All ICD10 Codes
K65Non-billable

Peritonitis

Diseases of the Digestive System·Diseases of peritoneum and retroperitoneum (K65-K68)·category·FY 2026

Use a more specific code (7 billable)
K65.0Generalized (acute) peritonitisK65.1Peritoneal abscessK65.2Spontaneous bacterial peritonitisK65.3CholeperitonitisK65.4Sclerosing mesenteritisK65.8Other peritonitisK65.9Peritonitis, unspecified

CH11 Parent Instructions

Excludes2(Not included here. Code separately if applicable.)
  • 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)

Instructional Notes

Excludes1(Not coded here. Use a different code.)
  • 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.-)
Code Also
  • if applicable diverticular disease of intestine (K57.-)
Use Additional Code
  • code (B95-B97), to identify infectious agent, if known

Clinical Hierarchy

BillableHas subcodes
CH11Diseases of the digestive system (K00-K95)
K65-K68Diseases of peritoneum and retroperitoneum (K65-K68)
K65PeritonitisNot billable
K65.0Generalized (acute) peritonitisBillable
K65.1Peritoneal abscessBillable
K65.2Spontaneous bacterial peritonitisBillable
K65.3CholeperitonitisBillable
K65.4Sclerosing mesenteritisBillable
K65.8Other peritonitisBillable
K65.9Peritonitis, unspecifiedBillable

MS-DRG Classification

2026

No direct MS-DRG triggers identified.