Chronic Kidney Disease

Question 1

CKD and CRF

Answer 1

Irreversible and progressive loss of kidney structure/function

• CKD = CRF
• 1-3% of geriatric cats
• 0.5-1% of geriatric dogs

Question 2

Causes of CRF/CKD

Answer 2

• chronic interstitial nephritis (idiopathic)
• pyelonephritis
• glomerulonephritis
• amyloidosis
• polycystic kidney dz
• hypercalcemic nephropathy
• hydronephrosis
• familial renal dz
• renal dysplasia
• neoplasia
• following AKI

Question 3

CKD progression

Answer 3

Loss of nephrons –> decrease GFR –> compensation

• up to 60% increase in nephron GFR
• supernephron

Question 4

Compensation leads to ______

Answer 4

Premature deterioration of remaining nephrons

• isosthenuria: 66% lost
• azotemia: 75% lost

Question 5

History

Answer 5

• PU/PD
• vomiting, anorexia, weight loss
• lethargy, weakness
• neurologic: twitching, seizures

Question 6

Physical exam

Answer 6

• poor body condition
• oral ulcers, uremic breath
• dehydration
• small, irregularly shaped kidneys
• blindness (hypertension)

Question 7

Diagnostics

Answer 7

• CBC
• chem
• UA –> proteinuria is a negative prognostic indicator
• bp, fundic exam
• radiographs
• ultrasound

Question 8

Major clinicopathologic abnormalities

Answer 8

• azotemia (isosthenuria)
• hyperphosphatemia
• acidosis
• anemia (EPO deficiency)
• +/- proteinuria
• +/- UTI
• hypokalemia

Question 9

Radiographs

Answer 9

Small, irregular kidneys

- urolithiasis

Question 10

Ultrasound

Answer 10

• hyperechoic renal cortices (loss of corticomedullary junction)
• urolithiasis
• pyelonephritis

Question 11

Hypertension

Answer 11

• > 160 mm Hg
• 25% of patients
• due to RAAS activation

Question 12

IRIS staging

Answer 12

Based on:

• creatinine concentration
• proteinuria
• hypertension

Question 13

Treatment goals

Answer 13

Delayed progression of disease

• extended survival time
• improved quality of life

Question 14

Management goals

Answer 14

• treat underlying cause
• maintain hydration
• diet modification
• treat anemia
• treat hypertension
• manage vomiting
• correct metabolic derangement (acidosis, hyperphosphatemia, hypokalemia)

Question 15

Hydration

Answer 15

PU/PD, dehydration –> decreased renal perfusion

- encourage water intake

Question 16

Dietary modification

Answer 16

• protein restriction
• phosphorus restriction
• alkalinization
• omega 3 FAs
• palatability

Question 17

Anemia

Answer 17

Can be severe, decreased erythropoietin

- blood transfusion, recominant human EPO

Question 18

Hypertension

Answer 18

Arterial BP>160 mm Hg

• common
• lead to further glomerular damage
• ACE-inhibitors, amlodipine

Question 19

Manage vomiting

Answer 19

Increase gastrin levels (H2 blockers, proton pump inhibitors)
- anti-emetics

Question 20

Metabolic acidosis

Answer 20

• decrease acid excretion
• diet
• sodium bicarbonate

Question 21

Hypokalemia

Answer 21

Common in CKD cats

• decreased ingestion, increase loss
• oral potassium supplementation

Question 22

Hyperphosphatemia

Answer 22

Can be severe

- diet, phosphate binders

Question 23

Calcitriol

Answer 23

Counteracts renal secondary hyperparathyroidism

• [calcitriol] is low w/ CKD
• calcitriol inhibits PTH production
• control [P] prior to initiation to improve survival in dogs

Question 24

AKI/CKD - reversibility

Answer 24

AKI - yes

CKD - no

Question 25

AKI/CKD - prognosis

Answer 25

CKD - survive some period after diagnosis

AKI - short term mortality 50% (may recover to clinically normal)

Question 26

Ways to differentiate AKI/CKD

Answer 26

• BCS
• renal size
• anemia
• severity of azotemia vs clinical signs
• biopsy