2026 ICD-10-CM Diagnosis Code M33.09Juvenile dermatomyositis with other organ involvement

ICD-10-CM Codes›M00–M99›M30-M36›M33

ICD-10-CM M33.09
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M33.09 is a billable ICD-10-CM diagnosis code for juvenile dermatomyositis with other organ involvement. 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 cutaneous vasculitis due to childhood type dermatomyositis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Systemic lupus erythematosus and connective tissue disorders.

Code Identity

ICD-10-CM Code
M33.09
Billable Status
Yes — Valid for Submission
Code Describes
Juvenile dermatomyositis with other organ involvement
Short Description
Juvenile dermatomyositis with other organ involvement
Same as the full description in the CMS dataset.
Parent Code
M33.0
Juvenile dermatomyositis

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM30-M36Systemic connective tissue disorders
CategoryM33Dermatopolymyositis
This CodeM33.09Juvenile dermatomyositis with other organ involvement

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cutaneous vasculitis due to childhood type dermatomyositis
  • Myocarditis due to childhood type dermatomyositis
  • Necrotizing cutaneous vasculitis
  • Necrotizing cutaneous vasculitis due to childhood type dermatomyositis

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.

    • Dermatomyositis(acute) (chronic)
      • juvenile
        • with
          • specified organ involvement NEC
    • Dermatopolymyositis
      • juvenile
        • with
          • specified organ involvement NEC

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

Patient EducationClinical

Myositis

Myositis means inflammation of the muscles that you use to move your body. An injury, infection, or autoimmune disease can cause it. Two specific kinds are polymyositis and dermatomyositis. Polymyositis causes muscle weakness, usually in the muscles closest to the trunk of your body.

Read the full article at MedlinePlus

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

Convert M33.09 to ICD-9-CMHistory

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

ICD-9-CM
710.3 Dermatomyositis
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 M33.09Overview

Is M33.09 (Juvenile dermatomyositis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report juvenile dermatomyositis with other organ involvement on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M33.09 group to?

When juvenile dermatomyositis with other organ involvement 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 M33.09?

Under the General Equivalence Mappings, juvenile dermatomyositis with other organ involvement converts to ICD-9-CM 710.3 (dermatomyositis). The mapping is approximate, so confirm the match fits the documentation.

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.