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Spondyloarthropathies in circumpolar populations of Chukotka (Eskimos and Chukchi): epidemiology and clinical characteristics.

OBJECTIVE
We sought to determine the prevalence of HLA-B27 and the prevalence and nature of spondyloarthropathies in the native residents of Eastern Chukotka, Siberia, Russia.


METHODS
We conducted a cross sectional study with medical examination and interview of 464 of 640 (72.5%) native residents of 2 Eastern Chukotka settlements, Sireniki and Novo-Chaplino.


RESULTS
Among them were 212 Eskimos, 98 Chukchi and 154 subjects of mixed race. There were 2 subjects (0.4%) with ankylosing spondylitis, 2 with Reiter's syndrome, 2 with undifferentiated spondyloarthropathy and 1 with late onset pauciarticular juvenile arthritis consistent with spondyloarthropathy. Four of the subjects were Eskimos, 2 were of mixed race, and 1 was Chukchi. We found a high percentage of HLA-B27 antigen in the population, 32% in the native population overall, and 40% among the Eskimos.


CONCLUSION
Our data complement other studies of circumpolar populations and reinforce the reported high prevalence of spondyloarthropathy and HLA-B27 among those people.