2026 ICD-10-CM Diagnosis Code A18.03Tuberculosis of other bones

ICD-10-CM Codes›A00–B99›A15-A19›A18

ICD-10-CM A18.03
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A18.03 is a billable ICD-10-CM diagnosis code for tuberculosis of other bones. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 539 through 541, 974 through 976. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Infective arthritis and Tuberculosis.

Code Identity

ICD-10-CM Code
A18.03
Billable Status
Yes — Valid for Submission
Code Describes
Tuberculosis of other bones
Short Description
Tuberculosis of other bones
Same as the full description in the CMS dataset.
Parent Code
A18.0
Tuberculosis of bones and joints

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA15-A19Tuberculosis
CategoryA18Tuberculosis of other organs
This CodeA18.03Tuberculosis of other bones

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bacterial osteomyelitis
  • Infection of bone of pelvis and femur
  • Infection of humerus
  • Osteitis of shoulder region
  • Tuberculosis of bone
  • Tuberculosis of bone of lower leg
  • Tuberculosis of bone of upper limb
  • Tuberculosis of bones and/or joints
  • Tuberculosis of bones of lower extremity
  • Tuberculosis of bones of shoulder region
  • Tuberculosis of limb bones
  • Tuberculosis of mastoid process
  • Tuberculosis of multiple limb bones
  • Tuberculosis of pelvis and femur
  • Tuberculosis of the bones of multiple sites
  • Tuberculosis of the bones of the ankle and/or foot
  • Tuberculosis of the bones of the hand
  • Tuberculosis of the forearm bone
  • Tuberculosis of the upper arm bone
  • Tuberculous dactylitis
  • Tuberculous osteomyelitis
  • Tuberculous osteonecrosis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Tuberculous mastoiditis
  • Tuberculous osteomyelitis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Caries
      • bone NEC
    • Caries
      • limb NEC (tuberculous)
    • Caries
      • mastoid process (chronic)
        • tuberculous
    • Caries
      • nose (tuberculous)
    • Caries
      • orbit (tuberculous)
    • Caries
      • tuberculous
    • Dactylitis
      • tuberculous
    • Mastoiditis(coalescent) (hemorrhagic) (suppurative)
      • in (due to)
        • tuberculosis
    • Mastoiditis(coalescent) (hemorrhagic) (suppurative)
      • tuberculous
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • abscess (respiratory)
        • bone
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • abscess (respiratory)
        • bone
          • specified site NEC
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • bone
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • bone
        • limb NEC
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • dactylitis
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • ear (inner) (middle)
        • bone
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • finger
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • hand
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • iliac spine (superior)
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • jaw
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • mastoiditis
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • pelvis (bony)
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • shoulder (joint)
        • blade
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • sinus (any nasal)
        • bone
    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • skeletal NEC

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MUS001
Infective arthritis
Default principal diagnosis: inpatient No · outpatient No
CCSR INF001
Tuberculosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Bone Infections

Like other parts of the body, bones can get infected. The infections are usually bacterial, but can also be fungal. They may spread to the bone from nearby skin or muscles, or from another part of the body through the bloodstream.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert A18.03 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
015.60 TB of mastoid-unspec
Approximate The match is approximate rather than exact.
ICD-9-CM
015.70 TB of bone NEC-unspec
Approximate The match is approximate rather than exact.
ICD-9-CM
015.70 TB of bone NEC-unspec
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
730.88 Bone infect NEC-oth site
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A18.03Overview

Is A18.03 (Tuberculosis of bones and joints) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report tuberculosis of other bones on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does A18.03 group to?

When tuberculosis of other bones is the principal diagnosis on an inpatient stay, it groups to MS-DRG 539, 540, 541, 974, 975, 976, with relative weights from 0.7715 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of A18.03?

Under the General Equivalence Mappings, tuberculosis of other bones converts to ICD-9-CM 015.60 (TB of mastoid-unspec), 015.70 (TB of bone NEC-unspec), and 015.70 (TB of bone NEC-unspec). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.