Enhanced Specificity in Colorimetric LAMP Assay for Sarocladium kiliense Detection Using a Combination of Two...

Area of Science:

• Medical Mycology
• Molecular Diagnostics
• Fungal Pathogenesis

Background:

• The genus *Sarocladium* includes medically significant fungi like *S. kiliense* and *S. strictum*, causing infections in diverse patient groups.
• Current diagnostic methods for *Sarocladium* species are limited, necessitating the development of rapid and specific detection tools.
• Accurate identification of *S. kiliense* is crucial for effective patient management and infection control.

Purpose of the Study:

• To develop and optimize a rapid, specific colorimetric loop-mediated isothermal amplification (LAMP) assay for the detection of *Sarocladium kiliense*.
• To address cross-reactivity issues in initial LAMP assay prototypes targeting *S. kiliense*.
• To evaluate the efficacy of additives in enhancing assay specificity and sensitivity.

Main Methods:

• Development of a colorimetric loop-mediated isothermal amplification (LAMP) assay targeting *S. kiliense* (SK-LAMP).
• Inclusion of pullulan (1% v/v) and tetramethylammonium chloride (TMAC, 0.03 M) as additives to mitigate non-specific amplification.
• Validation of the optimized assay for specificity against related fungal species and sensitivity.

Main Results:

• The optimized SK-LAMP assay successfully detected *S. kiliense* within a 45-minute reaction time.
• The addition of pullulan and TMAC effectively eliminated false-positive results from closely related fungal species.
• The assay demonstrated high sensitivity and specificity for *S. kiliense* detection.

Conclusions:

• The optimized colorimetric LAMP assay provides a reliable, rapid, and specific method for detecting *S. kiliense*.
• The strategy of using pullulan and TMAC additives enhances the specificity of LAMP assays for closely related fungal species.
• This advancement holds significant potential for improving the timely diagnosis and management of *S. kiliense* infections.