Chronic Kidney Disease

Question 1

How many nephrons need to be lost before azotaemia occurs?

Answer 1

75%

Question 2

What happens to the remaining nephrons when other nephrons die?

Answer 2

Hyperfiltrate - increase their GFR to preserve overall renal function

Question 3

Is it possible to have chronic kidney disease without azotaemia?

Answer 3

Yes

IRIS stage 1 and some stage 2

Question 4

What can IRIS staging be based on?

Answer 4

1 to 4

Createnine
UPC
blood pressure

Question 5

How is blood pressure affected by CKD?

Answer 5

Hypertension

Question 6

What is a basic management approach for CKD?

Answer 6

Determine underlying cause

Control factors important in disease progression

Reduce patient morbidity

Question 7

What causes CKD in cats?

Answer 7

Lymphoma 
PKD 
FIP
Amyloidosis 
Primary Glomerular disease 
Pyelonephritis 
Toxins 
Recovery from AKI
Obstructive nephropathy 
Chronic tubulointerstitial nephritis

Question 8

How can you diagnose polycystic kidney disease?

Answer 8

Breed predisposition - Persians

Kidneys palpably enlarged in azotaemic cat

Can be detected via US before Azotaemia occurs (usually middle age)

DNA test possible

Question 9

What is obstructive nephropathy known as colloquially?

Answer 9

Big kidney little kidney syndrome

First Blocked kidney -> little

Question 10

What tends to obstruct cats in obstructive nephropathy ?

When are clinical signs seen?

Answer 10

Calcium oxalate

When obstruction bilateral

Question 11

What is tubulointerstitial nephritis in cats?

Answer 11

Histologically description

End stage appearance of CKD regardless of inciting cause

Nephrons have died and been replaced by fibrosis and inflammatory infiltrate is present

Question 12

What are the key causes of chronic kidney disease in dogs?

Answer 12

Tubulointerstitial nephritis

Familial (breed related) disease syndromes

Primary glomerular disease

(Pyelonephritis, post AKI)

Question 13

When would you perform diagnostic imaging on CKD patients?

Answer 13

Young animals 
Dogs - harder to palpate
Asymmetric kidneys
Large kidneys 
Severe proteinuria 
Uncertain chronicity

Question 14

What are the putative mechanisms for progression of renal disease?

Answer 14

CKD - mineral bone disorder

Glomerular hypertension

Direct proteinuria induced renal injury

Other mechanisms - acidosis, hypokalaemia

Question 15

How can we reduce MBD and increase survival time in CKD patients?

Answer 15

Dietary phosphate restriction

Question 16

How can systemic hypertension affect urine parameters?

Answer 16

Glomerular capillary hypertension

PROTEINURIA

Question 17

How can proteinuria be minimised in CKD patients?

Answer 17

Reduce glomerular pressure with ACE inhibitors or ARBs

Question 18

When should ACE inhibitors be considered?

Answer 18

Proteinuric patients
Earlier in CKD
=Preserves nephrons long term but will be dangerous for advanced stage patients

Question 19

What factors contribute to morbidity in CKD?

Answer 19

UTIs
Anaemia 
Dehydration
Hypokalaemia 
Acidosis 
Systemic hypertension

Question 20

Which patients are more likely to be hypokalaemic?

What causes this?

What CS?

Answer 20

Cats

Decreased appetite, increased urinary losses, hyperaldosteronism esp if hypertensive.

Muscle weakness