that the immune response to acetaldehyde adducts may be involved, at least partly, in the pathogenesis of inflammation observed in alcoholic liver disease.

[A case of miliary tuberculosis presenting as fever and jaundice with hepatic failure looking like the course of fulminant hepatitis].

A 79-year-old male was admitted to the Metropolitan Hiroo Hospital with chief complaints of icterus and fever. A few weeks prior to admission, he developed fever and swelling of right side of the neck and was seen at a local hospital where an anti-inflammatory agent was prescribed. The fever subsided in a few days, but recurred together with development of icterus a few weeks later, precipitating this hospitalization. After admission, hepatic failure progressed rapidly, indicating a fulminant hepatitis. Renal failure also developed and he died. Autopsy revealed diffuse caseous necrosis with demonstration of acid-fast bacilli in the liver, as did in the spleen, kidney and bone marrow. This case epitomizes a subset of miliary tuberculosis in which the hepatic failure predominates the clinical presentation while lacking the ante-mortem chest X-ray features suggestive of pulmonary tuberculosis and post-mortem macroscopic changes indicative of tuberculosis.

Different appearance of hepatic collagenase and lysosomal enzymes in recovery of experimental hepatic fibrosis.

1. Both activities of hepatic collagenase and lysosomal enzymes (acid phosphatase, beta-glucuronidase and N-acetyl-beta-D-glucosaminidase) have been observed in the recovery from experimental hepatic fibrosis in rats treated with carbon tetrachloride for 6 to 20 weeks, and compared with the disappearance of newly formed collagen fibers in the recovery process. 2. In the process of experimental hepatic fibrosis, collagenase activity reached maximum on sethe accumulation of collagen fibers in reversible hepatic fibrosis, but decreased to the same level as that of non-treated rat liver in cirrhotic stage. In the reocvery from reversible hepatic fibrosis, collagenase activity reached maximum on second day after the discontinuation of carbon tetrachloride, and decreased to the same extent of that of non-treated rat liver on seventh day. 3. Lysosomal enzyme activity was parallel to the activity of hepatic collagenase and to the accumulation of collagen fibers in the process of hepatic fibrosis. In the recovery stage, lysosomal enzyme activity in mesenchymal cells within the septa increased markedly on second day after the discontinuation of toxic agent but turned to the same level of that of non-treated rat liver seven days later, which was consistent with the appearance and disappearance of collagenase activity. On the other hand the appearance of lysosomal enzymes activities in Kupffer cells and hepatocytes was different from that of collagenase activity. That is lysosomal enzyme activity in Kupffer cells decreased in early days but increased five days later, and the enzyme activity in hepatocytes markedly decreased but gradually recovered to normal level seven days later. 4. The appearance of collagenase was observed at the beginning of the recovery stage. It indicates that mammalian collagenase initiates the collagen degradation and lysosomal enzymes might have a role in the subsequent degradation of collagen.