Dermatomyositis: Symptoms, Causes and Treatments

Dermatomyositis is a rare autoimmune condition that affects the skin and muscles, causing distinct rashes and muscle inflammation. Recognising the symptoms of dermatomyositis is essential for early diagnosis and effective treatment. This article will explore dermatomyositis’s key signs and symptoms, its causes, and available treatment options. Let’s begin by understanding what dermatomyositis is.

What is Dermatomyositis?

Dermatomyositis is a rare inflammatory disease belonging to a group of muscle disorders called inflammatory myopathy. It is characterised by its unique skin manifestations and muscle inflammation. This condition can affect people of any age, but it is most commonly diagnosed in adults between the ages of 50 and 70, with women being twice as likely to develop it as men. Now, let’s take a closer look at the specific symptoms of dermatomyositis.

What are the Symptoms of Dermatomyositis?

Dermatomyositis presents with a range of symptoms that primarily affect the skin and muscles:

• Skin rash: Red or purple, itchy, painful rashes on sun-exposed areas like eyelids (heliotrope) and knuckles (Gottron’s papules).
• Discolouration: Rash resembling a shawl or “v-neck” pattern.
• Muscle weakness: Affects hips, thighs, shoulders, and neck.
• Other changes: Scaling, redness, calcinosis, and red, swollen fingernails.
• Systemic symptoms: Fatigue, fever, weight loss, and difficulty swallowing or breathing.
• Complications: Organ inflammation, joint pain, and cancer risk.

What Causes Dermatomyositis?

The precise cause of dermatomyositis remains a mystery, but it is thought to result from a complex interplay between various factors.

• Genetics: HLA types like HLA-A68 and HLA-DQA1*0104 increase dermatomyositis risk.
• Autoimmunity: An autoimmune disorder causing inflammation in muscles and skin.
• Triggers: Viral infections (e.g., Coxsackie B, parvovirus), sun exposure, medications (e.g., statins), and smoking.
• Paraneoplastic syndromes: Linked to cancers, especially in the GI tract, lungs, breast, and lymphoid tissues, in adults over 40-50.

What are the Risk Factors of Dermatomyositis?

Several genetic, environmental, and demographic factors can increase an individual’s risk of developing dermatomyositis.

• Gender: More common in females.
• Genetics: Linked to HLA-A68, HLA-DRB10301, and HLA-DQA1*0104.
• Environmental exposure: Triggered by viral infections, sun exposure, and medications.
• Demographics: Higher prevalence in Southern Europe and urban areas due to UV-B light or genetics.
• Smoking and pollution: Linked to juvenile dermatomyositis.

What are the Complications of Dermatomyositis?

Dermatomyositis can lead to a range of severe complications affecting various bodily systems.

• Musculoskeletal: Difficulty swallowing, aspiration pneumonia, and breathing issues.
• Skin/Connective Tissue: Calcium deposits, atrophy, hyperpigmentation, and scarring.
• Cardiovascular/Pulmonary: Cardiomyopathy, arrhythmias, interstitial lung disease, and atherosclerosis.
• Gastrointestinal: Vasculitis, abdominal pain, constipation, and bleeding ulcers (common in children).

How is Dermatomyositis Diagnosed?

Diagnosing dermatomyositis involves a thorough evaluation of your symptoms and various diagnostic tests. Here’s what you can expect:

• Clinical Exam: The doctor assesses muscle weakness and skin changes like heliotrope rash and Gottron sign.
• Blood Tests: Checks for elevated muscle enzymes and myositis autoantibodies.
• EMG: Measures electrical activity, showing patterns in affected muscles.
• MRI: Detects muscle inflammation and aids biopsy guidance.
• Muscle Biopsy: Gold standard, reveals perifascicular atrophy and inflammation.

How is Dermatomyositis Treated?

Treatment for dermatomyositis aims to reduce inflammation, suppress the overactive immune system, and manage symptoms to improve your quality of life. Your doctor may recommend a combination of the following:

• Glucocorticoids: These medications are often used as the first-line treatment to reduce inflammation and swelling quickly. However, long-term use can have side effects, so your doctor will work to taper the dose over time.
• Immunosuppressive Medicines: These medicines may be combined with glucocorticoids to help control the immune system’s attack on your muscles.
• Intravenous Immunoglobulin (IVIG): This treatment involves receiving an infusion of healthy antibodies to help regulate the immune response.
• Monoclonal Antibodies: These medicines target specific immune cells and may be combined with other treatments for difficult-to-manage cases.
• Supportive Care: Physical therapy is crucial to help maintain and improve muscle strength. Surgical removal may be necessary if calcium deposits develop under the skin (calcinosis). Your doctor will also address any associated complications, such as difficulty swallowing or breathing.
• Juvenile Dermatomyositis: Treatment for children with dermatomyositis may include immunosuppressants and IVIG, with the approach tailored based on the severity and specific organ involvement.

How to Prevent Dermatomyositis?

While there are no surefire ways to prevent dermatomyositis, understanding and managing potential risk factors may be beneficial. Consider the following:

• Maintain a healthy lifestyle and avoid potential triggers, such as certain viral infections or specific medications, as genetic and environmental factors are suspected to play a role in the development of dermatomyositis.
• Protect your skin from sun exposure by using sunscreens and wearing protective clothing to help manage skin symptoms if they appear.
• Attend regular medical checkups to aid in the early detection and management of the condition.
• Be cautious about vaccinations, medications, and other medical procedures linked to dermatomyositis in some cases.

When to See a Doctor

Suppose you experience any characteristic symptoms of dermatomyositis, such as muscle weakness, particularly in the muscles closest to the trunk of the body, or a patchy, reddish rash on the skin. In that case, it is essential to consult a doctor immediately. Other signs that warrant medical attention include difficulty swallowing, rising from a chair, or combing your hair, as well as generalised fatigue and joint pain. Early diagnosis and treatment can significantly reduce the risk of severe complications and improve outcomes. Seeking timely medical advice is crucial for the effective management of dermatomyositis.

Conclusion

Dermatomyositis is a complex autoimmune disorder that requires prompt medical attention and comprehensive management. Individuals can better navigate their diagnosis and treatment plan by understanding its symptoms, potential causes, and available treatments. Although there is no cure, long-term management with medications, physical therapy, and lifestyle adjustments can help control symptoms and improve quality of life. Regular follow-up with healthcare providers is essential to monitor the condition and adjust treatments. With proper care and support, people with dermatomyositis can lead fulfilling lives despite the challenges posed by this condition.

Frequently Asked Questions (FAQs)

References

• https://www.ncbi.nlm.nih.gov/books/NBK558917/
• https://pmc.ncbi.nlm.nih.gov/articles/PMC10924937/
• https://www.jaad.org/article/S0190-9622(19)32308-4/abstract