The influence of patient characteristics, disease variables, and HLA alleles on the development of radiographically evident sacroiliitis in juvenile idiopathic arthritis

Abstract

In the current study, radiographically evident sacroiliitis had developed in 6% of JIA patients after a median disease duration of 14.9 years. HLA-B27, absence of DPB1*02, late onset of disease, and early hip involvement were predictors of sacroiliitis.

Genetic association between juvenile rheumatoid arthritis and polymorphism in the SH2D2A gene

“…Overall, JRA patients carried significantly more frequent two copies of 'short' alleles (GA 13 and/or GA 16 ) compared to healthy controls (10% vs 6%; OR ¼ 1.9; 95% CI (1.1-3.5); P n ¼ 2 ¼ 0.04). Intriguingly, a higher frequency of individuals homozygous for GA and/or heterozygous for GA [13][14][15][16] was observed in patients carrying the DRB1*08 allele, the strongest risk factor in pauci-and poly-RF-negative JRA subgroups, 13 compared to those patients being negative for the DRB1*08 allele ( Figure 3); however, these differences did not reach statistical significance due to insufficient number of patients in each group. The SH2D2A gene is located on chromosome 1, and DRB1 is located on chromosome 6; thus alleles at these two loci are inherited independently of each other.…”

“…Hence, individuals being homozygous for 'short' alleles of this GA repeat in the SH2D2A gene promoter display reduced expression of TSAd in activated T cells. 7 Moreover, there is an increased frequency of 'short' alleles (GA 13 and GA 16 ) among patients with multiple sclerosis (MS), suggesting that the SH2D2A gene may contribute to the genetic susceptibility to develop this disease. 7 This study was aimed to assess whether polymorphism of the SH2D2A gene promoter is also associated with juvenile rheumatoid arthritis (JRA).…”

“…The frequency of the short GA 13 allele was significantly increased among JRA patients compared to the controls (0.098 vs 0.05; OR ¼ 1.8; P nc ¼ 0.0053; P n ¼ 8 ¼ 0.042; for correction numbers, see figure legends), whereas the frequency of the GA 16 allele did not differ among patients and controls. Since we previously observed that genotypes homozygous for the short GA 13 and GA 16 alleles or heterozygous GA 13 /GA 16 were associated to MS, we specifically examined these three genotypes in JRA patients. As can be seen from Figure 2, all the three genotypes were increased among the JRA patients, but only the heterozygous GA [13][14][15][16] genotype reached statistical significance (5% vs 1%; OR ¼ 3.9; 95% CI (1.4-11.6); P n ¼ 4 ¼ 0.036).…”

“…Since we previously observed that genotypes homozygous for the short GA 13 and GA 16 alleles or heterozygous GA 13 /GA 16 were associated to MS, we specifically examined these three genotypes in JRA patients. As can be seen from Figure 2, all the three genotypes were increased among the JRA patients, but only the heterozygous GA [13][14][15][16] genotype reached statistical significance (5% vs 1%; OR ¼ 3.9; 95% CI (1.4-11.6); P n ¼ 4 ¼ 0.036). Overall, JRA patients carried significantly more frequent two copies of 'short' alleles (GA 13 and/or GA 16 ) compared to healthy controls (10% vs 6%; OR ¼ 1.9; 95% CI (1.1-3.5); P n ¼ 2 ¼ 0.04).…”

“…The SH2D2A gene is located on chromosome 1, and DRB1 is located on chromosome 6; thus alleles at these two loci are inherited independently of each other. We therefore also compared patients carrying the DRB1*08 allele with the total group of healthy controls, and observed significant differences in the frequency of individuals being heterozygous for GA [13][14][15][16] (9% in patients vs 1% in controls; OR ¼ 7.6, 95% CI (2.2-26), P n ¼ 8 ¼ 0.008). When considering the three short genotypes as a group, a total of 16% in patients compared to 6% of the controls carried such genotypes; OR ¼ 3.2, 95% CI ¼ 1.4-6.9; P n ¼ 4 ¼ 0.016) (Figure 3).…”