Juvenile Dermatomyositis

Juvenile dermatomyositis (JDM) is a rare disease that causes inflammation of the blood vessels, muscles and skin. It affects about 3,000-5,000 kids in the United States. Most cases occur between the ages of 5 and 10. Girls are more likely than boys to get the disease. 

Inflammation of the blood vessels (vasculitis) causes the primary symptoms of JDM: Skin rash and muscle weakness.  

The first sign of JDM is usually a red or purplish rash. The rash will appear on: 

• Eyelids (one of the first signs). 
• Cheeks (one of the first signs). 
• Nails. 
• Elbows. 
• Knees. 
• Chest. 
• Back.  

Muscle weakness may begin at the same time as the skin rash or develop days, weeks or months after. Weakness occurs on both sides of the body and can make running, climbing stairs and rising from a seated position difficult. Body parts affected include 

• Neck.
• Shoulders.
• Back.
• Stomach.
• Upper arms.
• Thighs.  

Other signs of JDM may include 

• Falling more often.
• Weak voice (dysphonia).
• Problems swallowing (dysphagia).
• Muscle pain. 
• Hardened white lumps under the skin (calcinosis). 
• Feeling very tired or rundown (fatigue).
• Joint pain or stiffness.
• Spiking fever. 

Complications of JDM can happen if the disease is untreated or undertreated.  

• Joint Contractures. When muscles shorten, either from tissue scarring or in some cases calcium deposits (calcinosis), they can pull joints into a bent position. Daily stretching and physical therapy can prevent permanent damage from joint contractures.  
• Skin Ulcers. Poor circulation from blood vessel inflammation can cause painful, open sores on the skin.   
• Digestive Problems. Inflammation of the blood vessels in the intestinal tract can cause ulcers and other digestive issues. Stomach pain or blood in the stool requires an immediate call to the doctor.