Hepatitis C

Risk: Exposure to hepatitis C-infected blood is the primary risk factor, which may occur during shared use of intravenous needles or razors, treatment with poorly sterilized medical instruments, contact with open cuts or wounds, sexual contact, hemodialysis, and tattooing or body piercing. Individuals who work in healthcare professions (including paramedics) are at higher risk because they are more likely to come into contact with infected blood.

Alcoholics, individuals with cirrhosis, those over age 40, and those who have been infected with the virus for 20 to 40 years are more susceptible to developing HCV-related liver cancer. Men are at a higher risk than women of developing this cancer. HIV-positive individuals are more likely to die from end-stage liver disease if infected with HCV.

Incidence and Prevalence: There are an estimated 4 million individuals, or 1.8% of the US population, with antibodies to hepatitis C, indicating current or previous infection with the virus. Hepatitis C causes approximately 10,000 to 12,000 deaths in the US each year; approximately half the cases of primary liver cancer in developed nations are caused by hepatitis C (Hoofnagle).

History: Although early symptoms of the disease are often absent, individuals may report muscle and joint aches, fatigue, headaches, weight loss, and weakness. Other prominent symptoms may include loss of appetite, nausea, and mild right-upper-quadrant discomfort or tenderness. In more advanced stages of the disease, an individual might develop dark urine, itching, abdominal pain, and bloating. Because laboratory tests are not always definitive, the individual's clinical and social histories are important for diagnosis in the early stages of the disease. The virus progresses more rapidly in individuals with HIV.

Physical exam: The exam may show enlargement of the liver (Hepatomegaly) and spleen (Splenomegaly). Progressive liver disease may be indicated by visible branching capillaries on the skin (spider nevi), redness of the palms of the hand (Palmar Erythema), and a liver that is firm on examination. There may also be jaundice, muscle wasting, ascites, ankle swelling, and skin abrasions (excoriations) from scratching.

Tests: Although anti-HCV is detected by enzyme immunoassay (EIA), false-positive results occur occasionally. A sensitive assay such as polymerase chain reaction (PCR) or transcription mediated amplification (TMA) is the best method of confirming this diagnosis. The presence of HCV RNA indicates active infection. Antibody is present in almost all patients by 1 month after onset of acute illness. Individuals who have compromised immune systems may test negative for anti-HCV, despite having the virus, because they may not produce enough antibodies for detection with EIA, thus the necessity of another means of diagnosis. Immunoblot assays can also be used to confirm anti-HCV reactivity.

Progressive liver disease may be indicated if abnormal values in other blood tests are found, such as serum albumin or the platelet count. In this case, a small piece of the liver may be removed for microscopic examination (liver biopsy). Some specialists recommend that liver biopsies be performed in all cases in which hepatitis C has been identified to rule out liver damage.