Clinical Pathology Flashcards
Covers - Urinalysis, Proteinuria, and Azotemia lectures
How do polyuria and diuresis differ?
(They are both an increase in urine production but polyuria is due to a pathologic process and diuresis is due to a non-pathologic process)
What is pollakiuria?
(Increased frequency of urination with a normal urinary volume)
What is the term for decreased urine production and can be due to both pathologic and non-pathologic processes?
(Oliguria)
What is the term for minimal to no urine production?
(Anuria)
If you delay analyzing a urine specimen, the pH will increase or decrease (choose one).
(Increase)
If you delay analyzing a urine specimen, the USG will increase or decrease (choose one).
(Increase)
What is the usual USG value range for a euhydrated dog?
(1.015-1.045)
What is the usual USG value range for a euhydrated cat?
(1.035-1.065)
What is the usual USG range for a euhydrated horse?
(1.020-1.050)
What is the usual USG range for a euhydrated cow?
(1.025-1.045)
(T/F) USG and urine volume have an inversely proportional relationship i.e. if your urine output is low, your USG will be higher and vice versa.
(T)
Leukocytes; nitrite; urobiligen; protein; pH; blood; USG; ketones; bilirubin; glucose
In the list of tests on the human dipstick above, which are unreliable for animal urine?
(Leukocyte/WBC, nitrite, urobilinogen, and USG)
What can cause aciduria? Two answers.
(Acidosis (metabolic or respiratory) and paradoxical aciduria resulting from hypochloremia metabolic alkalosis (i.e. vomiting a lot that causes alkalosis can result in a paradoxical aciduria))
What is an alkaline tide?
(An increase in pH after meals in monogastric animals)
(T/F) Normal urine should not contain any glucose.
(T)
What cleaning products can cause a false positive glucosuria?
(Bleach and hydrogen peroxide)
(T/F) Ketones should not be present in the urine of healthy animals.
(T)
If you have a proteinuria determined via dipstick but the urine was also alkaline as per the dipstick, what test do you need to run to confirm the proteinuria is not a false positive?
(SSA test)
What is overflow proteinuria?
(Massive excretion of low molecular weight proteins → myoglobin, hemoglobin, Bence-Jones proteins, and colostrum)
What type of proteinuria do tubulointerstitial nephritis, Fanconi syndrome, nephrotoxins, acute kidney insufficiency, and chronic kidney disease cause?
(Tubular proteinuria: tubular dysfunction → impaired reabsorption of LMW proteins)
What causes post-renal proteinuria?
(Inflammation or hemorrhage → pyelonephritis, cystitis, urinary tract neoplasia, urolithiasis, FLUTD/FIC, prostatitis/vaginitis, etc.)
What type of proteinuria is characterized by the leakage of high molecular weight proteins primarily albumin?
(Glomerular proteinuria: glomerular disease (glomerulonephritis, hypertension, CKD, amyloidosis, membranous nephropathy) → leakage of HMW proteins)
What is the use of a urine protein creatinine ratio test?
(UPC is used to detect glomerular or tubular disease)
When should a UPC not be used?
(If there is active urine sediment or if there is hemoglobinuria or myoglobinuria)
How can you determine if the proteinuria your patient has is glomerular versus tubular?
(Glomerular proteinuria will result in a UPC >3 while tubular will have a UPC between 0.5-3)
Does glomerular or tubular proteinuria lead to hypoalbuminemia?
(Glomerular)
What are the four criteria for nephrotic syndrome?
(Proteinuria, hypoalbuminemia, hypercholesterolemia, and edema)
What type of pre-renal proteinuria is seen with multiple myeloma?
(Bence-Jones proteinuria → overflow proteinuria)
What test can be performed to detect Bence-Jones proteinuria?
(Urine protein electrophoresis and immunofixation)
(T/F) It is normal to see squamous epithelial cells in free-catch and catheterized urine specimens.
(T but should be 0/lpf in a cystocentesis sample)
Why does the presence of bacteria in the urine increase urine pH?
(Bacterial urease breaks urea down into ammonia which will increase urine pH)
What does increased cyllindruria indicate?
(Renal tubular damage)
What are the three types of crystals that are normally present in the urine of dogs and cats?
(Amorphous, small amounts of calcium oxalate mono/dihydrate, triple phosphate/struvite crystals)
What diseases/disorders are indicated by the presence of ammonium urate crystals in urine?
(Portosystemic shunt and/or liver insufficiency)
High numbers of calcium oxalate monohydrate crystals are associated with what toxicity?
(Ethylene glycol intoxication)
(T/F) Crystals in urine typically means there is a urolith.
(F, crystals in urine do not mean there are uroliths)
How can you determine the composition of the uroliths your patient has?
(Send it out for evaluation, this is the only way!)
What is the term for increased non-protein nitrogenous compounds in the blood?
(Azotemia, specifically urea nitrogen and creatinine)
What is uremia?
(Clinicals signs associated with renal failure → vomiting, diarrhea, coma, convulsions, ammonia odor to breath)
What non-renal causes can increase a patient’s BUN?
(GI hemorrhage or a high-protein diet)
How does liver insufficiency impact BUN values?
(It will decrease them because the liver converts ammonia to urea so if it is insufficient, that occurs at a lower rate and will decrease BUN)
What are two cases in which an increased urine creatinine is expected?
(Healthy greyhounds (high muscle mass) and neonatal foals born to dams with a dysfunctional placenta (this should diminish rapidly after birth, if it doesn’t then that indicates a renal issue))
Prerenal azotemia is characterized by increased BUN and/or creatinine, hyper or hyposthenuria (choose one), and a quiet urine sediment.
(Hypersthenuria)
What are the three causes of prerenal azotemia?
(Decreased renal perfusion → dehydration, hypovolemia, cardiac insufficiency, shock, and blood loss; increased protein metabolism/catabolism → fever, starvation, necrosis, GI bleeding, hyperadrenocorticism; and decreased plasma oncotic pressure → severe hypoalbuminemia)
Renal azotemia is characterized by increased BUN and/or creatinine, a quiet urine sediment, and what kind of urine concentration? Two answers.
(Isosthenuria or minimally concentrated urine)
Post-renal azotemia is characterized by increased BUN and/or creatinine, a variable USG, and what on sediment?
(Depends on lesions location and duration → hematuria, casts, renal cells)
What electrolyte abnormalities are associated with post-renal azotemia?
(Hyponatremia, hypochloremia, hyperkalemia, and hyperphosphatemia)
What are water deprivation and ADH response tests used for?
(Non-azotemia patients with PU/PD and hyposthenuria → differentiates psychogenic polydipsia, central diabetes insipidus, nephrogenic diabetes insipidus and medullary washout)
What are three causes for nephrogenic diabetes insipidus (a non-renal disease which decreases the kidneys response to ADH)?
(Hypercalcemia, canine pyometra, and hypokalemia)
