ICD-10 · PDGM grouping
Z51 Encounter for other aftercare and medical care
All 8 codes in the Z51 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
8
Can lead a claim
3
Cannot lead a claim
5
What CMS assigns to Z51
3 of the 8 codes group to Complex Nursing Interventions (2) and MMTA - Other (1); 5 are assigned no clinical group. None of the 8 is assigned a comorbidity subgroup. 3 of the 8 can lead a claim.
Every code in Z51
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 |
|---|---|---|---|---|
| Z51.0 | Encounter for antineoplastic radiation therapy | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Z51.1 Encounter for antineoplastic chemotherapy and immunotherapy | ||||
| Z51.11 | Encounter for antineoplastic chemotherapy | Can lead a claim | D | None |
| Z51.12 | Encounter for antineoplastic immunotherapy | Can lead a claim | D | None |
| Z51.5 | Encounter for palliative care | Can lead a claim | A | None |
| Z51.6 | Encounter for desensitization to allergens | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Z51.8 Encounter for other specified aftercare | ||||
| Z51.81 | Encounter for therapeutic drug level monitoring | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Z51.89 | Encounter for other specified aftercare | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Z51.A | Encounter for sepsis aftercare | 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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