Culture, Bacterial, Urine

Culture, Bacterial, Urine

Synonym/acronym: Routine urine culture.

Common use

To identify the pathogenic bacterial organisms in the urine as an indicator for appropriate therapeutic interventions to treat urinary tract infections.


Urine (5 mL) collected in a sterile plastic collection container. Transport tubes containing a preservative are highly recommended if testing will not occur within 2 hr of collection.

Normal findings

(Method: Culture on selective and enriched media) Negative: no growth.


A urine culture involves collecting a urine specimen so that the organism causing disease can be isolated and identified. Urine can be collected by clean catch, urinary catheterization, or suprapubic aspiration. The severity of the infection or contamination of the specimen can be determined by knowing the type and number of organisms (colonies) present in the specimen. The laboratory will initiate sensitivity testing if indicated by test results. Sensitivity testing identifies the antibiotics to which the organisms are susceptible to ensure an effective treatment plan.

Commonly detected organisms are those normally found in the genitourinary tract, including gram negative Enterococci,Escherichia coli,Klebsiella,Proteus, and Pseudomonas. A culture showing multiple organisms indicates a contaminated specimen.

Colony counts of 100,000/mL or more indicate urinary tract infection (UTI).

Colony counts of 1,000/mL or less suggest contamination resulting from poor collection technique.

Colony counts between 1,000 and 10,000/mL may be significant depending on a variety of factors, including patient’s age, gender, number of types of organisms present, method of specimen collection, and presence of antibiotics.

This procedure is contraindicated for



  • Assist in the diagnosis of suspected UTI
  • Determine the sensitivity of significant organisms to antibiotics
  • Monitor the response to UTI treatment

Potential diagnosis

Positive findings in:

  • UTIs

Critical findings

  • Gram negative extended spectrum beta lactamases (ESBL) E. coli or Klebsiella
  • Gram negative Legionella
  • Gram positive Vancomycin-resistant Enterococci (VRE)
  • Note and immediately report to the health-care provider (HCP) positive results and related symptoms.

  • It is essential that a critical finding be communicated immediately to the requesting health-care provider (HCP). Lists of specific organisms may vary among facilities; specific organisms are required to be reported to local, state, and national departments of health.

  • Timely notification of a critical finding for lab or diagnostic studies is a role expectation of the professional nurse. Notification processes will vary among facilities. Upon receipt of the critical value the information should be read back to the caller to verify accuracy. Most policies require immediate notification of the primary HCP, Hospitalist, or on-call HCP. Reported information includes the patient’s name, unique identifiers, critical value, name of the person giving the report, and name of the person receiving the report. Documentation of notification should be made in the medical record with the name of the HCP notified, time and date of notification, and any orders received. Any delay in a timely report of a critical finding may require completion of a notification form with review by Risk Management.

Interfering factors

  • Antibiotic therapy initiated before specimen collection may produce false-negative results.
  • Improper collection techniques may result in specimen contamination.
  • Specimen storage for longer than 2 hr at room temperature or 24 hr at refrigerated temperature may result in overgrowth of bacteria and false-positive results. Such specimens may be rejected for analysis.
  • Results of urine culture are often interpreted along with routine urinalysis findings.
  • Discrepancies between culture and urinalysis may be reason to re-collect the specimen.
  • Specimens submitted in expired urine transport tubes will be rejected for analysis.

Nursing Implications and Procedure


  • Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
  • Patient Teaching: Inform the patient this test can assist in identification of the organism causing infection.
  • Obtain a history of the patient’s complaints, including a list of known allergens, especially allergies or sensitivities to latex.
  • Obtain a history of the patient’s genitourinary and immune systems, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures.
  • Obtain a list of the patient’s current medications, including herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus).
  • Note any recent medications that can interfere with test results.
  • Review the procedure with the patient. Address concerns about pain and explain that there should be no discomfort during the specimen collection. Inform the patient that specimen collection depends on patient cooperation and usually takes approximately 5 to 10 min.
  • Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
  • Note that there are no food or fluid restrictions, unless by medical direction.
  • Instruct the patient on clean-catch procedure and provide necessary supplies.


  • Potential complications: N/A
  • Ensure that the patient has complied with medication restrictions prior to the procedure.
  • Instruct the patient to cooperate fully and to follow directions. Direct the patient to breathe normally and to avoid unnecessary movement.
  • Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient, and label the appropriate collection containers with the corresponding patient demographics, date and time of collection, method of specimen collection, and any medications the patient has taken that may interfere with test results (e.g., antibiotics).
  • Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
  • Clean-Catch Specimen

  • Instruct the male patient to (1) thoroughly wash his hands, (2) cleanse the meatus, (3) void a small amount into the toilet, and (4) void directly into the specimen container.
  • Instruct the female patient to (1) thoroughly wash her hands; (2) cleanse the labia from front to back; (3) while keeping the labia separated, void a small amount into the toilet; and (4) without interrupting the urine stream, void directly into the specimen container.
  • Pediatric Urine Collector

  • Put on gloves. Appropriately cleanse the genital area, and allow the area to dry. Remove the covering over the adhesive strips on the collector bag and apply over the genital area. Diaper the child. When specimen is obtained, place the entire collection bag in a sterile urine container.
  • Indwelling Catheter

  • Put on gloves. Empty drainage tube of urine. It may be necessary to clamp off the catheter for 15 to 30 min before specimen collection. Cleanse specimen port with antiseptic swab, and then aspirate 5 mL of urine with a 21- to 25-gauge needle and syringe. Transfer urine to a sterile container.
  • Urinary Catheterization

  • Place female patient in lithotomy position or male patient in supine position. Using sterile technique, open the straight urinary catheterization kit and perform urinary catheterization. Place the retained urine in a sterile specimen container.
  • Suprapubic Aspiration

  • Place the patient in supine position. Cleanse the area with antiseptic, and drape with sterile drapes. A needle is inserted through the skin into the bladder. A syringe attached to the needle is used to aspirate the urine sample. The needle is then removed and a sterile dressing is applied to the site. Place the sterile sample in a sterile specimen container.
  • Do not collect urine from the pouch from a patient with a urinary diversion (e.g., ileal conduit). Instead, perform catheterization through the stoma.
  • General

  • Promptly transport the specimen to the laboratory for processing and analysis. If a delay in transport is expected, an aliquot of the specimen into a special tube containing a preservative is recommended. Urine transport tubes can be requested from the laboratory.


  • Inform the patient that a report of the results will be made available to the requesting HCP, who will discuss the results with the patient.
  • Instruct the patient to resume usual medication as directed by the HCP.
  • Instruct the patient to report symptoms such as pain related to tissue inflammation, pain or irritation during void, bladder spasms, or alterations in urinary elimination.
  • Observe for signs of inflammation if the specimen is obtained by suprapubic aspiration.
  • Administer antibiotic therapy as ordered. Remind the patient of the importance of completing the entire course of antibiotic therapy, even if signs and symptoms disappear before completion of therapy.
  • Nutritional Considerations: Instruct the patient to increase water consumption by drinking 8 to 12 glasses of water to assist in flushing the urinary tract. Instruct the patient to avoid alcohol, caffeine, and carbonated beverages, which can cause bladder irritation.
  • Prevention of UTIs includes increasing daily water consumption, urinating when urge occurs, wiping the perineal area from front to back after urination/defecation, and urinating immediately after intercourse. Prevention also includes maintaining the normal flora of the body. Patients should avoid using spermicidal creams with diaphragms or condoms (when recommended by an HCP), becoming constipated, douching, taking bubble baths, wearing tight-fitting garments, and using deodorizing feminine hygiene products that alter the body’s normal flora and increase susceptibility to UTIs.
  • Recognize anxiety related to test results. Discuss the implications of abnormal test results on the patient’s lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate.
  • Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Emphasize the importance of reporting continued signs and symptoms of the infection. Instruct patient on the proper technique for wiping the perineal area (front to back) after a bowel movement. Answer any questions or address any concerns voiced by the patient or family.
  • Depending on the results of this procedure, additional testing may be performed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

  • Related tests include CBC, CBC WBC count and differential, cystometry, cystoscopy, cystourethrography voiding, cytology urine, Gram stain, renogram, and UA.
  • Refer to the Genitourinary and Immune systems tables at the end of the book for related tests by body system.
Handbook of Laboratory and Diagnostic Tests, © 2013 Farlex and Partners
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