ICD-10 · PDGM grouping
B33 Other viral diseases, not elsewhere classified
All 10 codes in the B33 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
10
Can lead a claim
10
Cannot lead a claim
0
What CMS assigns to B33
All 10 codes group to MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases. None of the 10 is assigned a comorbidity subgroup. Every code can lead a claim.
Every code in B33
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 |
|---|---|---|---|---|
| B33.0 | Epidemic myalgia | Can lead a claim | K | None |
| B33.1 | Ross River disease | Can lead a claim | K | None |
| B33.2 Viral carditis | ||||
| B33.20 | Viral carditis, unspecified | Can lead a claim | K | None |
| B33.21 | Viral endocarditis | Can lead a claim | K | None |
| B33.22 | Viral myocarditis | Can lead a claim | K | None |
| B33.23 | Viral pericarditis | Can lead a claim | K | None |
| B33.24 | Viral cardiomyopathy | Can lead a claim | K | None |
| B33.3 | Retrovirus infections, not elsewhere classified | Can lead a claim | K | None |
| B33.4 | Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS] | Can lead a claim | K | None |
| B33.8 | Other specified viral diseases | Can lead a claim | K | 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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