ICD-10 K35.211
Billable / Specific MCCAcute appendicitis with generalized peritonitis, with perforation and abscess
About ICD-10-CM K35.211
ICD-10-CM code K35.211 represents Acute appendicitis with generalized peritonitis, with perforation and abscess. This is a billable/specific code in the Digestive System chapter (block K35). The 2026 edition of ICD-10-CM K35.211 became effective on October 1, 2025.
Coding Tips for K35.211
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
K35.211 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.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under K35.211. Per CMS ICD-10-CM Tabular 2026.
- Appendicitis (acute) with generalized (diffuse) peritonitis following rupture or perforation of appendix, with abscess
Inpatient DRG Impact, MCC
codes Acute appendicitis with generalized peritonitis, with perforation and abscess. As a Major Complication/Comorbidity (MCC), this can shift the DRG assignment to a higher-weighted category, substantial reimbursement impact.
Medicare LCD Coverage for K35.211
Local Coverage Determinations (LCDs) from CMS MACs that list K35.211 as a covered diagnosis.
Showing top 10 of 549 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing K35.211.
5 Medicare
CPT Codes Commonly Billed with K35.211
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 K35.211
Other codes in section K35-K38 (Diseases of appendix).
ICD-10 K35.211, Billing FAQ
Is ICD-10 code K35.211 billable? +
Yes, K35.211 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to K35.211? +
ICD-10 K35.211 includes: Appendicitis (acute) with generalized (diffuse) peritonitis following rupture or perforation of appendix, with abscess.
Is K35.211 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 June 1, 2026.
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