Undifferentiated Seronegative Spondyloarthropathies
Seronegative spondyloarthropathies are characterized by sacroiliitis, spondylitis, peripheral arthritis or extraarticular manifestations like uveitis (eye inflammation). Seronegative means negative blood cultures (no bacteria found in the blood). The spondyloarthropathies are associated with a positive HLA-B27 (HLA stands for human leukocyte antigen) status. Genetic factors, repetitive biomechanical stress and the immune response to bacterial products lead to the inflammatory changes at large joints of the extremeities as wall as in the fingers. Diseases classified as spondyloarthropathies include ankylosing spondylitis, reactive arthritis, psoriatic arthritis, juvenile spondyloarthropathy and inflammatory bowel disease associated with spondylitis. The SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome is a member of the spondyloarthropathy family. An otherwise unclassified HLA-B27-linked peripheral arthritis is often considered an undifferentiated spondyloarthropathy. Treatment consists of physical therapy including patient education, non-steroidal anti-inflammatory drugs and anti-rheumatic drugs.