Pathology of the liver and pancreas Flashcards
What are the 3 hepatic zones?
PERIPROTAL/CENTROACINAR - around portal triads MIDZONAL
CENTRILOBULAR/PERIACINAR - bordering the hepatic venules
How wide is a classic lobule?
2mm diamter
What is the origin of a PSS?
CONGENITAL - shunting into VC, azygous or renal vein. Usually a single communication between the vessels. ACQUIRED - shunts secondary to fibrosis in older animals, multiple thin-walled shunts (see image)
List some other congenital and develipmental disorders of the liver
-Congenital cysts -Displacements -Tension lipidosis -Capsular fibrosis -Telangiectasis
Where are congenital cysts found?
Biliary mainly in cats (also dogs and pigs), can be multiple
Example of a displacement
diaphragmatic hernia
What is tension lipidosis?
focal areas of subcapsular fatty change (may relate to local ischaemia)
What is capuslar fibrosis?
fibrous tags are common on the surface of the liver in older horses (due to migrating parasites or foci of non-spetic peritonitis)
What is tealngiectasis?
foci of sinusoidal dilatation (cats and cattle)
This image shows capsular fatty change and telangiectasis.
What type of a disorder is passive venous congestion?
a circulatory disorder
Presentation - passive venous congestion?
acute or chronic usually associated with right-sided heart failure
Gross pathology -passive venous congestion? 2
liver enlarge with rounder borders and oozes blood on cut surface, enhanced lobular pattern (nutmeg liver)
Microscopy - passive venous congestion? - 3
hepatic venules and sinusoids engorged; periacinar areas congested with atrophy of hepatocytes (red); periportal areas undergo fatty chage (pale colour)
List 4 disorders of pigmentation. Which one does this image show?
MELANIN - congenital (lambs and calves) HAEMOSIDERIN - chronic passive venous congestion) BILE - obstructive jaundice LIPOFUSCHIN or CEROID - ageing.
Image shows haemosiderin (blue strikes)
What are vacuolar hepatopathies?
A degenerative disease. Hydropic change is common, non-specific and reversible. Glycogen (glycogenosis) accumulation occurs in HAC. Multifocal to diffuse swelling and vacuolaton of hepatocytes. Enlarged pale liver in severe cases (steroid hepatopathy). See images
Causes of vacuolar hepatopathies - 3
Hypoxia, mild toxic damage and metabolic stress
4 broad causes of hepatic lipidosis (fatty liver)
Dietary, increased energy demand, disease, abnormal hepatocytes function that prevents FAs complexing with proteins to form low density lipoproteins.
Lysosomal storage disease - overview and diagnosis
-OVERVIEW: inherited deficiencies of lysosomal enzymes cause neurological disease. Macrophages containing stored material accumulate at multiple sites (liver, LNs, CNS). -DIAGNOSIS: liver biopsy or PME
What happens in amyloidosis?
Substance depositied under th enedothelium and basement membranes of a variety of tissues including the renal glomeruli, islets of langerhans in the pancreas and the liver.
Broad causes - amyloidosis - 3
Primary, secondary or endocrine related
Gross appearance - amyloidosis
liver pale, enlarged, and friable
Microscopic appearance - amyloidosis
Homogenoeous acidophilic material that shows green birefringence when stained with congo red
When can liver necrosis occur? 4
Following ishaemia, toxic damage, nutritional deficiencies, microbial infection
3 different patterns of necrosis = ? What is this image an example of ?
RANDOM - EHV-1 or salmonellosis ZONAL - ischeamie or toxic damage MASSIVE - hepatosis dietetica,
The image shows periportal necrosis.
4 patterns of liver fibrosis = ? What does the image show?
PERIACINAR - surrounds central vein, chronic passive congestion BILIARY - accompanying inflammation centred on the portal triads POST-NECROTIC SCARRING - following massive necrosis CIRRHOSIS - extensive fibrotic lesions, end stage liver, may be concurrent nodular regeneration.
The image shows biliary fibrosis.
Define cholangitis
Inflammation of the bile ducts, may be immune mediated (cats) or associated with infection (salmonellosis in calves)
Cholangiohepatitis - define
Inflammation of parenchyma and bile ducts
Define hepatitis
Inflammation of the liver parenchyma (often caused by infection)
Outline the progression of necrosis - 4
Acute hepatitis generally involves necrosis, succeeded by inflammation. If the animal survives then progression is: -complete resolution by regeneration -repair by fibrosis and scarring -encapsulation by abscessation -persistence by granulomatous disease
3 causes of viral hepatitis.
-ADENOVIRUS - canine infectious hepatitis (ICH) -HERPESVIRUS - EHV-1, IBR, feline viral rhinotracheitis/rhinopneumonitis, equine viral rhinopneumonitis Aujeszky’s disease -CORONAVIRUS - FIP Generally in young or unvaccinated animals
How is infectious canine hepatitis spread?
Long-term shedding in urine of canine adenovirus 1 (CAV-1) virus particles