Association of HLA-B27 antigen with clinical and laboratory parameters in patients with juvenile idiopathic arthritis.

Aim To analyse the association of human leukocyte antigen B27 with clinical and laboratory parameters in patients with juvenile idiopathic arthritis (JIA) at the disease onset. Methods A retrospective review of medical records of 25 HLAB27 positive and 25 HLA-B27 negative JIA patients was performed. The diagnosis of JIA was based on the 1997-2001 International League Against Rheumatism (ILAR) criteria. Collected data: age, sex, HLA- B27 antigen presence, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid-factor (RF), antinuclear antibody (ANA), fever, rash, uveitis, enthesitis, inflamed joints and subtype of JIA. Results HLA- B27 positive study group had more boys (p=0.01), higher erythrocyte sedimentation rate (p=0.038), higher presence of fever (p= 0.025) and enthesitis (p=0.024). Any significant difference in age of the disease onset, CRP, ANA, RF, rash, uveitis, inflamed joint and dactylitis was not noticed. The most common subtype of JIA in the HLA-B27 positive patients was ERA (60%). Conclusion This study showed that the presence of HLA- B27 antigen plays a significant role in determining the presenting clinical and laboratory characteristics in JIA patients.