the complete urinalysis Flashcards
what are the 3 parts of the complete urinalysis
- macroscopic
- chemical analysis
- microscopic examination
what factors affect urine volume and concentration?
- eating
- drinking
- metabolism
- various diseases
- species
- body size and weight
- physical activity
- environment
what can the urinalysis be used to determine?
- pathogenic disorders (renal failure, inflammation/infection, crystalluria, neoplasia, Fanconi syndrome, diabetes mellitus, hepatic disease, systemic acidosis)
What tests can be run using urine that is NOT collected either in a metabolism cage or via catheterization and collection bag?
qualitative and semi-qualitative determinations
describe the early morning urine sample
- more concentrated
- facilitates evaluation of tubular capacity to concentrate urine without special techniques
- will most likely contain a higher yield of cells, casts, and bacteria because of the duration of formation, the probability of the sample being acidic (which preserves cells), the concentration of the urine (which tends to be closer to the cosmological pressure of the cells)
- less likely to reveal hyperglycemic glucosuria than a 1-3 hour-old sample
- cell cytology may be altered with age
describe a recently formed urine sample
- superior cytological detail
- typically taken via cystocentesis
- sadly fewer cellular compound
- fastidious bacteria inhibited by urine may be easier to detect
- sample may not be sufficiently concentrated to allow for evaluation of tubular function
- a diluted sample may cause lysis of distortion of cells (especially RBCs and WBCs)
what is the normal urine volume for adult cats and dogs
20-40ml/kg/day
what is used to accurately measure urine output?
a metabolism cage
in the average animal hospital, what is used to indicate if an animal urine output volume is being produced?
specific gravity
what is specific gravity determined by?
the quantity and weight of dissolved particles
what can artificially elevate a specific gravity result?
glucose (because it is heavy)
- what the urine to be negative for glucose on the dipstick
polyurea typically results in a ______ specific gravity
low
(<1.030)
Oliguria typically results in a _______ specific gravity
high
(>1.030)
what is typically the cause of anurea?
an obstruction in the kidney
how may fluids and diuretics affect urine results?
alters specific gravity and osmolarity
what is the specific gravity of dilute urine
<1.008
What effect does dilute urine have on cells?
may cause lysis
what effect may formaldehyde have on urine?
- inhibit glucose oxidase and peroxidase systems
- may interfere with tests for bilirubin
penicillin, cephaloridine, and sulfisoxazole have been reported to give _________________
falsely positive reactions for protein detection by sulfosalicylic acid
how may ampicillin and sulfa drugs affect the urine?
may crystallize out in urine
what effect may acidifiers and alkalinizers have on urine?
- may alter crystal composition in addition to urine pH
- false positive reaction for protein
- false negative reaction with sulfosalicylic acid
- false positive for glucose if using a copper reduction method
- false negative for glucose if using oxidase methods
- ascorbic acid may inhibit the reduction of nitrate to nitrite
how may radiographic contrast agents affect urine
- commonly use triiodinated radiopaque contrast agents (eg. hypaque or renographin) may alter urine specific gravity and osmolarity
- if the specific gravity is <1.040 before contrast administration, it will typically rise after excretion of the contrast agent
- if the specific gravity is <1.040 before contrast administration, it will typically decrease after excretion of the contrast agent
- may cause false positive reactions for proteins detected by sulfosalicylic acid
