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K35.210

K35.210Acute appendicitis with generalized peritonitis, without perforation, with abscess

Billable / specific codeICD-10-CM

K35.210 is a billable, specific ICD-10-CM code for acute appendicitis with generalized peritonitis, without perforation, with abscess. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • (Acute) appendicitis with generalized peritonitis without rupture or perforation of appendix, with abscess

Risk adjustment

K35.210 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

K35.210 is named in 6 Medicare coverage policies 6 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A55336Billing and Coding: Retroperitoneal Ultrasound
  • A56421Billing and Coding: CT of the Abdomen and Pelvis
  • A58710Billing and Coding: MolDX: Molecular Syndromic Panels for Infectious Disease Pathogen Identification Testing
  • A58720Billing and Coding: MolDX: Molecular Syndromic Panels for Infectious Disease Pathogen Identification Testing

How K35.210 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to K35.210.

  • Appendicitiswithperitonitis NECgeneralizedwithabscesswithout perforation or rupture
  • Appendicitisacutewithperitonitis NECgeneralizedwithabscesswithout perforation or rupture

Related codes at this level

Codes that share K35.21. If K35.210 is not quite right, the correct code is usually one of these.

Questions about K35.210

Is K35.210 a billable ICD-10-CM code?
Yes. K35.210 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does K35.210 sit in the tabular list?
Diseases of the digestive system (K00-K95), in the block Diseases of appendix (K35-K38).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.