Urine Culture
Test Code
CXURI
Description
Urine culture is used to determine whether bacteria or yeast may be causing a urinary tract infection (UTI). UTIs are typically caused by one, or possibly two, organisms. Detection of three or more organisms in urine usually indicates that normal urethral flora has contaminated the sample during collection, and another sample should be collected and submitted.
Collect
Clean catch: Sterile screw-cap cup or Vacutainer Urine C&S Transport System (grey top)
Indwelling and Straight catheter: Sterile screw-cap cup or tube, Vacutainer Urine C&S Transport System
Suprapubic aspirate: Anaerobic transport system or capped syringe without needle
Preferred: Vacutainer Urine C&S Transport System. Must be filled to the line to avoid inhibiting bacteria growth (~3ml of urine)
Preferred volume without preservatives: 3 mL
Minimum Volume without preservatives: 0.5 mL
Patient Prep
- Avoid antibiotic administration prior to sample collection.
- Obtain early-morning specimens whenever possible because of increased bacterial counts after overnight incubation in the bladder. The best yield is 4 hours since the last void.
- Do not force fluid intake in order to have the patient void urine. Excessive fluid intake will dilute the urine and may decrease the colony count or result in a false-negative culture.
Instruct patients on clean catch procedure:
- Females should use a packaged, moist towel to clean the vulva and perianal areas starting from front to back. Repeat with a second moist towel. Females should then spread their labia with one hand and start urinating into the toilet. With the other hand, they should put the urine container under the genital area to catch the mid-stream of urine without touching any skin. This is called a "clean-catch" urine.
- Males should retract the foreskin from the penis if necessary and use the packaged towel to clean the penis from the tip to the base. Repeat with second towel. Males should retract the foreskin if applicable with one hand and start urinating into the toilet. Then, position the urine container with the other hand to catch the stream without touching any skin.
Unacceptable Conditions
- Specimens received outside of temperature storage requirements
- Specimens received outside of stability time frame
Specimens that do not meet the minimum volume requirement - Specimens in non-sterile containers
- Specimens in expired transport media
- Specimens from a source not acceptable for this testing
- Specimens that are excessively leaking
- Mislabeled or unlabeled specimen
- Foley catheter specimens
- Urine from a urinal, bed pan, or catheter bag
- Urine collected as part of a 24 hour collection
Stability
Unpreserved Urine:
- For optimal recovery of potential pathogens, specimens should arrive within 2 hours at room temperature (20-25°C)
- If transportation is delayed, specimens must be refrigerated (2-8°C) for a maximum of 24 hours
Preserved Urine:
- Specimens are stable at room temperature (20-25°C) for 2 days
Performed
7 days a week from 8am to 6pm
Methodology
Quantitative urine culture.
Turnaround Time
2 days
Department
Microbiology Lab
Study Offerings
CAP/CLIA
Reference Interval
- No growth
- <10,000 cfu/mL, no significant growth
Interpretation
A diagnosis of a UTI typically depends on how many organisms appear in the culture and the type and quantity of the predominant organism recovered.
|
Culture growth |
Amount of growth |
|
|
One or two uropathogens |
≥ 100,000 CFU/ml |
Considered a likely UTI in adults |
| ≥ 50,000 CFU/ml | Considered a likely UTI in children | |
|
≤ 10,000 CFU/ml |
Not typically considered a UTI, except in some circumstances (e.g. suprapubic aspiration) | |
| Mixed urogenital flora | Any | Typically not significant |
| Three or more organisms (except certain organisms such as N. gonorrhoaea or S. agalactiae in women of child-bearing age) | Any | Typically represents contamination |
The table below describes possible reportable organisms and when antimicrobial suscecptibility testing (AST) is routinely included. If susceptibilities are needed for an organism that AST is not routinely included, please submit the request through EPIC using the OP Add-On/Comm Message type addressed to NJH LAB ADD-ON POOL.
|
Organism grown |
Testing performed |
|
Gram-negative bacilli |
ID and AST |
|
Staphylococus aureus |
ID and AST |
|
Enterococcus spp. |
ID and AST |
|
Beta-hemolytic Streptococcus spp. |
ID |
|
Neisseria gonorrhoeae |
ID |
|
Yeast |
ID |
|
Aerococcus urinae |
ID |
|
Actinotigum schaalii |
ID |
|
Alloscardovia omnicollens |
ID |
CPT Code
87086
New York Approved
Standard
FDA
Standard Method