K65.1
Peritoneal abscess
Billable FY2026 2025-10-01 → 2026-09-30
Exclusions 25 never code together
K65code
Excludes1
- acute appendicitis with generalized peritonitis (K35.2-)K35.2-
- aseptic peritonitis (T81.6)T81.6
- benign paroxysmal peritonitis (E85.0)E85.0
- chemical peritonitis (T81.6)T81.6
- gonococcal peritonitis (A54.85)A54.85
- neonatal peritonitis (P78.0-P78.1)P78.0-P78.1
- pelvic peritonitis, female (N73.3-N73.5)N73.3-N73.5
- periodic familial peritonitis (E85.0)E85.0
- peritonitis due to talc or other foreign substance (T81.6)T81.6
- peritonitis in chlamydia (A74.81)A74.81
- peritonitis in diphtheria (A36.89)A36.89
- peritonitis in syphilis (late) (A52.74)A52.74
- peritonitis in tuberculosis (A18.31)A18.31
- peritonitis with or following abortion or ectopic or molar pregnancy (O00-O07, O08.0)O00-O07O08.0
- peritonitis with or following appendicitis (K35.-)K35.-
- puerperal peritonitis (O85)O85
- retroperitoneal infections (K68.-)K68.-
K00-K95chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 10
K65.1code
Inclusion terms
- Abdominopelvic abscess
- Abscess (of) omentum
- Abscess (of) peritoneum
- Mesenteric abscess
- Retrocecal abscess
- Subdiaphragmatic abscess
- Subhepatic abscess
- Subphrenic abscess
Index entries leading here 3
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) L02.91
- abdomen, abdominal
- cavity K65.1
- abdominopelvic K65.1
- intra-abdominal K65.1
- intraperitoneal K65.1
- mesentery, mesenteric K65.1
- omentum K65.1
- peritoneum, peritoneal (perforated) (ruptured) K65.1
- pelvic
- male K65.1
- pelvic
- retrocecal K65.1
- subdiaphragmatic K65.1
- subhepatic K65.1
- subphrenic K65.1
- pelvis, pelvic
- male, peritoneal K65.1
- diaphragm, diaphragmatic K65.1
- epiploon, epiploic K65.1
- abdomen, abdominal
- Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) K65.9
- with or following
- abscess K65.1
- with or following
- Sepsis (generalized) (unspecified organism) A41.9
- intra-abdominal K65.1
Alongside this code 6 same parent — K65
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.