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Retrospective study of juvenile spondylarthropathies in Croatia over the last 11 years.

OBJECTIVES
To determine the frequency of juvenile spondylarthropathies (JSpA) among other rheumatic diseases in a pediatric clinic population in an 11-year period in Croatia and to review their clinical, epidemiological, radiographic and laboratory.


METHODS
Of the 1264 patients with rheumatic diseases seen at a pediatric rheumatology center, 103 (8.2%) were diagnosed as having JSpA (56 boys, mean age 13.1 years, range 4.4-17.8 years), following the strict criteria of the European Spondylarthropathy Study Group. Medical history, clinical laboratory and imaging data of the 103 patients with JSpA were analyzed.


RESULTS
Eighty-two (79.6%) patients had undifferentiated spondylarthropathy, 6 (5.8%) patients had reactive arthritis/Reiter's disease, 6 (5.8%) had arthritis associated with inflammatory bowel disease, 5 (4.9%) had psoriatic arthritis, and only 4 (3.9%) patients had ankylosing spondylitis. The most common symptoms at the disease onset in patients with JSpA were peripheral and axial arthritis, followed by enthesitis. A significant increase in the number of patients with axial arthritis, peripheral arthritis, ocular symptoms and enthesitis was found during mean period of follow-up of 6.45 years. HLA-B27 was present in 78 (75.7%) patients.


CONCLUSION
In our hospital population the frequency of JSpA among other rheumatic disease was 8.2%. The disease was equally distributed among male and female patients, with onset around the age of 13 years. Most of the patients were diagnosed with undifferentiated spondylarthropathy.