Q&A: Coding and querying metabolic encephalopathy

Q: I would like to add encephalopathy due to urinary tract infection (UTI) to our quick coding tips. Coding Clinic instructs coding professionals to code as G93.49, other encephalopathy, which is now a CC. The CDI specialists want to query for metabolic encephalopathy, which they say this scenario fits (which is an MCC). What do you think about that? I think due to the Coding Clinic and the difference in payment, this could be an area that auditors scrutinize.

A: When considering metabolic encephalopathy, you have to be able to demonstrate within the record what the nature of the metabolic disruption is, and it would have to be more just the existence of a UTI. If there are no other metabolic disruptions apparent in the record with a known mechanism of causing encephalopathy, coding professionals should follow Coding Clinic and assign G93.49, other encephalopathy.

On the clinical side of things, when you have a UTI with a typical systemic inflammatory response syndrome response, the mechanism of the encephalopathy is the release of inflammatory proteins (e.g., cytokines) into the bloodstream that cause a secondary metabolic disruption via invoking a number of known mechanisms. It’s a related mechanism to encephalopathy in a septic patient, which by the way, does code to metabolic encephalopathy.

I am not sure if the authors of the Coding Clinic on this issue even considered the full pathophysiology, but I think Coding Clinic is clear that in the absence of any other metabolic problems, G93.49 is the code to use.

Of course, code assignment and queries are two separate things; I am not sure if I would be comfortable placing a query for metabolic encephalopathy with no other indicators than a UTI in the presence of altered mental status. If the patient has other coexisting electrolyte, acid base, oxygenation, glucose, or organ dysfunctions, etc., I think a query for metabolic encephalopathy is reasonable.

If, however, a doctor wants to name an encephalopathy as metabolic based on an infectious process, I wouldn’t try to talk him or her out of it. However, I would invoke the recent Coding Clinic that states that, in such a case, a CDI professional should ask the physician to document their rationale. Additionally, the physician should give a sentence or two explaining their choice of metabolic encephalopathy when it is only due to a localized infection and document that the metabolic encephalopathy is being mediated by metabolic disruptions because of inflammatory mechanisms.

Editor’s note: Allen Frady, RN, BSN, CCDS, CCS, CRC, CDI education specialist for HCPro in Middleton, Massachusetts, answered this question. Contact him at AFrady@hcpro.com. For information regarding CDI Boot Camps, click here.