K35.3
K35.3 — Acute appendicitis with localized peritonitis
Non-billable headerICD-10-CM
K35.3 is a non-billable header ICD-10-CM code for acute appendicitis with localized peritonitis. It cannot be billed on its own: choose one of the more specific child codes below.
Other codes that can never be billed with K35.3
These codes carry an Excludes1 note pointing at K35.3. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading K35.3 alone.
- K37Unspecified appendicitis
Risk adjustment
K35.3 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.
Code to one of these instead K35.3
4 child codes. Green means billable.
- K35.30Acute appendicitis with localized peritonitis, without perforation or gangrene
- K35.31Acute appendicitis with localized peritonitis and gangrene, without perforation
- K35.32Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess
- K35.33Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess
Related codes at this level
Codes that share K35. If K35.3 is not quite right, the correct code is usually one of these.
Questions about K35.3
- Is K35.3 a billable ICD-10-CM code?
- No. K35.3 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
- Where does K35.3 sit in the tabular list?
- Diseases of the digestive system (K00-K95), in the block Diseases of appendix (K35-K38).