Juvenile dermatomyositis (JDM) is a chronic, systemic connective tissue diseases In children (before the age of 16). Rheumatic inflammation of the skin and muscles results in characteristic symptoms. Special blood tests usually show typical signs of the disease. Dermatomyositis in children has a different disease course than dermatomyositis in adults.
Symptoms of juvenile dermatomyositis
Tiredness and fatigue along with muscle weakness are common symptoms
- Muscle pain may occur, but not in all cases
- Thigh muscles are most commonly attacked
- Symptoms may be trouble getting up from the floor or the chair, climbing stairs and hills
- Skin symptoms are often typical with red-blue-purple staining and some swelling over the stretch side of the knuckles on the hands (Gottron's sign / papels) and at the extensor side of elbows and knees. Some children get purple upper-eyelid discoloration (Heliotropic eczema)
- Calcium (calcinosis) under the skin is characteristic, but does not occur in all (10-30%)
- The areas around the eyes can also swell
- Some get dry cough and heavy breathing if exerted if the lungs are also attacked
Juvenile dermatomyositis (JDM = diagnosed on the basis of symptoms and examination findings.
- Muscle strength can be tested, often by experienced physiotherapists
- Blood tests often show elevated CK (muscle enzyme creatine kinase). Some have typical antibodies that include ANA (antinuclear antibody) With special subgroups
- Muscles are often examined MR which may show signs of inflammation
- Muscle tissue test (most often from thighs) is applicable to ensure the diagnosis and show the rate of inflammation
- CT of lungs are done to determine whether the lungs are attacked
Other muscular diseases with increased CK in children:
- Muscular dystrophies are also discussed on a separate page here
- Becker's muscular dystrophy
- Milder form, similar to Duchennes muscle dystrophy (see above)
- Duchenne muscular dystrophy
- The most common muscular disease in childhood
- Inherited X-bound (boys)
- Disease start most often at the age of 2-3
- The boys can not run
- Thickening of calves muscles
- Dystrophy myotonica
- Reduced ability to relax muscle
- Often cognitive changes (attention, memory, concentration)
- Emery-diffusible muscular dystrophy
- Often X-bound (boys)
- Contractions in elbows and stiffness in the back
- Increased physical fatigue
- Gradual development during childhood
- Shoulder-hip muscular dystrophies
- About 30 subgroups
- Muscular weakness in the shoulders and hips
- Spinal muscle atrophy
- Becker's muscular dystrophy
Atypical myocyte, fever episodes, elevated CRP over time, livedo reticularis, stroke also consider:
- Antifosfolipid syndrome
- Behcet's disease
- DADA2 (reference: Uettwiller F, 2016)
- Mitochondrial Disease
- Mitochondrial myopathy, encephalomyopathy, lactate acidosis, stroke-like symptoms (MELAS)
- Myoclonic Epilepsy with Ragged Red Fibers»(MERRF)
- Ragged Red Fibers are clumped diseased mitochondria in tissue sample (biopsy)
- Shortness of breath, hearing loss, lactate acidosis, intolerance to physical exercise
- Wilson's disease
There is no increased incidence of risk of cancer disease in children with JDM. This distinguishes JDM from dermatomyositis in adults.
Unknown. Heredity is rare and no infection or triggering environmental factors have been detected.
Very rare disease.
- One sees only a few new cases in Norway each year
Medications for juvenile dermatomyositis are important to fight the rheumatic inflammation initially and to keep the disease under control throughout the course. Often, the inflammation stops within a few years, but treatment and follow-up over several years is necessary.
- Medicinal treatment with cortisone in the form of Prednisone tablets combined with other immunosuppressive drugs are usually required. The cortison dose may often be high initially, but the dose is gradually reduced. Side effects include weight gain and growth reduction, but are transitory. Other medicines with minor side effects may take over for cortisone later in the course of the course: Methotrexate, Azathioprine and others. Against calcinosis (calcium under the skin) no drugs have shown safe effect.
No studies indicate that a particular diet or supplements of vitamins, trace elements or otherwise have an effect on juvenile dermatomyositis.
- In long-term illness and treatment, regular meals with a well-balanced diet are important to prevent a lack of proteins, vitamins, lime and other minerals. During Prednisolone (cortisone) treatment, supplementation of lime and Vitamin D to reduce the risk of osteoporosis (osteoporosis.).
- More on Diet in rheumatic disease here (in Danish) (Bindevevssykdommer.no)
- Differential Diagnostics Aden P, 2017 (Musculoskeletal Disease Disorders)
- Grans Compendium in Rheumatology