Comparison of the Clinical Performance of Binax NOW RSV Versus Multiplex RT-PCR for Detection of Respiratory Syncytial Virus

ABSTRACT

BACKGROUND: Respiratory syncytial virus (RSV) is one of the most important causes of lower respiratory tract infection. The rapid antigen test is a simple, cheap, and quick method for RSV detection, however, it has an acknowledged low sensitivity. The aim of this study is to evaluate the diagnostic performance of the rapid antigen test by comparing it with a multiplex reverse transcription-PCR (RT-PCR). METHODS: A total of 557 nasopharyngeal aspirates or swabs that were submitted for both a rapid antigen test, Binax NOW RSV (Binax; Alere Scarborough, Inc., USA) and multiplex RT-PCR, Seeplex RV7 (Seegene Inc., Korea) were included in this study. We performed both tests according to the manufacturer's recommendations and analyzed the diagnostic performances of a rapid antigen tests based on the results of multiplex RT-PCR. RESULTS: Among the 557 specimens, the positive rates determined from the rapid antigen test and multiplex RT-PCR were 12.2% (N=68) and 25.1% (N=140), respectively. The relative sensitivity and specificity of the rapid antigen test were 46.4% and 99.3% based on the multiplex RT-PCR, respectively. Positive and negative predictive values were 95.6% and 84.7%, respectively. The diagnostic sensitivity was lower (28.6%) in children >36 months compared with children < or =36 months of age. Test sensitivity declined when RSV infection was accompanied by infection with other respiratory viruses. CONCLUSIONS: Binax NOW RSV exhibited good diagnostic performance, easy handling, and rapidity. However, it does have the possibility of false-negative results, and additional tests are needed when there is clinical suspicion of RSV infection.