ALL the renal/urinalysis Flashcards
1
Q
Renal disease
A
morphologic or functional lesions of any size, distribution, or etiology involving one or both kiendys
- +/- accompanied by renal failure
- tells nothing about function
2
Q
Renal failure
A
accumulation of nitrogenous wastes & alteration in water/electrolyte/acid-base status due to reduced functional renal mass
- may eventually lead to uremia
3
Q
Azotemia
A
an increase in NPN compounds in blood
- does NOT imply presence of clinical signs
4
Q
Uremia
A
azotemic renal failure with the presence of clinical signs
5
Q
Renal insufficiency
A
when loss of functional nephron mass is more than 66.6% but less than 75%
- animal is polyuric b/c can no longer concentrate urine, but not yet azotemic
6
Q
What is the first course of action when presented with an azotemic patient?
A
determine source of azotemia (pre-renal, renal, post-renal)
7
Q
When does pre-renal azotemia occur?
A
- reduced renal perfusion
- decreased delivery of blood to kidneys
- congestive heart failure
- decr. effective arterial blood volume
- IV voume loss or shift to ECF (hemorrhage, severe burns, pancreatitis, hypoadrenocorticism, shock)
- Extravascular fluid loss (vomiting, diarrhea)
- increased vascular capacity (sepsis)
- decreased delivery of blood to kidneys
- increased urea production/protein catabolism
- high protein diet
- GI bleed
- starvation
- infection
- azathioprine
- tetracyclines
- exogenous corticosteroids
- fever
- burns
8
Q
USG of dog/cats with pre-renal azotemia
A
CONCENTRATED
dog >1.030
cat>1.35
9
Q
What type of urine sediment is associated with pre-renal azotemia?
A
inactive
10
Q
Renal excretion of urea
A
- glomerular filtration
- tubular reabsorption
11
Q
How does tubular flow rate affect reabsorption?
A
slower tubular flow rates = greater reabsorption
12
Q
Differentials for decreased BUN
A
- liver failure, low protein diets (i.e. decreased production)
- diuresis (i.e. increased excretion…due to decreased tubular reabsorption)
13
Q
Give an example of a normal case of lower serum creatinine
A
puppies (don’t yet have a large muscle mass)
14
Q
How is creatinine excreted?
A
- glomerlular filtration (almost exclusively)
15
Q
What is a good indicator of GFR?
A
creatinine clearance
16
Q
What species might have minimal tubular secretion of creatinine?
A
dog
17
Q
When might you have false elevations of creatinine and why?
A
Diabetic ketoacidosis
- acetoacetate is a non-creatinine chromagen which contributes to serum creatinine
18
Q
When do creatinine/BUN levels change most: early in renal disease with a large decrease in GFR or late in renal disease with small decrease in GFR?
A
Later in renal disease with small decrease in GFR
19
Q
renal azotemia occurs with ____% of nephron loss
A
75% & greater
20
Q
When does post-renal azotemia occur?
A
- obstruction to urine outflow
- calculi
- stricture
- foreign body
- tumor
- urinary tract rupture
21
Q
What type of urine sediment is associated with post-renal azotemia?
A
active
22
Q
What form of azotemia is hyperkalemia possibly associated with?
A
post-renal
23
Q
USG associated with post-renal azotemia
A
USG can be variable-because the kideys are still functioning at first
24
Q
What are two diagnostic methods that might be used when post-renal azotemia is suspected?
A
- abdominal ultrasound-preferred over rads
- abdominal fluid creatinine - with ruptured bladder, fluid creatinine will be > serum creatinine
25
Once pre and post-renal causes of azotemia are eliminated, how is renal azotemia confirmed? What are two exceptions?
Azotemia + isosthenuria or minimally concentrated urine
Exceptions:
* cats (can concentrate late into renal disease)
* glomerular disease
26
clinical findings that support renal azotemia
* **glucosuria w/o hyperglycemia**
* **mod./severe proteinuria**
* **mod./severe cylindruria**
* alkalinuria with concurrent systemic acidosis
* non-regenerative anemia
27
How do kidneys in ARI vs. CKD differ on ultrasound?
ARI-normal to large kidneys
CKD-small, irregular kidneys
28
Which form of renal disease is likely to be associated with anemia?
CKD
29
List common causes of ARI
* ethylene glycol toxicity
* drugs (**aminoglycosides**)
* hypercalcemia
* hypokalemia (**cats**)
* volume depletion
* **sepsis**
* **pancreatitis**
* infectious causes
* **bacterial pylelonephtritis**
* **leptospirosis**
* multiple disorders (18%)
* unknown cause (22%)
30
Risk factors for ARI
* advanced age
* preexisting renal disease
* dehydration/reduced renal perfusion
* hypokalemia, hypercalcemia
* diuretics, nephrotoxic drugs
* liver disease-possibly
* any factor known to cause renal failure
31
What is a common cause of CKD in older cats?
pyelonephritis
32
Clinical signs of urine outflow obstruction
* dysuria
* hematuria
* paradoxical incontinence
* fluctuations in urine volume
* markedly distended bladder
* inability to pass urinary catheter
* renomegaly if hydronephrosis present
* uremic signs
33
Things to consider if azotemia is persistent after obstruction is relieved
1. not enough fluids are being given to make up for fluid losses due to post-obstructive diuresis
2. preexisting renal disease has led to renal failure
3. the obstruction was long-standing and caused renal failure
34
How can you evaluate for post-obstructive diuresis? Within what timeframe should this resolve?
* measuring urine volume every four hours
* should resolve in 48-72 hours
35
What species is more prone to post-obstruction diuresis?
cat
36
Clearance
the volume of a substance removed from the plasma per unit time
37
The clearance of substances such as Na, Cl, and Ca is _________ (greater or less) than GFR
less
(these are reabsorbed only-no tubular secretion)
38
Clearance of PAH is \_\_\_\_\_\_\_\_(greater/less) than GFR
greater
substance is secreted, but not reabsorbed
39
How is uric acid handled by the kidneys?
it is both secreted and reabsorbed
40
How is creatinine handled by the kidney?
filtered by glomerulus and not substantially reabsorbed or secreted
41
Most appropriate test for determinng reneal excretory function when non-azotemic renal failure (renal insufficiency) is suspected
exogenous creatinine clearance
42
What are the advantages of radioisotope studies?
* not time consuming
* don't require urine collection
43
Disadvantage of radioisotope studies
* must be performed at referral institution
44
Tests of glomerular function:
* endogenous creatinine clearance
* exogenous creatinine clearance
* radioisotope studies
* plasma clearance of iohexol
45
Easiest & most reliable method available for calculating GFR
plasma clearance of iohexol
46
Contraindications for water deprivation test
animal with renal failure or insufficiency
47
Tests of tubular function
* USG, urine osmolality
* fractional clearances of electrolytes
* ammonia challenge tests
* (water deprivation tests)-technically a test of renal tubular concentrating ability but don't us in animal with renal failure/insufficiency
48
Ammonia challenge tests are used for what?
* assessing urinary acidifying ability when evaluating renal tubular disorders, specifically renal tubular acidosis
49
What are two potential values of doing a renal biopsy in an animal with AKI?
1. establish etiologic dx
2. facilitate prognostication via evaluation of overall appearance of renal tissue and integrity of tubular basement membrane
50
What is the primary purpose of a renal biopsy when the animal has PLN?
determine whether or not to use immunosuppressive drugs
51
Contraindications to renal biopsy
* uncontrolled coagulopathy
* severe hydroephrosis
* large renal cysts
* perirenal abscess
* extensive peylonephritis
* solitary or extremely small kidney
* end-stage renal disease
* inexperienced operator
* incomplete patient immobilization
52
What region of the kidney is biopsied?
cortex
53
Why should the corticomedullary junction and medulla be avoided when performing a renal biopsy?
large renal vessels are present
54
Three methods for renal biopsy are:
1. percutaneous
2. laparoscopic
3. laparotomy
55
What are some advantages to using laparotomy to perform a renal biopsy?
* both kidneys can be visualized with the midline approach
* hemorrhage can be controlled
* can ensure adequate biopsy
56
Complications occur in \_\_\_% of dogs & cats undergoing renal biopsy
17
57
What is the most common complication that occurs from renal biopsy?
hemorrhage
58
How is severe hemorrhage defined?
PCV\<20%
59
What is the likely cause of hydronephrosis after a biopsy?
obstruction of the ureter with blood clots
60
Polydipsia definition
water consumption \>100 ml/kg/day
61
Polyuria definition
urine production greater than 50 ml/kg/day
62
Oliguria definition
production of less than 1.0 ml/kg/hour of urine
63
Hx/PE abnormalities suggestive of renal failure
* changes in urine volume
* GI abnormalities
* abnormal kidney size/contour/texture or pain on palpation of kidneys
* hematopoietic abnormalities
* skeletal abnormalities-"rubber jaw"
* cardiopulmonary & vascular abnormalities
* neurologic abnormalities
* non-specific signs
* anorexia
* chronic progressive weight loss
* lethargy
64
What size should the kidneys be?
* 2.5-3.5x the length of the second lumbar vertebral body in dogs
* 1.5x the length of the second lumbar vertebral body in the cat
65
Abnormal fluid retention might be related to \_\_\_\_\_
PLN
66
Common causes of CKD
* most often undetermined
* glomerulonephritis
* prior ARI episode
* pyelonephritis (often older cats)
* familial
67
Four therapeutic goals for renal failure
1. avoid stress
* if animal stops drinking-\>pre-renal azotemia
2. provide unlimited fresh water
3. avoid nephrotoxic agents
4. allow for adequate exercise
68
Risk factors for ARI
* advanced age
* pre-existing renal disease
* dehydration or other causes of decreased renal perfusion
* hypokalemia
* hypercalcemia
* concurrent use of diuretics or nephrotoxic drugs
* liver disease (MAYBE)
* presence of other factors known to cause renal injury
69
Causes of infectious ARI ("nephritis)
* bacterial pyelonephritis
* leptospirosis
* rickettsial diseases
* RMSF
* ehrlichiosis
* "lyme nephritis"
70
Phases of ARI
* induction (initiation)
* maintenance
* recovery
71
What is often given in cases of ethylene glycol ingestion?
4-MP (fomepizole)
72
What are some reasons the kidneys may be large instead of small, as is expected with CKD?
* renal neoplasia
* hydronephrosis
* compensatory hypertrophy of solitary surviving kidney
* renal cysts
* renal abscesses
* FIP
* renal amyloidosis
* membranous glomerulonephropathy--cats
73
ARI therapeutic goals
* prevent further damage
* remove inciting cause
* remove pre & post-renal factors
* production of diuresis
* sustain patient's life during recovery
74
Why is production of diuresis in ARI relevant?
polyuric patients have better prognosis
75
CKD therapeutic goals
* alleviate clinical signs
* reduce rate of progression
* eliminate obvious factors causing acute deterioration
* implement factors known to slow progression
* keep current knowledge base!
* work w/in owner comfort zone
76
FACTORS KNOWN TO SLOW PROGRESSION OF CKD IN DOGS & CATS
HAD2P
* manage **H**ypertension
* mange **A**nemia
* feed renal **D**iet
* manage renal **2**ndary hyperparathyroidism
* reduce magnitude of **P**roteinuria
77
Factors impacting morbidity of CKD
* UTI
* hypertension
* hypokalemia (primarily cats)
* ureteroliths(primarily cats)
* gastroenteritis
* dehydration
78
Staging CKD is based on \_\_\_\_\_
Substaging CKD is based on \_\_\_\_\_\_\_
Staging-CREATININE
Substage-PROTEINURIA, HYPERTENSION
79
When does uremia occur?
* severe AKI
* stage IV CKD
80
Restoration of euvolemia should occur within what timeframe?
6 hours
81
Signs of severe overhydration
* weight gain
* edema
* distended jugular veins
82
What is the first method you should try in a patient to try to remedy oliguria?
Fluid diuresis (not effective if already overhydrated)
83
What drug is synergistic with furosemide?
dopamine
84
When is chronic fluid therapy appropriate to initiate?
* Stage 4 CKD
* sometimes used in recovering ARI
85
How should alkalinization be approached in an ARI patient vs. CKD?
ARI
* sodium bicarb IV
CKD-stage 4
* sodium bicarb PO
* potassium citrate PO-often in cats for added potassium benefit
86
What parameters indicate alkalinization is appropriate?
pH\<7.20 or TCO2\<12
87
Is hyperkalemia more common in ARI or CKD?
ARI
88
When is hyperkalemia seen in CKD patients?
CKD patients on ACE inhibitors or those with oliguria/anuria
89
Appropriate treatment for hyperkalemia \>8mEq/L or if arrythmias are present
* sodium bicarbonate
* insulin & dextrose
* calcium gluconate
90
How can you prevent hypokalemia from occurring during forced diuresis?
add KCl to fluids
91
What are some consequences of hypokalemia to be aware of?
* renal vasoconstriction
* K+ depleted cells are more susceptible to necrosis
* downregulation of aquaporin-2 (inhibits ADH)
92
Renal diets improved MST by how much in dogs? cats?
dogs: 3x
cats: 2.4x
93
What is one drawback to renal diets?
caloric density contributes to obesity
94
What is the phosphate binder that is usually used when renal diets alone are not enough to control hyperphosphatemia?
aluminum hydroxide
95
How is anemia generally treated in ARI vs. CKD?
* ARI--\>Whole Blood Transfusion
* CKD--\>epoetin, darbepoetin
96
What are some ways GI distress can be managed?
* dietary protein restriction
* H2 blockers
* Cimetidine, Ranitidine, famotidine
* Proton pump inhibitors
* omeprazole, esomeprazole
* antimetics as needed in ARI or acute exacerbation of CKD
97
Uncotrolled hypertension ocular effects
* retinal, vitreal, or anterior chamber hemorrhage
* retinal detachment & atrophy
* retinal edema
* perivasculitis
* retinal vessel tortuosity
* glaucoma
98
How much can an ACE inhibitor be expected to lower blood pressure when used by itself?
15%
99
Enalapril and Benzapril are used for what?
ACE inhibitors used for treating hypertension
100
ACE inhibitors are used for managing hypertension but have what added benefit?
reduce proteinuria
101
In early stages of AKI, what parameters should be measured daily/several times a day?
* BUN/Creatinine daily
* PCV/TS several times a day
102
Paramenters to be monitored and how often with CKD
* PE, hx: 2-4x per year
* panel, PCV/TS, UA: 2-4x per year
* urine culture: 2x per year
* blood pressure: every visit
103
Uncontrolled hypertension effects on the heart
* left ventricular hypertrophy with secondary valvular insufficiency
104
Uncontrolled hypertension effects on kidney
* progressive renal decline of renal disease
105
Uncontrolled hypertension effects on brain
* cerebrovascular hemorrhage
* may manifest as head tilt
* depression
* seizures
106
Clinical signs of renal disease can vary depending on:
1. etiology of disease
2. severity of disease
3. duration of disease
4. rate of progression of primary dz process
107
Why are clinical signs often more severe in an animal with ARI than an animal with CKD that has the same level of renal dysfunction?
Animals with ARI have not had time to adapt to the physiologic changes asssociated with renal failure
108
What laboratory finding would suggest ethylene glycol toxicosis?
hippurate or CaOx crystals
109
What are some clinical signs that occur in CKD that may allow differentiation from ARI?
* long hx of weight loss & PU/PD
* poor BCS
* non-regenerative anemia
* small, irregular kidneys
* fibrous osteodystrophy
* gastric or other tissue mineralization
110
Renal diet characteristics
* mod. protein restriction
* phosphorous restriction
* sodium restriction
* Omega 3:omega 6 ratio enhanced
* high in water soluble vitamins
* increased caloric density
* increased fiber content
* added K+ in feline diets
111
What might happen if a diet is too restricted in protein?
* aggravate anemia, acidosis
* protein depletion & muscle wasting
* worsen renal hemodynamics
112
When is amlodipine indicated?
In hypertension cases that aren't responding enough to an ACE inhibitor alone
113
What UPC value is associated with more rapid progression of CKD in dogs? cats?
dogs: UPC\>1
cats: UPC\>0.4
114
Clinical signs of hypokalemia often develop when serum potassium is less than what value?
2.5 mEq/L
115
How does increased GFR affect protein passage through glomerulus?
increase
116
How does decreased renal plasma flow affect protein passage through the glomerulus?
increase
117
How does decreased GFR affect protein passage through the glomerulus?
decrease
118
How does increased renal plasma flow affect protein passage through the glomerulus?
decrease
119
What are the components of normal urine?
* albumin (40-60% of total urine protein)
* low molecular weight proteins-small amounts
* Peptide hormones (insulin, PTH, GH), enzymes (lysozyme), Ig fragments
* Tamm-Horsfall Protein
120
How much protein is found in normal dog urine?
5-10ug/dl
121
Post-renal proteinuria is associated with hemorrhage or inflammation of:
* ureter
* bladder
* urethra
* prostate
* prepuce
* vagina
122
3 subtypes of renal proteinuria
1. functional/physiologic
2. tubular
3. glomerular
123
What does a persistently elevated urine protein content indicate?
proteinuria associated with glomerular disease
124
Causes of glomerular proteinuria
* glomerulonephritis (membranoproliferative or proliferative)
* membranous glomerulonephropathy
* amyloidosis
* glomerulosclerosis-including focal segmental glomerulosclerosis
* minimal change disease
* hereditary nephritis
125
Causes of tubular proteinuria
* acute tubular necrosis
* Fanconi
* drug/toxin-induced proximal tubular damage
* aminoglycosides
* NSAIDs
* heavy metals
* ethylene glycol
* hypercalcemia
* hypokalemic nephropathy
* tubulointerstitial disease
126
50-90% of dogs with chronic renal failure have \_\_\_\_\_\_
glomerular disease
127
What is the most common cause of proteinuria?
post-renal
128
With tubular proteinuria, what is the expected USG?
isosthenuric-minimally concentrated range
129
What is the expected USG with glomerular proteinuria?
normally concentrated unless late in disease
130
Three most common causes of glomerular proteinuria
* amyloidosis
* glomerulonephritis
* focal segmental glomerulonephritis
131
The urine dipstick is what type of test?
qualitative
132
What protein is the urine dipstick most sensitive to?
albumin
133
What circumstances can yield false positives with a urine dipstick?
* highly alkaline urine (pH\>8-9)
* dipstick immersed for long periods of time
* urine is contaminated with quaternary ammonium compounds(e.g. cleaning agents)
134
Under what circumstances do false negatives occur with a urine dipstick?
* dilute urine
135
False positives may occur with what circumstances when using the bumintest?
* organic iodides(radiographic contrast dyes)
* large amounts of penicillins, sulfisoxazole, or thymol(urine preservative)
136
Highly alkaline or dilute urine may produce false _______ with the bumintest
negatives
137
When is a quantitative test indicated?
* when animal is hypoalbuminemic
* repeat positive screening tests and a normal urine sediment examination
* absence of pre & post-renal causes of proteinuria
138
What is the gold standard for measuring urine protein losses?
24 hour urine protein content
139
What test correlates well with the 24 hour urine protein content in both cats and dogs?
UPC
140
Normal UPC values in cat & dog
dog: \<0.5
cat: \<0.4
141
What are two diseases that are considered with especially high UPC ratios?
* glomerulonephritis
* amyloidosis
142
What should you do if you detect proteinuria in a dog or cat with mild to moderate pyuria?
reevaluate a urine sample after the cause of pyuria is eliminated
143
What test characterizes protein fractions in urine samples, thereby allowing for the determination of relative contribution of albumin and globulin to total urine protein content?
urine protein electrophoresis
144
The usefulness of urine protein electrophoresis is limited to what two situations?
1. detection of low molecular weight proteinuria associated with overload proteinuria
2. identification of albuminuria as the cause of hypoalbuminemia in animals with LUT hemorrhage or inflammation that is not responsive to therapy
145
What is the point-of-care RIA that is used to detect microalbuminemia?
E.R.D.-HealthScreen
146
Factors that lead you to suspect glomerular proteinuria
* hypoalbuminemia
* concurrent systemic infectious or inflammatory disease
* patient has renal azotemia but NOT isostheunuric (pre or post renal causes of azotemia have been excluded)
147
Factors that would lead you to suspect tubular disease
* normal serum albumin
* other abnormalities suggestive of tubular disease
* glucosuria w/o hyperglycemia
* isosthenuria
148
What is pathognomonic for glomerular disease?
Nephrotic syndrome
149
**Nephrotic syndrome**
* hypoproteinemia(hypoalbuminemia)
* proteinuria
* hypercholesterolemia
* edema
150
Three reasons why animals with glomerular disease are predisposed to thromboembolic disease
1. Loss of ATIII
2. hyperfibrinogenemia
3. enhanced platelet function
151
What types of casts are associated with degeneration and necrosis of tubular epithelial cell?
granular, waxy, fatty
152
What is the explanation given for the development of ascites and edema?
decreased oncotic pressure-\>decreased plasma volume-\>decreased CO-\>decreased renal blood flow-\>activation of renin-angiotensin system-\>increased aldosterone-\>renal salt and water conservation
153
What factors are serine prteases?
Factor II, IX, X, and XII
154
What form of glomerulonephritis do cats most often have?
membranous
155
What form of amyloidosis is reported in dogs and cats?
reactive(secondary)
156
Where is amyloid deposited in most dogs?
glomeruli
157
Where is amyloid primarily deposited in cats?
medulla
158
How does amyloidosis look on light microscopy?
homogenous eosinophilic material characterized by green birefringence when stained with Congo Red
159
What test might be beneficial annually in a breed predisposed to amyloidosis?
microalbuminemia screening
160
What are some causes of glomerulosclerosis?
* hypertension-induced
* diabetes mellitus (primarily people)
* secondary to another glomerular injury
* focal segmental glomerulosclerosis - primary glomerular disease recently demostrated in dogs
161
What is a specific goal of therapy for amyloidosis?
decrease deposition and increase mobilization of amyloid fibrils
162
What is a specific goal of therapy for glomerulonephritis?
decrease the deposition of circulating immune complexes & decrease resultant inflammation
163
Describe supportive care for proteinuric patients
1. **ACE-inhibitors**-indicated in all dogs and cats with renal proteinuria, even if they do not have systemic hypertension **(Enalapril, benzapril)**
2. **renal diets**
3. **diuretics** if edema & ascites are present
* **spironolactone** may be pref. to furosemide because it inhibits aldosterone(aldosterone may contribute to progressive renal damage)
4. dietary **salt restriction** for edema/ascites
5. **B vitamin supplemenation** to replace losses in polyuric patients
6. free access to water, limit stress, ample exercise
7. **Aspirin or clopidogrel** (plavix) in patients at-risk for thromboembolic dz
8. control hypertension if present
9. edematous & azotemic/uremic patients very difficult to manage; may need plasma transfusions or plasma expanders to increase plasma volume, thereby removing pre-renal factors and allowing effective diuresis
10. treat uremic signs
164
What is a contraindicated medication to give to animals with amyloidosis?
corticosteroids
165
What is the usefulness of colchicine?
should be instituted before onset of proteinuria or renal failure in Shar peis to be most effective
166
What are some early signs of Shar peis at risk for amyloidosis?
* recurrent fevers
* swollen, painful hocks
167
What parameters should be monitored to assess for progression of disease or response to therapy in proteinuric animals?
* serum creatinine & albumin
* UPC
168
What are two reasons for a decrease in proteinuria?
1. improving glomerular function
2. decreasing GFR with overall worsening of the disease state (detected by increasing serum creatinine)
169
What should be performed if proteinuria is detected and pre and post-glomerular causes can be excluded?
UPC
170
What are the 'NINs'?
* non-infectious inflammatory diseases
* infectious diseases
* neoplastic diseases
171
Under what circumstances should you consider a renal biopsy?
* animal has persistent proteinuria and
* no identifiable underlying disease
* proteinuria has persisted after treatment of underlying disease
* treatment must be an option
172
How should a renal biopsy be evaluated?
* light microscopy
* electron microscopy
* IFA
173
"advanced azotemia" refers to serum creatinine above what?
serum creatinine \> 4.0
174
What breeds are associated with primary renal glucosuria?
* norwegian elkhouds
* beagles
175
What breeds are associated with congenital renal tubular dysfunction?
* Basenji
* Norwegian elkhound
* Schnauzer
* Shetland sheepdog
176
Glucose threshold in dog? cat?
dog: 180-220 mg/dl
cat: 200-300 mg/dl
177
What three categories are glucosuria classified into?
1. glucosuria assoc. w/ hyperglycemia
2. primary renal glucosuria
3. renal tubular dysfunction
178
What are the criteria for a diagnosis of primary renal glucosuria?
* glucose present in all urine samples
* fasting blood glucose
* normal glucose tolerance curve
* no progression to DM
* familial hx of renal glucosuria (norwegian elkhounds, beagles)
179
List four differentials for glucosuria associated with hyperglycemia
1. diabetes mellitus
2. acute pancreatic necrosis
3. parenteral dextrose therapy
4. exogenous or endogenous epinephrine(primarily cats)
180
What are possible clinical signs with primary renal glucosuria?
* polyuric/polydipsic
* may have bacterial cystitis
* usually have normal renal function
* often ASYMPTOMATIC
181
How should dogs with primary renal glucosuria be treated?
no specific treatment needed, except treatment of recurrent UTIs
182
Prognosis for primary renal glucosuria
good
183
This disease is associated with multiple transport abnormalities
congenital renal tubular dysfunction (Fanconi syndrome)
184
How does congenital renal tubular dysfunction progress?
* initially, only abnormal urinalysis
* slowly progresses to CRF
185
Long term prognosis for congenital renal tubular dysfunction
* poor; expect chronic debilitation
186
How is congenital renal tubular dysfunction treated?
manage the signs of CRF as they arise
187
Aminoglycosides harm what part of the nephron?
proximal tubule
188
Some causes of acquired tubular dysfunction?
* aminoglycosides
* pyelonephritis
* chronic hypocalcemia
* copper storage disease
* lead toxicity
* **jerky dog treats**(chicken, chicken/sweet potato)
* other tubular toxins
189
When glucosuria is associated with euglycemia, what is the most likely origin?
renal tubular
190
When glucosuria is of renal origin, what are the differentials?
* primary renal glucosuria
* renal tubular dysfunction
191
Where in the kidney is the problem if isosthenuric?
global or problem with loop of henle
192
Hyposthenuria indicates a problem with what?
ADH mechanism
193
What is the serum osmolality with primary polydipsia?
possibly low
194
What are the rule-outs for primary polydipsia?
* hepatic failure
* congenital PSS
* hypothalamic lesion
* psychogenic
195
What is a normal serum osmolality?
290-310 mOsm/kg
196
What are some causes of CDI?
anything that damages neurohypophyseal system
* idiopathic
* trauma
* neoplasia
* pituitary malformation
* inflammation
197
What is the mechanism of nephrogenic diabetes insipidus?
lack of response of distal tubule & collecting duct to ADH
198
What is the expected USH for nephrogenic diabetes insipidus?
hyposthenuric
199
What is the expected USG with osmotic diuresis?
isosthenuria-minimally concentrated
200
How does hyperadrenocorticism interfere with concentrating ability?
glucocorticoids:
* inhibit ADH release
* promote renal resistance to ADH
201
How does hypoadrenocorticism interfere with concentrating ability?
sodium loss-medullary washout
202
How does pyelonephritis interfere with concentrating ability?
1. endotoxins compete with ADH binding sites
2. inflammation & infection in renal pelvis destroys countercurrent mechanism
203
How does hepatic failure contribute to reduced concentrating ability?
* decreased urea production-medullary washout
* psychogenic polydipsia
204
How does hypercalcemia reduce concentrating ability?
may interfere with or damage ADH receptors and interfere with renal tubular handling of sodium
205
How doe hypokalemia reduce concentrating ability?
decreased responsiveness of the terminal nephron to ADH
206
How does acromegaly reduce concentrating ability?
development of DM, osmotic diuresis (per clin path notes)
207
What species is most prone to post-obstructive diuresis?
cats
208
List some causes of osmotic diuresis
* DM
* primary renal glucosuria
* renal insufficiency/failure
* post-obstructive diuresis
209
Iatrogenic polyuria can be caused by \_\_\_\_\_\_\_\_
1. diuretics
2. glucocorticoids
* dogs mostly
* if cats develop PU from glucocorticoids, they are probably diabetic
3. phenobarbital, other anticonvulsants
210
What is the use for plasma osmolality when evaluating a PU/PD case?
rule out primary polydipsia-may have _low_ serum osmolality
rule out primary polyuria-may have _increased_ serum osmolality
211
Contraindications for a water deprivation test
known renal failure or dehydration
212
Normal dog response to water dehydration test
* dehydrate slowly
* achieve max USG of 1.050-1.075 in 40 hours(some require 78 hours)
* no further increase after vasopressin adminstration
213
How do dogs with CDI respond to water deprivation test?
* rapidly dehydrate (within 3-6 hours)
* do not produce concentrated urine even in face of severe dehyration
* vasopressin will cause a 50-800% increase in urine concentration
214
How do dogs with NDI respond to water deprivation test?
* cannot concentrate urine with severe dehydration
* **do not respond to vasopressin**
215
What is the diagnostic approach to PU/PD?
1. complete Hx/PE
2. repeat USGs
3. quantify water intake or urine output
4. CBC, biochemical panel, UA
5. specific tests (e.g. adrenal, renal function tests)
6. Plasma olsmolality test
7. gradual water deprivation test if indicated
8. DDAVP-as alternative to water deprivation test or when water deprivation test has not aided in establishing diagnosis.
216
What response to the DDAVP test is suggestive of CDI or partial NDI?
decrease in water consumption \>50%
217
How is psychogenic polydipsia treated?
reduce water intake gradually, over several weeks, to normal daily volume
218
How do dogs with hyperadrenocorticism or psychogenic polydipsia respond to water deprivation test?
* concentrate into range of minimal concentration or sometimes over 1.030
* 10-50% increase in urine concentration in response to vasopressin
219
How can CDI be managed?
* DDAVP = intranasal preparation into conjunctival sac q12 or 24 hours or oral formulation(may not be effective in some dogs)
220
How can nephrogenic diabetes insipidus be managed?
* eliminate underlying cause whenever possible
* thiazide diuretics (Chlorothiazide)
* used with caution
221
What is a consideration when using serum osmolality to differentiate primary polyuria from primary polydipsia?
this is only effective if the animal has had free access to water leading up to the test
222
What terms are related to problems in the lower urinary tract?
* dysuria
* stranguria
* pollakiuria
223
Reasons for inappropriate urination
* behavioral
* secondary to LUTD
224
What terms are associated with disease anywhere in the urinary tract?
* hematuria
* pyuria
225
Hematuria/pyuria differentials
* **infection**
* **calculi**
* neoplasia
* idiopathic (cats; RBC\>WBC)
* coagulopathy (hematuria only)
* trauma
* ischemia
226
Most comon differential for feline LUTD w/o obstruction in a young cat
Idiopathic cystitis
227
Most common differential for feline LUTD w/o obstruction in an older cat
bacterial UTI
228
Differentials for Feline LUTD w/o obstruction
* bacterial UTI
* cystolithiasis
* idiopathic cystitis
* bladder neoplasia (rare in cats)
229
Differentials for FLUTD with obstruction
* Urethral plug
* Uroliths
* Unidentified
* neoplasia-rare
* stricture
230
What is the most likely cause of FLUTD w/ obstruction if NOT an older cat?
urethral plugs
231
Two types of functional obstruction
* spasm
* reflex dyssynergia
232
Most comon mineral found in urethral plugs
struvite
233
What is an example of an extraluminal obstruction?
neoplasia in pelvic canal pressing on urethra
234
What are the two most common differentials for canine LUTD without obstruction?
What are other differentials?
* bacterial cystitis
* cystoliths
other:
* prostatic disease
* bladder neoplasia
* bladder trauma
235
What are the two most common differentials for canine LUTD with obstruction?
others?
* uroliths
* neoplasia
others include foreign body(catheter?), stricture, neoplasia, trauma, reflex dyssynergia, muscle spasm
236
**What are the normal host defenses to the urinary tract?** give an example of how they are often broken
* **normal micturition**
* ****incontinence
* **anatomic structures**
* hooded vulva
* **mucosal defense barriers**
* E. coli, urolith damage to mucosal surface
* **antimicrobial properties of urine**
* USG altered
* **systemic immunocompetence**
* ****Cushing's or exogenous steroid admin.
237
What infectious agent is most associated with chonic or recurrent UTI?
Pseudomonas
238
What is the most common cause of bacterial UTI?
E. coli
239
What is a cause of fungal UTIs?
Candida spp.
240
What other finding is common in animals found to have a UTI caused by Candida?
Immunosupppression; e.g. hyperadrenocorticism
241
What is a typical history of animals with lower urinary tract infection?
* pollakiuria
* urge incontinence
* stranguria
* dysuria
* hematuria
242
Expected UA findings in an animal with LUTD
* bacteriuria
* hematuria
* pyuria
* increased epithelial cells
* alkalinuria
* proteinuria
243
When might urinalysis findings be inconsistent with what you might expect for a LUTD?
* immunosuppressed animals (DM, hyperadrenocorticism)
* dilute urine can mask findings
* bacteria not always detectable
244
How should a urine sample for culture be collected?
cystocentesis
245
How many CFU/ml are consistent with UTI if cysto sample was used?
\>1000 CFU/ml
246
How many CFU/ml are consistent with a UTI if a catheterized sample was used?
\>10,000 CFU/ml
247
What kind of signs are NOT found in association with lower UTI?
systemic signs of infection
248
What are some components of a history consistent with pyelonephritis/prostatitis?
* lethargy
* depression
* anorexia
* PU/PD
249
Biochemical changes of sepsis
* hypoglycemia
* increased alk phos
* increased bilirubin
250
If you are lucky enough to find WBC casts in urine, you can make a diagnosis of \_\_\_\_\_\_\_\_\_
pyelonephritis
251
What may be needed to detect chronic pyelonephritis or prostatitis?
Ultrasound; there are almost always ultrasonographic abnormalities but not always other expected abnormalities (fever, pain, CBC, UA-although usually UA is abnormal too)
252
What findings are associated with pyelonephritis on excretory urogram?
* renal pelvic dilatation or asymmetric filling of diverticula
253
How to handle initial episode of UTI
* history
* PE
* UA
* urine culture, ideally
* antibiotic treatment; ideally based on culture results, or empirical
* often clavamox
* 10-14 days
254
How to handle persistent or recurrent UTI
* History
* PE
* UA
* **need urine C/S**
* +/- CBC, biochem
* evaluate **prostate in males**
* +/- radiography/ultrasound/contrast studies
* antibiotic theraby based on C/S
* **30-45 days**
* repeat culture 5-10 days after stopping therapy
* negative--\>repeat 2x at 2-4 wk intervals
* positive--\>treat another 30-45d based on C/S
255
How should you address a suspect pyelonephritis/prostatitis?
* History
* PE
* Urine C/S
* (prostatitis-ejaculate or prostatic wash for C/S)
* CBC, biochem
* ID & correct predisposing factors
* Antibiotic treatment similar to recurrent UTI
* 30-45 days
* repeat urine cultures-continue until 3 negative urine cultutes obtained over 3 month period
* (prostatitis-castration)
256
How is "recurrent" defined when talking about UTIs?
\>2 UTIs in 6 months
or
\>3 UTIs in a year
257
**What are the urinary tract's normal host defenses?**
* **micturition**
* **anatomic structure**
* **mucosal defense barriers**
* **antimicrobial properties of urine**
* **immunocompetence**
258
Ancillary therapeutic aids for treating UTIs
* permit complete & frequent voiding
* avoid periods of prolonged urine retention (\>4-5 hours)
* urinary antiseptics
* urinary bladder irrigation-little value
* analgesics, antispasmodics
* cranbery extract-useful if infection known to be E. coli if high enough dose
259
What is a very good indicator of prostatic disease?
Blood dripping from urethra independent of urination
260
What clinical signs characterize prostatic disease?
* hematuria
* **blood dripping from urethra independent of urination**
* tenesmus
* signs compatible with UTI
261
If treating prostatic disease with castration, how soon should bleeding resolve and prostate size decrease if it was BPH?
* bleeding stops in 4 weeks
* prostate decrease by 70% in 3-4 months
262
Most common prostatic tumor types
* adenocarcinoma
* TCC
263
What is the most likely diagnosis if the prostate is enlarged in a castrated male dog?
prostatic neoplasia
264
What is the mean age of dogs affected with prostatic neoplasia?
10 years
265
What does cytology look like if BPH?
mild inflammation, hemorrhage
266
How does the prostate feel with prostatic neoplasia?
firm, irregular
267
\_\_\_\_% of bladder & urethral tumors in dogs are malignant
95%
268
Most bladder/urethral tumors of dogs are what type?
TCC
269
What less common tumor types can occur in lower urinary tract of dogs?
* SCC
* adenocarcinoma
* undifferentiated carcinoma
* mesenchymal
* benign fibroma, leiomyoma
270
What % of dogs diagnosed with LUT TCC have metastasis at diagnosis?
50%
271
Risk factors for lower urinary tract neoplasia
* obesity
* female
* exposure to herbicide-treated lawns
* Breed
* **scottish terriers-**18x risk \> mixed breed
* shetland sheepdog-4x increase
* beagle-4x increase
* west highland white terrier-3x increase
* wire-haired fox terrier-3x increase
* airedale terrier
272
What NSAID is usually used for lower UT neoplasia?
piroxicam
273
What chemo drug is usually used for lower urinary tract neoplasia?
mitoxantrone
274
What sex of cats has higher incidence of bladder tumors?
male
275
What types of bladder tumors are most common in cats?
* carcinomas (~56%)
* benign mesenchymal tumors (19%)
* malignant mesenchymal tumors (19%)
* lymphoma (7%)
276
What type of tumor are most urethral tumors in cats?
TCC
277
Radiographic findings of FIC
* focal or diffuse bladder wall thickening
* irregular mucosa
* vesicoureteral reflux
* contrast cystography normmal in 80% of cats
278
What is the role of diet in the management of FIC?
* target mildly acidic urine, dilute urine with few crystals
* added water
279
What are the effects of added water in dietary management of FIC?
* decreases concentration of noxious substances
* decreases bladder contact time with urine
* increases removal of excess crystals
* decreases palatability for some cats
280
Components of MEMO
* limit stress
* limit resource competition
* free access to water
* places to hide
* placees to sun
* opportunities to express natural behavior (climbing, etc.)
281
**What is a stepwise approach to treating feline interstitial cystitis?**
1. **treat immediate signs**
* ****pain control, fluids, diet changes
2. **MEMO**
3. **Feliway & other stress reducers**
4. **psychotropic drugs**
* **amitriptyline,** others
282
Clinical signs of urethral obstructions
* stranguria
* urine in unusual places
* hematuria
* no urine if severe
* licking penis
* uremic signs
* PE: distended, tense bladder
283
What is phenoxybenzamine and what is it used for?
* alpha-adrenergic antagonist-decreases smooth muscle urethral tone
284
Consequence of urethral obstruction
bladder atony - over-distention and loss of tight junctions of the detrusor muscle cells
285
Important biochemical changes associated with urethral obstruction
* acidemia
* hyperkalemia
* uremia
286
Appropriate treatment for an obstructed, azotemic & uremic patient
relief of obstruction, fluids needed for survival
287
**Struvite** (triple phosphate)
288
**Calcium Oxalate Monohydrate**
289
**Calcium Oxalate Dihydrate**
290
**Ammonium biurate**
291
**Uric acid**
292
**Calcium carbonate**
293
**Cystine**
294
**Cholesterol**
295
Most common urolith types in dogs and cats
struvite & calcium oxalate
296
What urolith type tends to form in alkaline urine?
struvite
297
What urolith type is associated with hepatic disease?
urate
298
What urolith type has a high incidence in dalmations?
urate
299
What urolith type has a high incidence in Dachshunds?
cystine
300
What urolith type has a high incidence in German Shepherds?
silicate
301
What urolith type tends to form in acidic urine?
cystine
302
What urolith type has the highest radiographic density?
CaOx
303
Decreased tubular absorption can promote the formation of what stone types?
* cystine
* urate
* calcium
304
most \_\_\_\_liths are not associated with any clinical signs
nephroliths, ureteroliths
305
What is by far the most common location of uroliths in dogs?
bladder
306
Most common site of urethroliths in a dog
just caudal to os penis
307
Uroliths that conform to the shape of the surrounding tissues are probably \_\_\_\_\_\_
struvite
308
Name two urease-producing bacteria
1. Staphylococcus
2. Proteus
309
What is the difference in struvite stone formation in cats vs. dogs?
Dogs: form in infected urine
Cats: form in sterile urine
310
How do you treat struvite uroliths in dogs?
* treat UTI based on C/S
* dissolution
* diet-acidify urine, restricted in phos.
* removal
* sx
* voiding urohydropropulsion if stones small
311
Prevention of struvite uroliths in dog
* evaluate for cause of chronic UTI
* monitor for UTI recurrence
* urine dipsticks at home; culture if any episode of hematuria or 3 days or more of urine pH \> 8
312
Treatment of struvite uroliths in cats
* diet that produces acidic urine, restricted in phos. & mg, diuresis
* removal
* sx
* voiding urohydropropulsion if small stones
313
Prevention of struvite uroliths in a cat
* encourage water consumption; feed canned diet
* maintenance diet restricted in Mg & Phos. that promotes acidic urine
314
Nephroliths are commonly what stone type?
calcium oxalate
315
Risk factors for developing calcium oxalate stones
* increased calcium absorption from gut (dogs)
* decreased tubular reabsorption of calcium
* secondary to hypercalcemia
* decreased concentrations of CaOx inhibitors
(Glycosaminoglycans, Tamm-Horsfall protein, Osteopontine, Citrate)
* increased oxalate ingestion(veg. grass)
* dry diets
* vitamin C, D supplements
* water restriction, urination restriction
* furosemide
* glucocorticoids
316
What breeds of cats may have a lower risk of CaOx stone formation?
* Birman
* mixed breed
* abyssinian
* siamese
317
Can CaOx stones be dissolved?
NO
318
What stone type has a high incidence in English Bulldogs?
Urate
319
Allopurinol can potentially lead to the formation of what type of stones?
xanthine
320
Treatment of urate stones
* dissolution: diet promotes alkaluria, diuresis, & restricted in protein
* allopurinol therapy
* removal
* sx
* voiding urohydropropulsion if stones are small
321
What stones are shaped like jacks?
silicate
322
What are some dietary sources of silicates?
corn gluten, soybean hulls, other plant protein
323
Therapy for silicate uroliths
surgical removal
324
What is the primary cause of cystine uroliths?
Cystinuria-inborn error of metabolism where there is defective renal tubualr absorption of cystine
325
Treatment of cystine uroliths
* dissolution: diet that promotes alkaline urine, diuresis, and restricted in protein
* 2-MPG (Thiola)
* removal
* sx
* voiding urohydropropulsin if small stones
326
Parasympathetic innervation to bladder
* pelvic nerve
327
Somatic innervation to bladder
pudendal nerve
328
Sympathetic innervation to bladder
hypogastric nerve
329
What type of receptors are predominately responsible for internal urethral sphincter function?
alpha-adrenergic
330
During voiding, what nerve inputs are inhibited?
* sympathetic input to internal sphincter
* somatic input to external sphincter
331
During the voiding phase, what is the role of parasympthetic activity?
stimulate detrusor contraction
332
Three reasons for problems with urine storage
1. USMI
2. detrusor hyperreflexia/instability
3. ectopic ureters
333
Causes for problems with bladder emptying
1. decreased detrusor muscle contractility
* LMN, UMN
2. increased urethral resistance
* outflow obstruction w/ paradoxical incontinence
* reflex dyssynergia
334
Where the lesion if you have UMN bladder?
above S1
335
What are the clinical findings associated with UMN bladder?
* unable to void-greatly distended bladder
* difficult/impossible to express
336
How should you treat UMN bladder? give specific drugs used
* relax internal urethral sphincter
* phenoxybenzamine
* prazocin
* relax external urethral sphincter
* diazepam
* may need to catheterize initially
* prevent urine scalding with petroleum jelly
337
Where is the lesion located with LMN bladder?
sacral cord or pelvic nerve
338
Clinical findings associated with lower motor neuron bladder
* urinary incontinence
* urinary bladder easily epressed
* absent or diminished perineal reflexes
339
What happens to urinary bladder/sphincter with LMN bladder?
atony
340
Treatment of LMN bladder
* intermittent bladder expression, catheterization
* bethanecol to cause detrusor contraction if urethra is patent
* prevent urine scalding with petroleum jelly
341
What is reflex dyssynergia?
incoordination between detrusor contraction and urethral relaxation
342
Reflex dyssynergia is associated with what three things?
* prostatic dz
* UMN lesions
* increased sympathetic activity
343
What causes detrusor areflexia?
damage to tight junctions from prolonged overdistension of bladder
344
What is the most comon cause of detrusor areflexia?
urethral obstruction
345
What drug is useful for detrusor contraction?
bethanecol
346
Breeds with higher incidences of ectopic ureters
* Siberian Huskies
* Miniature & Toy Poodles
* Labrador Retrievers
* Fox Terriers
* West Highland White Terriers
* Collies
* Welsh Corgis
347
What other abnormalities are often associated with ectopic ureters?
* renal dysplasia
* hypoplastic bladder
* vestibular vault abnormalities
* severe hydronephrosis
* pyelonephritis
348
Gold standard for dianosis of ectopic ureters
cystourethroscopy, vaginoscopy
349
If using contrast for diagnosing ectopic ureters, what method is best?
retrograde urethrogram
350
What are factors that can complicate USMI?
* obesity
* pelvic bladder
351
What disorder is primarily characterized by incontinence when the animal is in a lateral position?
USMI
352
USMI stand for \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
Urethral Sphincter Mechanism Incompetence
353
What is the most common cause of urge incontinence in dogs?
bacterial UTI
354
What is the most common cause of urge incontinence in cats?
sterile inflammation of LUT
355
Ectopic ureters are more commonly diagnosed in what sex?
female (20x)
356
Reflex dyssynergia is more common in what sex?
male
357
What disorder is most likely if incontinence occurs when animal is lateral?
USMI
358
How is estrogen synergistic with phenylpropanolamine?
Estrogen may increase the # of alpha receptors
359
Differentials for continuous incontinence
* ectopic ureters
* severe USMI (male)
360
Differentials if incontinence is intermittent at rest
* USMI
* occassionally ectopic ureter
361
Differentials if incontinence is intermittent while walking
* detrusor instability
* vestibular, vulvar, or vaginal anatomic abnormality
362
Differentials if normal stream but interrupted
* reflex dyssynergia
363
What is indicated in all animals with abnormal micturition?
Urine Cultue
364
What imaging studies are used in the case of neurogenic incontinence?
* MRI
* CT scan
* Myelography
* Epidurogram
365
Endoscopy is the best way to:
1. dx ectopic ureters
2. provide initial treatment of ectopic ureters
3. assess vagina & urethra
366
Drugs for detrusor relaxation
* Propantheline
* Oxybutynin
367
Indications for Bethanecol
* detrusor areflexia
* LMN bladder
368
Most common cause of incontinence in female dogs
USMI
369
age of cats at risk for CaOx stone formation
7-10 years
370
Breeds of dogs at risk for CaOx stones
* Miniature or Standard Schnauzer
* Bichon Frise
* Lhasa Apso
* ShihTzu
* Miniature Poodle
* Yorkshire Terrier
371
Why do urate stones form in cats?
unknown
372
Why are Dalmations predisposed to urate stone formation?
* decreased hepatic uric acid transport
* decreased proximal tubular uric acid reabsorption
373
How do you select an appropriate phosphate binder?
Use aluminum containing products or Renalgel® if serum phosphate is \> 7 mg/dl. Once
374
What is the most effective calcium-based phosphate binder?
calcium acetate
