Streptococcus Pyogenes. Photo:BSIP/UIG Via Getty Images
Scientists may have discovered one of the mysterious reasons behind why some children have recurrent tonsillitis (RT) when they have a strep infection, finding there may be a genetic predisposition in some people, according to a study published in Science Translational Medicine Wednesday.
Why it matters: There are an estimated 600 million cases of strep globally and 750,000 tonsillectomies performed in the U.S., mostly caused by RT. It can greatly disrupt children's education, force parents to miss work, and in developing countries without large amounts of antibiotics, it can lead to dangerous acute rheumatic fever or rheumatic heart disease.
What they did: Over a 7-year period, the team collected and tested tissue samples from tonsils and blood tests from 66 children with RT and 80 children with sleep apnea (as a control group).
What they found: Children with RT had smaller germinal centers in their tonsils with fewer key immune cells (called GC-Tfh). Plus, their blood tests showed much lower antibodies to the strep bacteria Streptococcus pyogenes (group A Streptococcus, or GAS) in their blood, study author Shane Crotty tells Axios.
- They also identified two variations in genes associated with RT.
- "That is relevant for clinical practice as well as interesting from an infection biology perspective. Their results indicate that some children are genetically more prone to get recurrent GAS tonsillitis, and they shed light on both the genes and the biological mechanisms involved," says Georgia Institute of Technology's Kristofer Wollein Waldetoft, who was not part of this study.
- "The study does suggest something is different about the immune response of children labelled as having recurrent tonsillitis, and further study might clarify the exact components of this immune response that would then guide streptococcal vaccine development," Children's National Health Systems' Bernhard L. Wiedermann, who was not part of this study, tells Axios.
Yes, but: Wiedermann points out "the study lacks sufficient detail about the children’s clinical data [like precision of strep diagnostics]. Plus, the number of children studied is very small, making it difficult to generalize these findings to children in the U.S. or elsewhere."
What's next: Crotty, who's a professor at La Jolla Institute for Immunology and at UC San Diego, agrees that this small study is a first step.
- Crotty says they are encouraging larger, multi-institutional studies to be conducted to validate the findings in different locations.
- After that, they hope to develop a diagnostic test, which could immediately indicate if a child should have their tonsils removed or not, and perhaps lead to a vaccine later down the road, he adds.
- "It could be a first step towards diagnostics, and I’d hope that it could eventually lead to the development of other interventions than tonsillectomy," Wollein Waldetoft tells Axios.