Elevated tissue transglutaminase antibodies in juvenile idiopathic arthritis children: Relation to neutrophil-to-lymphocyte ratio and disease activity

Background: Subclinical gut inflammation is described in juvenile idiopathic arthritis (JIA), so has joint involvement been related to celiac disease (CD). The well-known involvement of tissue transglutaminase (tTG) in the pathogenesis of CD stimulated progress in the field of autoimmune diseases. Aim of the work: To screen JIA children for tTG antibodies and to detect its relation to the neutrophil-lymphocyte ratio (NLR) and disease activity. Patients and methods: The study included 44 JIA children with 44 matched controls. All subjects had no GIT symptoms suggestive of CD. Disease activity was assessed using the juvenile arthritis disease activity score in 27 joints (JADAS-27). The tTG antibodies (IgA and IgG) were assessed. Results: The patients mean age was 12.5 ± 2.8 years and disease duration 5.01 ± 2.9 years; Female:Male 3.4:1. The mean JADAS-27 score was 12.6 ± 2.04. tTG antibodies were positive in 43.2% of the patients compared to 18.2% control (p = 0.01). Antibodies positivity was comparable according to gender and subtypes. The NLR in JIA children (1.62 ± 0.58) was significantly higher than in control (1.3 ± 0.5) (p = 0.006). Those with positive tTG antibodies had a significantly reduced body mass index (p = 0.02) and increased NLR (p = 0.02) compared to those with negative tTG. Only NLR and JADAS-27 would significantly predict antibodies positivity (p = 0.037 and p = 0.04, respectively). Conclusion: Increased tTG antibodies are frequent in JIA children raising the possibility of an associated subclinical CD. Markedly reduced BMI and increased NLR could forecast the presence of these antibodies. In addition to the JADAS-27, the NLR is a simple test that could predict this association and could be a useful biomarker.