Liver viral hepatitis

Yellow phosphorus was the first identified liver toxin. It causes accumulation of lipids in the liver. Several liver toxins such as chloroform, carbon tetrachloride, and bromobenzene have since been identified. I he forms of acute liver toxicity are accumulation of lipids in the liver, hepartxiellular necrosis, iii-trahepatic cholestasis, and a disease state that resembles viral hepatitis. The types of chrome hepatotoxicity are cirrhosis and liver cancer. 

TABLE 5.13 Examples of Drugs that Induce Intrahepatic Cholestasis or Liver Damage Resembling That Induced by Viral Hepatitis... 

Hepatitis is acute or chronic inflammation of the liver, which is frequently caused by infection with hepato-tropic viruses. Several forms of viral hepatitis (A, B, C, D, E) are known, which result from infection with viruses belonging to separate virus families, differing in their genomic organization, replication strategies, morphology and modes of transmission. 

Cirrhosis is the result of long-term insult to the liver, so damage is typically not evident clinically until the fourth decade of life. Chronic liver disease and cirrhosis combined were the 12th leading cause of death in the United States in 2002. In patients between the ages of 25 and 64, damage from excessive alcohol use accounted for over one-half of the deaths.2 Alcoholic liver disease and viral hepatitis are the most common causes of cirrhosis in the United States and worldwide. 

Infection with one or more strains of viral hepatitis often causes acute inflammation of the liver, while chronic infection with hepatitis B or C can lead to cirrhosis. Hepatitis B and C are common in intravenous drug users and can also be transmitted through sexual contact, but many cases of hepatitis C are idiopathic.5,6 Hepatitis C is a more common cause of cirrhosis than hepatitis B in the United States while hepatitis B is more common in the rest of the world.7 See Chapter 21 on viral hepatitis for a complete discussion of infectious hepatitis. 

O Prevention and treatment of viral hepatitis may prevent progression to chronic hepatitis, cirrhosis, and end-stage liver disease. 

Chronic hepatitis (disease lasting longer than 6 months) is usually associated with hepatitis B, C, and D. Chronic viral hepatitis may lead to the development of cirrhosis, which may induce end-stage liver disease (ESLD). Complications of ESLD include ascites, edema, jaundice, hepatic encephalopathy, infections, and bleeding esophageal varices. Therefore, prevention and treatment of viral hepatitis may prevent ESLD. 

Viral hepatitis can occur at any age and is the most common cause of liver disease in the world. The true prevalence and incidence may be underreported because most patients are asymptomatic. The epidemiology, etiology, and pathogenesis vary depending on the type of hepatitis and will be considered separately below. 

Diagnosing viral hepatitis may be difficult because most infected individuals are asymptomatic. Because symptoms cannot identify the specific type of hepatitis, laboratory serologies must be obtained (Table 21-2). In addition, liver function tests may be obtained to assess the extent of cholestatic and hepatocellular injury. However, the definitive test to determine the amount of damage and inflammation of hepatic cells is a liver biopsy. 

Managing viral hepatitis involves both prevention and treatment. Prevention of hepatitis A and B (and indirectly for hepatitis D) can be achieved with immune globulin or vaccines. There is no specific pharmacologic treatment for acute viral hepatitis A, B, C, D, or E only supportive care is available. Individuals with mild to moderate symptoms rarely require hospitalization. Occasionally, hospitalization is required in individuals experiencing significant nausea, vomiting, diarrhea, and encephalopathy. Liver transplantation may be required in rare instances if fulminant hepatitis develops. 

Patients with viral hepatitis B, C, and D may develop chronic disease leading to ESLD. Treatment is only available for chronic liver disease associated with HBV, HCV, and HDV.20,21... 

Idrovo, V., et al. (1996). Hepatitis C vims RNA quantification in right and left lobes of the liver in patients with chronic hepatitis C. J. Viral Hepat. 3,239-246. 

In the region with pesticide contamination where subjects contracted viral hepatitis A, the pre-jaundice period was 4.2 days (in the control area, 5.1), the jaundice period lasted 32 days (22.4 in the control area), the liver enlarged more than in the control area and took longer to return to normal size, there was a larger number of patients who also had an enlarged spleen, there was more frequent damage to the nervous and cardiovascular systems (1.5-2 times higher than in the control area), mixed syndrome was observed more often (45% of the time, compared to 12.6% in the control area), and the illness was more frequently serious. 

Ongoing clinical trials continue to assess the efficacy of recombinant interferon preparations in treating a variety of cancers. Some trials suggest that treatments are most effective when administered in the early stages of cancer development. rhIFN-as have also proven effective in the treatment of various viral conditions, most notably viral hepatitis. Hepatitis refers to an inflammation of the liver. It may be induced by toxic substances, immunological abnormalities, or by viruses (infectious hepatitis). The main viral causative agents are ... 

Influence of Grinization Complex on Different Functions of the Liver in Patients with Viral Hepatitis... 

Thus, influenza virus A/PR/8/34(HlNl) is present in the liver of infected mice of both groups and is eliminated by the end of experiment. Infected animals demonstrate persistent changes in the liver which can be estimated as viral hepatitis manifestations. In spite of influenza virus... 

MLL4 (KMT2D) Involvement in viral (hepatitis B) liver carcinogenesis [92] H3K4... 

Many patients have underlying liver disease with liver function abnormalities. It may be difficult to determine superimposed drug-induced liver injury in patients with viral hepatitis, passive congestion of the liver from heart failure, fatty liver... 

Milk thistle has shown promise in improving liver function parameters in various hepatotoxic situations, such as alcoholic cirrhosis and mushroom poisoning. It is still unclear whether it will offer protection against viral hepatitis and various nephrotoxic agents. 

Contraindications Active alcoholism, liver disease, or viral hepatitis, all of which increase the risk of hepaf ofoxicity... 

Hepatitis C virus (HCV) is an RNA virus that is a common cause of parenterally acquired viral hepatitis chronic infection follows acute infection in 80% to 85% of cases. Although liver disease resulting from chronic HCV infection is only slowly progressive, HCV is the most common cause of chronic liver disease in the United States, the most common etiology for hepatocellular carcinoma, and the leading indication for liver transplantation [34-36]. 

Hoofnagle,J.H.,andA.M.DiBisceglie,5 erc>-logic diagnosis of acute and chronic viral hepatitis. Semin Liver Dis, 1991.11 73-83. 

CBZ can cause a mild, transient increase in serum transaminases and alkaline phosphatase levels. They usually do not exceed 1.5 times normal levels and subside with ongoing treatment. If liver function tests (LFTs) increase two to three times normal levels, hepatotoxicity may result. With prolonged CBZ therapy, a syndrome resembling a mild viral hepatitis may occur but usually improves after drug discontinuation. 

Acquired hyperammonemia Liver disease is a common cause of hyperammonemia in adults. It may be a result of an acute po cess, for example, viral hepatitis, ischemia, or hepatotoxins. Cirrhosis of the liver caused by alcoholism, hepatitis, or biiary obstruction may result in formation of collateral circulation around the liver. As a result, portal blood is shunted directly rto the systemic circulation and does not have access to the ter. The detoxification of ammonia (that is, its conversion to urea) is, therefore, severely impaired, leading to elevated levels of cicu lating ammonia. 

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