Adenotonsillectomy is one of the most common pediatric operations in the United States. Parents often agree to it to break a cycle of throat and airway infections. A new study from South Korea points the other way.
Researchers at Sungkyunkwan University School of Medicine tracked 6,848 children who underwent adenotonsillectomy. They compared them with 34,240 matched controls at a 1:5 ratio by age and sex.
The surgery group had more hospital visits for both upper and lower respiratory tract infections in the years that followed, according to the study published in the Journal of Rhinology on July 31, 2026.
Pneumonia rates specifically were not significantly different between the two groups. The increase in lower respiratory infections appeared first in younger children and later in older ones.
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Boys had more lower respiratory infections in the first two years after surgery. Girls saw more influenza and pneumonia in years two and three. Children with no history of infections before surgery showed the biggest jump.
Why the tonsils may still matter
Adenotonsillectomy is often performed to reduce recurrent infections.
But the tonsils and adenoids sit at the entrance of the airway as part of Waldeyer's ring. This group of lymphoid tissues helps the immune system encounter and remember pathogens in early childhood.
A 2023 review of tonsil and adenoid physiology describes them as screening inhaled microbes and helping produce antibodies that contribute to immune memory.
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The Korean team is not the first to report a long-term signal. A 2018 paper in JAMA Otolaryngology-Head & Neck Surgery followed nearly 1.2 million Danish children out to age 30.
It found tonsillectomy was tied to a 2.72-fold increase in later upper respiratory tract disease risk.
What the guidelines say
The operation is still considered appropriate for specific problems, particularly obstructive sleep apnea.
For recurrent throat infections, the American Academy of Otolaryngology-Head and Neck Surgery guideline recommends watchful waiting.
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Surgery is reserved for children with at least seven throat infections in the past year, five per year for two years, or three per year for three years.
More than 500,000 tonsillectomies are performed each year in children younger than 15 in the United States, making it one of the country's most frequent childhood operations.
The Korean authors concluded that adenotonsillectomy may have limited effectiveness in preventing long-term respiratory infections and urged clinicians to weigh the potential benefits and risks in each pediatric patient.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.