Abstract / Summary
Abstract Background: Respiratory syncytial virus (RSV) and adenovirus are important causes of acute respiratory tract infections in children, but their clinical presentations often overlap with those of other viral and bacterial pathogens. Although the polymerase chain reaction (PCR) is the reference standard for diagnosis, rapid antigen tests may provide clinically useful results in emergency settings. This study evaluated the diagnostic accuracy of the RapidFor™ RSV/ADV Rapid Test Kit compared with multiplex PCR in pediatric patients with acute respiratory symptoms. Methods: This prospective diagnostic accuracy study included 302 children aged ≤ 18 years who presented to a pediatric emergency department with acute respiratory symptoms from February to May 2025. Two nasopharyngeal swabs were obtained from each participant. The RapidFor™ RSV/ADV Rapid Test Kit was performed immediately at the point of care, and multiplex real-time PCR served as the reference standard. Sensitivity, specificity, positive and negative predictive values, and Cohen’s kappa agreement were calculated. Diagnostic performance was also assessed by age group, and multivariable logistic regression was used to identify independent predictors of PCR-confirmed positivity for adenovirus and RSV. Results: Adenovirus PCR positivity was detected in 59 patients (19.5%), while RSV PCR positivity was detected in 58 patients (19.2%). The adenovirus rapid test showed a sensitivity of 98.31%, a specificity of 98.77%, a positive predictive value of 95.08%, and a negative predictive value of 99.58%. The RSV rapid test demonstrated similar performance, with a sensitivity of 98.28%, a specificity of 98.77%, a positive predictive value of 95.00%, and a negative predictive value of 99.59%. Agreement with PCR was excellent for both pathogens (κ = 0.958). RSV positivity was highest among infants younger than one year, whereas adenovirus positivity peaked in school-aged children. Conjunctival injection and fever were independent predictors of adenovirus positivity, while cough and age under one year independently predicted RSV positivity. Conclusions: The RapidFor™ RSV/ADV Rapid Test Kit demonstrated high diagnostic accuracy and excellent agreement with multiplex PCR for detecting adenovirus and RSV in children presenting to the emergency department. Its rapid turnaround and ability to detect both pathogens from a single sample may support timely clinical decision-making in pediatric acute care settings.