Renal Labs Flashcards
Describe this lesion. History: tissue from a cat.
Kidneys: There are multifocal cystic structures ranging in size from 0.5-2 cm in diameter. They are present on the capsular surface and also extend into the parenchyma of the renal cortex and medulla. The surrounding parenchyma is compressed.
Give a morphological diagnosis.
Kidney: bilateral multifocal renal cysts (polycystic kidneys)
Describe this lesion. History: tissue from a young cat that was hit by a car.
One kidney measured 2 x 1.5 cm (small). The contralateral kidney measured 6 x 4 cm (large)
Give a morphological diagnosis.
Kidney: unilateral renal hypoplasia with contralateral compensatory hypertrophy
Describe this lesion. History: tissue from a young dog. The patient had a history of chronic urinary incontinence
the renal pelvis is markedly dilated with substantial loss and thinning of the renal cortex and medulla. The ureter is diffusely dilated
Give a morphological diagnosis.
Kidney: diffuse hydronephrosis and hydroureter
What is the likely pathogenesis for this lesion?
congenital abnormality of the ureter causing vesicoureteral reflux or a stricture causing an impedance to urine outflow causing back up of pressure leading to dilation of ureter and renal pelvis + atrophy of renal parenchyma
Describe this lesion. History: canine stillborn
Kidneys: The medullary parenchyma of the kidney is compressed and dilated. The cortex is compressed and thin. The ureter is dilated. The bladder is flaccid and largely distended.
Give a morphological diagnosis.
Kidney: hydronephrosis Ureter: hydroureter
What is the mechanism forming this lesion?
obstruction of the lower urinary tract causes increased pressure and dilation of the ureters and renal pelvis
What is the possible cause in this case?
congenital urethral abnormality
Describe this lesion. History: tissue from a 6 week old american bulldog puppy. The patient presented with a distended abdomen.
The right kidney had been replaced by a large, well-demarcated mass measuring approximately 12 x 11 x 10 cm. The cut surface of the mass was moderately firm, uniformly tan to cream-colored, and had a multilobular appearance. Normal underlying renal parenchyma was not evident.
Give a morphological diagnosis.
right kidney: diffuse unilateral multilobular renomegaly
List possible differential diagnoses.
nephroblastoma, renal cell carcinoma, transitional cell carcinoma, metastatic tumors, granulomatous/pyogranuloomatous nephritis
Describe this lesion. History: tissue from a dog. The patient had a history of stranguria, pollakiuria, and hematuria
There are multifocal irregularly shaped concave slightly pale areas on the renal cortical surface. On cut surface, the depressed area correspond to pale fibrotic connective tissue that penetrated through the cortex to the corticomedullary junction and focuses on an arcuate artery.
Give a morphological diagnosis.
Kidney: chronic, multifocal, renal infarcts
What is the likely cause of this lesion?
septicemia or endocarditis
Is this lesion chronic or acute and why?
chronic because there is fibrosis in this lesion whereas if it were acute there would be more swelling and hyperemia
Describe this lesion. History: The cow calved about 2.5 months ago prior to euthanasia. She was normal for the first couple weeks postpartum, but she quickly dropped off in milk production, was anorexic, depressed, and had lost a significant amount of weight. The cow was humanely euthanized due to worsening condition and failure to respond to treatment. The main necropsy finding was vegetative valvular endocarditis.
Kidney: There are large, multifocal, to coalescing well demarcated, wedge shaped to irregularly shaped areas of tannish discoloration (necrosis) bordered by a narrow zone of dark red (hemorrhage). On cut surface, these areas extending from the cortex to the corticomedullary junction. The pale areas are soft in comparison to the surrounding renal parenchyma. The abnormal areas range in size from 2 cm up to 8cm in diameter.
Give a morphological diagnosis.
Kidney: multifocal, acute/subacute, severe renal infarcts
Is this lesion chronic or acute and why?
acute - arterial infarcts are always pale and result in coagulative necrosis, if the lesion were chronic then it would be red to purple in color
What is the pathogenesis of this lesion?
Valve defect -> colonization of the valve leaflet after a period of bacteremia -> infiltration of the leaflet by inflammatory cells ->formation of vegetative masses on the leaflet edges that are composed of fibrous tissue, bacterial colonies, and inflammatory cells -> disruption of blood flow due to the vegetative masses and exposure of the platelets to non- endothelial covered surfaces -> activation of platelets and clotting factor -> formation of thrombi on the valve leaflets ? embolization of clot to the arcuate and interlobular arteries of the kidneys -> decreased blood flow (ischemia) and oxygenation (hypoxia) upstream of the obstruction -> coagulative necrosis (infarction)
Describe this lesion. History: tissue from a 3.5 month old angus calf. The patient presented with diarrhea, severe bruxism, and metabolic acidosis.
There were multifocal to coalescing pale, yellow to white, firm, smooth, nodules, ranging from 0.5-1 cm in size, on the renal cortical surface and extending into the parenchyma. There are white streaks extended from renal pelvis to the capsular surface.
Give a morphological diagnosis.
Kidney: severe, subacute to chronic, multifocal to coalescing, pyelonephritis
What are some possible mechanisms for the occurrence of this lesion?
ascending infection from the lower urinary tract or hematogenous route from septicemia
Describe this lesion. History: tissue from a 4 year old ewe. The patient presented with a history of weight loss andenlarged prescapular lymph nodes.
Multifocally, the renal cortex and corticomedullary junction contained encapsulated, round nodules that are approximately 2 - 3 cm in diameter, and contained a creamy tan semi-viscous material.
Give a morphological diagnosis.
Kidney: multifocal chronic renal abscesses
Describe this lesion. History: tissue from a 7 month old male suffolk ram.
the kidney was diffusely dark blue/brown
Give a morphological diagnosis.
Kidney: diffuse hemoglobinuric nephrosis (nephropathy)
What is likely the cause of this disease?
copper toxicosis due to excessive dietary copper
What is the pathogenesis of this lesion?
Copper gets stored in the hepatocytes and under periods of stress causes hepatocellular necrosis with liberation of copper into the circulation. This causes acute hemolysis, which results in hemoglobinemia and, once the renal threshold is exceeded, hemoglobinuria. Hemoglobin accumulates in the lumen of the renal tubules during this process causing the bluish/brown discoloration of the kidney (historically referred to as gun-metal blue color).
Describe this lesion. History: tissue from an 8 year old spayed female dog. The dog had a history of chronic splenitis and hepatitis.
Diffusely, the kidney surface was pale and nodular. The cut surface was pale and had a thin renal cortex with a slightly dilated renal pelvis.
Give a morphological diagnosis.
Kidney: chronic, diffuse, renal amyloidosis
In addition to the presence of interstitial fibrosis, histopathology showed expansion of glomerular tufts by amorphous hyaline substance that is congophilic. Name the lesion and describe the pathogenesis.
This is renal glomerular amyloidosis that often occurs secondary to chronic inflammatory disease. Chronic inflammation can stimulate the production of serum amyloid associated (SAA) protein that is metabolized by mesangial cells to AA protein fragments that will spontaneously polymerize to form amyloid fibrils. Amyloid then accumulates within the mesangial region of the glomerulus and disrupts the glomerular filtration apparatus causing proteinuria and ultimately nephron loss and renal fibrosis with CRF.
What would be the abnormal clinical laboratory data associated with the gross and histopathological changes?
increased BUN, creatinine, phosphorus; non-regenerative anemia; decreased bicarbonate. Proteinuria in the UA
Describe this lesion. History: tissue from a 5 year old warm blood horse. The patient had a history of weight loss and was diagnosed with chronic renal failure prior to euthanasia.
Kidney: the entire kidney was approximately 60% of normal size. The cortex and medulla were shrunken in size and the renal pelvis was dilated and filled with mucus. Numerous green/brown calculi of varying sizes, from sand particle to 6 cm in diameter, were occupying 90% of the dilated renal pelvis.
Give a morphological diagnosis.
Kidney: chronic, focal, moderate hydronephrosis and nephrolithiasis with renal pelvis mucous accumulation
What is the general term for increased nitrogenous waste in the blood?
azotemia
Describe this lesion. History: tissue from a 2 year old male sheep that had stopped drinking water for an extended period of time.
Urinary bladder: Both the mucosal and serosal surfaces had multifocal areas of dark red discoloration involving approximately 25% of the surfaces. Kidney: The kidney appeared slightly enlarged. The renal pelvis, including the major and minor calyces, was mild to moderately dilated. The sub-capsular surface of the kidney contained random pale-colored irregular patchy areas circumscribed by a red zone.
Give a morphological diagnosis for the bladder.
urinary bladder: severe, acute, multifocal cystitis
Give a morphological diagnosis for the urethra.
urethra: severe, acute, locally extensive hemorrhagic urethritis
Give a morphological diagnosis for the kidney.
Kidney: mild hydronephrosis and mild to moderate, acute, multifocal pyelonephritis
Describe this lesion. History: tissue from a 1 year old male feline with chronic diarrhea, weight loss, and lethargy.
Kidney: The kidney is slightly enlarged and the cortical surface contains multifocal to coalescing small yellow nodular areas that are approximately 1 mm in diameter and track along vessels. The areas extend into the cut surface with multiple similar foci in the cortex, corticomedullary junction and medulla.
Give a morphological diagnosis.
Kidney: chronic, multifocal, nodular nephropathy
List possible differential diagnoses.
feline infectious peritonitis, toxoplasmosis, lymphoma, metastatic neoplasm
Describe this lesion. History: tissue from a 10 year old rat terrier with a 2 month history of vaginal discharge.
Urinary bladder: the bladder wall was thickened and had mottled dark brown discoloration of the mucosal surface. There were 2 white, smooth, spherical uroliths in the lumen, and a large amount of white/pale yellow sand in the lumen and adhered to the mucosa, especially near the entrances of the ureters.
Give a morphological diagnosis.
Bladder: chronic, diffuse, cystitis with severe urolithiasis
Make a list of possible sequelae to this lesion.
Urinary obstruction to hydroureter/hydronephrosis to urinary bladder rupture or bacterial infection + urinary stasis to ascending infection to pyelonephritis
Describe this lesion. History: tissue from a 7 year old castrated dog.
Bladder: There were pink and gray locally extensive proliferative masses located at the trigone of the urinary bladder. The proliferations at the trigone of the bladder were only evident once the bladder was opened. The multifocal nodular masses were soft and ranged in size from 0.5 - 2 cm. There were also white multifocal miliary nodules on the mucosa diffusely throughout the bladder.
Given the location of the lesions, what is the most likely diagnosis?
transitional cell carcinoma - classically observed as a mass arising from the trigone or prostatic urethra
List one complication that may occur with this lesion given its location.
a mass in the trigone of the bladder can cause obstruction, possibly leading to hydroureter, hydronephrosis, and azotemia.
Describe this lesion. History: tissue from a 12 year old cat.
Kidney: The cortical surface of both kidneys contained multifocal to coalescing small yellow nodules that were approximately 1-10mm in diameter.
Give a morphological diagnosis.
Kidney: chronic, multifocal, nodular nephropathy
List possible differential diagnoses for this case.
Neoplasm: renal lymphoma or metastatic neoplasm. Infectious: granulomas (FIP), toxoplasmosis
Describe this lesion. History: tissue from an 18 year old female cat with a history of chronic renal failure
Stomach: The gastric mucosa was diffusely red and had multifocal 1- 2mm in diameter circular lesions with a gritty texture. Kidney: the left kidney appeared enlarged, on cut surface there was a mild amount of cortical hemorrhage. The right kidney was markedly smaller (2.2 cm x 0.7 cm) then the left kidney. The surface of the right kidney was lobulated. On cut surface, there was a delineated cortex and medulla.
Give a morphological diagnosis for the stomach.
Stomach: Chronic, multifocal to coalescing, mineralization
Give a morphological diagnosis for the left kidney.
moderate renal hypertrophy
Give a morphological diagnosis for the right kidney.
severe hypoplasia
Give the most likely pathogenesis for these lesions.
Endothelial damage and vasculitis caused by uremic toxins from chronic renal failure. This can result in multifocal muscosal ischemia and necrosis at various locations. Injured cells within the mucosa of various tissue tend to mineralize.
Describe this lesion. History: Tissue from an 11 year old quarter horse gelding with a several month history of weight loss and a recent elevation in BUN and creatinine.
Kidney: The kidney is markedly enlarged and the capsular surface of the kidney was markedly irregular and slightly elevated with multifocal and coalescing regions of pallor. On cut surface, the regions of pallor extended from the cortex into the medulla where multifocal and coalescing poorly circumscribed nodular lesions were present. In these areas the distinction between the cortex and the medullary regions of the kidney parenchyma was frequently lost. Some of these nodules were organized around central cystic cavitated areas (1-10 mm diameter).
Histology revealed multiple small nodular accumulations of macrophages, multinucleate giant cells, eosinophils, lymphocytes and plasma cells surrounding cross-sections of nematodes. This exudate obliterated much of the cortical parenchyma. Given the histologic finding, give a morphologic diagnosis.
Kidney: Chronic, severe, multifocal to coalescing, interstitial granulomatous nephritis with intralesional nematodes
Describe this lesion. History: tissue from a large (+/- 60lbs) dog with small-size kidneys and hyperparathyroidism.
Kidneys: Both kidneys are small and pale with irregular cortical surfaces. The consistency is firm and there are pin-point white grainy foci throughout the renal parenchyma. Also, the renal pelvises are modestly dilated.
Give a morphological diagnosis.
Kidney: diffuse, bilateral, renal fibrosis with mild hydronephrosis
What lesions in other organs might you find associated with this lesion?
oral and gastrointestinal mucosal ulceration, fibrinoid vascular necrosis, soft tissue mineralization, fibrous osteodystrophy from renal secondary hyperparathyroidism
