Watch out for Hepatitis C
HEPATITIS CHepatitis C is the most important cause of chronic liver disease in the world. Latest estimates from the CDC indicate that nearly 4 million people in the USA are infected. There are 8-10,000 deaths yearly from this disease, and it is suggested that the number of patients who will develop cirrhosis and complications, as well as liver cancer, will escalate in the next decade to astronomical proportions. Initially, this RNA viral infection was thought to occur only following blood product transfusion. We now know since 1993 and the development of widespread blood bank screening policies, that the majority of infections today are the result of intravenous drug use. The majority of patients seen today are 30-50 years of age, who are noted by their primary care physician to have abnormal liver function tests. This often leads to referral to a gastroenterologist or hepatologist for more detailed work-up. Close to 75% of patients who are exposed to the Hepatitis C virus will develop chronic hepatitis, and the natural history reveals that close to 25% of these chronics will develop cirrhosis, usually over the span of 15-20 years. Hepatitis C and resulting cirrhosis are the most common cause or indication for liver transplant in the USA today.
EPIDEMIOLOGY
Of the five well-defined viruses (A, B, C, D, E) that can cause liver disease, Hepatitis B and C are the most ominous. Both can cause chronic hepatitis (abnormal liver tests for more than 6 months). Hepatitis B is clearly falling in prevalence in the last 10 years as a result of blood bank screening and vaccination. Hepatitis C is transmitted via blood to blood contact. Intravenous drug use, nasal cocaine, body piercing, tattoos, acupuncture, ear piercing, or sharing razors or toothbrushes of infected victims are means of transmission. If you have tried drugs, even once, you are at risk. Sexual contact, especially with those that may be promiscuous, is another less common route of infection. If you believe you may have had contact, or may be at risk, seek screening blood work with your primary care physician.
CLINICAL PRESENTATION
For many patients, chronic viral hepatitis is clinically silent, especially early before established chronic hepatitis or cirrhosis develops. Fatigue that worsens during the day is common. Others may experience right upper abdominal pain, nausea, skin rash, joint pain, loss of appetite, malaise, low grade fever, mood alterations, weight fluctuations, or jaundice (yellowing of the skin and eyes). Some experience itching, sleep habit changes, and marked irritability.
DIAGNOSIS
The physical exam done by your physician is usually unremarkable. Chronic hepatitis is diagnosed via laboratory tests that sort out all the causes of chronic hepatitis, and then can confirm Hepatitis C and begin the staging process. Liver enzymes may or may not be elevated in this disease, and the degree of elevation does not always coincide with the degree of liver involvement. Antibody to Hepatitis C will not appear in the blood until nearly 8 weeks after infection. We now have third generation lab tests that confirm infection and utilize polymerase chain reaction (PCR) to quantify the amount of virus present in the blood. There are a number of conditions that can lead to a “false-positive” Hepatitis C antibody test, so it is important that your physician do the proper confirmatory tests. Hepatitis C RNA can be detected in the blood as early as 2 weeks after exposure, and the PCR can detect as few as 10 copies per milliliter of blood. Once the diagnosis is established, it may be necessary to have an ultrasound of the liver to view its internal character and size. A liver biopsy is often next, and this should be a rather simple out-patient procedure done by the hepatologist or radiologist. The biopsy is taken utilizing a local anesthetic, and some IV sedation. The biopsy helps us determine whether cirrhosis is present, and allows the physician to properly stage your disease prior to therapy.
TREATMENT
The goal of treatment is viral eradication. Patients between the age of 18-65 should be considered candidates for therapy with “combination” regimens of alpha-Interferon and Ribavirin, a nucleoside analogue. Interferon is an anti-viral that needs to be injected three times a week, and Ribavirin is a pill that is taken daily. Therapy ranges from 6-12 months depending on the so-called genotype of the virus. The drugs are fraught with many potential side-effects, including fever, nausea, malaise, joint pain, fatigue. mood swings, and periods of manic or depression. The flu-like symptoms usually lessen or disappear after 3-4 weeks of therapy. Most patients can still work and carry on their lives, while some need to be disabled to complete the regimen. Ribavirin can cause a serious anemia (low red cell count), and female patients cannot consider pregnancy during treatment. The cost of this therapy is $10-15,000 a year, yet covered by most insurance carriers. The response rate for a year of therapy in patients with genotype 1 is in the range of 35-40%. For those with non-genotype 1, the rates elevate to 60-80%.
THERAPIES ON THE HORIZON
All of us look forward to the release of pegylated Interferon, which is due by January, 2001. This form of Interferon is structured so as to be injected just once a week, avoiding some of the peaks and valleys with Rebetron that we now use. The response rates also look more encouraging, approaching 55% in genotype 1 (nearly 75% of Americans are type 1). A variety of other agents are being worked on, including Thymosin, Amantadine, protease, and helicase inhibitors, ribozymes, other interferons, and the interleukins to name a few. We forecast that in the next 2-3 years, there will be a group of three to four agents to attack this virus, similar to our success with HIV. Please stay tuned to this web page for more information.
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