Dermatomyositis Symptoms: A Complete Guide

Dermatomyositis Symptoms: Muscle Weakness & Skin Rash Explained

Dermatomyositis is an autoimmune disease that causes muscle inflammation. Dermatomyositis symptoms can occur in children (aged between 5 and 15 years) and adults (aged between 40 and 60 years). According to statistics, it is a rare condition, affecting only 1 in 1 million people annually. Furthermore, the mortality rate of dermatomyositis is approximately 10%.

Dermatomyositis is a type of inflammatory myopathy that causes both rashes and muscle weakness. It occurs when the immune system mistakenly attacks healthy tissues in the body.

This form of myopathy can become severe and impact a patient’s ability to swallow and breathe properly. It tends to progress rapidly and requires immediate intervention from a healthcare professional.

If you are wondering about the symptoms of dermatomyositis, its causes, diagnosis, and treatment, this article provides comprehensive insights.

What are the Types of Dermatomyositis?

Dermatomyositis can be classified into six types. They are discussed below:

1. Classic Dermatomyositis (CDM): Involves cutaneous manifestations or skin rashes along with muscle weakness.
2. Amyopathic Dermatomyositis (ADM): Similar to CDM, it involves skin rashes but lacks muscle involvement for at least six months after diagnosis.
3. Hypomyopathic Dermatomyositis (HDM): Does not cause noticeable muscle weakness. However, laboratory findings may show abnormal muscle enzymes and features of myopathy.
4. Clinically Amyopathic Dermatomyositis (CADM): In this type, patients experience skin disease without clinical muscle involvement but may have subclinical muscle inflammation.
5. Juvenile Dermatomyositis (JDM): A subset seen in children, juvenile dermatomyositis symptoms include muscle tenderness, swelling, and characteristic skin rashes.
6. Dermatomyositis Sine Dermatitis (DMSD): In this variant, patients present with muscle inflammation but without any visible skin rashes.
    

What are dermatomyositis symptoms?

The most common dermatomyositis symptoms are skin rashes and muscle weakness, which may appear simultaneously or several months apart.

Patients with muscle involvement may experience:

• Difficulty rising from a chair or couch
• Trouble sitting upright
• Challenges standing up after lying down
• Problems climbing stairs
   

The characteristic skin rashes typically appear on the:

• Chest and front of the shoulders
• Eyelids and surrounding areas
• Scalp
• The neck and back of the shoulders
   

Additionally, patients may notice skin discolouration, small bumps (Gottron's papules) on the elbows, knees, and hands, joint pain, "mechanic's hands” (cracked, rough skin), and calcium deposits under the skin.

What are the Causes of Dermatomyositis?

Medical researchers are constantly working to find the reasons why an individual gets affected with dermatomyositis. Some of the known or suspected factors include:

1. Genetic Factors: Human leukocyte antigens (HLA genes) are essential for maintaining immune function. When altered by infections or environmental influences, these genes may increase susceptibility to dermatomyositis.
2. Issues with Autoimmunity: In dermatomyositis, the immune system attacks healthy skin and muscle tissues, leading to inflammation and damage.
3. Environmental Factors: Exposure to ultraviolet radiation and environmental pollutants has been associated with the onset of dermatomyositis.
4. Viral Infections: Certain viruses, such as parvovirus B19, Epstein-Barr virus, hepatitis viruses, influenza, and polyomavirus, are known to trigger symptoms in genetically predisposed individuals.

What are the diagnosis methods of dermatomyositis?

Heliotrope rashes and Gottron’s papules are key diagnostic features. Based on clinical symptoms, healthcare providers may recommend blood tests and biopsies.

Some of the common diagnostic methods include:

The following ways are used to diagnose dermatomyositis:

1. Blood tests: Like Creatine Phosphokinase (CPK) to check if a specific muscle enzyme has increased and autoantibody tests to check if the patient’s immune system is reacting to something harmful.
2. Biopsies: Skin biopsies and muscle biopsies to check if there is any inflammation and tissue damage.
3. Electromyography (EMG): This test helps to evaluate muscle strength and the possibility of skin changes by measuring the electrical activity of muscles.
4. Imaging tests: MRI is useful for detecting muscle inflammation. X-rays are not typically used to diagnose dermatomyositis.
    

How are dermatomyositis symptoms treated?

Since dermatomyositis may have genetic components, a complete cure is not always possible. However, with proper treatment, long-term management of dermatomyositis symptoms is achievable.

The following are effective ways to treat dermatomyositis:

• Corticosteroids: These are typically the first line of treatment. They help reduce inflammation and suppress immune system activity.
• Intravenous Immunoglobulin (IVIg): Used for patients who do not respond to corticosteroids. This therapy involves infusing immunoglobulins from donated blood to modulate the immune response.
• Immunosuppressants: Often used alongside corticosteroids to control severe inflammation or reduce the need for high steroid doses.
• Joint Protection: While joint protection may aid mobility, contractures are more common in other rheumatic diseases.
• Stress Management: Relaxation techniques such as deep breathing, yoga, and meditation can help improve overall well-being and reduce disease flare-ups.
• Therapies: Physical and speech therapy are often recommended, especially for patients with weakened throat muscles or reduced mobility.
   

Moreover, doctors recommend physical therapy and speech therapy for patients with weakened muscles in the throat or other parts of the body.

How to Manage Symptoms of Dermatomyositis?

Managing dermatomyositis symptoms involves a consistent treatment plan and lifestyle modifications, such as:

• Follow prescribed therapies diligently, whether physical, speech, or occupational.
• Avoid excessive sun exposure and use broad-spectrum sunscreen with at least SPF 50 to reduce flare-ups.
• Complete your full course of medication as prescribed.
• Attend regular follow-ups with healthcare providers to monitor progression or improvement.
   

What are the complications of dermatomyositis?

In addition to muscle weakness and skin issues, dermatomyositis may lead to other complications, including:

• Interstitial lung disease: Can cause coughing and breathing difficulties
• Cardiac issues: Arrhythmias or heart inflammation in some cases
• Swallowing difficulties: Leading to aspiration or malnutrition
• Associated cancers: Especially ovarian, lung, breast, and colon cancers in adults
   

Early detection and monitoring of these complications are essential for improving long-term outcomes.

Is it Possible to Have a Normal Life With Dermatomyositis?

Although dermatomyositis is chronic and may bring occasional complications, individuals can lead relatively normal lives with proper treatment and regular medical supervision. Monitoring symptoms, recognising flare-ups early, and adhering to therapies are key to maintaining quality of life.

Doctors often recommend a balanced, nutritious diet and a physically active lifestyle to support overall health and minimise disease impact.

How is dermatomyositis different from lupus?

Although dermatomyositis and lupus are both autoimmune diseases with overlapping symptoms like fatigue, rashes, and joint pain, they have key differences. Dermatomyositis often causes muscle weakness and characteristic skin rashes, such as Gottron’s papules.

Furthermore, cutaneous involvement in dermatomyositis often leads to macular erythema and skin ulceration. It is also associated with interstitial lung disease and respiratory muscle weakness, which are less common in lupus.

Lupus, on the other hand, typically presents with a butterfly-shaped rash across the cheeks and nose and can involve multiple organs, including the kidneys and heart. Skin ulcers are more severe and frequent in dermatomyositis, helping differentiate it from lupus clinically.

Final Words

Dermatomyositis symptoms can greatly affect daily life, often causing muscle weakness and mobility challenges. Recovery, especially through physical therapy, may take years. The condition is also linked to increased risks of cancers such as ovarian, lung, breast, and colon. Early diagnosis is essential for effective management.

With timely medical care, appropriate treatment, and healthy lifestyle choices, many people with dermatomyositis can maintain a good quality of life and reduce the severity and progression of symptoms.