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Q85.89 ICD-10-CM Code: Other phakomatoses, not elsewhere classified

Compare with another codeCheck this code on a claim

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
2 inclusion terms · 3 Excludes1
Risk adjustment
CMS-HCC V28: 1 category · CMS-HCC V22 category 12 · RxHCC V08 category 22

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Excludes1Never report with this code
  • Meckel-Gruber syndrome (Q61.9)
  • ataxia telangiectasia Louis-Bar
  • familial dysautonomia Riley-Day
IncludesWhat this code covers
  • Peutz-Jeghers syndrome
  • Sturge-Weber(-Dimitri) syndrome

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

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 v44, Appendix B.

  • MS-DRG 826 — MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASMS WITH MAJOR O.R. PROCEDURES WITH MCC (MDC 17)
  • MS-DRG 827 — MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASMS WITH MAJOR O.R. PROCEDURES WITH CC (MDC 17)
  • MS-DRG 828 — MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASMS WITH MAJOR O.R. PROCEDURES WITHOUT CC/MCC (MDC 17)
  • MS-DRG 829 — MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASMS WITH OTHER PROCEDURES WITH CC/MCC (MDC 17)
  • MS-DRG 830 — MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASMS WITH OTHER PROCEDURES WITHOUT CC/MCC (MDC 17)
  • MS-DRG 843 — OTHER MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASTIC DIAGNOSES WITH MCC (MDC 17)
  • MS-DRG 844 — OTHER MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASTIC DIAGNOSES WITH CC (MDC 17)
  • MS-DRG 845 — OTHER MYELOPROLIFERATIVE DISORDERS OR POORLY DIFFERENTIATED NEOPLASTIC DIAGNOSES WITHOUT CC/MCC (MDC 17)

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.

Risk Adjustment (CMS-HCC)

Payment categories this diagnosis maps to under CMS-HCC V28, payment year 2026.

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors

Other models: CMS-HCC V22 HCC 12 · RxHCC V08 HCC 22

Risk scores depend on the enrollee's full accepted diagnosis set and segment; a category mapping alone does not determine payment.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for Q85.89 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on Q85.89 itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Peutz-Jeghers syndrome
  • Sturge-Weber(-Dimitri) syndrome

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).

Coder workflow for Q85.89

MedCoder structured workflow — derived from this code’s own official record

Before you code Q85.89

  1. “Other” (NEC) means the condition is specified in the record but no dedicated code captures it. Confirm the documented form is not one a sibling code names before settling on Q85.89; if the record states no specifics at all, the unspecified sibling applies instead. “Other” codes are for documented conditions the classification gives no specific code; “unspecified” codes are for records lacking the detail (Guidelines I.A.9.a, I.A.9.b).

    ReviewQ85.81, Q85.83

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with Q85.89. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in Q85.89’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.

    ReviewQ61.9

Consider Q85.89. 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).
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 Q85.89(3 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with Q85.89: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareQ61.9

    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: Both the condition Q85.89 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).

ReviewQ61.9

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.

Don’t confuse Q85.89 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of Q85.89 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • Q61.9— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of Meckel-Gruber syndrome moves the case to Q61.9; the two are not reported together unless documented as unrelated.

    Full comparison: Q85.89 vs Q61.9 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Other phakomatoses, not elsewhere classified is a billable ICD-10-CM diagnosis code (Q85.89).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

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-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name Q85.89 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 2 Excludes1 notes across 2 chapters: L81 — Other disorders of pigmentation, Q82 — Other congenital malformations of skin.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 6 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 8 MS-DRGs: DRG 826 (MDC 17), DRG 827 (MDC 17), DRG 828 (MDC 17), DRG 829 (MDC 17), DRG 830 (MDC 17), DRG 843 (MDC 17), DRG 844 (MDC 17), DRG 845 (MDC 17).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):MAL010 — Other specified and unspecified congenital anomalies (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 clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

Q85.81 — PTEN hamartoma tumor syndrome, Q85.82 — Other Cowden syndrome, Q85.83 — Von Hippel-Lindau syndrome, Q85.9 — Phakomatosis, unspecified, Q89.9 — Congenital malformation, unspecified

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Prostate, Breast, and Other Cancers and Tumors) for risk-adjusted payment.

D43.8 — Neoplasm of uncertain behavior of other specified parts of central nervous system, D43.9 — Neoplasm of uncertain behavior of central nervous system, unspecified, D44.3 — Neoplasm of uncertain behavior of pituitary gland, D44.4 — Neoplasm of uncertain behavior of craniopharyngeal duct, D44.5 — Neoplasm of uncertain behavior of pineal gland, D44.6 — Neoplasm of uncertain behavior of carotid body, D44.7 — Neoplasm of uncertain behavior of aortic body and other paraganglia, D45 — Polycythemia vera, D47.3 — Essential (hemorrhagic) thrombocythemia, D49.6 — Neoplasm of unspecified behavior of brain, Q85.00 — Neurofibromatosis, unspecified, Q85.01 — Neurofibromatosis, type 1, Q85.02 — Neurofibromatosis, type 2, Q85.03 — Schwannomatosis, Q85.09 — Other neurofibromatosis, Q85.1 — Tuberous sclerosis, Q85.81 — PTEN hamartoma tumor syndrome, Q85.82 — Other Cowden syndrome, Q85.83 — Von Hippel-Lindau syndrome, Q85.9 — Phakomatosis, unspecified, +213 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Cancer Metastatic to Lung, Liver, Brain, and Other Organs; Acute Myeloid Leukemia Except Promyelocytic, Cancer Metastatic to Bone, Other and Unspecified Metastatic Cancer; Acute Leukemia Except Myeloid, Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers, Lung and Other Severe Cancers, Lymphoma and Other Cancers, Bladder, Colorectal, and Other Cancers

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Other specified and unspecified congenital anomalies).

Q84.4 — Congenital leukonychia, Q84.5 — Enlarged and hypertrophic nails, Q84.6 — Other congenital malformations of nails, Q84.8 — Other specified congenital malformations of integument, Q84.9 — Congenital malformation of integument, unspecified, Q85.1 — Tuberous sclerosis, Q85.8 — Other phakomatoses, not elsewhere classified, Q85.81 — PTEN hamartoma tumor syndrome, Q85.82 — Other Cowden syndrome, Q85.83 — Von Hippel-Lindau syndrome, Q85.9 — Phakomatosis, unspecified, Q86.0 — Fetal alcohol syndrome (dysmorphic), Q86.1 — Fetal hydantoin syndrome, Q86.2 — Dysmorphism due to warfarin, Q86.8 — Other congenital malformation syndromes due to known exogenous causes, Q87.0 — Congenital malformation syndromes predominantly affecting facial appearance, Q87.1 — Congenital malformation syndromes predominantly associated with short stature, Q87.11 — Prader-Willi syndrome, Q87.19 — Other congenital malformation syndromes predominantly associated with short stature, Q87.2 — Congenital malformation syndromes predominantly involving limbs, +59 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Angiomatosis”; these codes share that main term but sit in a different category of the Tabular List.

A79.89 — Other specified rickettsioses (bacillary), I78.0 — Hereditary hemorrhagic telangiectasia (hereditary familial), K76.4 — Peliosis hepatis (liver), Q82.8 — Other specified congenital malformations of skin

Contextual Map

Every relationship of Q85.89 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 Q85.89 with these 2 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Clinical classification (CCSR)

Risk adjustment (CMS-HCC)

  • HCC 23 — Prostate, Breast, and Other Cancers and Tumors [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

MDC crossing

  • MDC 17 — Myeloproliferative Diseases and Disorders, Poorly Differentiated Neoplasms[MDC crossing]: “Myeloproliferative Diseases and Disorders, Poorly Differentiated Neoplasms — 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. 4,735 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries

  • Angiomatosis, encephalotrigeminal[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Dimitri-Sturge-Weber disease[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Kraft-Weber-Dimitri disease[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Peutz-Jeghers disease or syndrome[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Phakomatosis, specified NEC[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Sturgedisease or syndrome (-Weber) (-Dimitri) (-Kalischer)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Syndrome, Peutz-Jeghers[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Syndrome, Sturge-Weber (-Dimitri)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Nearest codes (13)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Indexed Clinical Terms (8)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

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 FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 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 — v44 Release, file and checksum · Publisher’s page
Risk adjustment Official source data
2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release 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-derived 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 editorial 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.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 20, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

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. "Q85.89 — Other phakomatoses, not elsewhere classified." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/q85.89-other-phakomatoses-not-elsewhere-classified

Change history

  • FY2023 — October 1, 2022
    Added to the code set
    Other phakomatoses, not elsewhere classified
    FY2023 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to Q85.89 in its code family, with their registry titles.

View all codes in the Q85 family