Coding and coverage · ICD-10-CM

K65

K65.0 Generalized (acute) peritonitis

BillableCMS-HCC V28: HCC 78Chapter 11
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Instructional notes

Chapter 11

Excludes2Not included here: the patient may have both; report both when both are present.
  • 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)

K65

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • 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.-)
Use additional codeAdd a second code for the full picture.
  • code (B95-B97), to identify infectious agent, if known
Code also
  • if applicable diverticular disease of intestine (K57.-)

This code

Inclusion terms
  • Pelvic peritonitis (acute), male
  • Subphrenic peritonitis (acute)
  • Suppurative peritonitis (acute)

Chapter 11: Diseases of the digestive system · K65-K6A Diseases of peritoneum, retroperitoneum and pelvis (K65-K6A)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.