2026 ICD-10-CM Diagnosis Code R59Enlarged lymph nodes

ICD-10-CM Codes›R00–R99›R50-R69›R59

ICD-10-CM R59
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R59 is a non-billable ICD-10-CM category code for enlarged lymph nodes, so it cannot be submitted on claims. Use a more specific code from this category instead, such as R59.0, R59.1, and R59.9. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established.

Code Identity

ICD-10-CM Code
R59
Billable Status
No — Non-Billable Category
Code Describes
Enlarged lymph nodes
Chapter
R50-R69
General symptoms and signs

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR50-R69General symptoms and signs
CategoryR59Enlarged lymph nodes
This CodeR59Enlarged lymph nodes

Specific Coding for Enlarged lymph nodesOverview

Non-specific codes like R59 require more characters. Use one of these billable codes instead:

  • Use R59.0 for Localized enlarged lymph nodes

  • Use R59.1 for Generalized enlarged lymph nodes

  • Use R59.9 for Enlarged lymph nodes, unspecified

Tabular List NotesGuidance

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

Includes

  • swollen glands

Type 1 Excludes

  • lymphadenitis NOS I88.9
  • acute lymphadenitis L04
  • chronic lymphadenitis I88.1
  • mesenteric acute chronic lymphadenitis I88.0

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 R59Overview

Is R59 (Enlarged lymph nodes) a billable code?

No. This is a category header that groups the codes for enlarged lymph nodes, and headers cannot be submitted on claims. Claims for enlarged lymph nodes need a more specific code from this category, such as R59.0, R59.1, and R59.9.

Can R59 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the enlarged lymph nodes is established, that condition takes the principal position instead.