Editing Urinary Tract Infections (section)

==== Urine collection ====
* '''Voided and catheterized specimens'''
** '''Males'''
*** '''In circumcised males, voided specimens require no preparation. For males who are not circumcised, the foreskin should be retracted and the glans penis washed with soap and then rinsed with water before specimen collection.'''
*** '''The first 10 mL of urine (representative of the urethra) and a midstream specimen (representative of the bladder) should be obtained.'''
*** '''Prostatic fluid is obtained by performing digital prostatic massage''' and collecting the expressed prostatic fluid on a glass slide. In addition, '''collection of the first 10 mL of voided urine after massage will reflect the prostatic fluid added to the urethral specimen.'''
*** Catheterization of a male patient for urine culture is not indicated unless the patient cannot urinate.
** '''Females'''
*** '''In females, contamination of a midstream urine specimen with introital bacteria and WBCs is common, particularly when the woman has difficulty spreading and maintaining separation of the labia. Therefore, females should be instructed to spread the labia, wash and cleanse the periurethral area with moist gauze, and then collect a midstream urine specimen.'''
**** '''Cleansing with antiseptics is not recommended''' because they may contaminate the voided specimen and provide a false-negative urine culture.
*** '''The voided specimen is contaminated if it shows evidence of vaginal epithelial cells and lactobacilli on urinalysis,''' and a catheterized specimen should be collected.
* '''Suprapubic aspiration'''
** '''Advantage: highly accurate'''
** '''Disadvantages:''' '''some morbidity'''
** '''Limited clinical usefulness''' except for a patient who cannot urinate on command such as patients with spinal cord injuries and newborns
** Steps to perform procedure available in CW11 page 250
* '''Bag specimens'''
** '''Unreliable and unacceptable for diagnosis of UTI in high-risk populations and infants'''.
*** '''Generally, if a UTI is suspected in a child who is not yet toilet trained, only a catheterized or needle-aspirated specimen is acceptable for diagnosis''' because bagged urinary specimens have an unacceptably high false-positive rate.
**** Under special collection circumstances when the perineum is cleaned well and the bag removed and processed promptly after voiding, a bagged specimen or even a diaper specimen that shows no growth is useful in eliminating bacteriuria as a diagnosis.