2026 ICD-10-CM Diagnosis Code M79.3Panniculitis, unspecified

ICD-10-CM Codes›M00–M99›M70-M79›M79

ICD-10-CM M79.3
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M79.3 is a billable ICD-10-CM diagnosis code for panniculitis, unspecified. 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified connective tissue disease.

Code Identity

ICD-10-CM Code
M79.3
Billable Status
Yes — Valid for Submission
Code Describes
Panniculitis, unspecified
Short Description
Panniculitis, unspecified
Same as the full description in the CMS dataset.
Parent Code
M79
Other and unspecified soft tissue disorders, not elsewhere classified

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM70-M79Other soft tissue disorders
CategoryM79Other and unspecified soft tissue disorders, not elsewhere classified
This CodeM79.3Panniculitis, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acquired partial lipodystrophy
  • Acute panniculitis
  • Calcific panniculitis
  • Cold panniculitis
  • Cytophagic histiocytic panniculitis
  • Drug-induced panniculitis
  • Eosinophilic panniculitis
  • Factitial panniculitis
  • Infantile onset panniculitis with uveitis and systemic granulomatosis
  • Infective panniculitis
  • Lipoatrophic panniculitis
  • Lipophagic panniculitis
  • Lobular panniculitis
  • Neonatal cold panniculitis
  • Neonatal disorder of subcutaneous fat
  • Nodular panniculitis
  • Nutritional steatitis
  • Panniculitis
  • Panniculitis caused by corticosteroid therapy
  • Panniculitis due to action of lipolytic enzymes
  • Panniculitis due to alpha-1 anti-trypsin deficiency
  • Panniculitis due to cholesterol emboli
  • Panniculitis due to crystal deposition
  • Panniculitis due to hyperuricemia
  • Panniculitis due to immunological disorder
  • Panniculitis due to physical factor
  • Panniculitis in newborn
  • Panniculitis induced localized lipodystrophy
  • Panniculitis secondary to histiocytic disorder
  • Panniculitis secondary to malignancy
  • Panniculitis secondary to pancreatic disease
  • Panniculitis with complement deficiency
  • Pressure panniculitis
  • Septal panniculitis
  • Subcutaneous calcification
  • Traumatic fat necrosis

Tabular List NotesGuidance

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

Type 1 Excludes

  • lupus panniculitis L93.2
  • neck and back panniculitis M54.0
  • relapsing Weber-Christian panniculitis M35.6

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.

    • Lipodermatosclerosis
    • Panniculitis(nodular) (nonsuppurative)

Clinical ClassificationClinical

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

CCSR MUS025
Other specified connective tissue disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Panniculitis

    general term for inflammation of adipose tissue, usually of the skin, characterized by reddened subcutaneous nodules.

  • Panniculitis, Lupus Erythematosus

    a type of lupus erythematosus characterized by deep dermal or subcutaneous nodules, most often on the head, face, or upper arms. it is generally chronic and occurs most often in women between the ages of 20 and 45.

  • Panniculitis, Nodular Nonsuppurative

    a form of panniculitis characterized by recurrent episodes of fever accompanied by the eruption of single or multiple erythematous subcutaneous nodules on the lower extremities. they normally resolve, but tend to leave depressions in the skin. the condition is most often seen in women, alone or in association with other disorders.

  • Panniculitis, Peritoneal

    inflammation of the underlying layer of adipose tissue (panniculus) of the peritoneum, usually of the mesentery or the omentum. there are several forms with various names and are usually characterized by infiltration of lymphocytes and neutrophils, fat necrosis, and fibrosis.

  • Autoinflammation, Panniculitis, and Dermatosis Syndrome|AIPDS|ORAS|Otulin-Related Autoinflammatory Syndrome|Otulipenia

    an autosomal recessive condition caused by mutation(s) in the otulin gene, encoding ubiquitin thioesterase otulin. it is characterized by neonatal onset of recurrent fever, erythematous rash with painful nodules, painful joints, and lipodystrophy.

  • Lupus Panniculitis|Lupus Profundus

    a condition primarily affecting the subcutaneous adipose tissues, showing firm nodules that often resolve with lipoatrophy. there can be overlying changes of discoid lupus erythematosus. a skin biopsy showing lobular panniculitis with typical changes of lupus is needed to rule out other causes of panniculitis, including subcutaneous panniculitis-like t-cell lymphoma.

  • Panniculitis

    inflammation of the subcutaneous adipose tissue.

  • Panniculitis Ossificans

    a condition characterized by subcutaneous fat necrosis with heterotopic calcification. it often occurs as a result of injury to the area.

  • Peritoneal Panniculitis

    a disorder characterized by chronic inflammation and fibrosis of the adipose tissues in the peritoneal cavity.

  • Recurrent Subcutaneous Panniculitis-Like T-Cell Lymphoma

    the reemergence of subcutaneous panniculitis-like t-cell lymphoma after a period of remission.

  • Refractory Subcutaneous Panniculitis-Like T-Cell Lymphoma

    subcutaneous panniculitis-like t-cell lymphoma that is resistant to treatment.

  • Subcutaneous Panniculitis-Like T-Cell Lymphoma|SPTCL|Subcutaneous Panniculitis-Like T-Cell Lymphoma (Alpha/Beta Type)|Subcutaneous Panniculitis-Like T-Cell Lymphoma, Alpha/Beta Type|Subcutaneous panniculitis-like T-cell lymphoma|Subcutaneous panniculitis-like T-cell lymphoma

    a cytotoxic primary cutaneous t-cell lymphoma. recent studies suggest there are at least two groups of subcutaneous panniculitis-like t-cell lymphomas, each with distinct histologic features, immunophenotypic profile, and prognosis. one group has an alpha/beta, cd8 positive phenotype, involves only subcutaneous tissues, and usually has an indolent clinical course. the second group has a gamma/delta phenotype, is cd8 negative, often co-expresses cd56, is not confined to the subcutaneous tissues, and usually has a poor prognosis. in the recent who-eortc classification, the term subcutaneous panniculitis-like t-cell lymphoma is reserved for cases with an alpha/beta, cd8 positive phenotype. cases with a gamma/delta phenotype are included in the group of cutaneous gamma/delta t-cell lymphomas.

  • Weber-Christian Disease|Relapsing panniculitis [Weber-Christian]

    evidence of weber-christian disease.

  • Acquired Partial Lipodystrophy

    partial lipodystrophy, the cause of which is not present at birth. examples include lipodystrophy associated with human immunodeficiency virus (hiv) therapy, and barraquer-simons syndrome, associated with c3 nephritic factor.

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

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

Convert M79.3 to ICD-9-CMHistory

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

ICD-9-CM
729.30 Panniculitis, unsp site
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 M79.3Overview

Is M79.3 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report panniculitis, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M79.3 group to?

When panniculitis, unspecified 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 M79.3?

Under the General Equivalence Mappings, panniculitis, unspecified converts to ICD-9-CM 729.30 (panniculitis, unsp site). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.