A18.4 Tuberculosis of skin and subcutaneous tissue
The ICD-10-CM code for Tuberculosis of skin and subcutaneous tissue is A18.4 (FY2026). It is a billable, claim-ready diagnosis code.
Classification
- Section
- A15-A19: Tuberculosis (A15-A19)
- Category A18
- 38 codes (32 billable)
- FY2026 Status
- Stable since FY2024
Also Known As
ICD-10-CM Alphabetic Index entries that lead to A18.4:
- Scrofulosus lichen (primary) (tuberculous)
- Bazin's disease (primary) (tuberculous)
- Acnitis (primary)
- Scrofuloderma, scrofulodermia (any site) (primary)
- Tuberculid, tuberculide (indurating, subcutaneous) (lichenoid) (miliary) (papulonecrotic) (primary) (skin)
- Lichenoides tuberculosis (primary)
- Scrofulide (primary) (tuberculous)
- Cellulitis (diffuse) (phlegmonous) (septic) (suppurative) › tuberculous (primary)
Inclusion Terms
- Erythema induratum, tuberculous
- Lupus exedens
- Lupus vulgaris NOS
- Lupus vulgaris of eyelid
- Scrofuloderma
- Tuberculosis of external ear
U.S. Hospital Utilization
- An estimated 90 U.S. inpatient stays in 2023 included A18.4 among the documented diagnoses.
Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.
Official Coding Guidelines
HIV Infections (TOC entry)a. Human Immunodeficiency Virus (HIV) Infections .............................................................. 19
Infectious agents causing diseases in other chapters (TOC)b. Infectious agents as the cause of diseases classified to other chapters ................................. 22
Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026