K35.33 Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess

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

Applicable to

• (Acute) appendicitis with (peritoneal) abscess NOS
• Ruptured appendix with localized peritonitis and abscess

MS-DRG index

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

Code annotations containing back-references to K35.33

Back-references to K35.3

• Type 1 Excludes: K37 Unspecified appendicitis ("unspecified appendicitis with peritonitis (K35.2-, K35.3-)")
• Type 2 Excludes: K63.0 Abscess of intestine ("abscess of appendix (K35.3-)")
• Type 2 Excludes: K63.1 Perforation of intestine (nontraumatic) ("perforation (nontraumatic) of appendix (K35.2-, K35.3-)")

Back-references to K35

• Type 1 Excludes: K65 Peritonitis ("peritonitis with or following appendicitis (K35.-)")

Diagnosis Index entries for K35.33

• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › appendix
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › cecum
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › ileocecal
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › iliac (region) › fossa
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › periappendicular
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › pericecal
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › peritoneum, peritoneal (perforated) (ruptured) › with appendicitis
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › perityphlic
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › postcecal
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › subcecal
• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › vermiform appendix
• Appendicitis (pneumococcal) (retrocecal) › with › peritoneal abscess
• Appendicitis (pneumococcal) (retrocecal) › with › peritonitis NEC
• Appendicitis (pneumococcal) (retrocecal) › with › peritonitis NEC › localized › with › perforation › and abscess
• Appendicitis (pneumococcal) (retrocecal) › acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative) › with › peritoneal abscess
• Appendicitis (pneumococcal) (retrocecal) › acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative) › with › peritonitis NEC
• Appendicitis (pneumococcal) (retrocecal) › acute (catarrhal) (fulminating) (obstructive) (retrocecal) (suppurative) › with › peritonitis NEC › localized › with › perforation › and abscess
• Rupture, ruptured › cecum (with peritonitis) › with peritoneal abscess

Nearby codes

• K35.219 Acute appendicitis with generalized peritonitis, with abscess, unspecified as to perforation
• K35.3 Acute appendicitis with localized peritonitis
• K35.30 Acute appendicitis with localized peritonitis, without perforation or gangrene
• K35.31 Acute appendicitis with localized peritonitis and gangrene, without perforation
• K35.32 Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess
• K35.33 Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess (this code)
• K35.8 Other and unspecified acute appendicitis
• K35.80 Unspecified acute appendicitis
• K35.89 Other acute appendicitis
• K35.890 Other acute appendicitis without perforation or gangrene
• K35.891 Other acute appendicitis without perforation, with gangrene