IgA transglutaminase levels in children with Juvenile Idiopathic Arthritis.

OBJECTIVES

Several studies have indicated that adult patients with spondyloarthritis (SpA) have elevated levels of antibodies associated with celiac disease (CD). This has not been studied in children, and none of the studies corrected for total IgA levels.

METHODS

We measured total IgA and IgA against tissue transglutaminase (TTG) levels in 42 children with Juvenile Idiopathic Arthritis (JIA), of whom 11 had SpA, along with 10 non-inflammatory control subjects.

RESULTS

Median (IQR) TTG IgA levels were elevated among children with ERA (8.8, 4.6 - 21) compared to 'JIA controls' (JIA subgroups other than ERA) (2.8, 1.5 - 5.9) and a healthy non-inflammatory control group (1.5, 0.82 - 12), p = 0.017, Kruskal-Wallis. There was no correlation between TTG IgA levels and measures of disease activity or with medicine use. None of the children were diagnosed endoscopically with celiac disease. Patients with ERA likewise had elevated total IgA level compared to the other groups (p = 0.001), and total IgA levels correlated highly with TTG IgA (r = 0.599, p<0.001).

CONCLUSION

These findings suggest that elevations in TTG IgA may reflect increased polyclonal IgA production, rather than a specific intestinal inflammatory process.