Liver Biopsy Remains Gold Standard

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Liver Biopsy Remains Gold Standard

“ACP: Liver Biopsy Not Foolproofâ€

By Peggy Peck, Senior Editor, MedPage Today

Reviewed by Jasmer, MD; Assistant Professor of Medicine,

University of California, San Francisco

April 10, 2006

MedPage Today Action Points

* Explain to patients who ask that despite any failings, the liver

biopsy remains the gold standard for assessing chronic liver disease.

Review

PHILADELPHIA, April 10 - Liver biopsy is considered a gold standard

for staging chronic liver disease, but this gold standard is

sometimes fool's gold, according to data reported here.

Because the biopsy relies on needle placement liver disease may be

missed, said K. Rajender Reddy, M.D., director of hepatology and

medical director of the liver transplantation program at the Hospital

of the University of Pennsylvania.

For example, Dr. Reddy said at the American College of Physicians

meeting, in one series cirrhosis was missed in up to 20% of biopsies

and the grade of inflammation or state of fibrosis was consistently

underscored.

He illustrated his point with a slide of a cross-sectional sample

from a cirrhotic liver on which he overlaid biopsy needle placement.

Needles placed in one location completely missed cirrhotic tissue,

while a needle placed just a few millimeters away detected advanced

cirrhosis.

As a result, " a patient may be told at one point that he or she has

mild disease, only to find out a year later that the liver is

cirrhotic, " he said.

The risk of error can be reduced, he told internists attending

a " Multiple Small Feedings of the Mind " hepatology update, by

attention to specimen size and number of specimens.

" Adequate specimens are at least 1.5 cm long, but accuracy is better

for specimens 2 cm long and the best results are obtained with

specimens that are at least 2.5 cm long, " he said. Likewise,

specimens should be at least 1 mm wide but 1.4 mm is better and 2.0

mm is the best.

Moreover, he said that at least six portal triads are needed but " 11

is better. "

Dr. Reddy acknowledged that because liver biopsy is an invasive

procedure both referring physicians and referred patients are often

reluctant to undergo biopsy.

But the alternative, which would be use of indirect markers, " is not

ready for prime time. "

However, Dr. Reddy offered some tips about interpretation of those

markers. The most common, he said, is the ratio of aspartate

aminotransferase (AST) to alanine aminotransferase (ALT) ratio. " When

AST is higher, it suggests cirrhosis, " he said.

Another non-invasive marker than may have some utility is

AST:platelet ratio index, which is calculated as follows:

AST:platelet ratio index = [(AST/ULN)/platelet count] X 100 where the

platelet count is expressed as cells/uL and ULN stands for upper

limit of normal. But this index has not been validated in clinical

trials.

There are a number of tests of which the best known are FibroTest and

ActiTest, both made by Oneida TheraDiagnostics Ltd. Both tests are

recommended for use in assessing liver status following diagnosis of

hepatitis C, but the tests are not intended as a substitute for liver

biopsy.

Primary source: American College of Physicians

Source reference:

Reddy, I L “Multiple Small Feedings of the Mind: Hepatology,

Infectious Diseases in the Office, Update on Treatment of ACS and

CHF†MSFM