In Spine Disease, Family Also at Risk
Written by Editor   
Monday, August 01, 2016 07:30 AM

Among seemingly healthy first-degree relatives of patients with ankylosing spondylitis, one-third actually fulfilled classification criteria for spondyloarthritis. Early diagnosis of spondyloarthritis has been hampered by the disorder’s insidious onset and slow progression, which often has resulted in delays in treatment and structural damage.  Studies have demonstrated an increased risk for spondyloarthritis among relatives of patients with ankylosing spondylitis — the prototypical subtype of spondyloarthritis.  Those studies have suggested that 10% to 12% of first-degree relatives of patients with ankylosing spondylitis develop the disease themselves, and that the risk is two-fold higher in HLA-B27 positive patients.

In a group of 51 first-degree relatives of 36 probands with ankylosing spondylitis, 17 (33%) met the criteria for spondyloarthritis established by the Assessment of Spondyloarthritis International Society (ASAS) or the European Spondyloarthropathy Study Group (ESSG).

The ASAS criteria include sacroiliitis visible on imaging, HLA-B27 positivity, inflammatory back pain, arthritis, enthesitis, dactylitis, psoriasis, good response to nonsteroidal anti-inflammatory drugs, family history of spondyloarthopathy, and elevated C-reactive protein. The ESSG criteria require inflammatory spinal pain or synovitis plus radiographic abnormalities, family history, or related disorders such as psoriasis and inflammatory bowel disease.

Among the first-degree relatives, 16% of those who did not meet the classification criteria had imaging abnormalities typical of spondyloarthritis such as bone marrow edema of the sacroiliac joints visible on MRI.