Urinalysis Flashcards
(25 cards)
Three parameters that are observed from urine sample
- Physical changes (turbidity, odor, concentration, color)
- Chemical (pH, protein, glucose, biliruin, ketones)
- Sediment
Native - crystals, casts
Cytology - blood cells, bacteria, other cells
Cloudiness in urine could be caused by
Elevated RBC and WBC
Bacteria
Crystals
Semen
Concentration (USG) is used to
Urine specific gravity
Used to assess tubular function of kidneys and the kidneys ability to concentrate urine (ability decreases when 2/3rd of the tubules are damaged
How is USG measured?
By using a refractometer
Normal USG values for dog and cat
Dogs - 1.015-1.045
Cats - 1.035-1.060
How can USG be used in a patient with azotemia?
Can be used to evaluate kidney function and localize the cause for azotemia
Adequate concentrating ability –> pre-renal azotemia
Inadequate concentrating ability –> renal azotemia
What’s measured with dipsticks?
pH
Protein
Glucose
Ketones
Bilirubin
Heme
(leukocytes, USG, nitrits, urobilinogen are inaccurate or unimportant)
Normal pH in dogs and cats
acidic pH 5,5-7,0
What crystals are found in acidic urine? Alkaline?
Acidic urine - Struvites
Alkaline urine - Oxalates
Glucosuria is caused when…
blood glucose levels exceeds the renal threshold (dogs 9,9mmol/l, cats 16,5mmol/l)
Can be caused by diabetes mellitus, hyperadrenocorticism, acromegaly, kidney disease, stress (cats)
Causes for proteinuria
Pre-renal - hemoglobinuria, myoglobinuria
Renal - Protein-losing nephropathy, glomerular diseases
Post-renal - blood contamination, bacteria
What could cause ketonuria?
Negative energy-balance
-Diabetic ketoacidosis
-Malnutrition, carbohydrate-poor diet
-Constant hypoglycemia
Three possible causes for heme in urine
-Hemauria (heme from blood)
-Intravascular hemolysis (heme from hemoglobin)
-Muscle damage (heme from myoglobin)
Bilirubin in urine?
Bilirubinuria
Urine is dark yellow or greenish
Main causes - hepatobiliary diseases and extravascular hemolysis
Small amount of bilirubin is normal in dogs
Leukocytes in dipstick?
Dipstics are designed to measure human leukocytes so it’s inaccurate –> confirm with microscope
What do you check with microscope from unstained native sample?
Crystals and casts
What do you check with microscope from a stained sample?
Erythrocytes
Leukocytes
Epithelial cells
Microorganisms
What are casts?
Structures that are produced in kidney tubules from different proteins and cells.
Some can be normal, some can indicate disease.
Causes of hematuria
-Urinary tract: inflammation, trauma, neoplasia
-Parasites
-Coagulopathies (rodenticides, thrombocytopenia)
-Kidney infarction
-Genital tract
-Iatrogenic (method of collection)
Epithelial cells in urine?
Small amounts can be normal, larger amounts are indicative of a disease.
Different kind of cells are connected to different places, for example
Squamous epithelial cells –> lower urinary tract
Transitional epithelial cells –> renal pelvis and proximal urethra
Pyuria
Bacteria + degenerated inflammatory cells
Bacterial cystitis, pyelonephritis, prostatis
Main bacteria found in urine?
E. coli
Proteus spp.
Staphylococcus spp.
Streptococcus spp.
Fungi in urine?
Usually a sign of contaminated or old urine
If fresh and collected with a sterile method –> primary kidney or bladder fungal disease
Parasites in urine?
Capillaria plica, Capillaria feliscati (bladder worm)
Dioctophyma renale (kidney worm)
