G. S. Bushar1 , R. Shively2 , S. C. Wood1 , M. M. Lightfoote1 , 1CDRH, FDA, Silver Spring, MD, 2CDRH, FDA, Rockville, MD
Introduction
"Strep Throat", a common childhood disease, is caused by bacteria from Streptococcus Group A.While the disease can be treated readily with antibiotics, when left untreated, it Qualitative Analysis of Sensitivity of Streptococcus Group A Rapid Antigen Detection could cause serious consequences.In the past, cultivated bacteria in a blood agar plate was the only method, but that assay could take 24 - 48 hours to develop.Currently, there are many Rapid Antigen Detection Test (RADT) kits on the market.The purpose of this project is to provide an objective analysis of the sensitivity of five test kits.
Material and Method
We chose three test kits with dip sticks and two with cassettes from different manufacturers.We purchased the same strain of Streptococcus Group A culture that all five test kits use as positive control as our common antigen.We followed the package inserts from each manufacture for the testing method.All measurements were read by BioDot strip reader.
Results
All five test kits have clear and easy to follow instructions.We had found that visual observation is about as sensitive as machine reading, and all five test kits have about the same sensitivity within three fold of each other in titration.
Future Study
We plan to compare these test kits using the purified carbohydrate antigen to get a more quantitative analysis of the sensitivity.