2026 ICD-10-CM Diagnosis Code A17.9Tuberculosis of nervous system, unspecified

ICD-10-CM Codes›A00–B99›A15-A19›A17

ICD-10-CM A17.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A17.9 is a billable ICD-10-CM diagnosis code for tuberculosis of nervous system, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 867 through 869, 974 through 976. Coders also document this condition as tuberculosis of central nervous system. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (neither hereditary nor degenerative) and Tuberculosis.

Code Identity

ICD-10-CM Code
A17.9
Billable Status
Yes — Valid for Submission
Code Describes
Tuberculosis of nervous system, unspecified
Short Description
Tuberculosis of nervous system, unspecified
Same as the full description in the CMS dataset.
Parent Code
A17
Tuberculosis of nervous system

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA15-A19Tuberculosis
CategoryA17Tuberculosis of nervous system
This CodeA17.9Tuberculosis of nervous system, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Tuberculosis of central nervous system

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.

    • Tuberculosis, tubercular, tuberculous(calcification) (calcified) (caseous) (chromogenic acid-fast bacilli) (degeneration) (fibrocaseous) (fistula) (interstitial) (isolated circumscribed lesions) (necrosis) (parenchymatous) (ulcerative)
      • nervous system

Clinical ClassificationClinical

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

CCSR NVS020
Other nervous system disorders (neither hereditary nor degenerative)
Default principal diagnosis: inpatient No · outpatient No
CCSR INF001
Tuberculosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Tuberculosis

Tuberculosis (TB) is a bacterial disease that usually attacks the lungs. But it can also attack other parts of the body, including the kidneys, spine, and brain.

The full article covers:

  • What is tuberculosis (TB)?
  • What causes tuberculosis (TB)?
  • Who is more likely to get infected with tuberculosis (TB) germs?
  • Who is more likely to develop TB disease?
  • What are the symptoms of tuberculosis (TB)?
  • How is tuberculosis (TB) diagnosed?
  • What is the treatment for tuberculosis (TB)?

Read the full article at MedlinePlus

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

Convert A17.9 to ICD-9-CMHistory

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

ICD-9-CM
017.90 TB of organ NEC-unspec
Approximate The match is approximate rather than exact.

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 A17.9Overview

Is A17.9 (Tuberculosis of nervous system) a billable code?

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

What MS-DRG does A17.9 group to?

When tuberculosis of nervous system, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, 974, 975, 976, with relative weights from 0.7297 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of A17.9?

Under the General Equivalence Mappings, tuberculosis of nervous system, unspecified converts to ICD-9-CM 017.90 (TB of organ 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.