MAIKO CKD Flashcards
EXAM
Azotemia
- definition
- 3 origins
- ↑ urea nitrogen, creatinine, other non proteinaceous
nitrogenous waste - 3 origins:
- Pre-renal (dehydration)
- Renal azotemia (renal lesion)
- Post-renal (obstruction)
Uremic syndrome
- what is it? clinical signs?
- Increased urea and other protein metabolism products
- Clinical signs (Gastro-intestinal, acidosis, pneumonitis, osteodystrophy, encephalopathy)
urinalysis and USG interpretation
- renal vs pre-renal azotemia
If Azotemia and USG low> renal azotemia
If high> pre-renal
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Normal USG in cats: 1,035-1,060
uremic vs azotemic
uremic means there are clinical signs for sure
International Renal Interest Society- IRIS Stages CKD
what are the stages?
Stage 1: no azotemia
Stage 2: mild azotemia
Stage 3 moderate azotemia
Stage 4: severe
Prevalence of Kidney Disease
1 in 43 cats
1 in 285 dogs
Chronic kidney disease pathogenesis
- injured kidney
> decreased in number and function of nephrons
> compensation by increasing size of remaining nephrons
> if 2/3 of renal mass is lost due to damage > lower USG, kidney insufficiency
> if 3/4 lost > azotemia, kidney failure
> uremia
CKD etiology, chronic vs acute
- Sustained functionnal +/- structural damage over >2-3 months or multiple AKI events
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Decline in renal function - Ischemic or toxic insult
- Leptospirosis
- Cellular injury, swelling, death
<><> - Reversible → Acute
- Irreversible → Chronic
> Loss of 3/4 renal mass
Causes of Chronic Kidney Failure
We wont know in most cases
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* Sequel to acute renal failure
* Urinary outflow obstruction
* Neoplasia (“big kidney” CRF, mayoccur w/o CRF)
* Inflammatory or infectious causes (Pyelonephritis,leptospirosis)
* Immunologic disorders (Glomerular diseases, lupus erythematous, vasculitis-FIP)
* Nephrotoxicants
* Renalischemia
* Nephrolithiasis – cause and effect ?
* Inherited/congenitaljuvenilerenalfailure(polycystickidneys)
* Idiopathic
Most Common reasons for CKD
- Sequel to acute renal failure
- Urinary outflow obstruction
- Nephrotoxicants
- Nephrolithiasis – cause and effect?
- Idiopathic
Physical Examination for CKD findings
- Dehydration
- Pallor
- Poor body condition score
- +/- Oral ulcers
- +/- small irregular kidneys
- Assess muscle condition score!
Risk Factors for CKD for Cats
- Poor body condition
- Periodontal disease
- Cystitis
- Being male neutered vs female spayed
- Anesthesia
- Documented dehydration in the preceding year
How do you diagnose Kidney Disease?
-
Essential: Creat/Urea and USG
<><> - History (+/- clinical signs)
- Persistent azotemia
- Inadequate urine concentrating ability
- +/- non regenerative anemia
- +/- abnormal sediment
Biochemistry Profile
CKF lab results, and reasons
- Azotemia (↑ urea and creatinine)
- ↑ phosphorus > ↓ phophorus excretion
- ↑ total calcium > Complexed calcium
- Metabolic acidosis > ↓ ability to excrete hydrogen ions
> Common complication of CRF in cats (60-80%)
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Low USG > Inappropriate
> Lost ability of concentrating urine
creatinine for CKD - use of this measure, what influences it, when increased
Influenced by muscle mass
* Increased in heavily muscled dogs (Greyhound)
* Decreased in dogs and cats with muscle loss
* Underestimation of azotemia in lean animals
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Impacted by food
* Create level can ↑ by 20% after eating cooked meat
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* ↑ when ≥75% reduction of renal mass
how to interpret creatinine
- muscle mass considerations
- when to measure
- when can use as a sign of CKD
- Not reliable in very thin animals (overestimate
kidney dysfunction) - Ideally measurement in fasted animals
- Late marker of kidney dysfunction
CREATININE
conventional markers of kidney function based on
Size of Dog- Reference Range (RR)
larger: 1/3 upper end of RR
mid size: 1/3 middle of RR
small: 1/3 lower end of RR
creatinine - how do levels change based on GFR in early vs advanced renal failure?
X - blood creatinine
Y - GFR
> graph starts with steep negative slope, becomes shallower over time
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- early renal disease - large changes in GFR have very little impact on blood creatinine
- advanced renal disease - small changes in GFR correspond to large changes in blood creatinine
> ie. we will see large changes in blood creatinine even when GFR changes a little bit in advanced renal disease
creatine reference ranges - are they the same for everyone?
Not really
- Each Dog has its own “normal” Creat
SDMA - what is it? what does it correlate with? values?
New Renal Biomaker
* Product of intranuclear protein metabolism
* Correlated with GFR strongly
* Correlated with creatinine and inulin clearance
* Cut off <14ug/dL IN ADULTS!
> higher for puppies
SDMA
- effect of body mass
- sensitivity vs sCr
- correlation to renal function
- possible issues? when its ok to use
- Not affected by lean body mass
- More sensitive marker for kidney disease than sCr in dogs and cats
- Persistent increases in SDMA >14ug/dL suggestive of reduced kidney function
- But specificity??
- Use it on lean animals
IRIS Classification staging - when should we stage an animal?
- Stage IRIS when animal stable (not in AKI)
- Wait for creatinine plateau before staging
Urinalysis for CKD - what might we see?
- Impaired urine dilution and concentration
- +/- proteinuria and hematuria
- Sediment
> Casts (tubular lesions)
> Bacteria
> Cylindruria
Anemia of CKD
- characterize
- how common
- reasons
- Nornomocytic, normochromic, non regenerative
- 30-65% of cats with CKF
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Reasons - ↓ erythropoietin production
- ↓ RBC survival
- GI tract blood loss
- Uremic toxins ↓ erythropoiesis
- Poor nutrition
- Acidosis
- Iatrogenic
- Infection
- Medication (ACEI and aluminium hydroxide)
Options to Treat Anemia of CKD?
- Address GI hemorrhage
- Blood transfusion (if tachycardia, weakness)
- AVOID Anabolic steroid (stanozolol)
> Benefits questionable
> Risk for hepatotoxicity in cats - Administration of erythrocyte-stimulating agents (ESAs)
Darbepoetin for anemia in CKD - when should we consider it? outcomes?
adverse effects?
- Consider once PCV < 20% (historic)
- Consider once PCV < 25% (IRIS group)
- Estimated success 60-65%
> anecdotally higher - Target PCV 28-30%
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Adverse Effects - Polycythemia
- Hypertension
<><> - Fever
- Seizure
- Arthralgia
- Iron deficiency
- Pure red cell aplasia
darbapoietin
- monitoring
- expected response time
- Recheck weekly until target reached
> PCV
> Blood pressure (most common side effect hypertension) - Median response is 3 weeks
> then can decrease injections (from weekly to every 2 weeks)
> Recheck every 2 weeks until stable
