K65.3

Choleperitonitis

FY2027Chapter 11: Diseases of the digestive system/K65–K6A Diseases of peritoneum, retroperitoneum and pelvis

BillableComplete code, valid to report

K65.3 (also written K653) is a billable ICD-10-CM diagnosis code for choleperitonitis. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 7 codes in category K65 (Peritonitis). The Alphabetic Index lists it under 3 entries. Its coding notes include a Use additional code instruction, a Code also instruction, 17 Excludes1 entries and 8 Excludes2 entries.

Use additional code

Add the listed code as a secondary code, if known.

Inherited from K65 Peritonitis
  • code (B95-B97), to identify infectious agent, if known

Code also

Two codes may be needed to describe the condition. This note gives no sequencing order.

Inherited from K65 Peritonitis
  • if applicable diverticular disease of intestine (K57.-)

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from K65 Peritonitis
  • acute appendicitis with generalized peritonitis (K35.2-)
  • aseptic peritonitis (T81.6)
  • benign paroxysmal peritonitis (E85.0)
  • chemical peritonitis (T81.6)
  • gonococcal peritonitis (A54.85)
  • neonatal peritonitis (P78.0-P78.1)
  • pelvic peritonitis, female (N73.3-N73.5)
  • periodic familial peritonitis (E85.0)
  • peritonitis due to talc or other foreign substance (T81.6)
  • peritonitis in chlamydia (A74.81)
  • peritonitis in diphtheria (A36.89)
  • peritonitis in syphilis (late) (A52.74)
  • peritonitis in tuberculosis (A18.31)
  • peritonitis with or following abortion or ectopic or molar pregnancy (O00-O07, O08.0)
  • peritonitis with or following appendicitis (K35.-)
  • puerperal peritonitis (O85)
  • retroperitoneal infections (K68.-)

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)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Gastrointestinal tract and Genitourinary system clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

Hospital MCC

Counts as a major complication or comorbidity (MCC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 25 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

Inclusion terms

Conditions classified to this code.

This code
  • Peritonitis due to bile

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 3 entries