K35.201 — Acute appendicitis with generalized peritonitis, with perforation, without abscess
K35.201 is a billable, specific ICD-10-CM code for acute appendicitis with generalized peritonitis, with perforation, without abscess. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Appendicitis (acute) with generalized (diffuse) peritonitis following rupture or perforation of appendix NOS
Risk adjustment
K35.201 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
K35.201 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 K35.201 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 K35.201.
- Appendicitis›with›peritonitis NEC›generalized›following rupture or perforation of appendix NOS
- Appendicitis›acute›with›peritonitis NEC›generalized›following rupture or perforation of appendix NOS
- Appendicitis›with›peritonitis NEC›generalized›with›perforation or rupture
- Appendicitis›acute›with›peritonitis NEC›generalized›with›perforation or rupture
Related codes at this level
Codes that share K35.20. If K35.201 is not quite right, the correct code is usually one of these.
Questions about K35.201
- Is K35.201 a billable ICD-10-CM code?
- Yes. K35.201 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does K35.201 sit in the tabular list?
- Diseases of the digestive system (K00-K95), in the block Diseases of appendix (K35-K38).