Ischaemic hepatitis

Hepatic reperfusion injury is not a phenomenon connected solely to liver transplantation but also to situations of prolonged hypoperfusion of the host s own liver. Examples of this occurrence are hypovolemic shock and acute cardiovascular injur) (heart attack). As a result of such cessation and then reintroduction of blood flow, the liver is damaged such that centrilobular necrosis occurs and elevated levels of liver enzymes in the serum can be detected. Particularly because of the involvement of other organs, the interpretation of the role of free radicals in ischaemic hepatitis from this clinical data is very difficult. The involvement of free radicals in the overall phenomenon of hypovolemic shock has been discussed recently by Redl et al. (1993). More specifically. Poll (1993) has reported preliminary data on markers of free-radical production during ischaemic hepatitis. These markers mostly concerned indices of lipid peroxidation in the serum and also in the erythrocytes of affected subjects, and a correlation was seen with the extent of liver injury. The mechanisms of free-radical damage in this model will be difficult to determine in the clinical setting, but the similarity to the situation with transplanted liver surest that the above discussion of the role of XO activation, Kupffer cell activation and induction of an acute inflammatory response would be also relevant here. It will be important to establish whether oxidative stress is important in the pathogenesis of ischaemic hepatitis and in the problems of liver transplantation discussed above, since it would surest that antioxidant therapy could be of real benefit. 

As stated at the beginning of this article, the liver is the most intensively studied animal tissue in biochemistry. In the context of the role of free radicals in human diseases, the liver is not obviously at centre stage, since heart disease and cancer are more important in the industrialized world than, for example, cirrhosis. Free-radical biochemistry of the liver will remain a fertile area of work, however, not least because so many original ideas and techniques are developed there and then applied to the study of other tissues. The increasing use of liver transplantation, following the acceptance of kidney and heart transplants as almost routine, will surely increase the interest in the study of ischaemia-reperfusion injury in 

I would like to dedicate this paper to all of my colleagues at the Institute of General Pathology in Turin, who have made such important contributions to this subject, and have been such consistent and generous friends for so long. Forza Toro. 

Albano, E., Lott, K.A.K., Slater, T.F., Stier, A., Symons, M.C.R.and Tomasi, A. (1982). Spin trapping studies on the free radical products formed by metabolic activation of carbon tetrachloride in rat liver microsomal fractions, isolated hepato-cytes and in vivo in the rat. Biochem. J. 204, 593-603. 

Albano, E., Tomasi, A., Goria-Gatti, L. and Dianzani, M.U. (1988). Spin trapping of free radical species produced during the microsomal metabolism of ethanol. Chem. Biol. Interact. 65, 223-234. 

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Iron Overload and Liver Injury 238 3.10 Ischaemic Hepatitis 243... 

Berry P. Severe congestive cardiac failure and ischaemic hepatitis associated with rosiglitazone. Pract Diabetes Int 2004 21 199-200. 

Hickman P, Potter J. Mortality associated with ischaemic hepatitis. Aust N Z J Med 1990 20 ... 

Outside the liver the common hepatic duct is joined by the cystic duct of the gallbladder and becomes the common bile duct (CBD). The extrahepatic and intrahepatic ducts are supplied with blood by a fine network of tiny arterial branches that originate from the hepatic and gastroduodenal arteries. As it has no other blood supply, the biliary tree is particularly susceptible to ischaemic injury, such as hepatic artery thrombosis or injury to the biliary plexus during laparoscopic surgery. This can result in extrahepatic and complex hilar and perihilar ischaemic strictures of the biliary tree. 

Occlusion of the hepatic artery is responsible for a 50% reduction in oxygen supply. Even if an unimpaired oxygen supply via the portal vein is guaranteed, arterial occlusion usually causes ischaemic infarction. The clinical and morphological pictures are characterized (1.) by the speed with which an occlusion develops and (2.) by the presence of variants that can be used as a bypass or of collaterals that have already been established in gradual vascular occlusion. This results in a broad clinical spectrum, which may range from a symptom-free condition to liver hypoxia, including infarction up to hepatic coma. 

Ischaemic colitis After 19 weeks of treatment with pegylated IFNa-2a and ribavirin for chronic hepatitis C genotype lb, a 48-year-old woman developed severe abdominal pain with haematochezia. CT, colonoscopy and colonic mucosal biopsy led to a diagnosis of ischaemic colitis. After discontinuation of the IFN-ribavirin therapy, the symptoms subsided and mucosal ulceration improved. A munber of cases of ischaemic colihs during IFN therapy have been reported, all of which involve the descending colon [46 ]. 

Two further cases of ischaemic colitis dining IFN treatment of chronic hepatitis C were fully healed within 1 week after symptoms onset and withdrawal of pegylated lFNa-2b. Upon resumption of IFN therapy, ischaemic colihs did not recur and a sustained anhviral response was maintained in both pahents [47 ]. 

Kawaguchi T, Ide T, Itou M, Suetsugu M, Yoshioka S, Sakata M, et al. Ischaemic colitis during interferon treatment for chronic hepatitis C report of two cases and literature review. J Viral Hepat 2012 19(2) e220-4. 

SaUc A, Stobaugh DJ, Deepak P, Ehrenpreis ED. Ischaemic colitis with type I interferons used in the treatment of hepatitis C and multiple sclerosis an evaluation from the food and drug administration adverse event reporting system and review of the literature. Ann Pharmaco-ther 2013 47(4) 537.A2. 

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