Rapid detection of Mycobacterium leprae RLEP by recombinase polymerase amplification: A pilot study

Area of Science:

• Microbiology
• Molecular Diagnostics
• Infectious Diseases

Background:

• Early leprosy detection is critical to prevent deformities and impairments.
• Delayed treatment of leprosy leads to severe health consequences.
• Current diagnostic methods may not be sufficiently rapid for field deployment.

Purpose of the Study:

• To develop and evaluate a rapid Recombinase Polymerase Amplification (RPA) assay for Mycobacterium leprae DNA detection.
• To assess the sensitivity and clinical performance of the RPA assay.
• To explore the potential of RPA as a field-friendly diagnostic tool for leprosy.

Main Methods:

• Developed an in-house Recombinase Polymerase Amplification (RPA) assay targeting a 175 bp RLEP amplicon.
• Analyzed RPA amplicons using agarose gel electrophoresis and SYBR Green I.
• Validated the assay using PCR-confirmed leprosy cases and clinical skin biopsy samples.

Main Results:

• The RPA assay detected Mycobacterium leprae DNA within 20 minutes at 39 °C.
• Analytical sensitivity was determined to be 0.5 cells/µl using purified M. leprae genomic DNA.
• The assay demonstrated potential for clinical application with 28 DNA samples from skin biopsies.

Conclusions:

• Recombinase Polymerase Amplification (RPA) offers a rapid and sensitive method for Mycobacterium leprae DNA detection.
• The developed RPA assay shows promise for a quick, accessible, and field-deployable diagnostic tool for leprosy.
• This assay can significantly aid in the early detection and management of leprosy, preventing long-term complications.