Biopsy Specimens

For needle core and wedge biopsy specimens see Gastrointestinal Specimens - General Comments (page 7).

Note that viral hepatitis is a category III pathogen - it should be submitted to the laboratory with an attached hazard of infection sticker and handled appropriately after 24-48 hours of thorough formalin fixation.

Routine histochemical stains that should be provided to help assess the degree of hepatic parenchymal loss, reticulin collapse/elaboration and fibrous distortion/replacement respectively, are PAS (± diastase), silver reticulin and Masson Trichrome. Haemochromatosis is diagnosed and graded by Perl's Prussian Blue or the dry-weight iron concentration is determined biochemically. Other stains are: rhodanine/Shikata's orcein for copper in Wilson's disease, primary biliary cirrhosis or chronic cholestatic disorders; PAS + diastase (globules in alpha-1 antitrypsin deficiency) and Congo Red (amyloid).

Needle cores may have an adherent fragment of skin if obtained percutaneously. They can also fragment in diseased liver with cirrhosis or tumour. Fatty liver is pale, haemochromatosis rusty. One aspect of a wedge biopsy is covered by peritonealised capsule and its cut margin is often frayed by diathermy. This margin should be painted and the wedge then cut into multiple vertical serial slices perpendicular to it.

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