2026 ICD-10-CM Diagnosis Code A43Nocardiosis

ICD-10-CM Codes›A00–B99›A30-A49›A43

ICD-10-CM A43
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A43 is a non-billable ICD-10-CM category code for nocardiosis, so it cannot be submitted on claims. Use a more specific code from this category instead, such as A43.0, A43.1, A43.8, and A43.9.

Code Identity

ICD-10-CM Code
A43
Billable Status
No — Non-Billable Category
Code Describes
Nocardiosis
Chapter
A30-A49
Other bacterial diseases

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA30-A49Other bacterial diseases
CategoryA43Nocardiosis
This CodeA43Nocardiosis

Specific Coding for NocardiosisOverview

Non-specific codes like A43 require more characters. Use one of these billable codes instead:

  • Use A43.0 for Pulmonary nocardiosis

  • Use A43.1 for Cutaneous nocardiosis

  • Use A43.8 for Other forms of nocardiosis

  • Use A43.9 for Nocardiosis, unspecified

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

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 A43Overview

Is A43 (Nocardiosis) a billable code?

No. This is a category header that groups the codes for nocardiosis, and headers cannot be submitted on claims. Claims for nocardiosis need a more specific code from this category, such as A43.0, A43.1, and A43.8.