2026 ICD-10-CM Diagnosis Code M30.3Mucocutaneous lymph node syndrome [Kawasaki]

ICD-10-CM CodesM00–M99M30-M36M30

ICD-10-CM M30.3
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M30.3 is a billable ICD-10-CM diagnosis code for mucocutaneous lymph node syndrome [Kawasaki]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 545 through 547. Coders also document this condition as acute febrile mucocutaneous lymph node syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Systemic lupus erythematosus and connective tissue disorders and Vasculitis.

Code Identity

ICD-10-CM Code
M30.3
Billable Status
Yes — Valid for Submission
Code Describes
Mucocutaneous lymph node syndrome [Kawasaki]
Short Description
Mucocutaneous lymph node syndrome [Kawasaki]
Same as the full description in the CMS dataset.
Parent Code
Polyarteritis nodosa and related conditions

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM30-M36Systemic connective tissue disorders
CategoryM30Polyarteritis nodosa and related conditions
This CodeM30.3Mucocutaneous lymph node syndrome [Kawasaki]

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute febrile mucocutaneous lymph node syndrome
  • Aneurysm of coronary artery due to and following acute febrile mucocutaneous lymph node syndrome
  • Aneurysm of coronary vessels
  • Myocarditis due to Kawasaki disease
  • Primary systemic arteritis
  • Vasculitis of medium sized vessel

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.

    • Kawasaki's syndrome
    • Syndrome
      • mucocutaneous lymph node (acute febrile) (MCLS)

Clinical ClassificationClinical

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

CCSR MUS024
Systemic lupus erythematosus and connective tissue disorders
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR CIR037
Vasculitis
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Mucocutaneous Lymph Node Syndrome

    an acute, febrile, mucocutaneous condition accompanied by swelling of cervical lymph nodes in infants and young children. the principal symptoms are fever, congestion of the ocular conjunctivae, reddening of the lips and oral cavity, protuberance of tongue papillae, and edema or erythema of the extremities.

Patient EducationClinical

Kawasaki Disease

Kawasaki disease is a rare illness that usually affects small children. Other names for the disease are Kawasaki syndrome and mucocutaneous lymph node syndrome. It is a type of vasculitis, which is inflammation of the blood vessels. Kawasaki disease is serious, but most children can fully recover if they are treated right away.

The full article covers:

  • What is Kawasaki disease?
  • What causes Kawasaki disease?
  • Who is more likely to develop Kawasaki disease?
  • What are the symptoms of Kawasaki disease?
  • What other problems can Kawasaki disease cause?
  • How is Kawasaki disease diagnosed?
  • What are the treatments for Kawasaki disease?

Read the full article at MedlinePlus

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

Convert M30.3 to ICD-9-CMHistory

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

ICD-9-CM
446.1 Mucocutan lymph node syn
Exact Match The mapping is direct, with no qualifiers.

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 M30.3Overview

Is M30.3 (Polyarteritis nodosa and related conditions) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report mucocutaneous lymph node syndrome [Kawasaki] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M30.3 group to?

When mucocutaneous lymph node syndrome [Kawasaki] is the principal diagnosis on an inpatient stay, it groups to MS-DRG 545, 546, 547, with relative weights from 0.8362 to 2.4817 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M30.3?

Under the General Equivalence Mappings, mucocutaneous lymph node syndrome [Kawasaki] converts to ICD-9-CM 446.1 (mucocutan lymph node syn). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.