Chronic and Acute Kidney Dz Flashcards
Chronic kidney dz
Persists of >3m
Creat >1.5 and BUN >33
USG: 1.008 -1.030 (inappropriate, not actively diluting or concentrating urine)
Non-azotemic kidney dz
Proteinuric (glo and tubular)
Structural (dysphagia, agenesis and vascular)
Pathophysiologic (degenerative, anomaly, metabolic, neoplasia, infection/inflamm, trauma/toxin, genetic)
CS associated with chr. kidney dz
WL, PU/PD, ↓ appetite and old age
(more likely in cats)
↓ nutrition status and poor hair coat
Dx chr. kidney dz
↑ azotemia and ↓ USG
Persistent glomerular proteinuria, non-regen anemia, and genetic biomarkers of inherited kidney dz
NEXT STEP: IRIS stage
Anatomical kidneys signs associated with chr. kidney dz
Small kidneys, mineralization and cysts/ pseudocysts
What are the stages of chr. kidney dz based on?
Elevated serum creatinine
1. Azotemia (if hydrated)- pre (non kidney), renal (kidney failure), post (obstruction)
2. Substage with proteinuria and hypertension
Stage 1 of chr. kidney failure
Inadequate urine conc. ability (cats)
Progressive ↑ in creat/ SDMA
Renal abnorms (imaging)
Persistant renal proteinuria
↓ GFR
How to tx stage 1 of chr. kidney failure
Tx underlying dz
Renal therapeutic diet (tx proteinuria)
Keep P (phosphate binder)
Fresh H20 available
Stage 2 of chr. kidney failure
Mild (years survival)
Animal progresses
How to tx stage 2 of chr. kidney failure
Renal therapuetic diet
Tx hypokalemia (cats)
Same as stage 1
Stage 3 of chr. kidney failure
Moderate
Complication: hypertension
Anemia and poor appetite
How to tx stage 3 of chr. kidnye failure
Keep P
Tx met. acidosis, anemia, V, inappetence and nausea
↑ fluids
Calcitriol tx (dogs)
Same as 2
Stage 4 of chr. kidnye failure
Severe (week- month survival)
Creat >5 (bad CS)
Complication: infection
How to tx Stage 4 of chr. kidnye failure
Feeding tube for nutrition and hydration
Same as 3
What does progressive chr. kidney dz look like?
Glomerulosclerosis
Tubulointestinal injury
Cell death
Mechanisms promoting progression
Hypoxemia, hyperphosphatemia, hypertension, renal proteinuria, persistence/ recurrence of initial or new cause, advancing age
EG toxicity (acute kidney dz)
Once azotemic 100% die
Ca oxalate crystals in urine (death soon)
Severe met. acid and ↑ anion gap seen before azotemia and crystals
Significance of EG
Dx b4 azotemia
Normal creat. doesn’t rule out AKI
Urinalysis in initial evaluation if you suspect kidney dz
Acute kidney dz
Sudden and rapid decline in kidney function <1w
Anion gap
Helps localize aciodsis
(Na + K) - (Cl +HCO3)
Norml: 15-25
How to dx AKI
Historical data (EG, lilies, grapes, etc)
Clinical markers (renal pain, oliguric)
Lab data (↑ creat, cystatin B, UA, MDB)
What can cause AKI
Hemodynamic (hypovelmia, hypotension, shock, anesthesia)
Infectious (lepto)
Nephrotoxicity (EG, grapes, NSAIDs)
Systemic Dz (sepsis)
Urinary obstruction (ureteral)
CS associated with AKI
Oligonuria, kidney pain and enlargement
Lethargy, anorexia, V/D, PU/PD, WL
Phase 1 of AKI: Initiation
GFR goes to 0 right away
Creatinine low or normal
Specific therapy can halt damage
Phase 2 of AKI: Extension
Continues damage
Specific/ supportive therapy can halt damage + permit renal repair
Phase 3 of AKI: Maintenance
Measures ↓ kidney function
1-3w
Oliguria
Targeted supportive therapy (allows kidney time to repair)
Phase 4 of AKI: Recovery
Renal repair, not all recover
Weeks to months
Urine output ↑
Consequences: CKD/ death (50%)
Most important step for tx AKI
Correcting prerenal azotemia
1. Correct perfusion within first hrs to dx
2. Correct dehydration over 12-24 hrs
What is the most common error when dx AKI?
Failure to perform the urinalysis
Other ways to dx AKI
Glucosuria without hyperglycemia (tubular damage and proteinuria)
↓USG (with ↑ azotemia)
Urine sediment
What seen in a urine sediment of a pet dx with AKI
Acute tubular necrosis: granular casts (muddy brown) with epithelial cells and casts
Ca oxalate crystals (EG, hypocalcemia)
Glomerunephritis/ vasculitis: proteinuria, red cells and red cell casts
Interstitial nephritis/ pyelonephritis: Polyuria and WBC casts
How to tx AKI
Specific therapy: eliminate, remove underlying cause
Supportive (water, electrolyte, calorie, acide/base correction, removal of retained wastes, endocrine)
Symptomatic therapy: nausea and pain
How to tx persistent oliguria
Patients remaining oliguric after complete rehydration
Therapeutic trial with diuretics (don’t give unless completely hydrated)
What drugs to use for AKI
Mannitol (osmotic diuretic)
Glucose (OD)
Furosemide (loop diuretic)
Fenoldopam/ dopamine (vasodilation ↑ renal blood flow and naturesis)
Diltiazem (Ca channel blocker causing preglo vasodilation)
Pathologic oliguria/anuria
Small urinary bladder, hyperkalemia, urinary obstruction and uroabdomen
What does pathologic oliguria/anuria lead to?
azotemia, fluid overload, met acidosis
Pathologic nonoliguria and polyuria
Large urinary bladder and hypokalemia
What does nonpathologic oliguria/polyuria lead to?
Signals onset of recovery of AKI
Dehydration and hypokalemia
Leptospirosis
Common cause of AKI in dogs
PCR accurate (abx and test timing disrupt)
Confirm with convalescent Ab titer
Indications for Renal Replacement Therapy
Fluid overload
Unrelenting hyperkalemia acid/ base imbalance
Inadequate urine production
Progressive unrelenting azotemia
Acute poisoning/ drug overdose
