About 50,000 adolescents and children in Germany suffer from juvenile idiopathic arthritis. Each year, 1,000 children in Germany develop the disease. “Idiopathic” means that the cause of the disease is unknown, and “juvenile” means that the onset of symptoms is before the age of 16. It is a particularly aggressive form of rheumatoid arthritis.
Course of juvenile idiopathic arthritis.
The chronic disease affects joints, tendons, and bursae, as well as internal organs, nervous system, and eyes. Its course is similar to that of rheumatoid arthritis in adults, except that the process of destruction of the joints begins much earlier. A particularly feared complication of juvenile idiopathic arthritis is AA amyloidosis, pathological protein deposition almost throughout the body. This can result in significant organ dysfunction and lead to kidney failure. The eyes of children are particularly at risk. In about ten percent of children with the disease, a rheumatic inflammation of the iris develops, which can lead to eye damage and even blindness.
Triggers of juvenile idiopathic arthritis.
Why young people develop juvenile idiopathic arthritis has not been clearly explained by medical science to date. Presumably, an inherited predisposition in combination with external factors leads to a so-called autoimmune reaction: the immune system mistakes the body’s own tissue for infectious agents (bacteria or viruses) and starts an inflammatory reaction. Recent research has shown that the cytokine tumor necrosis factor alpha (TNFa) triggers and intensifies chronic inflammation. Cytokines are messenger substances that control the body’s immune system defenses.
Recognize symptoms
Most commonly, juvenile idopathic arthritis affects the small joints of the hands and feet, and often elbows, shoulders, hips, knees, and ankles. Typical signs include painful swelling, effusion, tenderness, and limited range of motion. Tendon sheath and bursitis as well as conspicuous thickenings under the skin on the extensor side of joints, so-called rheumatic nodules, indicate an affection of the soft tissues in the locomotor system.
If internal organs and organ systems are affected, the body often reacts with high fever accompanied by skin rashes. Dry mucous membranes of the mouth and eyes, inflammation of the conjunctiva and cornea, enlargement of the spleen and liver, or swelling of lymph nodes are other typical symptoms.
Rheumatic pains occur mainly at rest. They are often most severe at night, culminating in pronounced morning stiffness, and improve with exercise. The child often tries to reduce joint pain by holding the joint in a resting position midway between flexion and extension. Loss of appetite. Weight loss, fatigue, listlessness, and depressiveness further affect those with the condition.