April 4, 2006
Early Diagnosis Important in Muscle Disorder
CHICAGO—Dermatomyositis, a rare, debilitating inflammatory disease, should be diagnosed and treated promptly in children, Northwestern University researchers recommend.
Dermatomyositis is an autoimmune disease in which the body’s immune system attacks muscle and skin, often causing an extensive rash, as well as progressive, severe muscle weakness, pain, and fatigue. Between 3,000 and 5,000 children in the United States have juvenile dermatomyositis.
The length of time that a child has been ill has a major impact on some of the criteria that physicians use to gauge the severity of juvenile dermatomyositis and the intensity of treatment,” said Lauren M. Pachman, MD, professor of pediatrics at Northwestern University’s Feinberg School of Medicine, who led the study.
“The lack of some of the criteria might lead to further delay in starting therapy or even inappropriate therapy for the severity of the real problem, Dr. Pachman said. “The consequence of this delay is often development of soft tissue calcification, which increases complications and death associated with this illness.”
Dr. Pachman is director of the Molecular and Cellular Pathobiology Program at Children’s Memorial Research Center and received the American College of Rheumatology Clinical Research Award in 2004.
She and colleagues examined the duration of untreated dermatomyositis symptoms in 166 children. The mean duration of untreated disease—defined as the time from first sign of rash or weakness to the diagnostic visit with a physician—was just over four months, they reported in the February issue of Pediatrics.
The researchers found that boys and girls with untreated juvenile dermatomyositis were significantly shorter and lighter in weight than national norms based on age and sex.
Growth impairment may be associated with juvenile dermatomyositisârelated inflammation of blood vessels, which can lead to a marked decrease in the body’s ability to absorb food and nutrients, the scientists suggested.
The researchers also observed a negative association between the duration of untreated juvenile dermatomyositis and weakness associated with disease activity. Non-white children were significantly weaker than white children, and older children were more likely to have difficulty swallowing and arthritis.
This study was supported by grants from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (N01-AR-4-2219), Juvenile Dermatomyositis Research Registry, Arthritis Foundation, Marlene Apfelbaum Foundation, Pappas Foundation, and National Institutes of Health (K24 02138).