Lecture 21 - Urinalysis Flashcards
1
Q
WATCH THIS LECTURE WHILE STUDYING
What are you evaluating when performing a urinalysis?
–> Evaluating what the kidney is _______ provides insight into:
1. ______ Function
2. _______ Disease
3. ________ Disease
A
–> Evaluating what the kidney is excreting provides insight into:
1. Renal Function
2. Metabolic Disease
3. Systemic Disease
2
Q
What are the indications for a urinalysis?
A
–> Indications:
1. Health screening
2. Pre-anesthetic assessment
3. Key element to the minimum database
3
Q
Performing a Urinalysis:
1. Cost?
2. ________ performed in-house
3. Requires _______ specialized equipment
A
Performing a Urinalysis:
1. Cost? Inexpensive
2. Easily performed in-house
3. Requires minimal specialized equipment
4
Q
What is important about your urinalysis technique?
–> ________ of sample collection
- Early ________ → more concentrated
- Post- _______ → more alkaline
- After fluid or diuretic therapy → more ______
–> There are 3 options for collection:
1. _______ sample or “free ______”
2. Urinary _______
3. ___________
(1–>3 is least to most expensive)
A
–> Timing of sample collection
- Early morning → more concentrated
- Post- prandial → more alkaline
- After fluid or diuretic therapy → more dilute
–> There are 3 options for collection:
1. Voided sample or “free catch”
2. Urinary catheterization
3. Cystocentesis
(1–>3 is least to most expensive)
5
Q
What is a voided sample?
- _________ sample
* Catch ______-stream flow
* __________ acceptable for urinalysis
* Not suitable for _______
- __________ contamination!
A
- Voided sample
* Catch mid-stream flow
* Generally acceptable for urinalysis
* Not suitable for culture
- Bacterial contamination!
6
Q
- Urethral Catheterization
* Acceptable for ________ and ______
- May have _____ or ________ cell contamination
* _________ invasive
* Technically difficult, especially in ________
Performed under ______ techniques
Risk introducing _______ into the bladder
A
- Urethral Catheterization
* Acceptable for urinalysis and culture
- May have blood or epithelial cell contamination
* Moderately invasive
* Technically difficult, especially in females
Performed under sterile techniques
Risk introducing bacteria into the bladder
7
Q
- Cystocentesis
- Pass a needle _______ into the bladder- Often _______-guided
- ______ technique
- Acceptable for ________ - ________ contamination
Ideal for urine _________
A
- Cystocentesis
- Pass a needle directly into the bladder- Often ultrasound-guided
- Sterile technique
- Acceptable for urinalysis - Blood contamination
Ideal for urine culture
8
Q
How are you supposed to handle a urine sample?
- Ideally analyze within ____ ________
- Low USG can lead to _________ _____
- May have urine crystals ______ or _________ - If longer time for analysis, refrigerate
- Up to ____ _______
- _______, _________, __________ container
- _______ to _______ temperature prior to analysis
- Be sure to gently _________ the sediment
A
- Ideally analyze within 30 minutes
- Low USG can lead to cellular lysis
- May have urine crystals dissolve or develop - If longer time for analysis, refrigerate
- Up to 12 hours
- Sterile, opaque, airtight container
- Warm to room temperature prior to analysis
- Be sure to gently re-suspend the sediment
9
Q
List the steps of a complete UA
A
- Gross inspection
- USG
- Chemical evaluation
10
Q
List the probable causes for the following urine colors:
A
See below
11
Q
List the levels of clarity of urine
What is cloudiness caused by?
A
See below
12
Q
What does the USG evaluate?
A
Evaluates for dissolved molecules… “solutes”
13
Q
What is important to remember in regards to the USG?
Remember:
Measure urine samples only at ______-temperature
- Cold fluids are more _____, falsely ______ USG
Remember: Significant INCREASES in (4?) in the urine can INCREASE the USG
–> Hypersthenuria (concentrated urine):
A. Dogs = ?
B. Cats = ?
C. Horses/ruminants/porcine = ?
–> Isosthenuric: USG = ?
- Kidney is not adjusting urine concentration (non _________ nor _______)
–> Range of minimal concentration (ROMC):
A. Dogs = ?
B. Cats = ?
C. Horses/ruminants/porcine = ?
–> Oliguric: ____ urine output
–> Azotemic: Increased ___ and/or ______
A
Remember:
Measure on room-temperature urine only
Cold fluids are more dense, falsely increases USG
Remember: Significant INCREASES in glucose, protein, sodium and/or urea in the urine can INCREASE the USG
Answer: 1.033 hypersthenuria (concentrated urine) in dogs, remember above 1.030, cats above 1.035, horses/ruminants/porcine above 1.025
Remember, 1)Isosthenuric: USG 1.008-1.012: Kidney is not adjusting urine
concentration (non concentrating nor diluting)
2) Range of minimal concentration (ROMC) : 1.013-1.030 Dog; 1.013-1.034
Cat; 1.013-1.024 Equine, Ruminants, Porcine
3)Oliguric: no urine output 4)azotemic: Increased BUN and/or Creatinine
14
Q
Evaluate the image below
A
D
15
Q
What type of measurement is the Dipstick test?
A
Semi-quantitative measurement
16
Q
What scale is used for the Dipstick test?
A
Scale: neg → trace → 1+ → 2+ → 3+ → 4+
17
Q
What does the dipstick measure? What does it not measure?
A
Measures:
Glucose, Bilirubin, Ketones, Heme, pH, Protein
Ignore: Leukocytes, USG, Nitrite, Urobilinogen
18
Q
What is important about the dipstick test?
A
timing!
19
Q
A
20
Q
How are the Chemical constituents of urine measured?
A
Most often measured with a urine dipstick
21
Q
A Urine dipstick is Semiquantitative: most analytes graded on
negative to 4+ scale
A
22
Q
What dipstick tests are used in veterinary medicine?
A
- Dipstick tests we use in veterinary medicine:
– Glucose
– Bilirubin
– Ketones
– Blood
– pH
– Protein
23
Q
What dipstick tests do we NOT use in veterinary medicine?
A
– USG
– Leukocytes
– Nitrite
– Urobilinogen
– Ascorbic acid
24
Q
Glucose:
_______ molecule
__________ filtered by the glomerulus
Usually completely reabsorbed in ______ tubules
A
Glucose:
Small molecule
Freely filtered by the glomerulus
Usually completely reabsorbed in proximal tubules
25
Glucosuria
Occurs when the __________ capacity is exceeded
Dog ___ mg/dL
Cat ____ mg/dL
Horse _____ mg/dL
Cattle _____ mg/dL
Glucosuria
Occurs when the reabsorption capacity is exceeded
Dog 220 mg/dL
Cat 280 mg/dL
Horse 180 mg/dL
Cattle 100 mg/dL
26
What are the common differentials for glucosuria?
Differentials for glucosuria: HAD Stress God Can Feel
Most common: Hyperglycemic glucosuria
Diabetes mellitus
Acute pancreatitis
Stress (corticosteroids) especially in cats
Glucose-containing fluids
27
What are the less common differentials for glucosuria?
Less common: Normoglycemic glucosuria
1. Acute kidney injury
- Reversible tubular damage: drugs, toxins, etc.
- Urethral obstruction in cats (unknown mechanism)
2. Fanconi syndrome (Basenjis, Labrador Retrievers)
Fanconi Syndrome: Proximal tubular defect that causes impaired tubular reabsorption of glucose, amino acids, and phosphate
– Results in proteinuria and glucosuria with normoglycemia • Can be congenital or acquired
– Congenital: Basenjis (30% of breed)
• Dogs are typically 3-4 years old when first diagnosed
– Acquired: chicken jerky treat recall, copper storage disease, heavy metal toxicity
28
Bilirubin is a product of erythrocyte ________ degradation (________ form) that becomes ________ in the liver
Bilirubin is a product of erythrocyte hemoglobin degradation (unconjugated form) that becomes conjugated in the liver
29
*Unconjugated bilirubin circulates bound to _______ and ________ pass through the glomerulus
*Unconjugated bilirubin circulates bound to albumin and cannot pass through the glomerulus
30
*____________ bilirubin passes through the glomerulus and is not _________ by the tubules
*Conjugated bilirubin passes through the glomerulus and is not reabsorbed by the tubules
31
*Bilirubinuria precedes _________ due to low renal threshold
bilirubinemia
32
*Usually normal to see trace to ____ __________ in dogs with concentrated urine
1+ bilirubinuria
33
*No _________ should be present in cats and is always ________
bilirubinuria, abnormal
34
*May or may not see concurrent bilirubin crystals in the urine
35
Bilirubinuria:
– Indicates _________ of ____ flow and regurgitation of ________ bilirubin into the ____
Bilirubinuria:
– Indicates obstruction of bile flow and regurgitation of conjugated bilirubin into the blood
36
Bilirubinia leads to an ________ tubular cell formation of bilirubin in cases of
hemoglobinuria
* Increased hepatic ________ of bilirubin in cases of intravascular __________
– _____
– ______ ____ leaf, _____, _______, ________ toxicity
Increased tubular cell formation of bilirubin in cases of
hemoglobinuria
* Increased hepatic conjugation of bilirubin in cases of intravascular
hemolysis
– IMHA
– Red maple leaf, onion, garlic, acetaminophen toxicity
37
In a case of bilirubinuria, – False _______ on the dipstick test can occur with ___________ sample processing or excessive _____ exposure
In a case of bilirubinuria, – False negative on the dipstick test can occur with delayed sample processing or excessive light exposure
38
Ketones (3?) are produced when energy production shifts from __________ to _____ metabolism. They are filtered by the ________, excreted in _______.
Ketones (β-hydroxybuterate, acetoacetate, acetone) are produced when energy production shifts from carbohydrate to lipid metabolism. They are filtered by the glomerulus, excreted in urine
39
What ketones do urine dipsticks detect?
Detects _________ and ______ (_____ ketones); does not detect ____________.
- _______ of ketonuria may be underestimated!
Detects acetoacetate and acetone (true ketones); does not detect β-hydroxybuterate
- Magnitude of ketonuria may be underestimated!
40
Ruminants produce mostly what type of ketone?
Ruminants produce mostly β-hydroxybuterate
41
Ketonuria
- ____________ _________ (_____) dogs and cats
- __________ energy balance (starvation)
- Diabetes ________ (Diabetic _________)
- _______ in cattle
Ketonuria
- Diabetic ketoacidosis (DKA) dogs and cats
- Negative energy balance (starvation)
- Diabetes mellitus (Diabetic ketoacidosis occurs in type 1 diabetes mellitus, less common in type 2)
- Ketosis in cattle
42
The dipstick heme/blood detects?
Intact red blood cells, hemoglobin, or myoglobin
43
List the DDx for Hematuria.
DDX Hematuria:
Inflammation,
Infection,
Trauma,
Coagulopathy,
etc.
44
What is the most common cause for finding intact rbc, hemoglobin, or myoglobin in blood?
Hematuria (RBCs)
The most common cause
Supernatant clears with centrifugation
Hematuria --> red, cloudy urine that clears after centrifugation: Should see RBC pellet in
centrifuged tube and usually RBCs on sediment exam
45
Define pigmenturia.
Pigmenturia (HGB, MGB)
Supernatant remains red with centrifugation
46
1. Define hemoglobinuria. What should you look for?
2. Hemoglobinuria –> ____ urine that _____ _____ ____ after centrifugation
– Usually no RBC pellet in ________ tube
– If hemoglobinuria is due to intravascular hemolysis, will also see _________ (red ______)
Hemoglobinuria = hemolysis
Look for anemia, pink/red serum
Hemoglobinuria --> red urine that does not clear after centrifugation
– Usually no RBC pellet in centrifuged tube
– If hemoglobinuria is due to intravascular hemolysis, will also see hemoglobinemia
(red plasma)
47
1. Define myoglobinuria. What should you look for?
2. Myoglobin --> _____-_____ urine that ______ _____ _____ after centrifugation
– Clinical evidence of ______ disease
– Usually elevated __________ _____ on chemistry panel
Myoglobinuria = muscle injury
Look for increased muscle enzymes (CK, AST)
Myoglobin --> red-brown urine that does not clear after centrifugation
– Clinical evidence of muscle disease
– Usually elevated Creatinine Kinase on chemistry panel
48
The Dipstick pH approximates?
urine pH.
It is not precise.
49
What is the normal urine pH in dogs and cats?
5.0-7.5
50
Urine pH varies with?
Type of _____
Collection ____ (post-_____ vs. post-______)
Systemic ______-_____ status
Type of diet
Collection time (post-fasting vs. post-parandial)
Systemic acid-base status
51
How does urine become acidic?
The Ph affects the types of casts and crystals, and uroliths
Paradoxical aciduria with alkalosis: acidic urine (aciduria) in the face of a metabolic alkalosis
52
How does the urine become alkaline?
1. ______ protein-based diet
2. __________ alkaline tide
3. ____ with _______-containing (______ producing) bacteria
4. Urine sample exposed to ____ at _____ temperature
5. Use of _______ agents
6. _______ and _______ alkalosis
1. Plant protein-based diet
2. Postprandial alkaline tide
3. UTI with urease-containing (ammonia producing) bacteria
4. Urine sample exposed to air at room temperature
5. Use of alkalinizing agents
6. Metabolic and respiratory alkalosis
53
The dipstick protein test primarily detects?
Primarily detects albumin (negative charge)
54
Describe the sensitivity and specificity of the dipstick protein test.
Low sensitivity and low specificity
55
Are false positives common in dipstick protein tests? If so, list the common reasons
False positives are common, especially in:
Alkaline urine
Cats due to an albumin-like protein, cauxin
Hypersthenuria
56
What are the false negatives with a dipstick protein test?
Has a lower limit of ____-____ mg/dL of albumin
Insensitive to ____ and _______-_____ proteins
Has a lower limit of 20-30 mg/dL of albumin
Insensitive to globulins and Bence-Jones proteins
57
What do you do if you see a positive protein reaction test in a dipstick protein test?
Positive protein reaction... FIRST:
1. r/o Hemorrhage
- Positive blood reaction
- Will see RBCs in sediment
2. r/o UTI / Cystitis
- Will see bacteria & WBCs on sediment
3. r/o Intravascular hemolysis- hemoglobinuria
- Hgb is a protein
- Animal will be anemic
58
Proteinuria caused by renal disease:
1. Blood reaction will be _________ (usually)
2. Measure a ________
Proteinuria with nothing in the sediment is most often indicative of ?
Proteinuria caused by renal disease:
1. Blood reaction will be negative (usually)
2. Measure a UPCR
Proteinuria with nothing in the sediment is most often indicative of glomerular disease
59
What is the Sulphosalicylic Acid Test (SSA) used for?
Used to confirm dipstick protein results
60
The SSA test reacts with?
Reacts with albumin, and also...
Reacts adequately with globulins/Bence-Jones
proteins
61
What will you need for the SSA test?
Urine ____________ + 5% ___________ acid
- _______ of sample is compared to standards
Urine supernatant + 5% sulphosalicylic acid
Turbidity of sample is compared to standards
62
Proteinuria
* Interpret the ______ and ______ together
* Along with the _______ and _________ panel
* And don’t forget about the _____ and presenting clinical ______!
Proteinuria
* Interpret the dipstick and Sulphosalicylic Acid Test together
* Along with the USG and chemistry panel
* And don’t forget about the patient and presenting clinical signs!
63
List the specific proteinuria disorders
* Nephrotic syndrome
* Fanconi syndrome
64
Nephrotic syndrome
* Rare complication of _______--> abdominal ________/________
– Clinical syndrome characterized by:
* _________
* ______________
* Peripheral ______ or ______ spacing of fluid (ascites)
* _______________
Nephrotic syndrome
* Rare complication of protein-losing nephropathy (PLN) --> abdominal effusion/transudation
– Clinical syndrome characterized by:
* Proteinuria
* Hypoalbuminemia
* Peripheral edema or third spacing of fluid (ascites)
* Hypercholesterolemia
65
Fanconi syndrome
* Proximal tubular defect that causes impaired tubular reabsorption of glucose, amino acids, and phosphate
– Results in proteinuria and glucosuria with normoglycemia
* Can be congenital or acquired
– Congenital: Basenjis (30% of breed)
* Dogs are typically 3-4 years old when first diagnosed
– Acquired: chicken jerky treat recall, copper storage disease, heavy metal toxicity
66
Describe the microscopic examination of sediment procedure.
1) Centrifuge at low speed for 5 minutes
2) Decant urine without disrupting the sediment; leave a small amount of urine
(~500 uL) for resuspension
3) Re-suspend the pellet
4) Transfer a drop to a glass slide and place a coverslip
5) Lower the condenser on the microscope
6) Examine the entire coverslip, especially the edges
1st evaluate at 10x: epithelial cells, crystals, casts
2nd evaluate at 40x: RBC, WBC, fat, microorganisms
67
What is the source of epithelial cells?
Squamous cells:?
Transitional cells:?
Caudate cells: renal ____ (RARE = ______)
Renal cells: renal ______ (RARE = renal ____ _____)
Squamous cells: distal urethra, vaginal tract, skin
Transitional cells: renal pelvis, ureter, bladder, proximal urethra
Caudate cells: renal pelvis (RARE = pyelonephritis)
Renal cells: renal tubules (RARE = renal tubular injury)
68
Squamous epithelial cells
- ______ in size, _____ in terms of thickness, often _________, ______ or _____
- Significance:
- Seen in _____ catch urine
- Rarely _________
- Sertoli cell tumors causing squamous _________
Squamous epithelial cells
- Large, thin, often transparent, angular or folded
- Significance:
- Seen in free catch urine
- Rarely pathologic
- Sertoli cell tumors causing squamous metaplasia
69
Squamous epithelial cells
70
Describe the morphological characteristics of transitional epithelial cells.
What is its significance?
Transitional epithelial cells
- _______ in shape, ______ in size, found _________ and in ________
- Significance:
- __________ associated with inflammation
- Transitional cell tumors (_______ and _____)
Transitional epithelial cells
- Round, vary in size, found individually and in clusters
- Significance:
- Hyperplasia associated with inflammation
- Transitional cell tumors (benign and malignant)
71
Transitional epithelial cells
72
Urine Sediment: Neoplastic Cells:
- Expert diagnosis... send to your clinical pathologist!
- Transitional epithelial cells respond to inflammation with highly variable in ____ and ______
- Easy to mistake ______________ for neoplasia!!
- ____-dried sediment / __________ preparations
- Usually obtained with _______; unusual to see on ________ samples
Urine Sediment: Neoplastic Cells:
- Expert diagnosis... send to your clinical pathologist!
- Transitional epithelial cells respond to inflammation with highly variable in size and morphology
- Easy to mistake inflammation for neoplasia!!!
- Air-dried sediment / cytocentrifuged preparations
- Usually obtained with catheterization; unusual to see on cystocentesis samples
73
Transitional cell carcinoma
74
Red blood cells (RBCs) seen in the urine of a
monkey passing a kidney stone. Some of the RBCs
are crenated and there is one epithelial cell visible.
(Courtesy of Richard P. Usatine)
75
Describe the morphological characteristics of RBCs on urine sediment. What is the significance.
________ in shape, often _______-tinged, may be __________
Significance: 2?
Remember: ______________ ___________ is expected on a cystocentesis sample
Red Blood Cells
Round, often yellow-tinged, may be crenated
Significance: Hemorrhage, Inflammation
Remember:Microscopic hematuria is expected on a cystocentesis sample
76
Describe the morphological characteristics of WBCs on urine sediment. What is the significance.
* ~___x larger than RBCs; cytoplasm looks _______
* <5 WBCs/hpf is usually considered ______
* >5 WBCs/hpf = ______
* General causes of pyuria:
– _______ tract infection – _______ or lower _______ tract
* Should ________ if UTI is suspected, even if no bacteria are _______!
– Non-infectious _______ – ____ (e.g., from calculi)
– ___________
– ___________
* ~2x larger than RBCs; cytoplasm looks granular
* <5 WBCs/hpf is usually considered normal
* >5 WBCs/hpf = pyuria
* General causes of pyuria:
– Urinary tract infection – pyelonephritis or lower urinary tract
* Should culture if UTI is suspected, even if no bacteria are visible!
– Non-infectious inflammation – cystitis (e.g., from calculi)
– Neoplasia
– Prostatitis
77
WBC on urine sediment
78
How can you see bacteria on urine sediment?
>10,000 rods/mL
>100,000 cocci/mL
79
What is the standard for detecting bacteria on urine sediment?
No standard method for reporting
- Few to many
- Present vs. Absent
80
What do you expect to see in a urine sediment contains bacteria?
Neutrophils
- Unless immunosuppressed
- steroid therapy, Cushing’s,
diabetic, FIV cat, etc.
81
Describe the culture selection for UTIs
- _______ organisms
- ___________ measurement
- Sensitivity with _____
- Aerobic organisms
- Quanitative measurement
- Sensitivity with MIC
82
Urine sediment: bacteria
83
What other infectious organisms can be seen on a urine sediment?
Significance? Are there clinical signs?
What was the method of collection?
- Voided (fecal contamination?)
Sample storage
- Where was the sample stored?
- How long was the sample stored?
I s the patient immunosuppressed?
Do other diagnostic findings support infection?
84
85
86
87
List the in vivo factors that Contribute to Urine Crystal Formation
1. ________ and ________ of crystalline material
2. Urine ____
3. ______
4. Excretion of ____ or _________ _______ agents
1. Concentration and solubility of crystalline material
2. Urine pH
3. Diet
4. Excretion of drugs or diagnostic imaging agents
88
List the in vitro factors that Contribute to Urine Crystal Formation
Temperature - solubility _______ with decreased temperature
__________ - increases the solute concentration
Urine pH - changes with ________ urine and bacterial _________
Temperature - solubility decreases with decreased temperature
Evaporation - increases the solute concentration
Urine pH - changes with standing urine and bacterial overgrowth
89
List the common crystals
"CCABS"
Amorphous
Bilirubin
Calcium carbonate
Calcium oxalate dihydrate
Struvite
90
List the uncommon crystals
"CCADO"
Ammonium bitrate
Calcium oxalate monohydrate
Cysteine
Drug-associated
Other
91
Describe the typical appearance of amorphous urinary crystals. Significance?
Typical appearance:
Yellow to yellow-brown
Aggregates of finely granular
material
No defining shape
Significance
None
92
What can be seen in the image below?
Amorphous
93
Describe the typical appearance of struvite urinary crystals. Significance?
Struvite (aka. triple ________ or _________ _________ phosphate)
Typical appearance:
- _______ in size, ______ in color, ______-like crystals (“______ lids”)
- Most common crystal in ____ and ____
- Formation is favored in ______ to _______ pH
--> Significance
- Can be found in clinically _______ patients
- Urease-_________ bacteria promote formation (↑urine pH)
Struvite (aka. triple phosphate or magnesium ammonium phosphate)
Typical appearance:
Large, colorless, prism-like crystals (“coffin lids”)
Most common crystal in dogs and cats
Formation is favored in neutral to alkaline pH
Significance
Can be found in clinical normal patients
Urease-positive bacteria promote formation (↑urine pH)
94
What can be seen in the image below?
Struvite
95
Describe the typical appearance of bilirubin urinary crystals. Significance?
Bilirubin
Typical appearance:
- ________ to _______ granules
- Usually present in small _______
Significance
- Dogs: low numbers in _____ concentrated urine is normal.
- _________ in all other species: _______
- pre-hepatic ... hemolysis (EVH)
- hepatic/post-hepatic ... hepatobiliary disease
Bilirubin
Typical appearance:
- Orange to copper granules
- Usually present in small bundles
Significance
- Dogs: low numbers in highly concentrated urine is normal.
- Abnormal in all other species: ICTERUS
- pre-hepatic ... hemolysis (EVH)
- hepatic/post-hepatic ... hepatobiliary disease
96
What can be seen in the image below?
Bilirubin
97
Describe the typical appearance of calcium carbonate urinary crystals. Significance?
Typical appearance:
- Large ______ with ______ striations
- _____-sized
- _______ to _____-_____ in color
Significance
- NORMAL in ?
- No reports in _______ or ______ urine
Typical appearance:
- Large spheres with radial striations
- Variably-sized
- Colorless to yellow-brown
Significance
- NORMAL in horses, rabbits, guinea pigs, and goats
- No reports in canine or feline urine
98
What can be seen in the image below?
Calcium carbonate
99
Describe the typical appearance of calcium oxalate dihydrate urinary crystals. Significance?
Calcium oxalate dihydrate
Typical appearance: “________”
- ______ squares connected by intersecting lines
- _____ in size
Significance
- _______ in domestic animals
- ________ artifact
Pathologic:
- ___________ _________ are predisposed
- __________ causing increased calcium excretion
- _______ renal failure
Calcium oxalate dihydrate
Typical appearance: “envelope”
- Colorless squares connected by intersecting lines
- Vary in size
Significance
- NORMAL in domestic animals
- Storage artifact
Pathologic:
- Miniature Schnauzers are predisposed
- Hypercalcemia causing increased calcium excretion
- Acute renal failure
100
What image can be seen below?
Calcium oxalate dihydrate
101
Describe the typical appearance of ammonium bitrate urinary crystals. Significance?
Typical appearance: “Thorn _______”
- ________ spheres
- _______ or _______-brown
Significance
- Normal finding in ______, _______ ________
- Pathologic: Suggests ______ disease; associated with ↓_____ , ↑ _____
- _______ Failure
- __________ or ________ shunts
Typical appearance: “Thorn apples”
- Spiked spheres
- Brown or yellow-brown
Significance
- Normal finding in Dalmations, English bulldogs
- Pathologic: Suggests liver disease; associated with ↓ B U N , ↑ N H 3
- Liver Failure
- Congenital or acquired shunts
102
What image can be seen here?
Ammonium bitreate
103
Describe the typical appearance of Calcium oxalate monohydrate urinary crystals. Significance?
Typical appearance:
- ______ (“____-____”), oval (“____ _____”) or dumbbell
- ____ in size: usually ____ and ____
Significance
- Can be seen in _______ animals, especially ______
- Pathologic:
- Oxalate urolithiasis
- Hypercalciuric or hyperoxaluric disorders
- Ehtylene glycol toxicosis (rare)
Typical appearance:
- Spindle (“picket-fence”), oval (“hemp seed”) or dumbbell
- Vary in size: usually small and colorless shaped
Significance
- Can be seen in healthy animals, especially horses
- Pathologic:
- Oxalate urolithiasis
- Hypercalciuric or hyperoxaluric disorders
- Ehtylene glycol toxicosis (rare)
104
Calcium oxalate monohydrate
105
Describe the typical appearance of cystine urinary crystals. Significance?
Typical appearance:
- ____ in terms of thickness, _________ in color ________ plates
- Often aggregate in _______
Significance
- Inherited disease: __________
- Defective renal tubular resorption of certain _______ ______
- Occurs almost exclusively in _____ dogs
- Many breeds affected
- Renal function is otherwise _______
Typical appearance:
- Flat colorless hexagonal plates
- Often aggregate in layers
Significance
- Inherited disease: Cystinuria
- Defective renal tubular resorption of certain amino acids
- Occurs almost exclusively in male dogs
- Many breeds affected
- Renal function is otherwise normal
106
Cystine
107
Describe the typical appearance of Drug-associated crystals. Significance?
Correlate with history!!!
Vary in appearance and size
- Frequently light to dark brown
- Commonly form needles arranged into sheaves, bundles, fans, and radiating spikes
Most drugs excreted in urine can form crystals
- Antibiotics: sulfa family drugs, ampicillin, ciprofloxacin, etc.
- Anticonvulsants: especially during poly therapy and in alkaline urine
- Allurinol administration
- Radiographic contrast media
108
This material is FYI
FYI
109
Casts are composed of_______-______ protein, a mucoprotein secreted by the tubular epithelium.
Tamm-Horsfall protein, a mucoprotein secreted by the tubular epithelium
110
Casts are formed in what parts of the body?
– Formed in loops of Henle, distal tubules, and collecting ducts
111
Casts are formed in ______ urine, may dissolve in _______ urine
* Formed in acidic urine, may dissolve in alkaline urine
112
The formation of casts is dependent on?
* Formation is dependent on urine acidity, solute concentration, and flow rate
113
Cats may be intermittently shed and may break down during urine sedimentation
* May indicate tubular damage and/or urine stasis within the tubules
* Increased numbers of casts in urine = cylindruria
114
List the different types of casts.
– Hyaline casts
* >____ hyaline casts/10x objective is significant
– Cellular casts --> can be composed of ________ cells, _____, and/or ____
– ________ casts
– ______ casts --> indicate chronicity
– Hyaline casts
* >2 hyaline casts/10x objective is significant
– Cellular casts è can be composed of epithelial cells, RBCs, and/or WBCs
– Granular casts
– Waxy casts è indicate chronicity
115
116
Fat droplets
* Commonly seen (especially in ______ urine) and usually __________
* Result from degeneration of _________ cells
lining the urinary tract
* Can be differentiated from RBCs and
WBCs by being in a different _____ of
focus
– _________ in size but more uniformly ______
than cells
Fat droplets
* Commonly seen (especially in feline urine) and usually insignificant
* Result from degeneration of epithelial cells
lining the urinary tract
* Can be differentiated from RBCs and
WBCs by being in a different plane of
focus
– Variable in size but more uniformly round
than cells
117
Fat droplets
118
Mucus
* Commonly seen in ________ urine
* Can resemble _________ casts
– Mucus is more ________ shaped with _______ ends
Mucus
* Commonly seen in equine urine
* Can resemble hyaline casts
– Mucus is more irregularly shaped with tapered ends
119
Mucus
120
Contaminant fibers
121
Contaminant fibers
* Cotton, plant, and paper fibers
* Can mimic parasite larvae or urinary casts
122
Environmental fungi and pollen
