Liver biopsy is an important diagnostic tool in assessing the nature and severity of liver disease. Liver biopsy provides information concerning
 
1. the cause of the liver damage
2. the degree of ongoing liver injury
3. 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 - Risks
 
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:
 
1. Bleeding requiring
a. transfusion in less than one per thousand biopsies
b. surgery in less than per thousand biopsies
2. Penetration of other organs such as lung, kidney, gallbladder,
intestine
3. 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
 
Liver Biopsy - Procedure
 
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
 
Absolute Contraindications
Uncooperative patient
History of unexplained bleeding
Tendency to bleed*
Prothrombin time > 3-5 sec more than control
Platelet count <50,000/mm3
Prolonged bleeding time (> 10 minutes)
Use of NSAID within previous 7-10 days†
Blood for Transfusion unavailable
Suspected hemangioma or other vascular tumor
Inability to identify an appropriate site for biopsy by percussion
or ultrasonography
Suspected echinococcal cysts in the liver
 
Relative Contraindications
Morbid obesity
Ascites
Hemophilia
Infection in the right pleural cavity or below the right
hemidiaphragm
(* Although these criteria are considered absolute
contra-indications by most hepatologists, they can be corrected by
transfusions of platelets or fresh-frozen plasma and are therefore
not truly absolute.)
(SOURCE: Bravo AA, Sheth SG, Chopra S. Current Concepts: Liver
Biopsy. N Engl J Medicine 2001; 344: 498, Table 2.)
  
†  Use of aspirin within 7-10 days is an absolute contraindication
to liver biopsy. Use of other NSAIDS within the previous 3 days is
generally an absolute contraindication.  
 
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/palpationor 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 - Histopathology
 
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
 
You can view these tables at:
http://hepcvets.com/cirrhosis/score/fibinf.html
 
References
 
Bravo AA, Sheth SG, Chopra S. Current Concepts: Liver Biopsy. N
Engl J Medicine 2001; 344(7):495-500.
Ibid., 498 (table 2).
 
Batts KP, Ludwig J. Chronic hepatitis. An update on terminology and
reporting. Am J Surg Pathol 1995;19(12): 1409-17.
 
Ludwig J, Batts KP, Moyer TP, Poterucha JJ. Advances in liver
biopsy diagnosis. Mayo Clin Proc 1994 Jul;69(7):677-8.