Efficacy of Rapid Antigen Test and McIsaac / Modified Centor Scores for Diagnosis of Streptococcal Tonsillopharyngitis in Children

Objective: We aimed to determine the efficacy of rapid antigen tests, clinical signs, and McIsaac / modified Centor clinical scoring systems in the diagnosis of Group A streptococcus (GAS) at children. Materials and Methods: Subjects aged 3-14 years who presented with acute tonsillopharyngitis were questioned about their sociodemographic properties and symptoms. Their clinical signs and McIsaac / modified Centor scores were recorded. They underwent a rapid streptococcal antigen test and throat culture sampling. Results: GAS proliferated in culture %11 of cases. The risk of culture positivity was 4.8 times greater in children aged 6 years or older. There was a significant correlation between culture positivity and muscle pain, tonsillar edema. Rapid strep test had a sensitivity of 75% and a specifity of 100% for the diagnosis of streptococcal tonsillopharyngitis. Rapid strep test showed a sensitivity of 80% and a specifity of 100% in children with a McIsaac / modified Centor score of 4-5. Conclusions: Unnecessary antibiotic use for tonsillopharyngitis is an important problem. Therefore, it is ideal to order throat culture and act accordingly in every case suggesting GAS infection. However, when culture is not possible, rapid strep testing and McIsaac / modified Centor scoring are effective in guiding diagnosis and treatment.