CHAPTER 18
Cirrhosis of the Liver
Arun B. Jesudian, MD
Cirrhosis of the liver is defined as the destruction of normal hepatic architecture through fibrosis and nodular regeneration. It is the eighth leading cause of death in the United States, and thus it is important for the primary care provider to be able to formulate a comprehensive, collaborative plan to provide high-quality care in a cost-effective and efficient manner (Manos, Leyden, Murphy, Terrault, & Bell, 2008). This chapter focuses on the comprehensive approach used by the primary care provider in caring for patients with cirrhosis.
ANATOMY, PHYSIOLOGY, AND PATHOLOGY
The liver weighs approximately 1,500 g. There are two anatomic lobes, the right one about six times the size of the left. The liver participates in multiple functions essential to life, including storage and metabolism of carbohydrates and detoxification of toxins. The clinical sequelae of cirrhosis result from necrosis and regeneration of liver cells, followed by an increase in fibrous tissue formation. The normal structure of the hepatic lobules is distorted, leading to impaired hepatocellular function, obstruction of bile flow through the liver, and alterations in hepatic blood flow.
Although the mechanism of cirrhosis is unknown, its etiology is diverse and extensive. It may be classified into two major categories: hepatocellular and cholestatic liver diseases. This is illustrated in Table 18.1.
EPIDEMIOLOGY
Cirrhosis is the third leading cause of death in persons between 45 and 64 years of age (Manos et al., 2008). There is no clear gender predominance. The majority of cirrhosis in the United States is caused by chronic infection with hepatitis C virus (HCV) and alcohol abuse (Garcia-Tsao & Lim, 2009). The incidence of cirrhosis secondary to nonalcoholic fatty liver disease leading to steatohepatitis has increased dramatically over the past several years. Other causes of cirrhosis are seen far less frequently in the United States.
DIAGNOSTIC CRITERIA
A definite diagnosis of cirrhosis and its etiology can usually be made by a liver biopsy demonstrating characteristic histological changes in conjunction with serological tests and viral markers. Various serological tests are useful as initial diagnostic measures, especially in patients with chronic hepatitis. A liver biopsy might not be required if a patient has physical examination, laboratory, and imaging findings consistent with cirrhosis along with diagnostic serological testing that determine the etiology of cirrhosis.
HISTORY AND PHYSICAL EXAMINATION
History
Patients with cirrhosis range from the asymptomatic, otherwise healthy patient to the patient presenting acutely with hepatic decompensation. However, more typical is the patient presenting with symptoms of fatigue, anorexia, insomnia, or pruritus of varying degrees. A detailed history is essential because it may point toward the etiology of the cirrhosis. Specific questions must be asked regarding history of alcohol intake and risk factors for acquiring viral hepatitis, such as transfusion of blood products, history of intravenous drug abuse, sexual behavior, occupational hazards (e.g., health care worker), and birthplace or travel in endemic areas. A family history of liver diseases is helpful in diagnosing diseases such as hemochromatosis and Wilson’s disease. Obtaining a past medical or surgical history is warranted because associated extrahepatic diseases can often suggest the possibility of a liver disease. The presence of inflammatory bowel disease in patients with abnormal liver chemistry results can lead to investigation of possible primary sclerosing cholangitis. Patients with decompensated liver diseases may have jaundice, confusion or insomnia, increased abdominal girth or peripheral edema, or a history of gastrointestinal bleeding.
HEPATOCELLULAR DISEASES |
Alcohol Hepatotropic viruses Hepatitis B Hepatitis C Hepatitis D Drugs and toxins Autoimmune hepatitis Right-sided heart failure Nonalcoholic steatohepatitis Hemochromatosis Alpha-1-antitrypsin deficiency Wilson’s disease Cryptogenic |
CHOLESTATIC DISEASES |
Primary biliary cirrhosis Primary sclerosing cholangitis |
Physical Examination
The physical examination is invaluable in establishing a diagnosis of cirrhosis. The liver may be enlarged in early stages or shrunken and firm in more advanced cirrhosis. Abdominal ascites with a fluid wave might be present.
There may be evidence of temporal muscle wasting in a decompensated cirrhotic patient. Jaundice and scleral icterus are usually detected at total bilirubin levels above 3 to 4 mg/dL. Spider angiomas—visible small arterioles—are common, particularly on the upper arms and chest.
Several findings are noted on examination of the hand. Palmar erythema is characterized by redness of the ball of the palm with the thenar and hypothenar eminences. Dupuytren’s contracture may be a nonspecific finding but is often seen in alcoholic liver disease; it involves the fourth and fifth fingers because of thickening of the palmar fascia. White nails and clubbing are often present. Asterixis (flapping tremor) may also be noted in decompensated patients with hepatic encephalopathy.
Gynecomastia, testicular atrophy, and pectoral alopecia are also commonly present. Xanthelasma, xanthomas, and calcinosis can be seen in patients with biliary cirrhosis. Xanthelasmas usually occur below the inner canthal fold of the eye and the eyelid. Xanthomas are most commonly found in the creases of the hands, arms, and legs. Calcinoses typically occur at pressure points such as the elbow and the ulnar surface of the forearm. Ascites, peripheral edema, splenomegaly, umbilical hernia, and caput medusae are seen in patients with advanced cirrhosis.
Disease Course
Patients with cirrhosis may live productive lives, but their disease may cause complications and death. Complications of cirrhosis include portal hypertension, often associated with the development of esophageal varices, hepatic encephalopathy, ascites, and spontaneous bacterial peritonitis. Furthermore, cirrhosis can lead to the development of hepatocellular carcinoma. Once a cirrhotic patient experiences a complication of portal hypertension with evidence of decreased hepatic synthetic function, or develops a hepatocellular tumor, the overall prognosis is very poor, and the patient should be evaluated for liver transplantation.
DIAGNOSTIC STUDIES
The evaluation, diagnosis, and treatment of patients with cirrhosis are expensive endeavors. Duplicate workups, such as performing a liver and spleen nuclear scan in a patient scheduled for a liver biopsy, add little to the diagnosis and should be minimized. However, much of the cost is incurred during evaluation and symptomatic treatment of various complications of chronic liver disease, and optimal therapy without unnecessary costs can be obtained only with accurate diagnosis and evaluation.
Laboratory Tests
Routine laboratory tests play a crucial role in recognizing chronic liver disease and subsequently delineating the etiology, particularly in healthy, asymptomatic persons. Rather than a single specific test, the combination of several tests assessing different aspects of hepatic physiology, measured over a period of time, can lead to the diagnosis.
Serum aminotransferase levels are a sensitive indicator of liver cell injury and hepatocellular necrosis. Alanine aminotransferase (ALT; or serum glutamic puruvic transaminase [SGPT]) and aspartate aminotransferase (AST; or serum glutamic oxaloacetic transaminase [SGOT]) are two such enzymes commonly measured in the routine assessment of liver dysfunction. ALT is thought to be more sensitive and specific for liver injury because it is present in highest concentration there, whereas AST is found in the liver, cardiac, and skeletal muscles; the kidneys; the brain; and elsewhere. Aminotransferase levels are usually elevated in all liver disorders. However, in cirrhosis, the degree of elevation is less than that in acute hepatitis and rarely rises above eight times the upper limit of normal except during flare-ups of chronic viral and autoimmune hepatitis. The AST:ALT ratio is of little diagnostic value except in the recognition of alcoholic liver disease, in which the AST: ALT ratio is often >2. It should be noted that the AST:ALT ratio can also be >2 in the presence of cirrhosis from any etiology.
Enzymes that detect cholestasis include alkaline phosphatase and gamma-glutamyl transpeptidase (GGTP). Alkaline phosphatase refers to a group of enzymes that catalyze the hydrolysis of organic phosphate esters at an alkaline pH and are mainly found in the bile canalicular surface of the hepatocytes, biliary epithelium, and bone. Hepatobiliary alkaline phosphatase elevations may be differentiated from other sources of alkaline phosphatase elevations either by measuring isoenzymes or by evaluating the serum activity of another “hepatic” enzyme, such as GGTP. Elevation of serum GGTP is found predominantly in hepatobiliary disease. About three quarters of patients with cholestatic liver disease have alkaline phosphatase values at least three times the upper limit of normal, with a minimal rise in the aminotransferases. However, these elevations do not distinguish between the intrahepatic and extrahepatic bile duct abnormalities.
The serum bilirubin level depends on a balance between the rate of production and removal from the liver. Unconjugated (indirect) hyperbilirubinemia results from overproduction (e.g., hemolysis) or impaired hepatic uptake or conjugation, as in Gilbert’s syndrome, which is a benign hereditary condition of mildly increased levels of serum unconjugated bilirubin. Conjugated (direct) hyperbilirubinemia results from decreased hepatic excretion or leakage of the conjugated bilirubin from diffuse liver injury or damaged bile ducts. Detection of bilirubin on a routine urinalysis indicates the presence of hepatobiliary disease because the unconjugated bilirubin is not excreted by the kidney.
The biosynthetic capacity of the liver is assessed by serum albumin and prothrombin time. Albumin is synthesized exclusively by the liver, and hypoalbuminemia is common in cirrhosis. A serum albumin level below 3 g/dL usually reflects severe liver damage. The liver is the most important site of synthesis for most blood coagulation proteins, and various components of the clotting cascade may be abnormal in cirrhosis. The prothrombin time is a most useful test in predicting the severity of hepatocellular damage. On a complete blood count, thrombocytopenia or leukopenia may be found (from hypersplenism secondary to portal hypertension), and microcytic anemia (from chronic gastrointestinal blood loss) or macrocytic anemia (e.g., alcoholic liver disease) is commonly present.
Imaging
Noninvasive radiologic imaging studies such as abdominal ultrasound with Doppler, computed tomography scanning, or magnetic resonance imaging can be suggestive of cirrhosis if there is caudate lobe hypertrophy or the liver appears morphologically nodular, especially amid radiographic findings of portal hypertension such as splenomegaly and ascites. In most cases, abdominal ultrasound is sufficient, unless the patient’s body habitus precludes an accurate study. If findings of cirrhosis appear incidentally on abdominal imaging, the laboratory tests mentioned earlier should be collected and the patient referred to a gastroenterologist for further evaluation.
Liver Biopsy
Although not a routine study, a liver biopsy is sometimes necessary to diagnose cirrhosis and confirm the etiology. The biopsy, often done via a percutaneous approach in an outpatient setting, should be done only after clotting factors are assessed and a complete blood count, including platelet count, is done. If ascites or severe coagulopathy and/or thrombocytopenia are present, a transjugular approach is preferred. This method has the added benefit of being able to measure estimated portal pressure. The results of a biopsy are not always conclusive, and further testing may have to be done.
Specific Findings
Detection of hepatitis B surface antigen in cirrhotic patients typically establishes the diagnosis of hepatitis B cirrhosis, whereas HCV infection is diagnosed by testing for anti-HCV antibody. If a test for anti-HCV by second-generation enzyme linked immunosorbent assay (ELISA) is positive, HCV RNA by polymerase chain reaction should be performed to confirm active HCV infection (as opposed to cleared), especially if antiviral therapy is being considered.
Autoimmune hepatitis is characteristically associated with hyperglobulinemia and circulating autoantibodies such as anti-nuclear and anti–smooth muscle antibodies. Often, one clue to its diagnosis is the coexistence of other diseases with immune or autoimmune features, such as thyroiditis (Krawitt, 2008). The diagnosis of primary biliary cirrhosis is made by a combination of positive antimitochondrial antibodies and increased immunoglobulin M on immune protein electrophoresis, in addition to characteristic histological findings on liver biopsy (Lindor et al., 2009). Primary sclerosing cholangitis is diagnosed when endoscopic retrograde cholangiopancreatography demonstrates the characteristic beaded bile duct appearance.
Hemochromatosis is an autosomal recessive metabolic disorder in which there is increased iron absorption over many years. Elevated serum ferritin levels and an increased percentage of transferrin saturation are typical biochemical findings. However, the best method of confirming the diagnosis is to measure quantitative hepatic iron content through liver biopsy. Alpha-1-antitrypsin deficiency is an inherited condition in which early-onset emphysema and a variable spectrum of liver disease can be found. About 1% of adult patients with cirrhosis are homozygous deficient. An adult with diagnosis of cryptogenic cirrhosis should be evaluated for this disease, and serum alpha-1-antitrypsin level should be measured and Pi typing carried out.
Another hereditary condition, Wilson’s disease, is an autosomal recessive disorder resulting in abnormalities in copper metabolism. Deficiency of the plasma copper protein ceruloplasmin, because of its impaired synthesis, is seen in more than 95% of these homozygote patients.
TREATMENT OPTIONS, EXPECTED OUTCOMES, AND COMPREHENSIVE MANAGEMENT