Liver Biopsy

Liver biopsy is an important diagnostic tool in assessing the nature and severity of liver disease. Liver biopsy provides information concerning

	the cause of the liver damage
	the degree of ongoing liver injury
	the extent of chronic liver damage

Liver biopsy provides the clinician with confirmation of the diagnosis of hepatitis C, as well as a determination of the amount of inflammation and fibrosis. In HCV infection, there is a poor correlation between symptoms or levels of alanine aminotransferase and histologic features of the liver. Thus, patients with HCV infection may have normal levels of liver enzymes and have significant fibrosis on biopsy. Conversely, patients may also have elevated serum ALT and trivial liver disease.(1)

Liver biopsy carries a small risk of complications. If performed correctly, most patients do not feel pain during the biopsy. Some of the risks include the following:

	Bleeding requiring transfusion in less than one per thousand biopsies surgery in less than per thousand biopsies
	Penetration of other organs such as lung, kidney, gallbladder, intestine
	Fatality in less than one per ten thousand biopsies

Because of the small risk of complications, liver biopsy should only be performed when the information will be useful for optimal patient care and only after written informed consent has been obtained. In hepatitis C, this would include

	prior to starting HCV treatment
	determination of extent of liver damage, particularly in patients with persistent, significant elevations in ALT

A liver biopsy can usually be safely performed as an outpatient procedure. A physician trained and experienced in the procedure should perform the liver biopsy. Prior to the procedure, patients should discontinue all anticoagulants (e.g., coumadin) for at least a week and should not take aspirin or other non-steroidal anti-inflammatory medicines for about a week (patients can take acetaminophen). Additional contraindications to percutaneous liver biopsy include the following:(2)

For the procedure:

	Patients must provide written informed consent
	Patients are placed flat in bed and the liver is localized in the right mid-axillary line
	Localization of the liver can be performed by percussion/palpation or by ultrasound
	Some physicians administer conscious sedation prior to the liver biopsy
	The skin over the biopsy site is cleaned with betadine or another suitable antiseptic, and lidocaine is injected locally to anesthetize the skin and the capsule of the liver
	Liver biopsy is performed by quickly inserting and then withdrawing a 15 to 18-gauge needle into the liver. A successful biopsy obtains a piece of liver tissue approximately the diameter of the lead in a pencil and 1 inch long

Post-Procedure:

	The patient lies on his/her right side for 1-2 hours and then on his/her back for 3-5 hours (total observation after liver biopsy is 4-6 hours)
	Blood pressure and heart rate are checked frequently during this time
	Patients are allowed to go home if they can follow instructions reliably and have easy access to a hospital should they develop bleeding or other complications
	Patients should remain off anti-coagulants, aspirin and NSAIDs for at least one week
	Patients should be advised to refrain from heavy lifting or strenuous exercise for one to two weeks following the procedure

Liver biopsy provides the best information available concerning the amount of hepatic fibrosis and the amount of ongoing inflammation and necrosis. Inflammation is characteristically predominantly located in the portal area and consists of a mixture of mononuclear cells and lymphocytes. In more severe cases, inflammation and necrosis of the lobular parenchyma is present. Fibrosis usually begins in the portal area in HCV and in the central vein in alcoholic liver disease. Bridging fibrosis refers to the presence of fibrosis that reaches from a portal area to another portal area. Cirrhosis consists of extensive bridging fibrosis in the presence of regeneration such that normal portal areas and normal central veins cannot be identified.

One grading system used for assessing inflammation and fibrosis is that of Batts and Ludwig.(3)

Other grading systems include Metavir and Histologic Activity Index (Knodell Score).

1. Bravo AA, Sheth SG, Chopra S. Current Concepts: Liver Biopsy. N Engl J Medicine 2001; 344(7):495-500.

2. Ibid., 498 (table 2).

3. Batts KP, Ludwig J. Chronic hepatitis. An update on terminology and reporting. Am J Surg Pathol 1995;19(12): 1409-17.

1. Ludwig J, Batts KP, Moyer TP, Poterucha JJ. Advances in liver biopsy diagnosis. Mayo Clin Proc 1994 Jul;69(7):677-8.