Dermatomyositis
Related Terms
Adult dermatomyositis, amyopathic dermatomyositis (ADM), childhood dermatomyositis, dermatomyositis sine myositis, idiopathic inflammatory myopathy (IIM), juvenile dermatomyositis, polymyositis.
Background
Dermatomyositis, an inflammatory disease marked by muscle weakness and skin rash, was first described in 1975. It is characterized by progressive proximal symmetrical weakness (progressive weakening of muscles on both sides of the body), above-normal muscle enzyme levels, an abnormal electromyography reading (a measure of nerve impulses in the muscles), an abnormal muscle biopsy (a test in which muscle tissue is examined), and skin disease.
There are three different subcategories of this disease: childhood dermatomyositis, adult dermatomyositis, and dermatomyositis sine myositis (in which a person experiences skin symptoms but not the muscle symptoms).
The causes of dermatomyositis are unknown, but it may result from a problem with the immune system or from a viral infection. There have been case reports linking the disease to drugs such as statins, penicillamine, quinidine, and phenylbutazone.
It is estimated that there are 9.63 cases of dermatomyositis per million people. The disease may present at any age, but onset peaks in childhood and in late adulthood. Dermatomyositis is half as common in men as women. It may cause severe disability or death due to muscle weakness or involvement of vital organs such as the heart.
The National Institute of Neurological Disorders and Stroke (NINDS), along with the National Institute of Health (NIH), is funding research into gene expression patterns in the disease, the role of viral infection, and the safety of various treatments, including those currently in practice.
Signs and symptoms
Common symptoms include difficulty swallowing, muscle weakness, stiffness or soreness, purple-red skin rash (especially on the upper eyelids), shortness of breath, fever, muscle pain or tenderness, calcium deposits under the skin, gastrointestinal (GI) ulcers and infections, and interstitial lung disease (lung disease that affects the tissue around the lung's air sacs).
Diagnosis
Dermatomyositis is classified by a set of five criteria, which are divided into two groups.
The muscular symptoms include a progressive proximal symmetrical weakness (progressive weakening of muscles on both sides of the body), above-normal muscle enzyme levels, abnormal electromyography readings (measurements of the electrical activity in the muscles), and an abnormal muscle biopsy.
The cutaneous (skin) symptoms include skin disease, particularly on the nose and face in a butterfly pattern.
Complications
Possible complications of dermatomyositis may be due to involvement of vital organs and the skin. Muscle abnormalities may lead to difficulty swallowing, aspiration pneumonia (inflammation of the lungs and bronchial tubes from breathing in foreign substances), breathing problems, and digestive system ulcers. Skin complications may include calcium deposits and infections.
Having dermatomyositis makes patients more susceptible to several other conditions, including Raynaud's phenomenon, cardiovascular disease (including heart failure and heart arrhythmias), and cancer of the cervix, lungs, pancreas, breasts, ovaries, and gastrointestinal tract.
Dermatomyositis also increases the risk of still and premature births. The risk of pregnancy complications is reportedly lower when the disease is inactive, but it should still be discussed with a specialist if pregnancy is being considered.
Treatment
Nonpharmacological:
Bed rest is often helpful for sore or weakened muscles with severe inflammation. Physical therapy may prevent observable muscular symptoms and strengthen muscles.
Pharmacological: According to the Myositis Association, treatment of the muscular component of dermatomyositis includes immunomodulator drugs such as methotrexate, azathioprine, cyclosporine, cyclophosphamide, mycophenolate, leflunomide, and chlorambucil. Steroids have also been used, but side effects have limited their long-term use.
Other: Surgical options are lacking for this condition.
Integrative therapies
Unclear or conflicting scientific evidence:
Thymus extract: Thymus extract is of interest for treatment of dermatomyositis due to its role in stimulating the immune system. Additional research is needed in this area.
Avoid if allergic or hypersensitive to thymus extracts. Use bovine thymus extract supplements cautiously, due to the potential for exposure to the virus that causes "mad cow disease." Avoid use in those with an organ transplant or other forms of allografts or xenografts. Avoid in those receiving immunosuppressive therapy. Avoid in those with thymic tumors, myasthenia gravis (neuromuscular disorder), or untreated hypothyroidism, or those taking hormonal therapy. Avoid in pregnant or breastfeeding women. Thymic extract increases human sperm motility and progression.
Traditional or theoretical uses lacking sufficient evidence:
Krill: Krill has been used to treat dermatomyositis historically. However, high-quality research is needed in this area.
Use cautiously in people with bleeding disorders, low blood sugar, or low blood pressure, or those taking any agents to treat these conditions. Avoid in those with known allergy or sensitivity to seafood or shellfish.
Potentially harmful contaminants such as dioxins, methylmercury, and polychlorinated biphenyls (PCBs) are found in some species of fish. Unrefined fish oil preparations may contain pesticides. Use cautiously in patients with high blood sugar levels, bleeding disorders, diabetes, low blood pressure, high levels of LDL cholesterol, tachycardia (rapid heart rhythm), or arrhythmia (altered heart rhythm). Use cautiously in those at risk for hormone imbalance or those undergoing hormone replacement therapy. Use cautiously in patients with asthma, inflammatory bowel disease, or liver disease; in patients at risk for colon cancer; or in those using drugs or herbs or supplements that treat any such conditions. Use cautiously in pregnant or breastfeeding women. Fish oil taken for many months may cause a deficiency of vitamin E and may increase the risk of vitamin A or D toxicity. Use large amounts cautiously. Avoid in those allergic or hypersensitive to fish, nuts, omega-3 fatty acid products that come from fish or nuts, or linolenic acid.
PABA taken by mouth is generally well tolerated. Doses taken by mouth may need to be adjusted in patients with impaired kidney function. Pharmaceutical doses of PABA and its derivatives should only be taken under the supervision of a qualified healthcare provider. PABA given intravenously may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or those taking drugs, herbs, or supplements that may increase the risk of bleeding. PABA may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Use with caution in patients with kidney disease and when taking by mouth in doses greater than eight grams daily. Discontinue if rash, nausea, or anorexia occurs. Avoid in those taking sulfonamide antibiotics at the same time, as it may reduce their effectiveness. Avoid giving to children by mouth, due to an increased risk of serious side effects. Avoid in pregnant or breastfeeding women, due to a lack of available scientific evidence. Avoid in those with known allergy or hypersensitivity to PABA and its derivatives para-aminomethylbenzoic acid (PAMBA), butyl aminobenzoate (BAB), padimate O (octyl dimethyl PABA), potassium para-aminobenzoate (KPAB or POTABA?), N-benzoyl-L-tyrosyl PABA, Aktipol?, or ursodeoxycholic acid-PABA.
Physical therapy: Historically, physical therapy has been used to treat rheumatic diseases, such as juvenile dermatomyositis. Research is needed in this area.
Not all physical therapy programs are suited for everyone, and people should discuss their medical history with a qualified healthcare professional before beginning any treatments. Physical therapy may aggravate preexisting conditions. Persistent pain and fractures of unknown origin have been reported. Physical therapy may increase the duration of pain or cause limitation of motion. Pain and anxiety may occur during the rehabilitation of patients with burns. Both morning stiffness and bone erosion have been reported, although the cause of these symptoms is still unclear. Erectile dysfunction has also been reported. Physical therapy has been used during pregnancy, and although reports of major adverse effects are lacking, caution is advised. All therapies during pregnancy and breastfeeding should be discussed with a licensed obstetrician/gynecologist before initiation.
Thyme: Thyme has been used to treat dermatomyositis. Additional research is needed in this area.
Use cautiously in patients with diabetes, hypoglycemia, bleeding disorders, or blood pressure disorders, and in those taking drugs, herbs, or supplements for these conditions. Use cautiously in patients with gastrointestinal irritation or peptic ulcer disease. Use cautiously if driving or operating heavy machinery or if taking sedatives or central nervous system (CNS) depressants. Use cautiously in medicinal amounts in women who are pregnant or trying to become pregnant. Use cautiously in patients with thyroid or hormonal disorders (or those at risk for hormone imbalances) or in patients taking agents for these conditions. Use cautiously in patients taking agents metabolized by the liver's cytochrome P450 system, ciprofloxacin, salicylate-containing agents, or topical agents. Avoid in individuals with a known allergy or hypersensitivity to thyme, its constituents, members of the Lamiaceae (mint) family, or to rosemary (Rosmarinus officinalis). Avoid use on the skin in areas of skin breakdown or injury, or in atopic patients. Thyme oil should not be taken by mouth and should be diluted when applied on the skin.
Prevention
Dermatomyositis is thought to be genetic (inherited), and there are no known ways to prevent the condition. Individuals affected with skin symptoms of the disease should prevent excessive sun exposure by taking measures such as wearing protective clothing and high-SPF sunscreen when going outdoors.
Author information
This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Bibliography
Callen JP. Dermatomyositis. Lancet 2000 Jan;355(9197):53-7. .
Callen JP, Wortmann RL. Dermatomyositis. Clin Dermatol 2006 Sep-Oct;24(5):363-73. .
Choy EH, Hoogendijk JE, Lecky B, Winer JB. Immunosuppressant and immunomodulatory treatment for dermatomyositis and polymyositis. Cochrane Database Syst Rev 2005 Jul;CD003643. .
Konno T, Umeda Y, Umeda M, Kawachi I, Oyake M, and Fujita N. [A case of inflammatory myopathy with widely skin rash following use of supplements containing Spirulina]. [Article in Japanese]. Rinsho Shinkeigaku. 2011 May;51(5):330-3. .
Lee AN, and Werth VP. Activation of autoimmunity following use of immunostimulatory herbal supplements. Arch Dermatol. 2004 Jun;140(6):723-7. .
Marvi U, Chung L, Fiorentino DF. Clinical presentation and evaluation of dermatomyositis. Indian J Dermatol. 2012 Sep;57(5):375-81. .
National Institute of Neurological Disorders and Stroke. .
Natural Standard: The Authority on Integrative Medicine. .
Polsdorfer, R. "Dermatomyositis." .
PubMed Health. .
Seidler AM, Gottlieb AB, Dermatomyositis Induced by Drug Therapy: A Review of Case Reports, J Am Acad Dermatol. 2008 Nov;59(5):872-80. .
The Myositis Association "Types of Myositis." .
The National Organization for Rare Disorders. .
Zouagui A, et al. Actuality of Juvenile Dermatomyositis. Joint Bone Spine Volume: 78 Issue: 3 (2011-05-01) p. 235-240. .
Causes
The cause of dermatomyositis is unknown. Scientists believe that it is similar to other autoimmune diseases, where the immune system attacks normal components of the body.
Risk factors
Genetics may play a part in making a person more likely to develop dermatomyositis. Another theory links infectious viral agents, such as parvovirus and Epstein-Barr virus, to the disease. Case reports of dermatomyositis have linked breast implant surgery and collagen injections to disease flares. A possible link to statin drugs, penicillamine, quinidine, and phenylbutazone has also been reported. There are also several reports of individuals developing dermatomyositis after taking supplements that contained spirulina, a blue-green alga which may stimulate the immune system, and another case reported both development and a severe disease flare with the use of a supplement containing Spirulina plantesis.
Types of the disease
There are three forms of the disease, which vary in terms of the symptoms they commonly cause.
Childhood dermatomyositis:
Childhood dermatomyositis
most commonly occurs in children aged 5-15, and abnormal calcium deposits (also known as calcifications) in the muscles, skin, and digestive tissues are common.
Adult dermatomyositis: Adult dermatomyositis generally occurs in a person's late 40s to early 60s, and generally has a more gradual onset than the childhood version of the disease. Calcifications are less common in the adult onset form of the disease.
Dermatomyositis sine myositis: Dermatomyositis sine myositis results in skin symptoms, but none of the myopathic (muscular) symptoms.