ICD-10 K21.01
Billable / Specific MCCGastro-esophageal reflux disease with esophagitis, with bleeding
About ICD-10-CM K21.01
ICD-10-CM code K21.01 represents Gastro-esophageal reflux disease with esophagitis, with bleeding. This is a billable/specific code in the Digestive System chapter (block K21). The 2026 edition of ICD-10-CM K21.01 became effective on October 1, 2025.
Coding Tips for K21.01
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
K21.01 is designated MCC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-MCC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag MCC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Inpatient DRG Impact, MCC
codes Gastro-esophageal reflux disease with esophagitis, with bleeding. As a Major Complication/Comorbidity (MCC), this can shift the DRG assignment to a higher-weighted category, substantial reimbursement impact.
Medicare LCD Coverage for K21.01
Local Coverage Determinations (LCDs) from CMS MACs that list K21.01 as a covered diagnosis.
Showing top 10 of 324 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing K21.01.
5 Medicare
1 Aetna
CPT Codes Commonly Billed with K21.01
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Codes Adjacent To K21.01
Other codes in section K20-K31 (Diseases of esophagus, stomach and duodenum).
ICD-10 K21.01, Billing FAQ
Is ICD-10 code K21.01 billable? +
Yes, K21.01 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
Is K21.01 a CC or MCC for inpatient DRG? +
Yes, this code is designated as MCC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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