2026 ICD-10-CM Diagnosis Code K57.40Diverticulitis of both small and large intestine with perforation and abscess without bleeding
ICD-10-CM Codes›K00–K95›K55-K64›K57
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Chronic Condition
K57.40 is a billable ICD-10-CM diagnosis code for diverticulitis of both small and large intestine with perforation and abscess without bleeding. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 18 closely related codes. Coders also document this condition as abscess of intestine co-occurrent and due to diverticular disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Diverticulosis and diverticulitis, Gastrointestinal and biliary perforation, and Peritonitis and intra-abdominal abscess.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abscess of intestine co-occurrent and due to diverticular disease
- Complicated diverticular disease of large intestine
- Diverticular disease of small and large intestine
- Diverticulitis of small and large intestine with perforation
- Perforated diverticulum of intestine
- Perforated diverticulum of large intestine
- Perforated diverticulum of small intestine
- Perforation and abscess with diverticular disease of small and large intestine
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) L02.91
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Abscess
An abscess is a pocket of pus. You can get an abscess almost anywhere in your body. When an area of your body becomes infected, your body's immune system tries to fight the infection. White blood cells go to the infected area, collect within the damaged tissue, and cause inflammation. During this process, pus forms.
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Convert K57.40 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K57.40Overview
Is K57.40 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report diverticulitis of both small and large intestine with perforation and abscess without bleeding on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does K57.40 group to?
When diverticulitis of both small and large intestine with perforation and abscess without bleeding is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.
Is K57.40 a CC or MCC?
CMS lists K57.40 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 18 closely related codes in its exclusion list.
What is the ICD-9 equivalent of K57.40?
Under the General Equivalence Mappings, diverticulitis of both small and large intestine with perforation and abscess without bleeding converts to ICD-9-CM 562.11 (dvrtcli colon w/o hmrhg), 562.01 (dvrtcli sml int w/o hmrg), and 569.5 (intestinal abscess). The mapping is approximate, so confirm the match fits the documentation.
