Chapter 57: Viral Hepatitis

KEY CONCEPTS

• Hepatitis A virus (HAV) is transmitted via the fecal–oral route, most often from ingestion of contaminated food or water, or through contact with an infected person.

• HAV causes an acute, self-limiting illness and does not lead to chronic infection. There are three stages of infection: incubation, acute hepatitis, and convalescence. Rarely, the infection progresses to liver failure.

• HAV is vaccine preventable. There is no pharmacological treatment specifically for HAV as treatment consists of supportive care.

• Hepatitis B virus (HBV) causes both acute and chronic infection. Chronic infections are responsible for high rates of liver disease, liver cancer, and death.

• Vaccination can prevent HBV and is the most effective strategy in preventing complications of HBV infections. Prevention of HBV infections focuses on immunization of all children and at-risk adults.

• The purpose of anti-HBV drug therapy is for viral suppression and immune control and to prevent progression of liver disease and the complications associated with HBV infections.

• Initial therapy of chronic HBV is with tenofovir or entecavir because these agents have a high barrier to resistance. Therapy is often long term.

• Patients undergoing immunosuppressive therapy or chemotherapy should be screened for HBV infections and may require HBV therapy to reduce the risks of reactivating their HBV and developing fulminant liver failure.

• The hepatitis C virus (HCV) is an insidious, blood-borne infection. Increased screening of all patients born between 1945 and 1965 was implemented to help identify the many people unaware of their infection.

• Hepatitis C infections can cause significant morbidity (including extrahepatic manifestations) and mortality. Patients with chronic hepatitis C are at risk for end-stage liver disease, cirrhosis, liver transplant, and death as a result of their infection.

• The goal of anti-hepatitis C virus (HCV) drug treatment is cure. Drug therapy with direct-acting antivirals (DAAs) is highly effective and well tolerated.

Patient Care Process for Hepatitis C

Collect

• Patient characteristics (eg, age, sex, weight, vital signs, etc.)

• Patient history (past medical, family, social) and medical record summary including surgical operations (site, date, procedure) and abdominal imaging findings

• Thorough medication history (include prescription, nonprescription medications, and other substances) and drug allergies and intolerances. Previous HCV therapy, if applicable.

• Laboratory results for chronic HCV infection including HCV genotype and viral load (RNA)

• Laboratory results for other viral infections impacting HCV treatment (HBV core antibody, HBV surface antigen, HBV surface antibody, HAV total or IgG antibody, HIV status)

Assess

• Determine severity of underlying liver disease based on laboratory tests, clinical calculators, imaging, and clinical history

• If the patient has cirrhosis, assess the level of liver dysfunction using the Child-Pugh Score to determine options for HCV therapy

• Estimate creatinine clearance to identify which HCV therapies may be used

• Review insurance ...