M1A.2721 ICD-10-CM Code: Drug-induced chronic gout, left ankle and foot, with tophus (tophi)

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for M1A.2721 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 M1A.2721 itself; “inherited from” names the category or block whose note applies here.

7th Character Guide

"The appropriate 7th character is to be added to each code from category M1A"

• 0 — without tophus (tophi)
• 1 — with tophus (tophi) (this page’s code)

Variant codes in this family

M1A.2720, M1A.2721

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for M1A.2721

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

Before you code M1A.2721

1. A 7th character is required in this family. Confirm the documentation supports the character assigned — its meaning in this family is defined in the official instruction. This page’s code carries “1”. The official 7th-character definitions for this family are quoted in the guide.

   See the 7th Character Guide

2. Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: left). 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).

   ReviewM1A.2711 · right, M1A.2791 · unspecified

   Guide: Laterality coding →

3. M1A.2721’s title joins a condition with an associated condition or complication. Confirm each component is documented. Where the classification presumes the link through the “with” convention, only a provider statement that the conditions are unrelated defeats it. A combination code is assigned only when it fully identifies the documented conditions; a required second code for the stage, type or manifestation is still reported when the notes ask for it (Guidelines I.B.9, I.A.15).

   Guide: Combination codes →

4. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with M1A.2721. 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 M1A.2721’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.

   ReviewM10

2. 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.

   ReviewM1A.2711 · right, M1A.2791 · unspecified

3. Does the documentation support one of this family’s 7th-character values?
   Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
   No → The code is invalid without its 7th character — query for the missing element.

Consider M1A.2721. Then work the Use Additional Code note, and 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).

7th-character basis

The documented element this family’s 7th character records (see the official definitions in the 7th Character Guide).

Acuity

Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).

The associated condition or complication

Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).

The conditions the Use Additional Code note names

Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.

Official instructions as workflow

• Excludes1 — check before selecting M1A.2721(1 note)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with M1A.2721: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareM10

  See the official tabular notes · Guidelines I.A.12.a

• Excludes2 — not part of M1A.2721(1 note)

  Coding workflow: The conditions named in this note are not included in M1A.2721. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareM10

  See the official tabular notes · Guidelines I.A.12.b

• Use Additional Code — after identifying M1A.2721(8 notes)

  Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with M1A.2721 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

  ReviewG99.0, N22, I43, H61.1, H62.8, H22

  See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

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 M1A.2721 with…

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

The codes most likely to be picked instead of M1A.2721 — 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.

• M10— 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 gout NOS moves the case to M10; the two are not reported together unless documented as unrelated.

  Full comparison: M1A.2721 vs M10 →

• M1A.2711— Laterality relationship (Review)

  Same condition; these differ only in which side is documented.

  The same condition on the other side; the documented side decides, and a bilateral code, where one exists, replaces the pair when both sides are documented.

  What moves you there: A documented right side moves the case to M1A.2711.

  Full comparison: M1A.2721 vs M1A.2711 →

• M1A.2791— Laterality relationship (Review)

  Same condition; these differ only in which side is documented.

  The same condition on the other side; the documented side decides, and a bilateral code, where one exists, replaces the pair when both sides are documented.

  What moves you there: A record that states no side takes M1A.2791; a documented side moves it back to a sided code.

  Full comparison: M1A.2721 vs M1A.2791 →

• M1A.2720— Encounter relationship (Review)

  Same underlying diagnosis, different encounter phase.

  The same diagnosis at a different phase of care; one encounter takes one 7th character.

  What moves you there: Documentation of a without tophus (tophi) moves the case to M1A.2720.

  Full comparison: M1A.2721 vs M1A.2720 →

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.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

1. A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
2. Laterality is coded in this family. Confirm the documented side matches the code — the opposite-side siblings are in the relationships section. See the opposite-side sibling codes
3. 8 Use Additional Code instructions — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
4. 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
5. 1 Excludes2 entry — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

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 M1A.2721 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: E72 — Other disorders of amino-acid metabolism (via M1A.-), E79 — Disorders of purine and pyrimidine metabolism (via M1A.-).

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

Referenced by 2 Excludes2 notes across 2 chapters: H61.1 — Noninfective disorders of pinna (via M1A.-), M10 — Gout (via M1A.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 5 Code First instructions across 4 chapters: G99.0 — Autonomic neuropathy in diseases classified elsewhere (via M1A.-), H22 — Disorders of iris and ciliary body in diseases classified elsewhere (via M1A.-), H62.8 — Other disorders of external ear in diseases classified elsewhere (via M1A.-), N08 — Glomerular disorders in diseases classified elsewhere (via M1A.-), N22 — Calculus of urinary tract in diseases classified elsewhere (via M1A.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

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 2 MS-DRGs: DRG 553 (MDC 08), DRG 554 (MDC 08).

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

Clinical classification (AHRQ CCSR):INJ030 — Drug induced or toxic related condition (default); MUS033 — Gout.

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.

M1A.2711 — Drug-induced chronic gout, right ankle and foot, with tophus (tophi) (right)Compare M1A.2721 vs M1A.2711 →, M1A.2791 — Drug-induced chronic gout, unspecified ankle and foot, with tophus (tophi) (unspecified)Compare M1A.2721 vs M1A.2791 →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Drug induced or toxic related condition, Gout).

M1A.2591 — Drug-induced chronic gout, unspecified hip, with tophus (tophi), M1A.2610 — Drug-induced chronic gout, right knee, without tophus (tophi), M1A.2611 — Drug-induced chronic gout, right knee, with tophus (tophi), M1A.2620 — Drug-induced chronic gout, left knee, without tophus (tophi), M1A.2621 — Drug-induced chronic gout, left knee, with tophus (tophi), M1A.2690 — Drug-induced chronic gout, unspecified knee, without tophus (tophi), M1A.2691 — Drug-induced chronic gout, unspecified knee, with tophus (tophi), M1A.2710 — Drug-induced chronic gout, right ankle and foot, without tophus (tophi), M1A.2711 — Drug-induced chronic gout, right ankle and foot, with tophus (tophi), M1A.2720 — Drug-induced chronic gout, left ankle and foot, without tophus (tophi), M1A.2790 — Drug-induced chronic gout, unspecified ankle and foot, without tophus (tophi), M1A.2791 — Drug-induced chronic gout, unspecified ankle and foot, with tophus (tophi), M1A.28X0 — Drug-induced chronic gout, vertebrae, without tophus (tophi), M1A.28X1 — Drug-induced chronic gout, vertebrae, with tophus (tophi), M1A.29X0 — Drug-induced chronic gout, multiple sites, without tophus (tophi), M1A.29X1 — Drug-induced chronic gout, multiple sites, with tophus (tophi), M32.0 — Drug-induced systemic lupus erythematosus, M34.2 — Systemic sclerosis induced by drug and chemical, M83.5 — Other drug-induced osteomalacia in adults, M87.10 — Osteonecrosis due to drugs, unspecified bone, +518 more

Same Index main term, other category

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

A52.77 — Syphilis of bone and joint

Contextual Map

Every relationship of M1A.2721 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 M1A.2721 with these 9 related codes in Claim Check

Hierarchy

• M00-M99 — Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) (M00-M99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• E72 — Other disorders of amino-acid metabolism[Excludes1](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• E79 — Disorders of purine and pyrimidine metabolism[Excludes1](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes2 notes

• H61.1 — Noninfective disorders of pinna[Excludes2](via M1A.-): “gouty tophi of ear (M1A.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• M10 — Gout[Excludes2](via M1A.-): “chronic gout (M1A.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code First instructions

• G99.0 — Autonomic neuropathy in diseases classified elsewhere[Code First](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• H22 — Disorders of iris and ciliary body in diseases classified elsewhere[Code First](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• H62.8 — Other disorders of external ear in diseases classified elsewhere[Code First](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• N08 — Glomerular disorders in diseases classified elsewhere[Code First](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• N22 — Calculus of urinary tract in diseases classified elsewhere[Code First](via M1A.-): “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• INJ030 — Drug induced or toxic related condition[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
• MUS033 — Gout[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• DRG 553 — BONE DISEASES AND ARTHROPATHIES WITH MCC[MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITH MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 554 — BONE DISEASES AND ARTHROPATHIES WITHOUT MCC[MS-DRG]: “BONE DISEASES AND ARTHROPATHIES WITHOUT MCC (MDC 08)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue[MDC crossing]: “Diseases and Disorders of the Musculoskeletal System and Connective Tissue — 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. 18,508 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Nearest codes (40)

• M1A — Chronic gout[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.2521 — Drug-induced chronic gout, left hip, with tophus (tophi)[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.259 — Drug-induced chronic gout, unspecified hip[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.2590 — Drug-induced chronic gout, unspecified hip, without tophus (tophi)[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.2591 — Drug-induced chronic gout, unspecified hip, with tophus (tophi)[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.26 — Drug-induced chronic gout, knee[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.261 — Drug-induced chronic gout, right knee[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• M1A.2610 — Drug-induced chronic gout, right knee, without tophus (tophi)[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

Common coding questions

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

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

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M1A.2721 in its code family, with their registry titles.

• M1A.271 — Drug-induced chronic gout, right ankle and foot
• M1A.2710 — Drug-induced chronic gout, right ankle and foot, without tophus (tophi)
• M1A.2711 — Drug-induced chronic gout, right ankle and foot, with tophus (tophi)
• M1A.272 — Drug-induced chronic gout, left ankle and foot
• M1A.2720 — Drug-induced chronic gout, left ankle and foot, without tophus (tophi)
• M1A.279 — Drug-induced chronic gout, unspecified ankle and foot
• M1A.2790 — Drug-induced chronic gout, unspecified ankle and foot, without tophus (tophi)
• M1A.2791 — Drug-induced chronic gout, unspecified ankle and foot, with tophus (tophi)
• M1A.28 — Drug-induced chronic gout, vertebrae
• M1A.28X0 — Drug-induced chronic gout, vertebrae, without tophus (tophi)

View all codes in the M1A family