amyopathic dermatomyositis

146 Newtown Road
Woolston
Southampton
SO19 9HR

Tel: 023 8044 9708
Fax: 023 8039 6402
Web: www.myositis.org.uk
Best time to telephone: Monday - Friday, 10am - 3pm

The Myositis Support Group is the only UK charity specific for the inflammatory myopathies; Dermatomyositis, Polymyositis, Inclusion Body Myositis and Juvenile Dermatomyositis.

The Aims of the Myositis Support Group are:

• To provide information to sufferers and their families
• To help give them a better understanding of their illness
• To relieve the isolation felt by an individual when a rare illness is diagnosed
• To guide sufferers in the right direction for treatment
• To raise awareness of the conditions
• To raise funds to promote and support research

The Myositis Support Group is able to offer:

• Free UK membership
• Newsletters
• Information Guides
• Annual meeting/conference
• Advice on specialist centres
• Interactive website - Discussion Forum and Email Contacts (Buddy Listing)
• Listening Ear Telephone Network - volunteers who offer support
• Active fundraising

Clinical Manifestations of Dermatomyositis

BACKGROUND: Dermatomyositis (DM) is a rare inflammatory musculocutaneous disease of presumed autoimmune origin. OBJECTIVE: The purpose of our study was to analyze the clinical manifestations of DM, METHODS: A retrospective study of 18 patients with DM is analyzed. RESULTS: 1. The range of age was from 3 to 72 years, and the most frequent age group was 46-60 (38.9%). Male to female ratio was 1:8. 2. Among the 18 patients, 61.1% was classified as DM, 38.9% as amyopathic dermatomyositis (ADM), 3. Skin rash was noted 100%, itching 72.2%, proximal muscle weakness 61.1%, myalgia 38.2%, arthralgia 22.2%, hair loss 22.2%, Raynaud's phenomenon 22.2%. Arnong the skin rash, Gottron's sign was most frequent (83.3%), followed by heliotrope rash (72.2%), Gottron's papule (66.6%). 4. Serum CPK level was elevated in 38.9%, LDH 88.9%, SGOT 44.4%, SGPT 33.3%, and ESR 61.1%. 5. DM patients were treated with prednisolone 400mg/kg/day and hydroxychloroquine 400mg/day (childhood 5mg/kg/day) for 4~8 weeks. Four patients who had severe skin manifestations and pruritus added methotrexate. Four ADM patients were treated with hydroxychloroquine 5mg/kg/day only. Two ADM patients were added prednisolone 1mg/kg/day for 6 weeks.


Affiliation:
Department of Dermatology, Seoul National University College of Medicine, Seoul, Korea. jhchung@snu.ac.kr

Muscle fiber atrophy: Perifascicular distribution

• Smallest (atrophic) muscle fibers are located near regions of "avascular" perimysium
  • Muscle fibers near perimysial vesels are larger.
• Atrophic muscle fibers near the "avascular" perimysium have abnormal internal architecture, but not necrotic.
• Abnormal internal architecture: See
  • H & E
  • Gomori trichrome
  • NADH
  • Mitochondria
•   Necrotic and regenerating fibers are more common in DM-like disorders in adults (IMPP).
• Nuclei in small muscle fibers are enlarged and commonly internal.

Inflammatory Myopathies

What is Dermatomyositis?

Dermatomyositis is one of a group of muscle diseases known as the inflammatory myopathies, which are characterized by chronic muscle inflammation accompanied by muscle weakness. Dermatomyositis’ cardinal symptom is a skin rash that precedes or accompanies progressive muscle weakness. The rash looks patchy, with bluish-purple or red discolorations, and characteristically develops on the eyelids and on muscles used to extend or straighten joints, including knuckles, elbows, heels, and toes. Red rashes may also occur on the face, neck, shoulders, upper chest, back, and other locations, and there may be swelling in the affected areas. The rash sometimes occurs without obvious muscle involvement. Adults with dermatomyositis may experience weight loss or a low-grade fever, have inflamed lungs, and be sensitive to light. Children and adults with dermatomyositis may develop calcium deposits, which appear as hard bumps under the skin or in the muscle (called calcinosis). Calcinosis most often occurs 1-3 years after the disease begins. These deposits are seen more often in children with dermatomyositis than in adults. In some cases of dermatomyositis, distal muscles (muscles located away from the trunk of the body, such as those in the forearms and around the ankles and wrists) may be affected as the disease progresses. Dermatomyositis may be associated with collagen-vascular or autoimmune diseases, such as lupus.

Is there any treatment?

There is no cure for dermatomyositis, but the symptoms can be treated. Options include medication, physical therapy, exercise, heat therapy (including microwave and ultrasound), orthotics and assistive devices, and rest. The standard treatment for dermatomyositis is a corticosteroid drug, given either in pill form or intravenously. Immunosuppressant drugs, such as azathioprine and methotrexate, may reduce inflammation in people who do not respond well to prednisone. Periodic treatment using intravenous immunoglobulin can also improve recovery. Other immunosuppressive agents used to treat the inflammation associated with dermatomyositis include cyclosporine A, cyclophosphamide, and tacrolimus. Physical therapy is usually recommended to prevent muscle atrophy and to regain muscle strength and range of motion. Many individuals with dermatomyositis may need a topical ointment, such as topical corticosteroids, for their skin disorder. They should wear a high-protection sunscreen and protective clothing. Surgery may be required to remove calcium deposits that cause nerve pain and recurrent infections.

What is the prognosis?

Most cases of dermatomyositis respond to therapy. The disease is usually more severe and resistant to therapy in individuals with cardiac or pulmonary problems.

What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research relating to dermatomyositis in laboratories at the NIH and support additional research through grants to major medical institutions across the country. Currently funded research is exploring patterns of gene expression among the inflammatory myopathies, the role of viral infection as a precursor to the disorders, and the safety and efficacy of various treatment regimens.

Dermatomyositis : Skin symptoms aid in diagnosis by about.com

Dermatomyositis is an inflammatory muscle disease (myopathy). It primarily affects the skin and muscles but may affect other organ systems of the body. Research suggests that it is an autoimmune disorder, in which the body attacks its own healthy cells.

Dermatomyositis may occur in people of any age. In adults the peak onset is at about 50 years of age. Known as juvenile dermatomyositis in children, the peak age of onset is 5-10 years old. It affects females twice as often as males, and occurs in people of all ethnic backgrounds.

Symptoms
Dermatomyositis produces symptoms in the skin and muscles such as:

·         A reddish-purple-to-dusky red rash in a symmetrical distribution around the eyes (heliotrope rash)

·         Dark red bumps (Gottron papules) or raised blotches (plaques) over the knuckles, finger or toe joints, elbows, ankles, or knees

·         In children, firm yellow or flesh-colored nodules (calcinosis) may appear over the same bony prominences

·         Some individuals also have a scaly scalp or diffuse hair loss

·         Muscle symptoms include fatigue or weakness when climbing stairs, rising from a sitting position, or lifting the arms.

Although less common, individuals with dermatomyositis may also have systemic symptoms such as arthritis, shortness of breath, or difficulty swallowing or speaking. Adults older than 60 years of age with dermatomyositis seem to have a higher risk of developing cancer.

Diagnosis
Individuals with dermatomyositis often have skin disease as their initial symptoms. The characteristic rash and papules, as well as calcinosis nodules in children, will suggest the diagnosis. Sometimes the skin lesions may be mistaken for those of lupus erythematosus, psoriasis, or lichen planus. Children with dermatomyositis may be hard to diagnose until the characteristic skin symptoms become apparent.

In addition to the skin symptoms, blood tests can be done to detect muscle enzymes and markers of inflammation. Some individuals with dermatomyositis have a positive antinuclear antibody (ANA) blood test. Magnetic resonance imaging (MRI), electromyography (EMG), and muscle biopsy can assess muscle disease and damage.

Treatment
Treatment for dermatomyositis focuses on controlling the muscle disease and skin symptoms. Generally a corticosteroid such as prednisone is administered to decrease muscle inflammation. If the steroid side effects become severe, immunosuppressant or cytotoxic medications, such as methotrexate (Rheumatrex) or azathioprine (Imuran), may be used. Methotrexate may also help reduce the skin symptoms. Individuals with dermatomyositis are photosensitive and should protect their skin from sun exposure.

If muscle weakness is present, physical and occupational therapy may help improve muscle function and prevent complications such as contractures. Some individuals may need treatment for systemic symptoms or complications.

Prognosis
Most individuals with dermatomyositis will require long-term treatment. Calcinosis may complicate the treatment of the disease in children and adolescents. Some individuals may develop cancer or organ failure, leading to a shortened life expectancy. However, many individuals respond well to treatment and have relief of some or all of their symptoms.