Q&A: Principal diagnosis assignment for UTI versus encephalopathy

Q: How should the diagnosis of urinary tract infection (UTI) and encephalopathy be sequenced, specifically which diagnosis should be the principal? If physician documentation indicates that the patient came in with confusion, can encephalopathy be assigned as the principal diagnosis if it is due to the UTI and no other contributing issues are present?

A: Assigning the UTI as the principal diagnosis makes the claim more vulnerable to denial than the encephalopathy does. If you look at the big picture, a UTI does not support inpatient care. Additionally, there is no coding rule that requires the UTI to be coded as the principal diagnosis because it is not part of an etiology/manifestation pair. According to the Uniform Hospital Discharge Data Set (UHDDS) definition of the principal diagnosis, it is the condition (after study) that occasioned the admission.

The inclusion of the term “after study” is often what throws off accurate principal diagnosis assignments, because people don’t look at the totality of the coding guidelines. At times symptoms present at the time of admission require further “study” in order for the physician to find a definitive diagnosis.

Symptoms may be reported when no other definitive diagnosis can be identified, but this this leads to assignment of a lower-weighted MS-DRG, less specificity in assignment, and vague medical record overall. So, the preference is to avoid reporting symptoms as a principal diagnosis.

For example, the provider often describes encephalopathy instead of diagnosing it, documenting the patient as having altered mental status. If the patient has encephalopathy, they usually need inpatient care, not just supportive care, because the goal is to stop the progression of the encephalopathy by finding and treating the cause.

When looking at the record, think about the patient’s continuum of care. Ask yourself, at what point is the patient safe for discharge? In this case, would it be when the physician treats the encephalopathy or the UTI? Clinically speaking, this patient would be safe to discharge when he or she returns to baseline in mental functioning, not when the UTI is resolved.

A UTI (even a complicated one) can be treated in the outpatient setting. Also, look at the totality of the record: Was the focus of the treatment the “altered mental status” (was a CT scan performed, etc.) or was it on a UTI?

Not every patient with a UTI has encephalopathy. However, if they are sick enough to need inpatient care, they likely have more going on.

Encephalopathy also isn’t as big of an audit target as UTIs. Yes, auditors do deny encephalopathy claims since it is an MCC—but so is severe malnutrition, acute respiratory failure, etc. Think about what type of claim is usually more vulnerable.

When the UTI is the principal diagnosis and encephalopathy is the MCC, there is only one MCC in the record. When encephalopathy is the principal diagnosis, the UTI can be added as a CC.

When the encephalopathy is a principal diagnosis, auditor denials are not the issue; the real concern is with the documentation not supporting it as a reportable condition. Think of encephalopathy as on a continuum with acute confusion, delirium, and encephalopathy, because everything isn’t encephalopathy. It can, oftentimes, only be accurately diagnosed when working backward asking, “When does the patient return to baseline,” and “What treatment was necessary?”

It would be interesting to find out if the infection control team supports the diagnosis of a UTI, as, often, the UTI is a process of elimination diagnosis because the urine is “dirty.” But it doesn’t always clinically meet the definition of a UTI by Centers for Disease Control guidelines. If that is the case, what is the provider really treating? They could be treating the altered mental status. However, that is only a symptom, and the goal of CDI is to find a diagnosis associated with that symptom. That diagnosis could be acute confusion, delirium or, in some cases, encephalopathy.

Editor’s Note:Cheryl Ericson, MS, RN, CCDS, CDIP, AHIMA-approved ICD-10-CM/PCS trainer, associate director for education at ACDIS and CDI education director at HCPro in Danvers, Massachusetts, contributed to this post.