The silent dragon—hepatitis C - Home Study Program

AORN Journal, June, 2003 by Beverly Walker, Linda Howard

Other liver function tests. Bilirubin and albumin levels and prothrombin time (PT) also can be evaluated. Bilirubin is the major breakdown product of red blood cells. The liver removes it from the blood, chemically modifies it, and secretes it into the bile for excretion. In most chronic, acquired liver diseases, serum bilirubin concentration is normal until a significant amount of liver damage has occurred and cirrhosis is present. Albumin, a protein synthesized in the liver, is secreted into the bloodstream. Low levels indicate poor liver function, although concentration usually remains normal until a chronic condition progresses to cirrhosis. Low albumin levels are associated with conditions other than liver disease, such as malnutrition and renal disease. When liver function is severely impaired, the synthesis and secretion of clotting factors is reduced. Prothrombin time is prolonged, although in chronic disease levels remain normal until cirrhosis is present and severe tissue damage has occurred. The PT time also can be delayed in other conditions, such as vitamin K deficiency and nonliver disorders and by certain medications. (40)

A liver biopsy is performed to stage the liver disease activity or monitor response to treatment. On the basis of a histological evaluation of liver tissue, the disease is classified by severity of damage and amount of scar tissue present. This is the most reliable test for determining liver damage. (41)

TREATMENT AND SIDE EFFECTS

Currently approved medications for initial treatment of HCV are interferon and ribavirin. Interferons are proteins produced naturally by the body. Specific interferons act as immunomodulators that enhance the immune system's ability to identify and attack the virus. Experts do not understand the mechanisms behind its effectiveness fully, and response to the medication varies among individuals. A patient who presents with a histologically mild form of the disease, has low pretreatment viral load, and is younger at the time of onset of chronic infection has predictably higher chances of a favorable response. (42)

Medications. The standard initial course of treatment is alpha-interferon at a dose of three million international units (IUs) subcutaneously three times per week. The goal of treatment is suppression of the active disease to a degree that minimizes liver damage. Coupling the medication with a nucleoside analogue antiviral agent (eg, ribavirin) seems to be more effective than the standard regimen of interferon alone. On its own, ribavirin does not inhibit HCV, but when combined with interferon, consistently higher rates of sustained response are reported. (43) The combined agents, however, work for only 35% to 45% of the patient population, depending on viral genotype and other factors. (44) When the frequency of injections is increased to daily doses, remission rates have increased to 60%. (45)

Patients who initially respond to interferon and subsequently relapse after treatment cessation can be considered for an additional course of combination therapy or a change in type or dose of interferon. Three different interferons (ie, alpha-2a, alpha-2b consensus) have been approved for initial HCV treatment. The first course of treatment with alpha-2a and alpha-2b is three million IU per day subcutaneously three times per week for 12 months. For consensus interferon, the initial treatment regimen is 9 mg to 15 mg subcutaneously. (46) A response is considered to be sustained when the HCV RNA remains undetectable for six months or more after therapy stops. Table 4 is an algorithm for treatment that reflects current trends in initial therapy. (47) Table 5 shows a nursing care plan for a patient with HCV.