Comparison of the RapidFor™ Strep A Rapid Antigen Test with the Culture Method in Throat Swab Specimens: A Prospective Diagnostic Accuracy Study: Comparison of the Rapid Antigen Test with Culture in Throat Swab Specimens

Aslı Karadeniz; Pınar Eker; Tuğba Erener Ercan

doi:10.28982/josam.8702

Authors

Aslı Karadeniz Department of Infectious Diseases and Clinical Microbiology, Maltepe University Faculty of Medicine, Istanbul, Türkiye https://orcid.org/0000-0003-3799-1090
Pınar Eker Department of Biochemistry, Maltepe University Faculty of Medicine, Istanbul, Türkiye https://orcid.org/0000-0001-6514-8047
Tuğba Erener Ercan Department of Neonatology, Maltepe University Faculty of Medicine, Istanbul, Türkiye https://orcid.org/0000-0001-8944-0659

DOI:

https://doi.org/10.28982/josam.8702

Keywords:

rapid antigen tests, throat culture, Group A streptococci

Abstract

Background/Aim: Group A beta-hemolytic streptococci (GAS) are among the most common bacterial causes of pharyngitis. Throat culture is the reference diagnostic method, whereas rapid antigen tests offer faster results. This study aimed to evaluate the diagnostic performance of the RapidFor™ Strep A Rapid Antigen Test compared with throat culture in throat swab specimens.

Methods: Throat culture and rapid antigen testing were performed on specimens from 322 patients aged 2 years or older who presented to Maltepe University Faculty of Medicine Hospital between March and May 2024 with suspected upper respiratory tract infection and for whom GAS testing was planned. A single throat swab was used sequentially for culture and rapid antigen testing. Demographic information was recorded, and sensitivity, specificity, and accuracy were calculated using throat culture as the reference method.

Results: Among the 322 patients evaluated, 74.84% were younger than 18 years. GAS was detected by culture in 97 patients (30.12%). Both tests were positive in 94 patients, both tests were negative in 225 patients, and culture was positive but the rapid antigen test was negative in 3 patients. No false-positive results were observed. Sensitivity, specificity, and accuracy were 96.91%, 100%, and 99.07%, respectively.

Conclusion: The RapidFor™ Strep A Rapid Antigen Test demonstrated high diagnostic performance relative to throat culture in this cohort and provided a rapid testing option.

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