Is Antibiotic Exposure Associated With Newly Diagnosed Juvenile Idiopathic Arthritis, Pediatric Rheumatologist Viewpoint.

In this nested case-control study in a populationrepresentative medical records database from the United Kingdom, children with newly diagnosed juvenile idiopathic arthritis (JIA) were compared with ageand gender-matched control subjects randomly selected from general practices containing at least one case, excluding those with inflammatory bowel disease, immunodeficiency, or other systemic rheumatic diseases. Conditional logistic regression was used to examine the association between antibacterial antibiotics (including number of antibiotic courses and timing) and JIA after adjusting for significant confounders. Any antibiotic exposure was associated with an increased rate of developing JIA [adjusted OR 2.1 (95% CI 1.2, 3.5)]. This relationship was dose dependent [adjusted OR over 5 antibiotic courses 3.0 (95% CI 1.6,5.6)], strongest for exposures within 1 year of diagnosis, and did not substantively change when adjusting for number or type of infections. In addition, antibiotic-treated upper respiratory tract infections were more strongly associated with JIA than untreated upper respiratory tract infections. The authors concluded that antibiotics were associated with newly diagnosed JIA in a doseand time-dependent fashion. Antibiotic exposure may play a role in JIA pathogenesis, perhaps mediated through alterations in the microbiome.