Ann Lab Med.  2019 Jan;39(1):31-35. 10.3343/alm.2019.39.1.31.

Evaluation of the SD Bioline Strep A Ultra Test in Relation With Number of Colony Forming Units and Color Intensity

• Ma SH
• Choi WH
• Park H
• Kim S

• KMID: 2420268
• DOI: http://doi.org/10.3343/alm.2019.39.1.31

Abstract

BACKGROUND
The SD Bioline Strep A Ultra (SD, Yongin, Korea) is a recently developed rapid antigen detection test (RADT) for diagnosing bacterial pharyngitis caused by Group A Streptococcus, We evaluated the performance of SD Bioline Strep A Ultra, using the number of colony forming units and color intensity.
METHODS
Three throat swabs each were taken from 343 children with pharyngitis who visited pediatric clinics. We evaluated the performance of SD Bioline Strep A Ultra and compared its positive rate with the number of colony forming units, using the Fisher exact test.
RESULTS
The sensitivity, specificity, positive predictive value, and negative predictive value (95% confidence interval) were 97.4% (94.0-99.1%), 90.8% (85.0-94.9%), 93.0% (88.5-96.1%), and 96.5% (92.0-98.9%), respectively. Positive rate significantly differed by number of colony forming units (P=0.021). ROC plot for color intensity showed 0.938 of AUC (area under curve).
CONCLUSIONS
SD Bioline Strep A Ultra showed excellent performance, and its positive rate differed by the number of colony counts. This RADT could be used as a sensitive and semi-quantitative method detecting bacterial pharyngitis.

Keyword

Group A Streptococcus; Pharyngitis; Rapid antigen detection test; Evaluation

MeSH Terms

Area Under Curve
Child
Gyeonggi-do
Humans
Methods
Pharyngitis
Pharynx
Sensitivity and Specificity
Stem Cells*
Streptococcus

Figure

• 

  Fig. 1 ROC plot for color intensity of SD Bioline Ultra test.Abbreviation: CI, confidence interval.

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