Several alterations in immune responses contribute to the risk of recurrent group A streptococcus tonsillitis, researchers report.

Recurrent tonsillitis is a common indication for tonsillectomy, yet it remains unclear why some children get group A streptococcus (GAS) recurrent tonsillitis and others do not.

Dr Shane Crotty, from La Jolla Institute for Immunology and the University of California, and colleagues compared the immunological characteristics of 26 children with recurrent GAS tonsillitis and 39 control children without recurrent tonsillitis who were undergoing tonsillectomies.

Germinal centres in tonsils from children with recurrent tonsillitis had significantly fewer T follicular helper cells and B cells than those from the control children, the team reported in Science Translational Medicine.