Alphabetic Index FY2027

K35.3

Acute appendicitis with localized peritonitis

FY2027Chapter 11: Diseases of the digestive system/K35–K38 Diseases of appendix

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

K35.3 is a non-billable ICD-10-CM code header for acute appendicitis with localized peritonitis. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are K35.30 Acute appendicitis with localized peritonitis, without perforation or gangrene; K35.31 Acute appendicitis with localized peritonitis and gangrene, without perforation; K35.32 Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess and K35.33 Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess. Its coding notes include 8 Excludes2 entries.

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (8 notes)
Inherited from Chapter 11 Diseases of the digestive system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

More specific codes under K35.3 4