ICD-10 · PDGM grouping
H70 Mastoiditis and related conditions
All 40 codes in the H70 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.
ICD-10-CM FY2027 · CMS grouper v07.2.26
Codes in family
40
Can lead a claim
30
Cannot lead a claim
10
What CMS assigns to H70
30 of the 40 codes group to MMTA - Other; 10 are assigned no clinical group. None of the 40 is assigned a comorbidity subgroup. 30 of the 40 can lead a claim.
Every code in H70
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 |
|---|---|---|---|---|
| H70.0 Acute mastoiditis | ||||
| H70.00 Acute mastoiditis without complications | ||||
| H70.001 | Acute mastoiditis without complications, right ear | Can lead a claim | A | None |
| H70.002 | Acute mastoiditis without complications, left ear | Can lead a claim | A | None |
| H70.003 | Acute mastoiditis without complications, bilateral | Can lead a claim | A | None |
| H70.009 | Acute mastoiditis without complications, unspecified ear | Cannot lead a claimUnspecified diagnosis code not acceptable as principal diagnosis since there is a more specific code available that would further accurately identify the condition | None | None |
| H70.01 Subperiosteal abscess of mastoid | ||||
| H70.011 | Subperiosteal abscess of mastoid, right ear | Can lead a claim | A | None |
| H70.012 | Subperiosteal abscess of mastoid, left ear | Can lead a claim | A | None |
| H70.013 | Subperiosteal abscess of mastoid, bilateral | Can lead a claim | A | None |
| H70.019 | Subperiosteal abscess of mastoid, unspecified ear | Cannot lead a claimUnspecified diagnosis code not acceptable as principal diagnosis since there is a more specific code available that would further accurately identify the condition | None | None |
| H70.09 Acute mastoiditis with other complications | ||||
| H70.091 | Acute mastoiditis with other complications, right ear | Can lead a claim | A | None |
| H70.092 | Acute mastoiditis with other complications, left ear | Can lead a claim | A | None |
| H70.093 | Acute mastoiditis with other complications, bilateral | Can lead a claim | A | None |
| H70.099 | Acute mastoiditis with other complications, unspecified ear | Cannot lead a claimUnspecified diagnosis code not acceptable as principal diagnosis since there is a more specific code available that would further accurately identify the condition | None | None |
| H70.1 Chronic mastoiditis | ||||
| H70.10 | Chronic mastoiditis, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.11 | Chronic mastoiditis, right ear | Can lead a claim | A | None |
| H70.12 | Chronic mastoiditis, left ear | Can lead a claim | A | None |
| H70.13 | Chronic mastoiditis, bilateral | Can lead a claim | A | None |
| H70.2 Petrositis | ||||
| H70.20 Unspecified petrositis | ||||
| H70.201 | Unspecified petrositis, right ear | Can lead a claim | A | None |
| H70.202 | Unspecified petrositis, left ear | Can lead a claim | A | None |
| H70.203 | Unspecified petrositis, bilateral | Can lead a claim | A | None |
| H70.209 | Unspecified petrositis, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.21 Acute petrositis | ||||
| H70.211 | Acute petrositis, right ear | Can lead a claim | A | None |
| H70.212 | Acute petrositis, left ear | Can lead a claim | A | None |
| H70.213 | Acute petrositis, bilateral | Can lead a claim | A | None |
| H70.219 | Acute petrositis, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.22 Chronic petrositis | ||||
| H70.221 | Chronic petrositis, right ear | Can lead a claim | A | None |
| H70.222 | Chronic petrositis, left ear | Can lead a claim | A | None |
| H70.223 | Chronic petrositis, bilateral | Can lead a claim | A | None |
| H70.229 | Chronic petrositis, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.8 Other mastoiditis and related conditions | ||||
| H70.81 Postauricular fistula | ||||
| H70.811 | Postauricular fistula, right ear | Can lead a claim | A | None |
| H70.812 | Postauricular fistula, left ear | Can lead a claim | A | None |
| H70.813 | Postauricular fistula, bilateral | Can lead a claim | A | None |
| H70.819 | Postauricular fistula, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.89 Other mastoiditis and related conditions | ||||
| H70.891 | Other mastoiditis and related conditions, right ear | Can lead a claim | A | None |
| H70.892 | Other mastoiditis and related conditions, left ear | Can lead a claim | A | None |
| H70.893 | Other mastoiditis and related conditions, bilateral | Can lead a claim | A | None |
| H70.899 | Other mastoiditis and related conditions, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.9 Unspecified mastoiditis | ||||
| H70.90 | Unspecified mastoiditis, unspecified ear | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| H70.91 | Unspecified mastoiditis, right ear | Can lead a claim | A | None |
| H70.92 | Unspecified mastoiditis, left ear | Can lead a claim | A | None |
| H70.93 | Unspecified mastoiditis, bilateral | Can lead a claim | A | 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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