Liver Lab # 1

Miscellaneous liver lesions

Case F22342-04. 20 year old, male, castrated, domestic longhair cat.

Describe the changes: The liver contains multiple (>100), irregular red areas, measuring 1-4mm

in diameter. These areas were found throughout the capsular surface of the liver and extending

into the adjacent parenchyma.

What is this called? Telangiectasia

It is a dilation of sinusoids often seen in older cats (and occasionally cattle)

Case X16974-13. Mink. Alive this morning and died this afternoon.

Describe the lesion: The left lateral lobe of the liver is markedly enlarged, dark red, with a thin

layer of fibrin overlying the capsular surface and has undergone 360 degree torsion about its

base.

Morphologic diagnosis: Hepatic lobe torsion.

Case F21378-08. Adult, female, spayed domestic long hair cat. And Case: F9328-07. Female,

spayed, 8 year old, domestic short hair cat.

Describe the changes: The liver is swollen, pale and friable.

What is your morphologic diagnosis? Diffuse, severe hepatic lipidosis

What would help you in your diagnosis if you performed a necropsy at your clinic? The

liver would likely float in water or formalin.

Circulatory Disturbances

Case B20141. 4 year old dairy cow that went off feed recently. Increased heart rate, brisket and

submandibular edema. (see also B19670-97 and B2500-95)

Describe the changes: The liver is enlarged with rounded edges. On cross section, the liver has

a generalized, prominent tan reticular pattern (“nutmeg liver”).

Give a morphologic diagnosis: Severe, subacute hepatic congestion

What is the significance of this lesion: It is consistent with right-sided heart failure. This cow

had traumatic reticuloperitonitis due to the presence of a wire that penetrated the reticulum and

caused pericarditis. The presence of right-sided heart failure also explains the brisket and

submandibular edema.

Case P3093-09. 3 ½ months old, male pig.

Describe the changes: Several (approximately 3-6) discrete, white, tan foci are noted at the

edges of several liver lobes.

Give a morphologic diagnosis: Liver: multifocal, acute, severe, hepatic infarcts.

Case B17990-13. 2 ½ months old poor doing calf. And Case B18446-11. In vitro fertilization

calf, 1 month old. And Case B6714-94 Three week old calf.

S. Martinson

Describe the changes: The umbilical stalk, arteries and vein are distended with thick yellow

exudates. There is a large abscess in the liver at the end of the umbilicus. Multifocal smaller

abscesses (1-3cm in diameter) are present throughout the liver.

Give a morphologic diagnosis: Severe, chronic, multifocal to coalescing hepatic abscessation

and severe, suppurative omphalophlebitis/arteritis

How did the lesion come about? Ascending infection from the umbilicus.

Case B9594-11. Three year old, Holstein cow and Case B856-04 5 year old Holsten cow.

Describe the changes: A large, cylindric piece of organized fibrinopurulent exudate (20cm long

and 3-7cm in diameter) originating in the liver and extending cranially into the vena cava is

present. Numerous 2-5cm in diameter abscesses are scattered in the liver.

What is your morphologic diagnosis?

1. Focal, chronic, suppurative phlebitis (Vena caval thrombosis and abscessation)

2. Multifocal-coalescing, chronic-active, moderate-severe hepatic abscessation

What other organs should you examine?

- The heart for endocarditis as emboli would shower off of this thrombus

- The lungs for pulmonary abscesses and thromboembolism

- The rumen for ongoing rumenitis

Cirrhosis and Nodular Hyperplasia

Case F-13965-91. Male, castrated, 13 year old domestic short hair cat. Longstanding elevation in

liver enzymes, weight loss and anorexia.

Describe the changes: The liver is pale, firm and diffusely nodular. The nodules vary from 0.3-

2cm and extend throughout the parenchyma. Opaque strands of fibrous tissue separate the

nodules.

Morphologic diagnosis: Hepatic fibrosis with nodular regeneration

This is a cirrhotic liver which is associated with old age, previous exposure to toxins (e.g.

aflatoxin), infectious agents or disease (e.g. hepatic lipidosis). Often the cause is undetermined.

Case C18888-04. 10 year old, female mixed breed dog.

Describe the changes: The liver is small, with an irregular capsular surface and multiple 1-8mm

round nodules replacing majority of hepatic parenchyma.

Morphologic diagnosis: Hepatic cirrhosis with micro and macronodular hyperplasia (hepatic

cirrhosis or end-stage liver).

Case C1195-99. 11 year old, mixed breed dog.

This is a picture of acute leptospirosis in a dog

Describe the lesion: The liver is mottled with variably sized, coalescing pale areas and multiple,

raised, firm nodules.

Give a morphologic diagnosis: Multifocal, necrotizing hepatitis with nodular hyperplasia.

This animal was thought to have had Leptospirosis. Histology and immunohistochemistry were

required for diagnosis.

Case F271-84. 12 year old, female, domestic short hair cat.

Describe the lesion: the liver is distorted due to innumerable, variably sized pale nodules

throughout the parenchyma and raised above the surface.

What is the morphologic diagnosis? This is nodular hyperplasia, but appropriate differentials

would be chronic hepatic fibrosis and regeneration (cirrhosis) as well as neoplasia.

LESSON: Nodular hyperplasia, cirrhosis and neoplasms can look similar. Liver biopsy

(and thus histology) is required for diagnosis.

This is an image of a feline liver with micronodular cirrhosis

Another great resource for studying is the Tufts gross image collection

(http://ocw.tufts.edu/Course/72/Coursehome)

Congenital Lesions

Case B18345-97. Six month old, calf.

Describe the lesion: The liver is small, with an irregular surface. The parenchyma is dissected

and effaced by dense white fibrous connective tissue.

Morphologic diagnosis: Severe, chronic, diffuse hepatic fibrosis

This is a described congenital lesion of calves.

Case B1456-04. 1 week old calf.

Describe the lesion: A large cystic mass filled with fluid and partially compartmentalized mass

originates from the left caudal edge of the liver.

Morphologic diagnosis: Congenital heptatic cyst.

Case C8339-05. 2 month old German Shepherd puppy with a history of fever and convulsions.

Describe the changes: There is a large vessel connecting the portal vein to the caudal vena cava.

What is your morphologic diagnosis? Extrahepatic portosystemic shunt (portal vein to caudal

vena cava).

Affected animals are often stunted and exhibit signs of hepatic encephalopathy.