PT  - JOURNAL ARTICLE
AU  - Lillemor Berntson
AU  - Ellen Nordal
AU  - Kristiina Aalto
AU  - Suvi Peltoniemi
AU  - Troels Herlin
AU  - Marek Zak
AU  - Susan Nielsen
AU  - Marite Rygg
AU  - for the Nordic Study Group of Paediatric Rheumatology
TI  - HLA-B27 Predicts a More Chronic Disease Course in an 8-year Followup Cohort of Patients with Juvenile Idiopathic Arthritis
AID  - 10.3899/jrheum.121257
DP  - 2013 May 01
TA  - The Journal of Rheumatology
PG  - 725--731
VI  - 40
IP  - 5
4099  - http://www.jrheum.org/content/40/5/725.short
4100  - http://www.jrheum.org/content/40/5/725.full
SO  - J Rheumatol2013 May 01; 40
AB  - Objective. We investigated associations of HLA-B27 with clinical manifestations and longterm outcome in a near population-based setting among patients with juvenile idiopathic arthritis (JIA). Methods. We studied clinical and serological data from 410 patients with HLA-B27 results among 440 prospectively collected patients with JIA with 8-year followup data in a Nordic database. The study was structured to be as close to a population-based study as possible. Results. HLA-B27 was analyzed in 93% of patients, and was positive in 21% of the cohort, in 18.4% of the girls and in 25.9% of the boys. Boys who were HLA-B27-positive had significantly higher age at onset compared to HLA-B27-negative boys and compared to both HLA-B27-negative and positive girls. This difference in onset age in relation to HLA-B27 was not found in girls. HLA-B27 was associated with clinical signs of sacroiliitis, enthesitis, and tenosynovitis in boys, but not in girls. After 8 years of disease, 46 children (11.2%) were classified as having enthesitis-related arthritis (ERA). Boys with ERA had clinical signs of sacroiliitis more often than girls with ERA. HLA-B27-positive children, as well as children with clinical signs of sacroiliitis, enthesitis, and hip arthritis, had higher odds of not being in remission off medication after 8 years of disease. Conclusion. In this near population-based Nordic JIA cohort we found significant differences between HLA-B27-positive boys and girls in age at disease onset, clinical signs of sacroiliitis, and ERA classification. HLA-B27 was negatively associated with longterm remission status, possibly because of its association with clinical disease characteristics, such as sacroiliitis, rather than being a general marker of persistent disease.