Dermatomyositis

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Last reviewed: 5 Aug 2025

Last updated: 19 Mar 2024

Dermatomyositis (DM) is an idiopathic autoimmune inflammatory disorder characterized by a myopathy with a distinctive cutaneous eruption.

Skin lesions are frequently the initial presenting complaint, with muscle involvement developing later. Some patients have cutaneous involvement alone. Hallmark features include a heliotrope rash, Gottron papules, photosensitivity, and nail fold capillary dilatation.

May be associated with interstitial lung disease, cardiac involvement, esophageal involvement, dystrophic calcification, and underlying malignancy.

Initial treatment of muscle disease is with high-dose oral corticosteroids, followed by the addition of immunosuppressants or intravenous immunoglobulin in refractory cases.

Skin manifestations are treated with topical antipruritics and topical corticosteroids. Antimalarials and topical tacrolimus can be used in resistant disease.

Immunosuppressants and intravenous immunoglobulin are generally used for resistant and severe skin disease. Photoprotection is advised in all patients.

Definition

Dermatomyositis (DM) is an idiopathic autoimmune inflammatory myopathy characterized by distinctive skin manifestations. Diagnosis is based on the presence of a symmetric proximal myopathy, elevated muscle enzymes, myopathic changes on electromyography, a characteristic muscle biopsy, and a typical skin rash (e.g., periorbital dusky violaceous erythema, or macular violaceous erythema such as in V, shawl, and Gottron signs).[1] Some patients present with typical cutaneous manifestations but have delayed-onset, subclinical, or absent muscle disease.[2] DM occurs in both adult and juvenile forms and can overlap with other connective tissue disorders (systemic sclerosis, systemic lupus erythematosus, mixed connective tissue disease, and, less often, rheumatoid arthritis and Sjögren syndrome).[3] It may be associated with interstitial lung disease, cardiac involvement, esophageal involvement, dystrophic calcification, and underlying malignancy. Adult-onset DM is significantly associated with occult malignancy.[4]

History and exam

Key diagnostic factors

Gottron papules
heliotrope rash with or without periorbital edema
macular violaceous erythema
periungual erythema, nail-fold capillary dilation, cuticular overgrowth
"mechanic's" hands
proximal muscle weakness

Full details

Other diagnostic factors

photosensitivity
poikiloderma vasculare atrophicans
pruritus
fatigue and malaise
dyspnea
weight loss
fever
myalgia
arthralgia
dysphagia
palpitations and syncope
Raynaud phenomenon
cutaneous calcinosis
erythroderma
vesiculobullous lesions
leukocytoclastic vasculitis
cutaneous necrosis
nonscarring alopecia

Full details

Risk factors

genetic predisposition
bimodal age distribution: children and age >40 years
female sex
black race
ultraviolet radiation
infectious agents
drugs
immunization

Full details

Diagnostic tests

1st tests to order

serum creatine kinase (CK)
serum aldolase
muscle biopsy
electromyogram (EMG)
skin biopsy
antinuclear antibody (ANA)
myositis-specific antibodies (MSAs) and myositis-associated antibodies (MAAs)

Full details

Tests to consider

muscle MRI
ECG
echocardiography
cardiac troponin I
chest x-ray (CXR)
pulmonary function tests (PFTs)
high-resolution CT of chest
barium swallow or videofluoroscopic assessment of swallow

Full details

Treatment algorithm

ACUTE

severe disease or acute flares

ONGOING

combined muscle and skin disease

skin disease only

Contributors

Authors

Michael Edward Farrugia, MD, PgDip, MRCP (Derm)

Dermatology Specialty Trainee

Lauriston Building

NHS Lothian

Edinburgh

Disclosures

MEF has received funding from AbbVie to attend an international dermatology conference.

Meng May Chee, MBChB, MD, MRCP

Consultant Rheumatologist

Queen Elizabeth University Hospital

Glasgow

Disclosures

MMC accepted a sponsored invitation to attend the EULAR e-congress in June 2020.

Girish Gupta, FRCP

Consultant Dermatologist

Lauriston Building

Edinburgh

Disclosures

GG has received honoraria for membership of advisory boards from Almirall, Leo, Lilly, Mylan, and Novartis. GG has also received lecture fees from AbbVie, Almirall, Galderma, La Roche Posay, Leo, Mylan, and Novartis. GG declares that none of the payments are related to this topic or treatments discussed in this topic, and there are no contractual agreements to disseminate product information.

Acknowledgements

Dr Michael E. Farrugia, Dr Meng May Chee, and Dr Girish Gupta would like to gratefully acknowledge Dr Sarah A. Saunders, Dr Rajan Madhok, and Dr Nicola Alcorn, previous contributors to this topic.

Disclosures

SAS and NA declare that they have no competing interests. RM declared holding shares in GSK to the value less than £12,000.

Peer reviewers

Nizar Souayah, MD

Assistant Professor of Neurology

Director of EMG Laboratory & Peripheral Neuropathy Center

Department of Neurology & Neurosciences

New Jersey Medical School

Newark

Disclosures

NS declares that he has no competing interests.

Sami Khella, MD

Physician

Department of Neurology

Penn Presbyterian Medical Center

University of Pennsylvania Health System

Philadelphia

Disclosures

SK declares that he has no competing interests.

Yusuf Yazici, MD

Assistant Professor

Associate Director

Arthritis Program

Director

Behcet's Syndrome Center

Seligman Center for Advanced Therapeutics

New York University Hospital for Joint Diseases

New York

Disclosures

YY has served as a consultant for Bristol-Myers Squibb, Roche, Celgene, Centocor, and UCB, and has been a speaker for Pfizer and Bristol-Myers Squibb.

Peer reviewer acknowledgements

BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.

Disclosures

Peer reviewer affiliations and disclosures pertain to the time of the review.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Gerami P, Schope JM, McDonald L, et al. A systematic review of adult-onset clinically amyopathic dermatomyositis (dermatomyositis sine myositis): a missing link within the spectrum of idiopathic inflammatory myopathies. J Am Acad Dermatol. 2006 Apr;54(4):597-613. Abstract

Dalakas MC, Hohlfeld R. Polymyositis and dermatomyositis. Lancet. 2003 Sep 20;362(9388):971-82. Abstract

DeWane ME, Waldman R, Lu J. Dermatomyositis: clinical features and pathogenesis. J Am Acad Dermatol. 2020 Feb;82(2):267-81. Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

Differentials
- Subacute cutaneous lupus erythematosus (SCLE)
- Psoriasis
- Cutaneous T-cell lymphoma
More Differentials
Guidelines
- 2023 American College of Rheumatology (ACR) guideline for the screening and monitoring of interstitial lung disease in people with systemic autoimmune rheumatic disease
- 2023 American College of Rheumatology (ACR) guideline for the treatment of interstitial lung disease in people with systemic autoimmune rheumatic disease
More Guidelines
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Dermatomyositis

Summary

Definition

History and exam

Key diagnostic factors

Other diagnostic factors

Risk factors

Diagnostic tests

1st tests to order

Tests to consider

Treatment algorithm

severe disease or acute flares

combined muscle and skin disease

skin disease only

Contributors

Authors

Michael Edward Farrugia, MD, PgDip, MRCP (Derm)

Disclosures

Meng May Chee, MBChB, MD, MRCP

Disclosures

Girish Gupta, FRCP

Disclosures

Acknowledgements

Disclosures

Peer reviewers

Nizar Souayah, MD

Disclosures

Sami Khella, MD

Disclosures

Yusuf Yazici, MD

Disclosures

Peer reviewer acknowledgements

Disclosures

References

Key articles

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

Differentials

Guidelines

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

Log in to access all of BMJ Best Practice