CPP-047_inpatient-drg-validation_v3.1.md

# CPP-047 — Inpatient DRG validation: complications and comorbidities **Version 3.1 · Effective 1 January 2026 · Supersedes v3.0** Owner: Facility Audit Policy Applies to: Medicare Advantage · Medicaid — all states External basis: CMS MS-DRG Definitions Manual v43 · ICD-10-CM Official Guidelines for Coding and Reporting ## 1. Purpose An inpatient admission is paid on a diagnosis-related group. The severity tier of that group, and therefore the payment, frequently rests on a single reported secondary diagnosis. This policy governs what such a diagnosis must be supported by before it is allowed to raise the tier. ## 2. What changed in version 3.1 Version 3.0 required clinical indicators in general terms. Version 3.1 names the threshold for the two conditions that most often carry an admission up a tier: 1. Acute kidney injury reported as a major complication or comorbidity now requires creatinine values meeting a KDIGO stage against a documented baseline. 2. Sepsis reported

dmission up a tier: 1. Acute kidney injury reported as a major complication or comorbidity now requires creatinine values meeting a KDIGO stage against a documented baseline. 2. Sepsis reported as a major complication or comorbidity now requires documented organ dysfunction.

## 3. Criteria ### 3.1 Clinical validation A reported major complication or comorbidity (MCC), or complication or comorbidity (CC), must be supported by clinical indicators, treatment, or monitoring recorded during the admission. A diagnosis that appears only in the discharge summary or only on the coding abstract, with nothing in the record that corresponds to it, is not validated. ### 3.2 Acute kidney injury Acute kidney injury reported as an MCC requires serum creatinine meeting KDIGO stage 1 or above against a documented baseline: - a rise of 0.3 mg/dL or more within 48 hours; or - a rise to 1.5 times the baseline or more within seven days; or - urine output below 0.5 mL/kg/h for six hours. A peak creatinine that does not meet a stage against the baseline recorded for that patient does not support the diagnosis, whatever the absolute value. ### 3.3 Sepsis Sepsis reported as an MCC requires documented organ dysfunction. Infection alone, or a systemic inflammatory response

ient does not support the diagnosis, whatever the absolute value. ### 3.3 Sepsis Sepsis reported as an MCC requires documented organ dysfunction. Infection alone, or a systemic inflammatory response without organ dysfunction, does not support the diagnosis at the MCC tier. ### 3.4 Repricing Where the reported MCC is not substantiated, the admission reprices to the DRG that results when that diagnosis is excluded — ordinarily the group one severity tier down. The admission is not denied, and the principal diagnosis is not disturbed.

## 4. Recovery The recoverable amount is the difference between the relative weight of the billed DRG and the relative weight of the corrected DRG, multiplied by the contracted base rate for the facility. recovery = (billed weight - corrected weight) x base rate Both weights come from the MS-DRG Definitions Manual version in effect on the date of admission. The arithmetic is shown to the provider in full. ## 5. Relationship to present-on-admission reporting A diagnosis that is clinically substantiated but reported as not present on admission is governed by CPP-052 rather than by this policy. The two findings are distinct: this policy asks whether the condition was there, CPP-052 asks whether it arrived before the patient did. ## 6. Provider dispute A provider disputing a finding under this policy may submit the complete inpatient record. Where the record contains indicators meeting section 3.2 or 3.3, the finding is withdrawn and the original DRG stands.