H70.819 ICD-10-CM Code: Postauricular fistula, unspecified ear
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Coding at a Glance
- Tabular directives
- 2 Excludes1
Inpatient Payment Groups (MS-DRG)
Potential MS-DRG participation — not a DRG assignment.
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.
- MS-DRG 154 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH MCC (MDC 03)
- MS-DRG 155 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH CC (MDC 03)
- MS-DRG 156 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITHOUT CC/MCC (MDC 03)
- MS-DRG 791 — PREMATURITY WITH MAJOR PROBLEMS (MDC 15)
- MS-DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for H70.819 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on H70.819 itself; “inherited from” names the category or block whose note applies here.
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- preauricular sinus and cyst (Q18.1) Compare H70.819 vs Q18.1 →
- sinus, fistula, and cyst of branchial cleft (Q18.0) Compare H70.819 vs Q18.0 →
Source: inherited from H70.8
Coder workflow for H70.819
MedCoder structured workflow — derived from this code’s own official record
Before you code H70.819
- Unspecified does not mean incorrect. When the record gives no greater specificity, H70.819 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).
ReviewH70.811, H70.812, H70.813
See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →
- Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: unspecified). The unspecified-side code applies only when the record states no side. Laterality is assigned from the documented side; where a bilateral code exists and both sides are documented, it is used instead of two unilateral codes (Guidelines I.B.13).
ReviewH70.811 · right, H70.812 · left
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with H70.819. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Does the record document the detail a more specific sibling code needs?
Yes → Review the specific siblings in this subcategory.
No → Continue — H70.819 is appropriate when the documentation goes no further. - Does the documentation support a condition named in H70.819’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue. - Is the side documented?
Yes → Select the code for the documented side (or the bilateral code when both sides are documented and one exists).
No → Use the unspecified-side code only when the record states no side; a query is the alternative.ReviewH70.811 · right, H70.812 · left
Consider H70.819. Then confirm the code is valid for the date of service in the Verify section.
Documentation check
- The provider’s diagnostic statement
- Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
- Laterality
- Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).
- Any detail beyond this code’s title
- What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.
Official instructions as workflow
Excludes1 — check before selecting H70.819(2 notes)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with H70.819: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
See the official tabular notes · Guidelines I.A.12.a
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.
Coding question: Is a more specific sibling code supportable?
Path: Review the specific siblings in this subcategory and what each requires the record to state.
Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).
Documentation: Both the condition H70.819 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
Documentation: The record documents the condition on one side only.
Coding question: Which code in this family applies?
Path: Select the sibling code for the documented side.
Reason: Laterality is assigned from the documented side; the unspecified-side code is for records that state no side (Guidelines I.B.13).
ReviewH70.811 · right, H70.812 · left
Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Official Coding Guidelines
No excerpt in the ICD-10-CM Official Guidelines names this code specifically. Its chapter carries only this chapter-wide note:
Chapter 8: Diseases of the Ear and Mastoid Process (H60-H95)
Reserved for future guideline expansion
Verify Before Coding
- No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
MedCoder structured relationships — computed from published CMS and AHRQ datasets
Other codes that name H70.819 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.
Referenced by 1 Excludes2 note: H74 — Other disorders of middle ear mastoid (via H70.-).
These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.
MS-DRG Grouper Relationships (FY2026)
Potential MS-DRG participation — not a DRG assignment.
FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.
Named in the grouper logic of 5 MS-DRGs: DRG 154 (MDC 03), DRG 155 (MDC 03), DRG 156 (MDC 03), DRG 791 (MDC 15), DRG 793 (MDC 15).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Clinical classification (AHRQ CCSR):EAR002 — Diseases of middle ear and mastoid (except otitis media) (default).
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Related Codes
Same condition, opposite side
Same category and title, differing only in which side of the body is affected.
H70.811 — Postauricular fistula, right ear (right)Compare H70.819 vs H70.811 →, H70.812 — Postauricular fistula, left ear (left)Compare H70.819 vs H70.812 →
Same clinical category (CCSR)
AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Diseases of middle ear and mastoid (except otitis media)).
H70.212 — Acute petrositis, left ear, H70.213 — Acute petrositis, bilateral, H70.219 — Acute petrositis, unspecified ear, H70.221 — Chronic petrositis, right ear, H70.222 — Chronic petrositis, left ear, H70.223 — Chronic petrositis, bilateral, H70.229 — Chronic petrositis, unspecified ear, H70.811 — Postauricular fistula, right ear, H70.812 — Postauricular fistula, left ear, H70.813 — Postauricular fistula, bilateral, H70.891 — Other mastoiditis and related conditions, right ear, H70.892 — Other mastoiditis and related conditions, left ear, H70.893 — Other mastoiditis and related conditions, bilateral, H70.899 — Other mastoiditis and related conditions, unspecified ear, H70.90 — Unspecified mastoiditis, unspecified ear, H70.91 — Unspecified mastoiditis, right ear, H70.92 — Unspecified mastoiditis, left ear, H70.93 — Unspecified mastoiditis, bilateral, H71.00 — Cholesteatoma of attic, unspecified ear, H71.01 — Cholesteatoma of attic, right ear, +204 more
Same Index main term, other category
The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Fistula”; these codes share that main term but sit in a different category of the Tabular List.
A18.13 — Tuberculosis of other urinary organs (urethra, tuberculous), A18.15 — Tuberculosis of other male genital organs (scrotum, tuberculous), A18.18 — Tuberculosis of other female genital organs (rectovaginal, tuberculous), A18.32 — Tuberculous enteritis (in ano, tuberculous), D73.89 — Other diseases of spleen (splenocolic), E07.89 — Other specified disorders of thyroid (thyroid), G93.89 — Other specified disorders of brain (brain), G96.08 — Other cranial cerebrospinal fluid leak (cerebrospinal), H01.8 — Other specified inflammations of eyelid (eyelid), H04.61 — Lacrimal fistula (lacrimal), I25.41 — Coronary artery aneurysm (arteriovenous, coronary), I28.0 — Arteriovenous fistula of pulmonary vessels (arteriovenous, pulmonary), I31.8 — Other specified diseases of pericardium (pleuropericardial), I60.8 — Other nontraumatic subarachnoid hemorrhage (arteriovenous, brain, ruptured), I61.5 — Nontraumatic intracerebral hemorrhage, intraventricular (arteriovenous, brain, ruptured, intraventricular), I61.8 — Other nontraumatic intracerebral hemorrhage (arteriovenous, brain, ruptured, intracerebral), I67.1 — Cerebral aneurysm, nonruptured (brain, arteriovenous), I77.0 — Arteriovenous fistula, acquired (arteriovenous), I77.2 — Rupture of artery (artery), I89.8 — Other specified noninfective disorders of lymphatic vessels and lymph nodes (lymphatic), +114 more
Contextual Map
Every relationship of H70.819 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Run H70.819 with this related code in Claim Check
Hierarchy
- H60-H95 — Chapter 8: Diseases of the Ear and Mastoid Process (H60-H95) (H60-H95)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H65-H75 — Diseases of middle ear and mastoid[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Referenced by Excludes2 notes
- H74 — Other disorders of middle ear mastoid[Excludes2](via H70.-): “mastoiditis (H70.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Clinical classification (CCSR)
- EAR002 — Diseases of middle ear and mastoid (except otitis media)[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
MS-DRG Grouper
- DRG 154 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH MCC[MS-DRG]: “OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH MCC (MDC 03)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 155 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH CC[MS-DRG]: “OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITH CC (MDC 03)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 156 — OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITHOUT CC/MCC[MS-DRG]: “OTHER EAR, NOSE, MOUTH AND THROAT DIAGNOSES WITHOUT CC/MCC (MDC 03)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 791 — PREMATURITY WITH MAJOR PROBLEMS[MS-DRG]: “PREMATURITY WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS[MS-DRG]: “FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
MDC crossing
- MDC 03 — Diseases and Disorders of the Ear, Nose, Mouth and Throat[MDC crossing]: “Diseases and Disorders of the Ear, Nose, Mouth and Throat — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 5,147 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026
- MDC 15 — Newborns and Other Neonates with Conditions Originating in Perinatal Period[MDC crossing]: “Newborns and Other Neonates with Conditions Originating in Perinatal Period — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”— CMS MS-DRG Definitions Manual · FY2026
Nearest codes (40)
- H70 — Mastoiditis and related conditions[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.091 — Acute mastoiditis with other complications, right ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.092 — Acute mastoiditis with other complications, left ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.093 — Acute mastoiditis with other complications, bilateral[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.099 — Acute mastoiditis with other complications, unspecified ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.1 — Chronic mastoiditis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.10 — Chronic mastoiditis, unspecified ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- H70.11 — Chronic mastoiditis, right ear[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 32 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Coding guidelines Official source data
- ICD-10-CM Official Guidelines for Coding and Reporting (FY2026), quoted by section Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Inpatient payment groups Official source data
- CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "H70.819 — Postauricular fistula, unspecified ear." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/h70.819-postauricular-fistula-unspecified-ear
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionPostauricular fistula, unspecified ear
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to H70.819 in its code family, with their registry titles.
- H70.8 — Other mastoiditis and related conditions
- H70.81 — Postauricular fistula
- H70.811 — Postauricular fistula, right ear
- H70.812 — Postauricular fistula, left ear
- H70.813 — Postauricular fistula, bilateral
- H70.89 — Other mastoiditis and related conditions
- H70.891 — Other mastoiditis and related conditions, right ear
- H70.892 — Other mastoiditis and related conditions, left ear
- H70.893 — Other mastoiditis and related conditions, bilateral
- H70.899 — Other mastoiditis and related conditions, unspecified ear