Urology/Nephrology Flashcards
What are the 3 substances/hormones produced by the kindey?
Erythropoietin
1,25-Dihydroxycholecalciferol
Renin
What is azotemia?
Abnormal increase in the concentration of non-protein nitrogenous wastes (eg urea and creatinine)
What is renal failure?
Clinical syndrome when the kidney is no longer able to maintain
Regulatory function
Excretory function
Endocrine function
Renal failure occurs when >_____% of the nephrons are non functional
75
T/F: you will always see azotemia in renal disease
False
Requires 75% nephron loss to have azotemia
What is a uremia?
Clinical signs associated with critical loss of functional nephrons
What are the extra-renal manifestations of renal failure, which is aka uremic syndrome
Azotemia
Hypoalbuminemia
Hypercholesterolemia
Metabolic acidosis
Hyperkalemia
Hypocalcemia
Increased PTH
What are the methods of direct measurement of GFR?
Clearance of radioisotope with renal scintigraphy
Iohexal
Inulin
Creatinine clearance tests
What are INDIRECT methods of measuring GFR?
Serum urea levels
Serum creatinine
Cystatin C
SDMA
Serum levels of urea are affected by??
Species/age Liver function Dietary protein content Endogenous protein catabolism Renal function
Urea is synthesized in the __________ from???
Liver; ammonia and protein in GI tract/muscle breakdown
Why is urea not a reliable estimate of GFR?
Passively reabsorbed in the tubules —> can be exacerbate by slower tubular flow rates (dehydration/hypovolemia)
False positives - GIT bleeding, intravascular hemolysis, and high protein diets
Where is creatine synthesized?
Breakdown of creatine phosphate in muscles
- > produced at a constant rate
- > dependent on muscle mass
- > influenced less by diet
What are causes of increased serum concentrations of creatinine?
Reduced renal clearance
What are causes of decreased serum concentrations of creatinine?
Reduced muscle mass
Which is a better indication of GFR, creatinine or urea?
Creatinine
T/F: severity of renal disease is proportional to the increased creatinine
False
Cannot prognosticate based on magnitude of azotemia
What is cystatin C?
Small polypeptide protease inhibitor produced by all cells with nucleus
T/F: cystatin C is freely filtered by glomeruli and is almost completely reabsorbed by proximal tubular cells
True
Where is SDMA produced?
In every cell, released into circulation during protein degredation
SDMA is increased when there is a _____% decline in GFR
40
How can urine be collected?
Free flow
-> cannot be used for culture
Catheterization
-> difficult in females
Cystocentesis
BEST method
-sterile sample
What are components of a urinalysis?
Colour/clarity Dipstick Concentration Sediment urine protein:creatinine ratio
What are the useful tests in a dipstick analysis of urine?
Protein PH Blood Glucose Ketone
How do we measure urine concentration
Refractometer
-calibrated with distilled water-> should measure 0
What can cause a falsely increased USG?
Glucosuria
Proteinuria
What is the USG for hyposthenuria?
1.000 - 1.007
What is the USG for isosthenuria ?
1.008-1.012
Minimally concentrated urine has a USG of?
1.013-1.030
What is the USG for adequately concentrated urine in dogs and cats?
Dog > 1.030
Cat> 1.035
Case History of trauma Dog with PU/PD UA -USG 1.005 -dipstick normal
What are possible DDX ?
Hyposthenuria
- diabetes insipidus (central or nephrogenic)
- cushings
- psychogenic
For a hyposthenuric dog, your top DDX are.. Diabetes insipidus, psychogenic polypidpisa, and hyperadrenocortisim. What do you do next?
Rule out..
hyperadrenocortisim with a urine cortisol:creatine ratio
Partial water deprivation test
When doing a partial water deprivation test, when do you see maximal ADH release?
After 5% loss of body weight in water
Failure to concentrate with partial water deprivation test rules out?
Rules out psychogenic polydipsia
Left with diabetes insipidus
How can you differentiate between central and nephrogenic DI?
Give desmopressin
- > concentrate urine = central
- > non concentrated = nephrogenic
When doing a urine sediment, what are you looking for?
Cells
Bacteria
Crystal
Casts
What can cause a false positive UPC?
Cloudy urine
How can you determine is a proteinuria is due to renal disease or not?
Urine protein:creatinine ratio
> 0.5 tubular/glomerular disease
What are non-renal causes of proteinuria?
Hemorrhage
UTI/cystitis
Intravascular hemolysis (hemoglobinuria)
What test can you use to find a transitional cell carcinoma?
Bladder tumors antigen test
88% specificity
What is the most common bacteria found in UTI?
E. coli
Gram negative aerobic
Also common bacteria in contaminated samples
When doing a kidney biopsy, what part of the kidney should you take your sample from?
Cortex
What is hematuria ?
Presence of blood in ruine
What can cause a pseudohamturia?
Hemoglobinuria, myoglobinuria, or chemicals
Where can heamaturia originate from?
Systemic disorder
Renal
Bladder, ureter, urethra
Genital tract
What disease of the kidney can cause hematuria?
Neoplasia, calculus, trauma, infarction, cyst, glomerulonephritis, and infection
What can cause a hematuria arising from he bladder/ureter/urethra?
Bacterial infection Calculi Trauma Neoplasia Polyps Cyclophosphamide Feline idiopathic cystitis
What genital tract conditions can cause a hematuria?
Prostatic disease, oestrus, infection, neoplasia, and trauma
What diagnostics can you do in a case of hematuria?
Hematology/blood smear Biochem UA and cluture Imaging (US) Cystoscopy Vaginoscopy Prostatic wash
What are clinical signs of kidney disease?
PU/PD Anorexia/ GI signs/ weight loss Pale mucous membranes Lethargy Blindness Distended abdomen
What are signs of lower urinary tract disease?
Inappropriate urinating
Pollakiuria, dysuria, stranguria
Hematuria
You have a patient with a disorder of micturition, what should your clinical exam include?
Vitals, body score, and hydration status
Palpate kidney
Oral - uremic stomatitis Rectal -prostate Bladder palpitation Neuro exam Ophthalmic exam
Young animals -fibrous osteodystrophy
Perineum -odor, urine scald, folds
Vaginal exam-discharge/masses
T/F: you always have a low USG with acute kidney disease
False
What are causes of renomegaly?
Primary
- renal adenocarcinoma
- renal lymphoma
- renal sarcoma
- nephroblastoma
Metastatic (rare)
T/F: renal carcinoma is more common in dogs than cats
True
Clinical signs associated with renal carcinoma?
Hematuria and weight loss
Unilateral renomegaly
Rarely azotemia
Polycythemia as a paraneoplasic syndrome —> EPO production
Hypertrophic osteopathy as paraneoplastic syndrome
How can you diagnose renal carcinoma?
Renal ultrasound
FNA
What is the treatment for renal carcinoma?
Ensure sufficient rxn in contralateral kidney
Nephrectomy
Prognosis is about 16months
T/F: renal lymphoma is more common in cats than dogs
True
T/F: renal lymphoma usually only affects one kidney
False
Both
What is the presentation of renal lymphoma?
Renomegaly
Weight loss
Inappetance
PU/PD
Azotemia
Systemic
CNS spread
What is the treatment for renal lymphoma?
Chemotherapy
60% of cats go into remission
What are the non-neoplasic causes of renomegaly?
Inflammation -nephrosis -pyelonephritis -FIP -lepto Amyloidosis Hydronephrosis Polycystic kidney dz Portosystemic shunt
Acute urethral obstruction (cats)
What breed is polycystic kidney disease prevalent in?
Persian cats
Autosomal dominant gene - mutant PKD1
Also in…
bull terriers
Carin terriers
WHW terriers
