What is the difference between kidney disease and renal failure?
Kidney disease can be asymptomatic (8 month old kitten diagnosed with polycystic kidney disease but has normal blood test results), while renal failure will have abnormal blood results and show signs of disease.
What is the difference between uremia and azotemia?
Azotemia is the accumulation of non-protein nitrogenous waste products in the blood/serum/plasma; uremia is the constellation of clinical signs that result from azotemia.
What is the staging scheme for chronic kidney disease (CKD)?
Separated into 4 stages, characterized by the concentration of creatinine in plasma along with clinical signs (or lack of clinical signs).
-Stage I: non-azotemic
-Stage II: non-azotemic to mildly azotemic
-Stage III: mild to moderate azotemia
-Stage VI: moderate to severe azotemia
What are some clinical signs of CKD?
-Clinical signs of more than 2 weeks duration
-Anorexia, weight loss
What can be seen on physical examination in cases of CKD?
-Poor body condition
-Pale mucus membranes (if kidneys are not producing erythropoietin, can be anemic)
-In end-stage uremia, will see oral ulceration and altered mentation
-Ascites/peripheral edema (due to hypoproteinemia)
-Hypertensive retinopathy, hyphema
-Cervical ventroflexion (hypokalemia)
How is CKD managed?
1. Search for underlying disease
2. Control factors important in disease progression
3. Control factors that increase patient morbidity
What are some causes of CKD in the cat?
-Polycystic kidney disease
-Chronic tubulointerstitial nephritis
In what type of breeds is polycystic kidney disease common?
Persian and related breeds; autosomal-dominant inheritance.
When can polycystic kidney disease be detected ultrasonographically? When does azotemia generally occur?
-Can be detected from 8 months of age via ultrasound
-Azotemia doesn't develop until middle age
What is obstructive uropathy?
It occurs when small stones obstruct the outflow of urine from the kidney. Typically obstruction of the first kidney is asymptomatic, but will develop clinical signs when the second kidney obstructs. On contrast (injected) radiography, will see enlarged renal pelvis and fail to see the contrast progress down the ureters.
What is chronic tubulointerstitial nephritis?
Multifocal fibrosis of variable severity caused by infiltration of lymphocytes and plasma cells. Soft tissue mineralization and tubular dilation and atrophy will occur.
What are some causes of CKD in the dog?
-Familial nephropathies (amyloidosis, renal dysplasia, glomerulopathy)
-Others (such as pyelonephritis)
Is proteinuria of prognostic significance?
Yes! Proteinuria is associated with a worse prognosis in both dogs and cats with CKD.
What is the effect of ACE inhibitors on glomerular pressure?
Decreases the glomerular pressure by dilating the afferent and efferent arterioles (efferent dilates more than afferent).
What is the effect of ACE inhibitors in dogs?
Proven benefit in dogs with proteinuric kidney diseases (glomerulonephritis and certain forms of familial nephropathy).
When should ACE inhibitors be used in patients with CKD?
-Animals with higher UPCs
-Patient needs to be relatively stable
What are factors that contribute to morbidity in CKD?
What about feline urine makes it resistant to infection?
High osmolality of feline urine makes it very resistant to infection.
What are some reasons for hypokalemia?
-Tends to be a problem in cats with CKD
-Decreased intestinal absorption