Urine collection: freeflow

• Collection of fresh urine sample allows urinalysis to be performed.

• Collection of urine sample for:
  • Glucose measurement Urinalysis: glucose when diagnosing or monitoring diabetic patients Diabetes mellitus.
  • Gross examination of urine for discoloration Discolored urine, eg hematuria, bilirubinuria, myoglobinuria (but gives no indication of source of discoloration, ie renal, cystic or lower urinogenital tract).
  • Measurement of specific gravity Urinalysis: specific gravity in assessing renal function .
  • Biochemical urinalysis (usually in assessment of renal function ).
  • Sediment examination for presence of casts in diagnosis of renal tubular disease Urinalysis: centrifuged sediment.
  • Sediment examination for presence of crystals in diagnosis of urolithiasis Urolithiasis.

Advantages

• Non-invasive.
• Requires no specialized equipment - can be performed by owner at home.
• Usually provides adequate sample for analysis.

Disadvantages

• Rarely useful in cat as requires animal to urinate voluntarily (may result in delay in urine collection).
• Contamination may make bacterial culture unreliable.
• Cannot discriminate between urine produced in upper urinary tract and contamination of sample in lower urinogenital tract.
• Not appropriate if animal has urinary tract obstruction.

• Urinary catheterization Urethra: catheterization.
• Cystocentesis Cystocentesis.

Preparation

• None required.

Procedure

• As long as it takes for the animal to urinate voluntarily.

Criteria for choosing test

• The reason for urine sample collection has an influence on the most appropriate method of collection.
• Samples for bacterial culture should be collected in a sterile manner preferably by cystocentesis.
• Requirement for regular urinalysis, eg urine glucose monitoring in diabetics, necessitates owner involvement and freeflow samples are adequate.

Minimum consumables

• Clean container for collecting urine.

Ideal consumables

• Urine collection vessel should be sterile and may contain preservative (depending on sample analysis required).
• Collecting urine samples may be difficult - flat urine collection trays may be useful.

Step 1 - Urine collection

• When the animal begins to urinate pass the urine collection vessel into the flow of urine.
• Experienced personnel may encourage the flow of urine by gentle pressure on the abdomen.

Step 2 - Alternative method

• Urine collection can be made from a sample passed onto a clean non-absorbant surface by means of a syringe.
• In most cases this can be achieved by confining patient in cage with empty litter tray and waiting for sample to be passed.
  Samples collected in this way are not suitable for culture due to risk of unknown contamination.

Step 1 - Urine storage

• Sealed containers should be refrigerated until examination.
• If samples are to be stored or there is delay in transport to the laboratory the sample can be transferred to a container with formalin or thymol preservative.

Refereed papers

• Recent references from PubMed and VetMedResource.