ICD-10 · PDGM grouping
K66 Other disorders of peritoneum
All 4 codes in the K66 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
4
Can lead a claim
3
Cannot lead a claim
1
What CMS assigns to K66
3 of the 4 codes group to MMTA - Gastrointestinal tract and Genitourinary system; 1 is assigned no clinical group. None of the 4 is assigned a comorbidity subgroup. 3 of the 4 can lead a claim.
Every code in K66
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| K66.0 | Peritoneal adhesions (postprocedural) (postinfection) | Can lead a claim | J | None |
| K66.1 | Hemoperitoneum | Can lead a claim | J | None |
| K66.8 | Other specified disorders of peritoneum | Can lead a claim | J | None |
| K66.9 | Disorder of peritoneum, unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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