Juvenile ankylosing spondylitis refers to ankylosing spondylitis that develops when the age is less than 16 years old. The onset of the disease is different from that of adults with lower back stiffness, difficulty getting up in the morning, painful rest, and limited movement of the lower back.
Monoarthritis of the lower extremities refers to unilateral ankle-knee and hip arthritis, with unilateral knee arthritis being the most common. If male young children present, if no systemic symptoms, and non-trauma caused, with a family history of ankylosing spondylitis, to first consider ankylosing spondylitis, the examination should be around the sacroiliac joint, CT examination is preferred, because ordinary X-ray, is not sensitive to early lesions. ct is still doubtful, check HLA-B27 to help diagnose. Wang Zhankui, Department of Rheumatology and Immunology, Shandong Province Qianfo Mountain Hospital
Do not treat it as rheumatoid, rheumatic fever and traumatic synovitis diagnosis, just around the knee joint examination, or just check rheumatoid factor, C-reactive protein, once you see a positive anti-O, you think it is rheumatic fever, and blindly apply antibiotics in high doses for a long time.