As I was saying

Antibiotic exposure could increase the risk of juvenile arthritis

Previous studies indicate that about a quarter of antibiotics prescribed to children - and half of antibiotics prescribed for acute respiratory infections - are probably unnecessary.

Researchers began the study in 2014 because of previous studies showing that antibiotics could predispose children to develop other chronic diseases, including inflammatory bowel disease. Disruption of microbial communities in the intestines and elsewhere appears to play a role in inflammatory bowel disease and other autoimmune diseases, including rheumatoid arthritis in adults. "Antibiotics are one of the better known disruptors of human microbial communities," Horton noted.

Researchers also found that upper respiratory tract infections treated with antibiotics were more strongly associated with juvenile arthritis than untreated upper respiratory tract infections. Additionally, they noted that antiviral and antifungal drugs were not linked to juvenile arthritis, suggesting that risk for arthritis was specific to antibacterial medicines.

Abstract