ICD-10 Code K66.8 – Other specified disorders of peritoneum (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K66.8 – Other specified disorders of peritoneum
What it is
K66.8 is used for a peritoneal disorder that is documented but does not fit a more specific ICD-10-CM code. It covers other named peritoneal conditions when the record supports the diagnosis.
Clinical signs
Clinical features vary; refer to documentation. Peritoneal disorders may present with abdominal pain, distention, tenderness, or imaging findings involving the peritoneum, but the exact pattern depends on the stated condition.
When to use this code
Use K66.8 when the provider identifies a specific peritoneal disorder and no more precise code exists in ICD-10-CM. It is appropriate when the chart clearly documents an “other specified” peritoneal condition. Check documentation if the note only describes nonspecific abdominal symptoms.
Do not use for
Do not use this code for generalized peritonitis, peritoneal abscess, or other separately coded peritoneal diseases. Also avoid it when the documentation supports a more specific diagnosis.
Coding tip
Match the exact provider wording and confirm that no specific peritoneal code applies before assigning K66.8.