Test 3: lab 5 urinary Flashcards
Tissues from a dog with chronic kidney disease.
Describe the lesions in the kidney and the other tissue.
The kidneys are small with an irregular, pitted cortical surface and have tan areas of fibrosis. There is hydronephrosis. The pleura covering the intercostal muscles has a deposit of slightly raised, roughened, white material that covers and obscures the underlying muscle. Similar material is present along the endocardial surface of the left atrium. The ventral surface of the tongue has dark, linear ulcers bilaterally.
Do you think that this kidney disease is acute or chronic?
What 4 main renal functions can this kidney no longer perform?
This is an example of chronic renal disease. In comparison, acute kidney injury will result in slightly enlarged, swollen, pale and edematous kidneys or gross changes may be difficult to see at all.
- Excrete metabolic waste
- Maintain water, acid-base, and electrolyte homeostasis
- Conserve nutrient substrates (protein, glucose)
- Regulate endocrine functions
What is the condition that describes both the renal and extrarenal lesions in this animal?
What other tissues or organs (besides the one shown here) can be affected by this condition?
Uremia or Uremic syndrome
- Brain – uremic or metabolic encephalopathy
- Lung – uremic pneumonitis
- Stomach – uremic gastritis
Tissues from a cat with chronic kidney disease. A normal feline kidney (from a different cat) has been added for reference.
Describe the affected kidney and the parathyroid glands:
The kidney is severely diffusely small with an irregularly pitted surface and firm, pale tan areas of fibrosis (consistent with chronic kidney disease). The parathyroid glands are severe diffusely enlarged bilaterally.
Give a pathogenesis that describes the relationship between the renal changes and the parathyroid gland changes:
Renal insufficiency → decreased GFR → decreased phosphorous excretion → increased PO4 in blood → altered Ca and PO4 ratio with hydroxyapatite crystal deposition → low serum Ca → low Ca detected by parathyroid glands → increased PTH production → parathyroid gland hyperplasia due to secondary renal hyperparathyroidism
Provide a morphologic diagnosis (or diagnoses).
How can you tell which lesion is acute vs. chronic?
Acute and chronic renal Infarcts
The acute infarcts are tan and red, wedge-shaped aresa in the renal cortex, corresponding to areas of acute necrosis and hemorrhage.
The chronic infarcts are the depressed areas in the cortices, corresponding to tissue loss and replacement with fibrosis (scar) that contracts over time, pulling the cortical surface inward.
Provide a morphologic diagnosis (or diagnoses).
How can you tell which lesion is acute vs. chronic?
Acute and chronic renal Infarcts
The acute infarcts are tan and red, wedge-shaped aresa in the renal cortex, corresponding to areas of acute necrosis and hemorrhage.
The chronic infarcts are the depressed areas in the cortices, corresponding to tissue loss and replacement with fibrosis (scar) that contracts over time, pulling the cortical surface inward.
What is a possible pathogenesis of these lesions?
Renal infarcts can be a sequela of vegetative valvular endocarditis. Specifically, vegetative lesions on the AORTIC or MITRAL (left AV) valves lead to renal infarcts. The renal artery branches from the abdominal aorta and a large percentage of the cardiac output is received by the kidney.
What part of the kidney is primarily affected?
Provide a morphologic diagnosis.
The innermost renal medulla, called the renal papilla (or renal crest in some species including the horse, dog, sheep).
Severe acute renal papillary (renal crest) necrosis
kidney
What is the most common cause of this lesion?
What is the pathogenesis of this lesion?
NSAID administration. NSAIDs that are commonly administered to horses include phenylbutazone (bute) and flunixin meglumine (banamine).
NSAIDs inhibit COX enzymes > decreased prostaglandin production (PGE2) by medullary interstitial cells > loss of vasodilatory action > ischemia of the inner medulla > necrosis of renal papilla (the cortex is spared)
Name 2 possible sequelae of NSAID administration leading to renal papillary necorosis
Pyelonephritis (necrotic debris can act as a nidus for infection)
- Nephrolithiasis (necrotic debris can also act as a nidus for calculus formation)
- Hydronephrosis (chronic necrosis and loss of medullary parenchyma can result in dilation of the renal pelvis)
What are some abnormalities that you would expect to find on a biochemistry panel from an animal with AKI?
- Azotemia (increased BUN and creatinine)
- Electrolyte alterations
- Metabolic acidosis
sheep kidney
Describe the sheep kidney and give a morphologic diagnosis and an etiology.
The sheep kidney is dark red-brown. Severe diffuse acute
renal tubular necrosis, copper toxicity.
What are the TWO main causes of Acute Tubular Injury?
- Ischemia
- Nephrotoxins
The tube contains a urine sample from one of these animals. What scientific terms correctly describe this urine?
- Pigmenturia – pigmented (colored) urine
- Hemaglobinuria – hemoglobin in the urine
- Myoglobinuria – myoglobin in the urine
- Hematuria – blood in the urine
Match the animal, cause of AKI, and the histologic lesion.
Dog - Antifreeze – Calcium oxalate crystals (nephrotoxin)
- Sheep - Copper – Hemoglobin casts (nephrotoxin and ischemia)
- Horse - Rhabdomyolysis – myoglobin casts (nephrotoxin)
stones in kidney
These specimens are all examples of what condition?
Urolithiasis.
The goats presented to the hospital as “blocked goats” with complete obstruction of the urethra by stones (obstructive urolithiasis). Clinical signs include straining to urinate with no detectable urine production, vocalization, abdominal distension (if bladder rupture), and abnormal mentation. This is a very common presentation in castrated male goats or sheep (called wethers). The goat bladder also has hemorrhage of the bladder wall due to either stones in the bladder or pressure necrosis from buildup of urine because of the urethral obstruction.
Stones in the kidneys of the otter and horse are called nephroliths. The horse and otter may have had different clinical presentations, such as abdominal pain, chronic weight loss, biochemistry changes (increased BUN, creatinine), etc.
Provide a list of differential diagnoses for the lesion in the urinary bladder.
- Urothelial cell carcinoma (previously called transitional cell carcinoma)
- Rhabdomyosarcoma (young dogs)
- Leiomyosarcoma (rare)
One kidney looks different than the other. What is the term for the change in the kidney that is BIGGER?
The pelvis of one kidney is markedly dilated, and this kidney is larger than the one on the contralateral side. The term for dilation or enlargement of the renal pelvis is hydronephrosis.
What is the pathogenesis of the lesion in this kidney?
Hydronephrosis in this case is due to obstruction of the ureter by the neoplasm. You may also have noticed that the ureter is dilated (hydroureter). The neoplastic tissue is preventing normal flow of urine from the renal pelvis into the ureter and then urinary bladder. This “back up” of fluid results in distension of the ureter and renal pelvis. Over time, the compression of the renal medulla by the distended renal pelvis results in atrophy of the renal tissue.
dog testis- irregularly lobulated firm, pale tan to white tissue.
Morphologic diagnosis:
Function of the cell of origin:
Sertoli cell tumor
Sertoli cells provide support and nutrients to the germ cells to help facilitate spermatogenesis. They also help maintain the blood-testis barrier.
3rd most common in dogs (rare in other animals)
estrogen and inhibin
dog testis with soft yellow mass
Morphologic diagnosis:
Prognosis:
Interstitial (Leydig) cell tumor
benign
Name the two conditions affecting this uterus:
Pyometra and cystic endometrial hyperplasia
Diagnosis
Mammary gland tumor. Further characterization requires histopathology. Mammary tumors can contain a variety of tissue types, ranging from tubules of epithelial cells to regions of cartilage or bone.
horse ovary
Diagnosis:
What is the biological behavior of this neoplasm?
Granulosa cell tumor
benign
What hormones might granulosa cell tumor produce, and what associated changes might you notice?
Granulosa cell tumors can produce inhibin, anti-Mullerian hormone (AMH), estrogens, or androgens. Depending on which hormones are elevated and by how much, they may cause atrophy of the contralateral ovary, alterations in the estrus cycle, or stallion-like behavior.
Diagnosis:
Where else in the reproductive tract can this neoplasm occur?
Vaginal leiomyoma
Leiomyomas can occur within the uterus, cervix, or vagina in the female reproductive tract.
