2026 ICD-10-CM Diagnosis Code M35.6Relapsing panniculitis [Weber-Christian]
ICD-10-CM Codes›M00–M99›M30-M36›M35
- Billable — Valid for Submission
- Chronic Condition
M35.6 is a billable ICD-10-CM diagnosis code for relapsing panniculitis [Weber-Christian]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. Coders also document this condition as nodular panniculitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Systemic lupus erythematosus and connective tissue disorders.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Nodular panniculitis
- Relapsing febrile nodular nonsuppurative panniculitis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Christian-Weber disease - M35.6
- Panniculitis (nodular) (nonsuppurative) - M79.3
- relapsing - M35.6
- Weber-Christian disease - M35.6
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Christian-Weber disease
- Panniculitis(nodular) (nonsuppurative)
- relapsing
- Weber-Christian disease
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Connective Tissue Disorders
Your connective tissue supports many different parts of your body, such as your skin, eyes, and heart. It is like a "cellular glue" that gives your body parts their shape and helps keep them strong. It also helps some of your tissues do their work. It is made of many kinds of proteins. Cartilage and fat are types of connective tissue.
Read the full article at MedlinePlus
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Convert M35.6 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M35.6Overview
Is M35.6 (Other systemic involvement of connective tissue) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report relapsing panniculitis [Weber-Christian] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does M35.6 group to?
When relapsing panniculitis [Weber-Christian] is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of M35.6?
Under the General Equivalence Mappings, relapsing panniculitis [Weber-Christian] converts to ICD-9-CM 729.30 (panniculitis, unsp site). 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.
