ICD-10-CM
ICD-10 code for Appendicitis (pneumococcal) (retrocecal) acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative): K35.80
The ICD-10-CM index points "Appendicitis (pneumococcal) (retrocecal) acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative)" to K35.80, Unspecified acute appendicitis. K35.80 is a billable code.
Source: CDC ICD-10-CM FY2027 Alphabetic Index file dated June 16, 2026. Publisher page
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Index subterms
A header groups codes and is not billed. A billable code is one you can report.
More specific codes in K35
A header groups codes and is not billed. A billable code is one you can report.
- K35Acute appendicitisHeader
- K35.2Acute appendicitis with generalized peritonitisHeader
- K35.20Acute appendicitis with generalized peritonitis, without abscessHeader
- K35.200Acute appendicitis with generalized peritonitis, without perforation or abscessBillable
- K35.201Acute appendicitis with generalized peritonitis, with perforation, without abscessBillable
- K35.209Acute appendicitis with generalized peritonitis, without abscess, unspecified as to perforationBillable
- K35.21Acute appendicitis with generalized peritonitis, with abscessHeader
- K35.210Acute appendicitis with generalized peritonitis, without perforation, with abscessBillable
- K35.211Acute appendicitis with generalized peritonitis, with perforation and abscessBillable
- K35.219Acute appendicitis with generalized peritonitis, with abscess, unspecified as to perforationBillable
- K35.3Acute appendicitis with localized peritonitisHeader
- K35.30Acute appendicitis with localized peritonitis, without perforation or gangreneBillable
- K35.31Acute appendicitis with localized peritonitis and gangrene, without perforationBillable
- K35.32Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscessBillable
- K35.33Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscessBillable
- K35.8Other and unspecified acute appendicitisHeader
- K35.80Unspecified acute appendicitisBillable
- K35.89Other acute appendicitisHeader
- K35.890Other acute appendicitis without perforation or gangreneBillable
- K35.891Other acute appendicitis without perforation, with gangreneBillable
Related conditions
Related pages
- K35.80 code detailsNotes, nearby codes, CMS-HCC group
- Category K35Every code under it
- Chapter 11Diseases of the digestive system
- ICD-10 codes by conditionA to Z
- Check a list of ICD-10 codes
- Denial code CO-11Diagnosis does not support the procedure
- Denial code CO-146Diagnosis invalid for the date of service
- HCPCS Level II code lookup
Questions
What is the ICD-10 code for Appendicitis (pneumococcal) (retrocecal) acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative)?
The ICD-10-CM index points "Appendicitis (pneumococcal) (retrocecal) acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative)" to K35.80, Unspecified acute appendicitis. K35.80 is a billable code.
Is K35.80 billable?
Yes. K35.80 is a billable code in the FY2027 ICD-10-CM file. Use a more specific code when the record documents one.
What chapter is K35.80 in?
Chapter 11. Diseases of the digestive system.
When do ICD-10-CM codes change?
Every October 1, with the new fiscal year file. Some years add April 1 updates. This page uses the FY2027 file, effective October 1, 2026.