Clinical Pathology Laboratory - Urinalysis Protocols

Collection protocol

Frequently asked questions

Instruments:

Samples are analyzed using Multistix urine dipsticks (Siemens Healthcare Diagnostics Inc., Deerfield, IL), and refractometry and light microscopy.
 

Sample Requirements:

Urine collected by free catch, catheterization or cystocentesis may be submitted.  Sterile/aseptic collection technique, when possible, is recommended to prevent fecal and environmental contamination.

Tests Available:

Urinalysis tests

* Occasionally, smaller volume samples may be accommodated.  Please contact the lab regarding submission of these samples and the testing that is available.

Appropriate Tubes: 

Urine may be submitted in any sterile, additive-free, plastic or glass container of appropriate volume, including syringes, Eppendorf tubes, and plain red top tubes.

Sample Handling:

Label samples using permanent marker with a legible, simplified numbering system.  For dipstick, specific gravity and sediment examination, samples should be refrigerated as soon as possible following collection and must be analyzed within 24 hours for valid results.  They should not be frozen or transported directly on ice.  Transport with cold packs is recommended.  Chemistry tests on urine have prolonged stability.  Please contact the lab directly if you wish to submit frozen or archived urine samples for chemistry tests.

Results:

Parameters generated from the urine dipstick include semi-quantitative measurement of urobilinogen**, protein, pH, blood***, ketones****, bilirubin and glucose.  Confirmatory tests for the presence of bilirubin (Ictotest), ketones (Acetest, acetoacetic acid) and protein (sulfasalicylic acid precipitation test, SSA) may be performed if there is a positive result on the dipstick.  Urine specific gravity is measured via refractometry.  Sediment examination evaluates for the presence of red blood cells, white blood cells, epithelial cells, crystals, casts, sperm, lipid/fat and bacteria or fungus.

Common Interferences:

Samples with marked blood contamination/hematuria, hemoglobinuria and bilirubinuria may result in color interference with dipstick parameters.  Oral ascorbic acid supplementation may result in false negative urine glucose.  Bleach, peroxide and other strong oxidizing agents may result in false positive urine glucose.  Quarternary ammonium compounds and highly alkaline urine may result in false positive urine glucose.
 

* Occasionally, smaller volume samples may be accommodated.  Please contact the lab regarding submission of these samples and the testing that is available. 

** Urobilinogen is only reported out in non-human primate samples, as it is not considered to be reliable or valid in most veterinary species. 

*** Intact red blood cells, myoglobin and hemoglobin may each result in a positive dipstick reaction for blood. 

**** Acetoacetic acid is the only ketone measured by the urine dipstick.  Other undetected ketones (beta-hydroxybutyrate, acetone) may be present in the urine of veterinary species.