Some context for yesterday’s post about Fibrosure, a new test marketed as an alternative to liver biopsy:
Liver biopsies are used to assess the amount of damage to the liver, measuring fibrosis and inflammation. Biopsies can provide valuable information on disease progression and whether hepatitis C treatment is needed - information that other tests like hepatitis C viral load and liver enzyme tests can't tell you. Biopsies can also identify or rule out other potential causes of liver damage.
Biopsies are usually performed by hepatologists or gastroenterologists, though interventional radiologists are increasingly utilized by many hospitals and clinics. A long, thin needle is inserted in the liver to collect a tissue sample, which is then analyzed in a lab by a pathologist.
Most doctors use a local anesthetic at the site of biopsy to numb the pain. The person undergoing a biopsy needs to remain awake during the procedure, though partial sedatives are sometimes used.
About a third of people experience some pain following the biopsy, which generally goes away within a day. Pain medication is sometimes prescribed.
There’s a small risk of complications from biopsies, due to the risk of internal bleeding. Complications occur in up to 3% of biopsies, and there is a slight risk of death – less than 1 in 10,000. For these reasons, people receiving biopsies are generally kept in the hospital for about four hours after the procedure for observation. The risk of complications is lower when a biopsy is performed by an experienced clinician, and ultrasound can be used to select the proper location for inserting the biopsy needle.
Biopsies are considered the gold standard in assessing liver damage. However, biopsies aren’t perfect, and involve a degree of subjectivity. The accuracy of liver biopsies ranges from 80-90%. Sampling error and difficulties in interpreting the tissue sample have been documented. Some reports indicate that larger tissue samples reduce the likelihood of sampling error.
Most doctors will want to perform a biopsy before making a decision about hepatitis C treatment. If the biopsy results show little or no fibrosis, many doctors and patients would defer treatment, since there is no immediate risk of serious liver disease. In this case, some doctors would recommend a repeat biopsy in 3-5 years to monitor fibrosis progression (perhaps sooner, in 2-3 years, for people co-infected with HIV).
If you’re considering getting a biopsy, talk to your doctor about the procedure. Ask how many biopsies they’ve performed (the more the better), and consider asking what they would give you for pain, if necessary. Talk to other people who’ve had liver biopsies – many will tell you that it’s not as painful as it sounds, and it’s over very quickly. Consider bringing a friend with you when you get a biopsy, and be prepared to stay for a few hours afterwards. Make sure you have a way of getting home safely – if you drive, have a friend pick you up.
References and Further Reading
Fact sheets and general information
From the Veteran's Administration's new hepatitis C website:
Liver Biopsy questions and answers (geared towards patients)
Liver Biopsy overview (geared towards clinicians)
Review articles from the 2002 Hepatology supplement on Management of Hepatitis C, covering data presented at the NIH hepatitis C consensus conference
Other journal articles of interest
Current concepts: Liver biopsy (Bravo, Sheth and Chopra; New England Journal of Medicine, February 2001; abstract)
Diagnosing fibrosis in hepatitis C: is the pendulum swinging from biopsy to blood tests? (Afdhal commentary; Hepatology, May 2003; abstract)
Sampling variability of liver fibrosis in chronic hepatitis C (Bedossa, Dargère and Paradis; Hepatology, December 2003; abstract)