L03.112 ICD-10-CM Code: Cellulitis of left axilla

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for L03.112 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 L03.112 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for L03.112

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

Before you code L03.112

1. 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).

   ReviewL03.111 · right

   Guide: Laterality coding →

Choose the right path

1. 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.

   ReviewL03.111 · right

Consider L03.112. 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).

Anatomical site

At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.

Laterality

Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).

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

• Excludes2 — not part of L03.112(27 notes)

  Coding workflow: The conditions named in this note are not included in L03.112. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareL03.01, L03.03, L03.314, K61, H60.1, H00.0

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

• Use Additional Code — after identifying L03.112(1 note)

  Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with L03.112 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

  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 L03.112 with…

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

The codes most likely to be picked instead of L03.112 — 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.

• L03.119— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Cellulitis of unspecified part of limb” takes L03.119; specificity in the record moves it back here.

  Full comparison: L03.112 vs L03.119 →

• L03.111— 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 L03.111.

  Full comparison: L03.112 vs L03.111 →

• L03.01— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of cellulitis of fingers adds L03.01; it is not part of this code and both may be reported when both are documented.

  Full comparison: L03.112 vs L03.01 →

• L03.03— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of cellulitis of toes adds L03.03; it is not part of this code and both may be reported when both are documented.

  Full comparison: L03.112 vs L03.03 →

• L03.314— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of groin adds L03.314; it is not part of this code and both may be reported when both are documented.

  Full comparison: L03.112 vs L03.314 →

• K61— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of cellulitis of anal and rectal region adds K61; it is not part of this code and both may be reported when both are documented.

  Full comparison: L03.112 vs K61 →

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. 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
2. 1 Use Additional Code instruction — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
3. 27 Excludes2 entries — 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

• CC as a secondary diagnosis (FY2026). 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 structured relationships — computed from published CMS and AHRQ datasets

Other codes that name L03.112 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 Excludes1 note: I89.1 — Lymphangitis (via L03.-).

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

Referenced by 4 Excludes2 notes: L89 — Pressure ulcer (via L03.-), L97 — Non-pressure chronic ulcer of lower limb, not elsewhere classified (via L03.-), L98.4 — Non-pressure chronic ulcer of skin, not elsewhere classified (via L03.-), L98.A — Non-pressure chronic ulcer of upper limb, not elsewhere classified (via L03.-).

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

Referenced by 1 Use Additional Code instruction: T65.84 — Toxic effect of xylazine (via L03.-).

These codes instruct coders to additionally report this code when it applies.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 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 55 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 7 MS-DRGs: DRG 573 (MDC 09), DRG 574 (MDC 09), DRG 575 (MDC 09), DRG 602 (MDC 09), DRG 603 (MDC 09), 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):SKN001 — Skin and subcutaneous tissue infections (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.

B78.1 — Cutaneous strongyloidiasis, E83.2 — Disorders of zinc metabolism, L02.411 — Cutaneous abscess of right axilla, L02.412 — Cutaneous abscess of left axilla, L02.413 — Cutaneous abscess of right upper limb, L02.414 — Cutaneous abscess of left upper limb, L02.811 — Cutaneous abscess of head [any part, except face], L02.818 — Cutaneous abscess of other sites, L02.91 — Cutaneous abscess, unspecified, L03.111 — Cellulitis of right axilla, L03.113 — Cellulitis of right upper limb, L03.114 — Cellulitis of left upper limb, L03.121 — Acute lymphangitis of right axilla, L03.122 — Acute lymphangitis of left axilla, L03.123 — Acute lymphangitis of right upper limb, L03.124 — Acute lymphangitis of left upper limb, L03.811 — Cellulitis of head [any part, except face], L03.818 — Cellulitis of other sites, L03.891 — Acute lymphangitis of head [any part, except face], L03.898 — Acute lymphangitis of other sites, +34 more

Same condition, opposite side

Same category and title, differing only in which side of the body is affected.

L03.111 — Cellulitis of right axillaCompare L03.112 vs L03.111 →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Skin and subcutaneous tissue infections).

L03.021 — Acute lymphangitis of right finger, L03.022 — Acute lymphangitis of left finger, L03.029 — Acute lymphangitis of unspecified finger, L03.031 — Cellulitis of right toe, L03.032 — Cellulitis of left toe, L03.039 — Cellulitis of unspecified toe, L03.041 — Acute lymphangitis of right toe, L03.042 — Acute lymphangitis of left toe, L03.049 — Acute lymphangitis of unspecified toe, L03.111 — Cellulitis of right axilla, L03.113 — Cellulitis of right upper limb, L03.114 — Cellulitis of left upper limb, L03.115 — Cellulitis of right lower limb, L03.116 — Cellulitis of left lower limb, L03.119 — Cellulitis of unspecified part of limb, L03.121 — Acute lymphangitis of right axilla, L03.122 — Acute lymphangitis of left axilla, L03.123 — Acute lymphangitis of right upper limb, L03.124 — Acute lymphangitis of left upper limb, L03.125 — Acute lymphangitis of right lower limb, +150 more

Same Index main term, other category

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

J38.3 — Other diseases of vocal cords (vocal cord), J38.7 — Other diseases of larynx (larynx), J39.1 — Other abscess of pharynx (pharynx), K11.3 — Abscess of salivary gland (submaxillary, gland), K12.2 — Cellulitis and abscess of mouth (mouth), K13.0 — Diseases of lips (lip), K61.0 — Anal abscess (anus), K61.1 — Rectal abscess (rectum), K65.0 — Generalized (acute) peritonitis (pelvis, pelvic, male), K68.9 — Other disorders of retroperitoneum (retroperitoneal), L98.3 — Eosinophilic cellulitis [Wells] (eosinophilic), N34.0 — Urethral abscess (periurethral), N48.22 — Cellulitis of corpus cavernosum and penis (penis), N49.0 — Inflammatory disorders of seminal vesicle (seminal vesicle), N49.2 — Inflammatory disorders of scrotum (scrotum), N49.8 — Inflammatory disorders of other specified male genital organs (genital organ NEC, male, specified NEC), N49.9 — Inflammatory disorder of unspecified male genital organ (genital organ NEC, male), N61.0 — Mastitis without abscess (nipple), N73.0 — Acute parametritis and pelvic cellulitis (periuterine, acute), N73.2 — Unspecified parametritis and pelvic cellulitis (periuterine), +13 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

HIV Screening Test

Contextual Map

Every relationship of L03.112 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 L03.112 with these 6 related codes in Claim Check

Hierarchy

• L00-L99 — Chapter 12: Diseases of the Skin and Subcutaneous Tissue (L00-L99) (L00-L99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L00-L08 — Infections of the skin and subcutaneous tissue[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• I89.1 — Lymphangitis[Excludes1](via L03.-): “acute lymphangitis (L03.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes2 notes

• L89 — Pressure ulcer[Excludes2](via L03.-): “skin infections (L00-L08)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• L97 — Non-pressure chronic ulcer of lower limb, not elsewhere classified[Excludes2](via L03.-): “skin infections (L00-L08)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• L98.4 — Non-pressure chronic ulcer of skin, not elsewhere classified[Excludes2](via L03.-): “skin infections (L00-L08)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• L98.A — Non-pressure chronic ulcer of upper limb, not elsewhere classified[Excludes2](via L03.-): “skin infections (L00-L08)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Use Additional Code instructions

• T65.84 — Toxic effect of xylazine[Use Additional Code](via L03.-): “cellulitis and acute lymphangitis (L03.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• SKN001 — Skin and subcutaneous tissue infections[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
• DRG 573 — SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITH MCC[MS-DRG]: “SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITH MCC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 574 — SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITH CC[MS-DRG]: “SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITH CC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 575 — SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITHOUT CC/MCC[MS-DRG]: “SKIN GRAFT FOR SKIN ULCER OR CELLULITIS WITHOUT CC/MCC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 602 — CELLULITIS WITH MCC[MS-DRG]: “CELLULITIS WITH MCC (MDC 09)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 603 — CELLULITIS WITHOUT MCC[MS-DRG]: “CELLULITIS WITHOUT MCC (MDC 09)”— 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 09 — Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast[MDC crossing]: “Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast — 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. 7,376 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)

• L03 — Cellulitis and acute lymphangitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.0 — Cellulitis and acute lymphangitis of finger and toe[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.01 — Cellulitis of finger[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.011 — Cellulitis of right finger[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.012 — Cellulitis of left finger[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.019 — Cellulitis of unspecified finger[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.02 — Acute lymphangitis of finger[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• L03.021 — Acute lymphangitis of right finger[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

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 L03.112 in its code family, with their registry titles.

• L03.042 — Acute lymphangitis of left toe
• L03.049 — Acute lymphangitis of unspecified toe
• L03.1 — Cellulitis and acute lymphangitis of other parts of limb
• L03.11 — Cellulitis of other parts of limb
• L03.111 — Cellulitis of right axilla
• L03.113 — Cellulitis of right upper limb
• L03.114 — Cellulitis of left upper limb
• L03.115 — Cellulitis of right lower limb
• L03.116 — Cellulitis of left lower limb
• L03.119 — Cellulitis of unspecified part of limb

View all codes in the L03 family