Scientists say they’ve made a huge leap in the understanding of the genetics of juvenile idiopathic arthritis, adding 14 more genes to the three previously known to be associated with the condition. Looking at patients from more than 40 pediatric practices and clinics in the United States and Europe, the study helped bring into focus the autoimmune aspects of juvenile arthritis and potential ways to refine the way the illness is treated.
There are 50,000 children in the U.S. who have one of the various varieties of juvenile arthritis, making it the most common rheumatic childhood disease in the country. They experience joint pain and stiffness, especially when getting up in the morning or after a nap, and swelling of the knees and other joints. Left untreated, it can lead to poor bone development and have adverse effects on growth. Juvenile arthritis is also linked to an eye inflammation called uveitis, which doesn’t always have symptoms itself but can result in various vision problems later in life, from cataracts and glaucoma to total blindness.
These findings will help us understand how the long suspected genetic contributions to JIA are driving the disease process, with the ultimate goal being earlier and improved diagnosis and treatment, said pediatric rheumatology expert Dr. Susan Thompson in a statement. Dr. Thompson was one of the lead researchers on the study. A greater understanding of the genetics of juvenile arthritis is only part of understanding the causes, which have historically proven difficult to pin down; mos likely, genetics combine with environmental triggers to cause the condition to develop.
Like other autoimmune diseases, juvenile arthritis is treated with anti-inflammatory drugs and immune suppressants, though special care must be taken to not interfere with the child’s physical development—corticosteroids, for example, are sometimes prescribed, but can themselves stunt a child’s growth. Sometimes, anti-inflammatories are supplemented by disease-modifying anti-rheumatic drugs such as methotrexate, though these can be harmful to a child’s liver. Regular exercise and a healthy diet can help control flare-ups, and applying cold or heat to swollen or achy joints can reduce symptoms.