Lecture 4: Liver 1 Flashcards
(44 cards)
Portal hypertension can be prehepatic, intrahepatic or post-hepatic. Of these, one is more common than the other two. Which one?
Intrahepatic causes are most common (the other two are rare).
What are some of the clinical signs and gross lesions seen in a puppy
with a congenital portosystemic shunt?
- Stunting, relative to littermates; 2. Hepatic encephalopathy (manifesting as mental dullness); 3. Small liver size.
Which types of equids are prone to development of hepatic lipidosis?
Ponies, mini horses & donkeys
What is the characteristic histologic lesion of hepatic lipidosis?
Clear cytoplasmic vacuoles within hepatocytes.
What is the cause of the fibrous tags or plaques found on the diaphragmatic surface of the liver of horses?
unknown
What is the significance of tension lipidosis in cattle?
None; it’s incidental and insignificant.
Where, precisely, in the liver is amyloid deposited in cases of amyloidosis?
The spaces of Disse
What is the underlying cause of excessive glycogen accumulation in the liver?
Excessive glucocorticoids [either exogenous (iatrogenic) or endogenous (hyperadrenocorticism)]
What is hepatic telangiectasia? What does it look like grossly?
Randomly scattered areas of dilation of hepatic sinusoids by blood where hepatocytes have been lost. Grossly, it appears as dark red “dit-dots” and patches throughout hepatic parenchyma.
What histologic changes would you expect in the liver of an anemic animal?
Centrilobular hepatocyte degeneration and necrosis with dilation and congestion of centrilobular sinusoids by blood. [Note that “enhanced reticular pattern” is a gross, not a histologic change and is not an acceptable answer, sorry.]
In which phases or periods are cattle most susceptible to developing hepatic lipidosis, and why?
Fat cows in late gestation, immediately post partum or in peak lactation. Excessive mobilization of body fat stores to cope with demand overwhelms liver’s ability to process and export it –> accumulation.
What is the characteristic histologic lesion of hepatic lipidosis?
Clear cytoplasmic vacuoles within hepatocytes.
What is the underlying pathogenesis of hepatic lipidosis?
The rate of accumulation of triglycerides within hepatocytes exceeds the rate of their removal
What is the most common reason for chronic passive congestion in the liver?
Chronic right-sided heart failure (for a variety of reasons)
Excessive administration of glucocorticoids by veterinarians can cause what substance to accumulate in the liver? What is the term for this condition?
Glycogen. “Steroid hepatopathy”
What is tension lipidosis?
Areas of pallor in hepatic parenchyma where the liver is suspended by ligaments.
You are performing a necropsy on a bird euthanized for chronic foot infections and notice that the liver is swollen, pale, waxy and friable. What is the most likely cause of the liver lesion?
Hepatic amyloid accumulation (amyloidosis)
What is the characteristic signalment and scenario for a cat that develops hepatic lipidosis?
Obese cat –> stressed (disease, change of environment etc.) –> goes off food for several days –> idiopathic accumulation of lipids in hepatocytes.
What is the gross appearance of a liver with acute passive congestion (give 3 gross findings)?
- Slight hepatomegaly; 2. Enhanced reticular pattern / centrilobular congestion; 3. Oozes blood from cut surfaces
In what type of animal is the edge of the liver fimbriated or “frilly”?
Camelids (llamas etc.)
In which domestic species are fibrous tags or plaques often found on the diaphragmatic surface of the liver?
Horses
What is the most common reason for an INTRAhepatic congenital portosystemic shunt?
Intrahepatic congenital PSSs are generally due to failure of closure of the ductus venosus at birth. [The ductus venosus is a normal fetal vessel that conducts blood from the umbilical vein to the caudal vena cava.]
Describe the gross appearance of a liver affected by hepatic lipidosis.
Enlarged, friable, pale, greasy, may float in formalin
Explain the difference between the terms “nutmeg liver,” “enhanced lobular pattern” and “enhanced reticular pattern.”
“Enhanced lobular pattern” and “enhanced reticular pattern” mean the same thing and are interchangeable terms. Both refer to any repeating lesion within all hepatic lobules, including (for example) periportal inflammation or cancer, centrilobular necrosis, and midzonal glycogen accumulation (i.e., anything that causes a repeating dark-light pattern at the level of every hepatic lobule). “Nutmeg liver” is a form of enhanced lobular pattern reserved for the chronic passive congestion associated with chronic right sided heart failure.
