Lab 4: Chronic Cell Injury, Adaptations

Question 1

This rabbit was cachectic and had a distended abdomen and some diarrhea. At necropsy the liver had multiple white spots.

1. What is happening here?
2. What is happening here and at 4?
3. ?

5.?

Answer 1

1. Cystic bile ducts.
2. Bile duct epithelial hyperplasia
3. Normal bile duct
4. Coccidia intracellular parasites (Eimeria stiedae)

Question 2

This rabbit was cachectic and had a distended abdomen and some diarrhea. At necropsy the liver had multiple white spots. There is an agent present, Eimeria stiedae, an intracellular protozoan parasite.

1. How the intracellular protozoan parasite be related to the lesion?
2. Do the lesions seen on the slide correlate with the lesions observed during necropsy?

Answer 2

1. The irritation and inflammation that occurs in response to the parasite leads to proliferation of the epithelium, perhaps through elaboration of growth factors.
   
   • Lysis of cells due to intracellular growth of the intracellular coccidium is further stimulus for a reparative effort.
   • Remember, one cause of hyperplasia is chronic irritation.
2. Yes, the multiple white spots correlated to the enlarged bile ducts

Question 3

• What tissue is the first picture?

1. What is the space pointing to at 1?
2. what type of cells are these

Answer 3

• Normal prostate
  1. Normal prostatic alveoli
  2. Cuboidal to columnar epithelial cells

Question 4

The second 2 pictures are from a dog with a history of constipation

3. What is seen at 3?
4. ?

Answer 4

3- Prostatic hyperplasia

• Each alveolus is larger than in the normal because there are more cells in the lumens of these alveoli.
• The cells are virtually the same as normal, but there are more of them
• There are papillary projections of excess cells into the centers which here appear as disconnected rafts of cells

4- Some cells are taller: hypertrophy in addition to hyperplasia

Question 5

what is this an image of?

Answer 5

Prostatic hyperplasia

Question 6

This dog had an abdominal testicle containing a Sertoli cell tumor. (this is not an image of the testicle)

• What tissue is this from?

Answer 6

prostate

Question 7

This dog had an abdominal testicle containing a Sertoli cell tumor. (this is not an image of the testicle)

1. What is seen at 1 (the space)?
2. ?
3. ?
4. ?

Answer 7

1. Prostatic alveoli that should have columnar secretory cells
2. Alveolar lining is stratified squamous
3. keratin squames
4. mineralized squames (hardened karatin)

Question 8

This dog had an abdominal testicle containing a Sertoli cell tumor. (this is not an image of the testicle)

1. What is the change (diagnosis)?
2. What is the likely cause?

Answer 8

1. Prostatic squamous metaplasia
2. estrogen toxicity
   • It turns out that neoplastic Sertoli cells (found in the tumor in the cryptorchid testis) often produce estrogen.
   • This is an example of a paraneoplastic syndrome (see neoplasia chapter).
   • Besides the prostatic lesion, these animals often have gynecomastia and become attractive to other male dogs.
   • BOOBS

Question 9

How may the prostatic squamous metaplasia be treated?

Answer 9

• Removal of the Sertoli cell tumor is the best bet since estrogen levels would fall to normal and the metaplasia would reverse.
• Theoretically you could treat with testosterone but you would still have the tumor to deal with.

Question 11

The tissue was from a dog with vaginal discharge, polyuria and polydipsia, and fever.

• What tissue is this?

Answer 11

Canine, uterus

Question 12

Canine, uterus. The tissue was from a dog with vaginal discharge, polyuria and polydipsia, and fever

1. What is seen here?
2. ?
3. ?
4. ?

Answer 12

1. Hyperplastic endometrium
2. Mucus on surface
3. Endometrial cysts
4. Neutrophils

Question 13

Canine, uterus. The tissue was from a dog with vaginal discharge, polyuria and polydipsia, and fever

• What is seen at 5?
• 6?
• 7?
• 8?

Answer 13

5- Hemorrhage and

6- Neutrophils in lumen

7- Endometrial cyst with neutrophils (purulent endometritis

8- Myometrium

Question 14

Histomorphologic Diagnoses?

This section of enlarged uterus is characterized by: 1) cyst formation and hyperplasia of endometrial glands, 2) accumulation of mucopurulent exudate in lumens of cystic glands, and 3) accumulation of plasma cells in stromal tissues around endometrial cysts.

Answer 14

1. Severe diffuse cystic en­dometrial hyperplasia.
2. Acute diffuse mucopurulent endometritis
3. Chronic diffuse plasmacytic and eosinophilic periglandular endometritis.

Question 15

What is the relationship, if any, between the hyperplastic and the inflammatory change?

Answer 15

• The hyperplasia is likely due to repeated estrous cycles without breeding resulting in prolonged metestrus and progesterone stimulation, which causes gland hyperplasia.
• While inflammation can cause hyperplasia, as you saw in the rabbit above, in this case the inflammation is usually superimposed on the cystic hyperplasia due to ascending bacterial infection.
• Bacteria find a cozy niche in the hyperplastic uterus for growth, which causes the inflammation.
• In addition, a progesterone stimulated uterus is more prone to infection compared to one under estrogen influence.

Question 16

Canine, uterus. The tissue was from a dog with vaginal discharge, polyuria and polydipsia, and fever.

1. ?
2. ?
3. ?

Answer 16

1. Hyperplastic endometrium
2. Endometrial cysts
3. Neutrophils

Question 17

Tissue from an 14 year old feline with renal failure

• Describe the lesions.

Answer 17

• The musculature of the forelimb exhibits decreased mass and definition (atrophy).
• This is most pronounced in the supraspinatus and infraspinatus muscles, manifested in the prominence of scapular spine.

Question 18

Tissue from an 14 year old feline with renal failure.

• What type of cellular adaptation does this represent and what might be a possible pathogenesis, given the history?

Answer 18

• This is an example of atrophy of skeletal muscle.
• Weight loss and muscle wasting in older felines has been associated with an increase in Maintenance Energy Requirements, and decreased efficiency of digestion resulting in a loss of lean mass as well as adipose tissue.
• This can fall under the categories of an aging change, as well as a decrease in nutritive supply.
• Additionally, renal disease is frequently associated with a decrease in appetite and cachexia.

Question 19

Tissue from a 2 year old doe that was culled due to failure to thrive.

• Describe the lesions:

Answer 19

• The kidney on the right is diffusely small, and on cut section, the cortex appears thin.
• The kidney on the left is diffusely enlarged.

Question 20

Tissue from a 2 year old doe that was culled due to failure to thrive.

1. What type of cellular adaptation is this?
2. How does this happen?

Answer 20

1. Congenital hypoplasia of the right kidney with compensatory hypertrophy of the left kidney.
2. As the animal develops, the poorly-functioning, hypoplastic kidney imparts an increased fluid load on the normal kidney.
   
   • To compensate, the normally functioning kidney (the left in this case) enlarges due to an increase in the length and diameter of its existing nephrons (super nephrons), not due to an increase in the number of nephrons.

Question 21

Tissue from a 4 year old intact female Collie with a 1-2 week history of anorexia. She presented on emergency with a painful abdomen and hematochezia.

• 1. What organ is this?
• 3. What organ is this?
• 4. What organ is this?

Answer 21

1- Duodenum

3- Pancreas

4- stomach

Question 22

Tissue from a 4 year old intact female Collie with a 1-2 week history of anorexia. She presented on emergency with a painful abdomen and hematochezia.

• Describe the lesion seen at 2

Answer 22

The peri-pancreatic fat is multifocally discolored (grey) with widely disseminated petechiation.

Question 23

Tissue from a 4 year old intact female Collie with a 1-2 week history of anorexia. She presented on emergency with a painful abdomen and hematochezia.

1. What process has occurred in this tissue at 2?
2. Why did this happen?

Answer 23

1. Enzymatic necrosis of fat, refers to the destruction of fat in the abdominal cavity and usually surrounding the pancreas
2. due to the release of activated pancreatic enzymes including lipases that escape from a damaged pancreas. This could be secondary to a mass or an infection (pancreatitis).

Question 24

What is this showing?

Answer 24

foci of enzymatic necrosis of fat on the surface of the pancreas and in the mesenteric fat.

Question 25

Tissue from a 17-yr old Quarter Horse gelding found dead on corn stover pasture following a sudden drop in temperatures.

1. Describe the lesion.

Answer 25

• The epicardial fat is markedly diminished, exposing the coronary vessels in the interventricular (paraconal) groove and coronary sulcus.
• The minimal adipose remaining is translucent and gelatinous with a slight pinkish cast.

Question 26

1. What process has occurred in this tissue?
2. Why?
3. Estimate the duration of this disease state (i.e. acute, subacute, chronic).

Answer 26

1. This is an example of serous atrophy of fat
2. due to caloric insufficiency, in this likely due to malnutrition.
3. Chronic

Question 27

What other lesions would you expect to find in other organs?

Answer 27

• Serous atrophy of fat around the kidneys and lining the pelvic cavities.
• There may also be other signs of decreased caloric availability, such as muscle wasting (atrophy).

Question 28

List a few different ways in which this disease state (weight loss) may have occurred.

Answer 28

1. Starvation can be due to a decrease in food intake either due to availability, inability to reach the food provided, or pain upon eating (such as a lesion in the oral cavity).
2. It could also be due to malabsorption or utilization- the animal is consuming enough food, perhaps more than enough, but those calories are simply “passing through”.
   
   • The causes of malabsorption can vary- enzyme deficiency, neoplasia, parasitism, or infectious disease.

Question 29

Tissue from an 8 year-old, intact male German Shepherd with a 3 month history of stranguria.

1. What organ is this?
2. ?

Answer 29

1. bladder
2. prostate

Question 30

Tissue from an 8 year-old, intact male German Shepherd with a 3 month history of stranguria.

• Describe the lesions. (may not be able to tell some from picture)

Answer 30

• Prostate: The gland is diffusely and symmetrically enlarged, approximately 6cm x 2cm x 6cm in size, and on cut surface it is pale tan to pink.
• Urinary blader: The muscular wall of the bladder is approximately 5mm thick (thicker than normal).

Question 31

Tissue from an 8 year-old, intact male German Shepherd with a 3 month history of stranguria.

1. Name the process occurring in this organ and relate it to the clinical history
2. Why does this happen?
3. Is this reversible?

Answer 31

1. Hyperplasia (prostate) and
   
   • Hypertrophy (bladder).
2. This is an example of benign prostatic hyperplasia.
   
   • The prostate is enlarged due to pathologic hyperplasia of the acinar epithelial cells and hyperplasia of the fibromuscular stroma.
   • The cause is thought to be related to relative or absolute increase in testosterone and frequently develops in aged, intact male dogs.
   • The urethra passes through the prostate, and is compressed by the hyperplastic gland resulting in straining to urinate and hypertrophy of the muscular wall of the bladder.
3. Yes reversible. This lesion will resolve following removal of the inciting hormone (castration).

Question 32

Tissue from a neonatal goat that died shortly after birth

• Describe the lesion.

Answer 32

• Diffusely, the lobes of the thyroid glands are uniformly enlarged approximately 5-6 times normal (approximately 6 x 4 cm).
• The glands are uniformly tan and solid on cut surface.

Question 33

Tissue from a neonatal goat that died shortly after birth.

1. Name the process occurring in this tissue
2. How does this happen?

Answer 33

1. Thyroid hyperplasia
2. This is an example of goiter (non-neoplastic thyroid enlargement).
   • Congenital goiter (this case) can result from either dietary iodine (necessary for appropriate thyroid hormone production) deficiency in the dam or a genetic defect in the biosynthetic pathway of thyroglobulin in the fetus.
   • The lobes of the thyroid are enlarged due to diffuse hyperplasia of follicular cells.

Question 34

Tissue from a 7 year old female Chihuahua mix that had a markedly domed head since birth.

1. Describe the lesions:
2. What is the name of this lesion?
3. What is the duration of this lesion?

Answer 34

1. The lateral hemispheres of the brain are enlarged. The surrounding cortex is thin, with flaccid walls.
2. Hydrocephalus (internal)
3. Chronic

Question 35

Tissue from a 7 year old female Chihuahua mix that had a markedly domed head since birth.

1. At what point in this animal’s life did it likely develop?
2. What type of adaptive process is occurring?

Answer 35

1. While it is possible to acquire hydrocephaly later in life as a consequence of CSF outflow obstruction (by a tumor, for example), the doming of this dog’s head suggests that the bones of the skull expanded to accommodate the increased intracranial volume.
   
   • This means that the lesion is likely congenital or perinatal (occurred before fontanelle closure, which is usually complete by 4 months).
2. ​adaptive process- Pressure atrophy.