CAUTI, a tale of two contexts

Confusion abounds over the diagnosis and documentation of catheter-associated urinary tract infections.

According to the National Healthcare Safety Network (NHSN), urinary tract infections (UTIs) were the fifth most common health care-associated infection in 2015, virtually all due to instrumentation of the urinary tract. About 12% to 15% of adult inpatients will have an indwelling urinary catheter at some point during their hospitalization. Each day the catheter remains in place increases the risk of UTI, with its associated complications, mortality, length of stay, and cost.

Image by Getty Images
Image by Getty Images

Catheter-associated urinary tract infections (CAUTIs) are considered significant, preventable inpatient complications of care. However, confusion abounds over the diagnosis, documentation, coding, and classification as a complication of care. In truth, the term CAUTI describes two separate clinical circumstances, one a diagnosis made by a clinician, the other a quality case definition from the CDC.

The clinical diagnosis of UTI is usually straightforward based on urinary culture results. Sometimes it is made without a confirmatory culture result, just based on symptoms and urinalysis results. When the diagnosis is documented by a clinician in the record, it is coded and submitted on a claim for payment, thereby entering the national health care database.

Whenever a urinary catheter is present in a patient with UTI, the question arises whether the catheter caused the infection. This determination is made by the clinician. If the UTI is attributed to the catheter, a code from series T83.51 (infection and inflammatory reaction due to urinary catheter) is sequenced before the UTI code. The specific code depends on the type of catheter involved.

For clinical/coding purposes, the diagnosis may be considered a complication of care if the UTI was not present on admission. The CMS Hospital Value-Based Purchasing Program (VBP) uses the coding/claims-based data in its hospital-acquired UTI safety measure.

The CDC case definition for symptomatic CAUTI in adults is completely different. In this case, CAUTI is defined by objective criteria abstracted from the medical record by quality nurses. It does not depend in any way on a clinician's diagnosis or documentation. In this context, a symptomatic CAUTI is defined by the finding of all the following:

1. An indwelling urinary catheter in place for more than two consecutive calendar days as an inpatient, with the catheter either present on the day of the event or removed the day before.

2. At least one of the following signs or symptoms:

  • Fever (temperature >38.0 °C or 100.4 °F)
  • Suprapubic tenderness (without other identifiable cause)
  • Costovertebral angle pain or tenderness (without other identifiable cause)
  • Urinary urgency (not used while catheter is in place)
  • Urinary frequency (not used while catheter is in place)
  • Dysuria (not used while catheter is in place)

3. Positive urine culture, specifically no more than two organisms, at least one of which is present in greater than 105 colony-forming units/mL.

The “event” is the first occurrence of either a positive culture or symptoms. All three elements must occur within a time frame specified by the CDC. The CMS Hospital-Acquired Condition Reduction Program uses this objective, abstracted case definition of CAUTI in its assessments.

Controversy sometimes arises when there is a mismatch between the abstracted and the clinical/coded CAUTI result. However, these two entirely different meanings and definitions of CAUTI in two different contexts do not match and are not intended to. A clinician may diagnose a CAUTI in a case that does not meet the CDC criteria, and it should then be coded on the hospital's claim. The abstracted quality case definition from the CDC has nothing to do with clinician documentation or coding. Don't get hung up over a mismatch between quality abstracting and coding of CAUTI.