Removing the tonsils of children with mild or moderate throat infections is more expensive and has fewer health benefits than simply watching and waiting, Dutch researchers said.

In a study involving 300 children aged 2 to 8 advised to have their tonsils out, those who avoided surgery had fewer annual visits to doctors and lower resulting medical costs due to fevers and throat infections.

Tonsils are masses of tissue at the back of the throat that trap bacteria and viruses a person may breathe in.

"Surgery resulted in a significant increase in costs without realizing relevant clinical benefit," Erik Buskens, an epidemiologist and colleagues at the University Medical Centre Utrecht in the Netherlands, wrote in the Archives of Otolaryngology - Head and Neck Surgery.

Tonsillectomy is one of the most frequently performed surgical procedures for children. Young patients have traditionally had their tonsils removed to relieve repeated throat infections and related fevers.

While doctors today carry out far fewer tonsil operations than in the past, the Dutch study provides evidence that many children who do have the procedure see little, if any benefit.

In their study conducted between 2002 and 2003, the team excluded children with frequent throat infections or those who had their tonsils removed because of sleep apnea.

The researchers asked parents to track their children's respiratory track symptoms, measure their temperatures daily and record any costs related to their care.

They found that annual costs among the group which did not have surgery was about 551 euro per year, about 46 percent less than the 803 euros for children who had their tonsils removed. The children who avoided surgery also had fewer fevers, throat infections and respiratory illnesses.

The researchers did not take into account costs borne by parents in the form of missed days from work or other expenses related to their children's illnesses.

And because the surgery is cheaper in the Netherland than in many other countries, the gap between costs and benefits in other Western nations is likely greater, they said.

"Compared with other Western countries, our cost estimates may be low," the researchers wrote. "In other settings, the cost-effectiveness would be further offset by more costly procedures."