Improved Visual Detection of speB Gene in Streptococcus pyogenes Isolates by Real-time Loop-Mediated Isothermal Amplification Turbidimetry Method

Background: Group A Streptococcus (GAS) causes a wide array of clinical manifestations ranging from mild pharyngitis to suppurative and non-suppurative severe debilitating diseases. Hence, simple, rapid detection method with high sensitivity specificity is needed. Objectives: This study embarked on the visual streptococcal pyrogenic exotoxin B (speB) gene by real-time turbidimetry loop-mediated isothermal amplification (RT-LAMP) methods. The monitoring sigmoidal graph generated was incorporated in assay. Methods: speB virtually observed (sigmoidal curve) via turbidimeter, thus providing “guide” accurately estimate time positivity for detection. Results: targeted detected at 15 min but optimally amplified within 45 an temperature 63°C 100% using established set primers. formation curves correlated other observations naked eye (from orange green), ultra-violet light (green fluorescence), agarose gel electrophoresis. improved limit RT-LAMP assay also compared conventional PCR (0.001 pg/µL versus 1 ng/µL). Conclusions: could provide additional insight rapid, cost-effective, reliable identification GAS low or middle-income countries. It be very important tool improve healthcare management patients infected future.