ICD-10 Code for Serositis
The ICD-10-CM code for serositis is K65.8 — Other peritonitis. This is the code the Alphabetic Index gives for serositis with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
Billable
Which serositis code should you use?
The Alphabetic Index lists 2 codes under Serositis, multiple. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources