In inpatient MS-DRG grouping, what is the role of a documented secondary diagnosis such as acute kidney injury?
Select an answer to reveal the explanation.
Short Explanation
A solid secondary like acute kidney injury can bump the stay into a higher severity DRG—if that code sits on the CC or MCC list for the case. It is not automatic principal diagnosis magic; it is severity logic on top of the principal.
Full Explanation
Under IPPS MS-DRG methodology, secondary diagnoses on the CMS CC or MCC lists can change the severity tier (no CC/MCC, with CC, or with MCC) when they are valid for the principal diagnosis and meet reporting criteria. Acute kidney injury is a common example of a condition that may group as a CC or MCC depending on the coded value and exclusion logic. It does not automatically become principal diagnosis solely because labs worsened.