ICD-10 Code K26.1 – Acute duodenal ulcer with perforation (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K26.1 – Acute duodenal ulcer with perforation
What it is
K26.1 identifies an acute duodenal ulcer that has broken through the wall of the duodenum, creating a perforation. This is a serious complication and requires prompt clinical attention.
Clinical signs
Typical findings include sudden severe abdominal pain, signs of peritonitis, and possible abdominal rigidity. Clinical features vary; refer to documentation.
When to use this code
Use K26.1 when the provider documents an acute duodenal ulcer with perforation, whether confirmed by imaging, surgery, or operative note. Code it when perforation is clearly stated as part of the ulcer diagnosis. If the record only says duodenal ulcer without perforation, do not assign this code.
Do not use for
Do not use K26.1 for chronic duodenal ulcer without acute perforation or for gastric ulcer perforation. Check documentation if the site, acuity, or perforation status is unclear.
Coding tip
Look for explicit wording such as “perforated duodenal ulcer” before assigning K26.1.