K65.0 Generalized (acute) peritonitis

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Applicable to

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

Applies from K65 Peritonitis

Excludes1 (never code together)

• 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 code

• code (B95-B97), to identify infectious agent, if known

Code also

• if applicable diverticular disease of intestine (K57.-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 78 — Intestinal Obstruction/Perforation
• CMS-HCC V22: HCC 33 — Intestinal Obstruction/Perforation
• ESRD V24: HCC 33

MS-DRG index

Defines the logic of DRG(s) 371-373 in MDC 06.

Approximate ICD-9-CM (GEMs)

• 567.21 Peritonitis (acute) generalized (approximate)
• 567.29 Other suppurative peritonitis (approximate)

Code annotations containing back-references to K65.0

Back-references to K65

• Code Also: K57 Diverticular disease of intestine ("if applicable peritonitis K65.-")

Diagnosis Index entries for K65.0

• Cellulitis (diffuse) (phlegmonous) (septic) (suppurative) › pelvis, pelvic (chronic) › male
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › acute (generalized)
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › diaphragmatic
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › diffuse
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › disseminated
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › eosinophilic › acute
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › fibropurulent
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › general (ized)
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › pancreatic
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › pelvic › male
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › purulent
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › septic
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › subdiaphragmatic
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › subphrenic
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › suppurative
• Rupture, ruptured › cecum (with peritonitis)
• Suppuration, suppurative › pelvis, pelvic › male

Nearby codes

• K65 Peritonitis
• K65.0 Generalized (acute) peritonitis (this code)
• K65.1 Peritoneal abscess
• K65.2 Spontaneous bacterial peritonitis
• K65.3 Choleperitonitis
• K65.4 Sclerosing mesenteritis
• K65.8 Other peritonitis