Urinary Flashcards
What are the top 10 diseases of the kidney?
(Know these or die)
Chronic Renal Disease
Ethylene Glycol Toxicity
Oak Toxicity
Leptospirosis
NSAIDs
Pyelonephritis
Infarcts
Progressive Familial Renal Nephropathy
Glomerulonephritis
Renal Azotemia
A 5 year old male cat is brought in for an exam because the owner notices him going to the litter box frequently. He also hasn’t been eating and seems lethargic for the past couple days. On exam, the urinary bladder is turgid. Xrays are performed. What is your diagnosis?
Bilateral hydronephrosis due to urethral urolith obstruction.
What is the likelihood that this congenital disorder will cause azotemia?
Unlikely. Bottom of your list for azotemia unless severe and bilateral.
These lesions are seen on the tongue of a cat with a history of renal disease. What directly caused these lesions?
Vasculitis and subsequent ischemia
What is the underlying lesion that causes hemorrhages and ischemic necrosis in animals with renal failure?
VASCULITIS
What complications are associated with this lesion in animals with renal failure?
Hemorrhage and ischemia
*This is severe vasculitis
A 10 year old dog is presented for necropsy with a history of bloody vomit and feces, PU/PD, lethargy, and anorexia. The dog has a BCS of 1/5 and is significantly dehydrated. The kidneys are nodular, small, and pale. Examination of the GI tract reveals hemorrhagic gastritis and colitis. What is the likely cause of the GI lesions?
Vasculitis secondary to renal failure.
A 9 year old Miniature Schnauzer presents for lethargy and anorexia. The owner also states that he’s been drinking more water and peeing a lot. The dog is thin and mm are pale. PCV is 28% and MCV is normal. What is causing anemia in this patient?
Renal failure.
*Mild to moderate, non-regenerative anemia. Kidneys aren’t producing erythropoietin anymore.
In a cow with severe hydrothorax and ascites, what are the mechanisms of renal disease responsible?
Vasculitis
Hypoproteinemia
This dog has kidney failure. What gland do you expect to be hypertrophied and how did the renal disease contribute to the abnormality seen here?
Parathyroid gland will be enlarged.
Kidney disease results in decreased synthesis of Vit D, and increased serum levels of P. Both of these things will decrease serum Ca++ levels. The PT gland will respond by mobilizing Ca++ from the bones, resulting in osteoclastic osteolysis and fibrous osteodystrophy (Rubber Jaw)
What are the 2 diseases of the kidney that contribute to edema by decreasing colloidal osmotic pressure?
Glomerulonephritis
Amyloidosis
*Moderate to severe! Albumin loss! (Won’t really notice with mild disease)
A dog with renal disease presents with generalized edema and petechiae of the mm. What is the mechanism of edema in this patient?
Vasculitis
*petechiae is the clue!
How is this lesion formed in renal failure patients?
Hyperphosphatemia due to decreased renal excretion leads to mineralization of soft tissues.
Mineralization of the vessels in a patient with renal failure. How can this be predicted and prevented?
Predict with labs: Ca x P level = .70 (risk for mineralization)
Prevent by lowering serum phosphorus levels (Phos-bind)
In what species is renal hypoplasia mainly seen?
Swine
Necropsy on a 4 month old dog with history of PU/PD and hypercalcemia reveals small, nodular, end-stage kidneys. Histopathology shows underdeveloped, or “embryonic” interstitium, tubules, and glomeruli. What is your diagnosis?
Progressive Familial Renal Dysplasia
Kidney of a cow with obstruction of the ureter. What is your diagnosis?
Hydronephrosis
This kidney lesion was found unilaterally in a dog. Would you expect to have seen azotemia in this patient?
No. Azotemia occurs when hydronephrosis is bilateral.
Why might you see azotemia in a patient with an acquired renal cyst?
Fibrous tissue that is obstructing the tubule and causing the cyst can be severe enough to cause azotemia, however, the cyst itself won’t cause azotemia.
PM exam of a Persian cat reveals kidneys with numerous cysts in the cortex and medulla, giving them a “honeycomb” appearance. What is your diagnosis for renal disease in this cat?
Congenital Polycystic Kidney disease
*Also inherited in Cairn and Bull terriers, Collies, Nubian goats, pigs and lambs
How does glomerulonephritis begin?
Ab-Ag complex deposition in the mesangium
What are 2 kidney disorders that could be causing the abdominal effusion seen in this patient?
Glomerulonephritis
Amyloidosis
What are some causes for the pathology in this kidney?
Idiopathic (most common)
Immune complex deposition:
Pyometra
Abscesses
Ehrlichia
HW Dz
FeLV
EIA
*This is glomerulonephritis
Gross pathology and histology on a dog who died with a history of renal disease. Grossly, the kidney looks end-stage. Histologically there is mineralization and fibrosis. What likely caused renal failure in this dog?
Glomerulonephritis
TEM image of an inflammed and thickened glomerular basement membrane. Why does the thicker membrane allow protein to leak through into the urine?
Immune complexes deposited are positively charged, which results in loss of negative charge of the glomerulus. Since the glomerulus is no longer negatively charged, proteins that are negatively charged aren’t repelled, and are allowed to pass through.
In addition to Congo Red stain, polarized light birefringence can be use to detect ______ in the glomerulus.
Amyloid
What type of amyloidosis is caused by deposition of amyloid AL, derived from Ig light chains produced by abnormal plasma cells?
Primary amyloidosis
What is the most common form of this disease in domestic animals, caused by chronic antigenic stimulation (inflammation, neoplasia, infection)?
Secondary (Reactive) Amyloidosis
Shar-peis and Abyssinians are known for what kidney disease?
Familial Renal Amyloidosis
*MEDULLARY amyloid deposition, fibrosis, papillary necrosis
Amyloidosis results in production of fibrinogen (positive acute phase protein), and renal loss of antithrombin, leading to what complication?
Thrombosis of pulmonary arteries and renal veins
Pathology found on PM exam of a dog. What are the renal differentials?
Amyloidosis
Glomerulonephritis
A 9 year old dog presents for PU/PD and generally ADR. The dog is thin with a distended abdomen. Labwork indicates hypoalbuminemia, azotemia, and increased cholesterol. A urine sample is dilute and has 3+ protein. No signs of hematuria or inflammation are seen. What is highly suspected in this patient?
Glomerular disease
*proteinuria with no hemorrhage or inflammation
*decreased serum protein (albumin)
A 9 year old dog presents for PU/PD and generally ADR. The dog is thin with a distended abdomen. Labwork indicates hypoalbuminemia, azotemia, and increased cholesterol. A urine sample is dilute and has 3+ protein. No signs of hematuria or inflammation are seen.
What tests can you use to confirm or refute glomerular injury in this case?
Urine protein/creatinine ratio
Biopsy
A 9 year old dog presents for PU/PD and generally ADR. The dog is thin with a distended abdomen. Labwork indicates hypoalbuminemia, azotemia, and increased cholesterol. A urine sample is dilute and has 3+ protein. No signs of hematuria or inflammation are seen.
Urine protein/creatinine ratio result is 10. What disease does this indicate?
Glomerulonephritis
A 9 year old dog presents for PU/PD and generally ADR. The dog is thin with a distended abdomen. Labwork indicates hypoalbuminemia, azotemia, and increased cholesterol. A urine sample is dilute and has 3+ protein. No signs of hematuria or inflammation are seen.
Urine protein/creatinine ratio is 20. What does this indicate?
Amyloidosis
A 3 year old Labrador presents for sudden illness. Labs indicate renal disease and a urine sample is very dilute, with hyaline and granular casts in the sediment. No bacteria is seen. What is a common cause of this disorder in dogs?
Ethylene Glycol toxicosis
*Nephrosis
Linear bands of necrotic tubules on a kidney biopsy from a dog with a history of a persistent bacterial infection. What is causing the lesions in this patient?
Antibiotics - Aminoglycosides
*Aminoglycosides accumulate in and damage renal tubular cells, causing nephrosis.
Nephrotoxins pigweed, Easter Lillies, grapes, and oakbuds are known to cause what type of renal injury?
Nephrosis (renal tubular necrosis)
You are called to examine a horse who fell ill after a long ride. Relevant blood results are as follows:
CK: 1,100,000 (145-380)
AST: 45,300 (220-600)
Urine was brown, despite ammonium sulfate test.
What pathology will this condition cause in the kidney?
Nephrosis
*Exertional rhabdomyolysis produces myoglobinuria due to massive muscle injury. Myoglobinuria is considered a toxin to the renal tubules and causes necrosis.
*Also seen in wild animals with capture myopathy
Analysis of serum in a sick patient produces a color change. You find calcium oxalate monohydrate crystals in the urine, and blood osmol and anion gaps are increased. What is the treatment of choice?
Fomepizole
*This is EG toxicosis. The 4 tests for early diagnosis are the KIT, crystalluria, osmol gap, and anion gap.
Chronic healed phase of nephrosis. What do the blue areas indicate?
Fibrosis
*loss of function! PU/PD!
Kidney with green/gray streaks, from a horse with a history of azotemia. What is the diagnosis?
Chronic Interstitial Nephritis
Histology from a 14 year old cat. Why was this cat showing renal signs?
Chronic Interstitial Nephritis. One glomerulus with a few tubules. Normal kidney tissue has been replaced by fibrous tissue and lymphocytic inflammation.
What are the 2 differentials for the white nodules in this bovine kidney?
CIN: White Spotted Kidney Dz
Lymphoma
*Histo or other gross lesions to differentiate
Necropsy on a foal reveals abscesses on the kidneys, and supperative inflammation in the eyes, liver, and joints. How did the foal likely get this disease?
Failure of Passive Transfer
*Neonatal septicemia in foals, calves, goats, pigs
Kidney from a dog in South America shows a white band and foci in the cortex. Another dog from the same family was treated with penicillin for acute illness and lived. What is the cause of acute interstitial nephritis in these patients?
Leptospirosis
*Diagnose clinically with serology and dark field microscopy of the urine
Interstitial nephritis in a cat with a history of increased serum globulin. On a blood film, protein stippling was seen in the background, and TNCC were mild to moderate. What is the etiology of the kidney disease in this cat?
Feline Infectious Peritonitis
What 2 viruses can cause marked lesions like this in the kidney of a cat?
Feline coronavirus (FIP)
Feline leukemia virus (Lymphoma)
*or spontaneous lymphoma
Is the infarcts in this kidney chronic or acute? Mild or severe?
Acute and severe
*Although the lesions are white, there is no scarring, meaning the lesions are still considered acute.
What is the likely pathogenesis of the subcapsular hemorrhage seen in this kidney?
Trauma
What are the 2 main general causes of this lesion?
Thrombocytopenia
Vasculitis
Kidney from one of multiple dead 1 week old puppies in a litter. Grossly, there is ecchymotic hemorrhage, giving the kidney a “turkey egg” appearance. Histologically there is necrosis. How can the owner prevent this in future litters?
Raise the ambient temperature
*Canine herpesvirus 1. Abortions and neonatal illness/death. Turkey egg kidney is diagnostic.
Renal cortical necrosis in a dog with a history of petechiae of the mm, increased aPTT, and increased FDPs. Histology shows fibrin thrombi in the glomeruli. What is the etiology and pathogenesis?
DIC
Hypercoagulable state leads to disseminated thrombi. Thrombi in kidney lead to ischemic cortical necrosis. Treat DIC before it gets to this point!
What is the most common portal of entry for the pathology seen in this kidney?
Ascending infection from the urethra/bladder
*This is pyelonephritis. Note supperative inflammation and irregular outline of renal pelvis.
*Other portal of entry is hematogenous (septicemia)
Marked supperative pyelonephritis in a cow, which has destroyed the renal pelvis. Ascending tracks of infection/inflammation in the cortex have caused what pathology in this kidney?
Interstitial nephritis
Kidney of a horse with a history of lameness. Grossly there is renal papillary necrosis. What is the likely pathogenesis?
Vasoconstriction and ischemic necrosis caused by administration of NSAIDS (phenylbutazone).
*Can also be caused by increased pressure (pyelonephritis, nephroliths, amyloidosis)
What is the cause of nephrosclerosis in this patient?
Staghorn calculi. Chronic!
White streaks outside the arcuate vessels in the kidney of a dog. Alternating tubules stain black with Sudan. What is the significance of these lesions?
No significance. Dogs and cats normally have lipid in the cortex.
*If white streaks appear on the inside of the arcuate vessels (in the medulla), and feel bumpy, Dx would be mineralization. This will also be visible on ultrasound.
PM exam of a dog’s kidney shows white streaks as pictured, that feel bumpy on cut surface. What is the clinical significance?
Mineralization.
*Streaks are inside the arcuate vessels.
Histopathology on the kidney of a Basenji who presented for PU/PD. Tubules appear normal despite presence of glucose and protein in the urine. What is the diagnosis?
Fanconi Syndrome
*The defect of biochemical, not structural. Tubules are unable to absorb things.
What is the pathogenesis of the trauma to the bladder in this patient?
Uroliths
This is a male (presence of a prostate), so cystitis can be caused by prostatitis. Contributing factor to stone formation, especially in male cats, is reduced water intake.
Spinal section from a Dachshund with a history of cystitis. What caused urinary issues in this patient?
Bladder atony and pooling of urine in the bladder due to decreased innervation caused by IVDD.
Bladder of a sheep who ingested Sorghum plants. What is the mechanism of cystitis in this patient?
Neurogenic. Reduced innervation to the bladder.
Bladder of a horse from the east coast who became ill and presented with oral lesions after ingesting Alfalfa hay. What is the likely cause of hemorrhagic cystitis in this animal?
Blister Beetle toxicity
You arrive at a farm to examine a steer with a distended abdomen. You take a sample of the abdominal fluid, and determining that it is urine, you admit the steer for surgery. Where is the bladder most likely to be ruptured in this animal?
Dorsal aspect
Bladder from a cat who was euthanized for urinary issues. What features of the bladder indicate that this problem had been going on for a number of days?
Hemorrhage and necrosis
*Will eventually lead to rupture
These stones were removed from the bladder of a 6 year old MN German Shepherd. What dietry recommendations can you give the owner of this dog?
Find a food with less corn gluten and soy bean hulls.
*These ingredients are high in silicates, which leads to the formation of silicate stones
You remove these stones from the bladder of a Persian cat with hypercalciuria and hyperoxaluria. What dietary change can the owner make to help prevent formation of these stones in the future?
Decrease protein intake to raise the pH of the urine. Calcium oxalate stones are found in acidic urine.
A 2 year old M English Bulldog presents for a second opinion on recurrent urolithiasis. Urine sediment has numerous ammonium urate crystals, confirming the diagnosis. What is the treatment protocol to manage this genetic predisposition?
Decrease protein intake to increase urine pH (ammonium urate stones like acidic urine), and supplement sodium bicarbonate.
Increase water consumption to dilute the urine (USG 1.020 or less)
Allopurinol (xanthine oxidase inhibiitor)
Stones found in the kidney of a dog who died with liver failure. How are the 2 related?
Liver failure increases ammonium concentration in the blood, leading to formation of these ammonium urate stones.
Renal biopsy taken from the kidney of a cat with azotemia, dilute urine, hypocalcemia, hyperphosphatemia, and nonregenerative anemia. What is your diagnosis?
Lymphoma
*Lymphocytic infiltration of most of the kidney is causing clinical signs in this patient.
Necropsy on a cat with white renal lesions. There is no inflammation in the abdominal cavity, and you find a mass in the diaphragm. Lymph nodes are enlarged. Is this FIP or LSA?
LSA (lymphoma)
Which of the following is the renal adenocarcinoma?
On the left. The tumor is invasive and is causing necrosis. The tumor on the right is an adenoma.
PM on a dog with a history of hematuria reveals a flaccid, sessile bladder with papillary type nodules. What is your diagnosis?
Transitional Cell Carcinoma
Bladder biopsy on a dog with hematuria. What is your diagnosis?
Transitional Cell Carcinoma
What dat?
Squamous cell carcinoma
You are having a hard time differentiating SCC from granulation tissue on a horse and decide to take an aspirate. What is the diagnosis based on the cytology?
SCC.
Squame tends to ulcerate so it’s not uncommon to see neutrophils. Granulation tissue will have macrophages or eosinophils.
