The risk of a liver biopsy is minimal. The primary risk is bleeding from the site of needle entry into the liver, although this occurs in less than 1% of patients. Other possible complications include the puncture of other organs, such as the kidney, lung or colon.
Biopsy, by mistake, of the gallbladder rather than the liver may be associated
with leakage of bile into the abdominal cavity, causing
peritonitis. Fortunately, the risk of death from liver biopsy is
extremely low, ranging from 0.1% to 0.01%.
A biopsy should not be done if: 1) you have taken aspirin in the last 5-7 days, 2) the hemoglobin is below 9-10 grams/dl, 3) the platelets are below 50,000-60,000, or 4) the prothrombin time INR is above 1.4. Those with bleeding disorders such as hemophilia which can be temporarily corrected with transfused clotting factors can be biopsied safely.