FAQs: Urinary Tract Infection (UTI) Events

Catheter-Associated Urinary Tract Infection [CAUTI] and Non-Catheter-Associated Urinary Tract Infection [UTI] and Other Urinary System Infection [USI]

Spinal cord injury, heavily sedated, or ventilated patients

Q1: My location cares for patients who may not be able to verbalize or sense suprapubic tenderness or costovertebral angle pain or tenderness, e.g., patients with spinal cord injury, heavily sedated or ventilated patients. How can I report CAUTI in these patients?

Surveillance criteria may not be equally sensitive for all patient populations. Patient populations in which the UTI criteria may not be as sensitive include spinal cord injury patients, those with brain injuries, and heavily sedated patients. NHSN constructed its Surveillance definitions to balance sensitivity and specificity along with feasibility. A set of criteria that covered every subpopulation with high specificity and sensitivity would be too complicated to employ consistently across different facilities. Simply follow the criteria as written in locations in which you are performing CAUTI surveillance.

Mechanical ventilation or sedation does not always mean that patients will not be able to verbalize pain. Facilities should always perform physical examination and assess patients for non-verbal communication of pain or tenderness.

100,000 CFU/ml included in more than 1 laboratory category

My lab offers culture counts that are:

  • 75k-100,000 CFU/ml
  • >100,000 CFU/ml

Q2. Can I use positive cultures reported as 75-100,000 CFU/ml to meet the UTI definition?

You must check with your laboratory to determine if they can identify whether at least 100,000 CFU/ml are identified in the urine culture, and if so to report it as ≥ 100,000 CFU/ml. Some laboratories have been able to clarify this.
If they cannot, and you cannot say for certain that a culture has at least 100,000 CFU/ml because the lab reported it as 75,000-100,000 CFU/ml, do not use that culture for NHSN UTI surveillance.

Mixed flora

Q3: If a urine culture is positive for 1 organism >100,000 CFU/ml and for mixed flora, is this an eligible urine culture results required for UTI?

No, this urine culture is not eligible for use in an NHSN UTI determination. Because “mixed flora”* implies that at least 2 organisms are present in addition to the identified organism, the urine culture does not meet the criteria for a positive urine culture with 2 organisms or less. Such a urine culture cannot be used to meet the NHSN UTI criteria. * The same is true for perineal flora, normal flora, and vaginal flora

Morphology determining what equates to > 2 organisms

Q4: If a urine culture result includes:

  • Ecoli #1>100,000 CFU/ml
  • Ecoli #2 > 10,000 CFU/ml
  • Staph Aureus> 100,000 CFU/ml, is this considered > 2 organisms?

No. NHSN surveillance identification of an organism to the genus level or the species level, for example Escherichia (genus) coli (species) or Enterococcus species is as far as you can get for reporting purposes. The E. coli #1 and #2 is considered one organism, similarly Enterococcus species #1 and Enterococcus species #2 would be considered one organism. Antimicrobial susceptibility results and colony morphology difference do not equate to a report of separate organisms. This urine culture result is not > 2 organisms and is an eligible specimen.

Multiple colony counts for the same organism

I have a final lab result for a patient in my possible CAUTI report:

  1. 50,000 to 100,000 colonies/mL Pseudomonas aeruginosa #1
  2. 50,000 to 100,000 colonies/mL Pseudomonas aeruginosa #2
  3. 10,000 to 50,000 colonies/mL Pseudomonas aeruginosa #3

Q5. Since these are the same organism, they would add up to 110K CFU/mL, would this be considered 1 organism of >100K and an acceptable culture to meet the UTI criteria?

Yes. When an organisms found in urine are identified to the same genus and species level but there is indication of different colony morphology or a different antibiogram (indicated by strain 1 or strain 2, colony A , colony B, for example), for purposes of NHSN UTI surveillance the organisms should be considered the same and if the sum total of the colony counts is ≥ 100,000 CFU/ml the culture result is eligible for use in meeting a UTI definition. If antibiograms are available and the sensitivities differ for the same organisms, always report the more resistant panel. Colony morphology, biotype, and antibiogram comparisons should not be used to differentiate organisms because laboratory testing capabilities and protocols vary between facilities.

Number of organisms in cultures

Q6. I have a patient that had a positive urine culture with 100,000 CFU/ml of E. coli and then, within the repeat infection time frame (RIT), another urine culture that had greater than 100,000 CFU/ml of K. pneumoniae and E. faecium. Can I use these cultures to meet the UTI criteria or, because there are more than 3 organisms in the UTI RIT, would they be excluded?

Do not add multiple cultures together. More than 2 organisms in a single urine culture suggests the possibility of contamination of the specimen. The same is not true for separate urine cultures with less than 3 organisms in each.

In this example the first culture would be eligible for a UTI. If no UTI was associated with that urine culture, then the second urine culture could be considered for UTI, since no previous UTI RIT was set and there were not more than 2 organisms in that urine culture.

Identifying single vs multiple UTIs

Q7: Is there a time period following the identification of a UTI during which another UTI cannot be reported?

Yes. This time period is called the Repeat Infection Timeframe (RIT). Please see the information on RIT found in  Chapter 2 “Identifying Healthcare-associated Infections pdf icon[PDF – 1 MB]” in the NHSN manual.

Patient reported fever

Q8: Can I use patient reported fever to meet CDC/NHSN UTI criteria for present on admission (POA)?

If the patient reports a fever > 38.0°C (or over 100.40 F), during the POA timeframe and within the IWP of a positive urine culture, this can be used to determine if the definition of a POA infection is met. A general report of “fever” by the patient, without an accompanying temperature measurement, may not be used.

UTI Symptom: dysuria

Q9: Is urinary retention the same as dysuria?

Urinary retention is not the same as dysuria and cannot be used to meet the UTI definition.

UTI Symptoms: urinary urgency, urinary frequency and dysuria

Q10: If a patient has a history of urinary urgency, urinary frequency or dysuria can another recognized cause be determined?

No, “with no other recognized cause” does not apply to these symptoms. In the presence of a positive urine culture which may have been collected as a differential diagnosis for suspicion of UTI it would be very rare that there is another associated cause for urinary urgency, urinary frequency and dysuria which are hallmark UTI symptoms.

Q11: Can these symptoms be used on the same day when the indwelling urinary catheter was removed and reinserted?

Yes. IF these symptoms occurred when the indwelling urinary catheter was not in place at the time of the symptom, it can be used as an element even on a day when the indwelling urinary catheter was in place for part of the day.

Costovertebral angle (CVA) pain or tenderness

Q12: Would NHSN accept low back pain to describe costovertebral pain?

Left or right lower back or flank pain is acceptable. Generalized “low back pain” in the medical record is not interpreted as CVA pain or tenderness, as there can be many causes of low back pain.

Suprapubic tenderness

Q13: Can abdominal pain be used to meet NHSN’s UTI symptom of suprapubic tenderness

There are many causes of abdominal pain and this symptom is too generalized to meet the localized UTI symptom of suprapubic tenderness. Low abdominal pain or bladder or pelvic discomfort are acceptable symptoms to meet NHSN’s UTI symptom of suprapubic tenderness.

“With No other recognized cause”

Q14: Would NHSN consider a patient complaint of low abdominal pain or a patient complaint of flank pain as being “other recognized cause” due to recent surgery or some other event/disease process thereby meeting “other recognized cause”?

Clinical decision about “with no other recognized cause” for the UTI signs/symptoms of suprapubic tenderness or costovertebral angle pain or tenderness should be made by the person performing NHSN UTI surveillance in your organization who has access to the entire medical record and clinical picture. Clinical judgment determination needs to be defended and backed up by medical record documentation and there should be clear rationale in the event the case is validated. General guidance: UTI signs/symptoms within the IWP of a positive urine culture would seem to indicate the symptom is a UTI symptom related to the positive urine culture; which may have been collected based on suspicion of UTI. To use “with no other recognized cause” it should be clear the symptom relates to that cause and is clearly differentiated from a UTI symptom.

Leg bags/attaching urometers

Q15: My facility changes indwelling urinary catheters from bed bags to leg bags so that our patients can attend physical therapy.


My ICU opens catheter systems to replace catheter bags with urometers. Should these be included in CAUTI surveillance since the system is not “closed”?

Yes. Both practices may increase the risk of UTI, and these patients should be included in CAUTI surveillance.


Q16: Are asymptomatic bacteremic urinary tract infections (ABUTIs) in patients in adult and pediatric intensive care units (ICUs) or medical, surgical, or medical/surgical wards included in the reporting requirements for CMS’s Hospital Inpatient Quality Reporting Program?

Only catheter-associated UTI data (both ABUTI and SUTI) are shared with CMS. Keep in mind that ABUTI may occur in patients with or without an indwelling urinary catheter. Therefore, if a patient in one of these locations has an ABUTI and an indwelling urinary catheter within the timeframe to meet the device-associated rule; this is a CAUTI and is reportable to CMS if CAUTI reporting in the location is included in your monthly reporting plan.

Device attribution

Q17: If a patient with a CAUTI had multiple catheters placed/removed during the IWP, to which catheter should I attribute the CAUTI?

NHSN surveillance is aimed at identifying risk to the patient that is the result of device use in general, not risk from a specific device. NHSN does not allow for attribution to a specific device when entering a UTI event. You should attribute the UTI to the inpatient location where the patient was assigned on the DOE.

Patients with colovesical fistula

Q18: Are patients with colovesical fistula excluded from meeting the NHSN UTI definition?

No. Patients with colovesical, enterovesical, or rectovesical fistulae are not excluded from meeting the NHSN UTI definition. NHSN surveillance for infection is aimed at identifying risk to the patient that is the result of device use in general, not aimed at a specific device. An indwelling urinary catheter in place puts the patient at risk and, therefore, is included in CAUTI surveillance.

The purpose of submitting a urine specimen for culture is to determine infection. The NHSN definitions currently account for contamination of urine specimens. NSHN excludes specimens with a culture results of more than two organisms (polymicrobial) for use in meeting UTI definitions.

Secondary BSI and associated urine colony count

Q19: When the colony count of an eligible UTI pathogen does not meet the requirement for use in meeting the UTI definition, can I still use that pathogen to attribute a BSI with matching pathogen to the UTI event?  For example, assuming a UTI definition is met using a urine culture with > 100,000 CFU/ml E. coli and 50,000 CFU/ml MRSA, can a BSI with MRSA only be attributed as a secondary BSI?

No. Only the E. coli has a colony count eligible for use in meeting a UTI criteria. Scenario 1 of the Secondary BSI guide (Appendix B of the BSI protocol pdf icon[PDF – 1 MB]) states: At least one organism from the blood specimen must match an organism identified from the site-specific infection, in this case the urine, that is used as an element to meet the NHSN site-specific infection criterion. The 50,000 CFU/ml MRSA is not used as an element in the UTI definition. In this example the BSI with MRSA only cannot be attributed as secondary to the UTI event. Additionally, the blood specimen must have a collection date within the UTI secondary BSI attribution period.

What information is needed to assist with UTI determination?

Q20: For NHSN to assist with a UTI case determination please send the following information to nhsn@cdc.gov:

  • Date of Admission
  • Date(s) of indwelling urinary catheter insertion/removal if applicable
  • Age of patient, Collection date(s) and results of urine cultures including colony count
  • Collection date(s) and results of any positive blood cultures
  • Date(s) and types of UTI signs/symptoms such as fever >38.0°C, suprapubic tenderness*, costovertebral angle pain or tenderness*, urinary urgency^, urinary frequency^, dysuria^

* With no other recognized cause

^ These symptoms cannot be used when catheter is in place. An indwelling urinary catheter in place could cause patient complaints of “frequency” “urgency” or “dysuria”.

Note: Please do not send Personal Identifiable Information through the NHSN email system.