All ICD10 Codes

A18.4

Billable
ChapterA00–B99
Ranksubcategory
Official Description

Tuberculosis of skin and subcutaneous tissue

Metadata & Insights
  • •2026 ICD-10-CM Edition - Effective October 1, 2025.
  • •Billable/specific code (valid for reimbursement).
  • •Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99).

Instructional Notes

Includes
  • Erythema induratum, tuberculous
  • Lupus exedens
  • Lupus vulgaris NOS
  • Lupus vulgaris of eyelid
  • Scrofuloderma
  • Tuberculosis of external ear
Excludes2(Not included here)
  • lupus erythematosus (L93.-)
  • systemic lupus erythematosus (M32.-)
General instructions are available for the parent sections:
View CH1 NotesView A15-A19 Notes

Clinical Hierarchy

CH1Certain infectious and parasitic diseases (A00-B99)
A15-A19Tuberculosis (A15-A19)
A18Tuberculosis of other organs
A18.4Tuberculosis of skin and subcutaneous tissue

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to A18.4:

blockA15-A19
Tuberculosis (A15-A19)
View context instructions
chapterCH1
Certain infectious and parasitic diseases (A00-B99)
View context instructions

Alphabetic Index Mentions

These are Diagnosis Index lookup paths that route to A18.4. Use them as entry terms for search, then confirm final coding instructions in the Tabular List and notes above.

25 raw paths
Acnitis (primary)1 unique routes
Direct index entry→A18.4
Bazin's disease (primary) (tuberculous)1 unique routes
Direct index entry→A18.4
Cellulitis (diffuse) (phlegmonous) (septic) (suppurative)1 unique routes
tuberculous (primary)→A18.4
Erythema, erythematous (infectional) (inflammation)3 unique routes
induratum (nontuberculous)
tuberculous→A18.4
nodosum
tuberculous→A18.4
tuberculous (primary)→A18.4
Gumma (syphilitic)2 unique routes
scrofulous (tuberculous)→A18.4
tuberculous→A18.4
Lichen1 unique routes
scrofulosus (primary) (tuberculous)→A18.4
Lichenoides tuberculosis (primary)1 unique routes
Direct index entry→A18.4
Lupus5 unique routes
exedens→A18.4
tuberculous→A18.4(2 variants)
eyelid→A18.4
vulgaris→A18.4(2 variants)
eyelid→A18.4
Paronychia1 unique routes
tuberculous (primary)→A18.4
Scrofulide (primary) (tuberculous)1 unique routes
Direct index entry→A18.4
Scrofuloderma, scrofulodermia (any site) (primary)1 unique routes
Direct index entry→A18.4
Scrofulosus lichen (primary) (tuberculous)1 unique routes
Direct index entry→A18.4
Tarsitis (eyelid)1 unique routes
tuberculous→A18.4
Tuberculid, tuberculide (indurating, subcutaneous) (lichenoid) (miliary) (papulonecrotic) (primary) (skin)1 unique routes
Direct index entry→A18.4
Tuberculosis, tubercular, tuberculous (calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)4 unique routes
abscess (respiratory)
skin (primary)→A18.4
cellulitis (primary)→A18.4
colliquativa (primary)→A18.4
cutis (colliquativa) (primary)→A18.4

MS-DRG Classification

2026 v43.1

This code is grouped within the following Diagnosis Related Group(s) for clinical reimbursement:

DRG 606
Minor Skin Disorders with MCC
DRG 607
Minor Skin Disorders without MCC
DRG 974
HIV with Major Related Condition with MCC
DRG 975
HIV with Major Related Condition with CC
DRG 976
HIV with Major Related Condition without CC/MCC

Cross Reference

Find Procedures (ICD-10-PCS)

Find surgical and procedural codes related to Tuberculosis of skin and subcutaneous tissue.

Search PCS Codes