Affinity molecular assay for detecting Candida albicans using chitin affinity and RPA-CRISPR/Cas12a

Area of Science:

• Medical Diagnostics
• Molecular Biology
• Infectious Diseases

Background:

• Invasive fungal infections (IFIs) present a major health risk, causing significant illness and death in immunocompromised individuals.
• Timely and precise diagnosis is crucial for initiating effective antifungal therapies.
• Current diagnostic methods may lack the sensitivity or speed required for optimal patient management.

Purpose of the Study:

• To develop and validate a rapid, sensitive molecular diagnostic method for detecting invasive fungal infections.
• To assess the performance of the new method in clinical and simulated samples.
• To evaluate the potential utility of this technique in resource-limited settings.

Main Methods:

• A three-step molecular diagnostic approach combining affinity-magnetic separation (AMS) for fungal enrichment.
• Genomic DNA extraction using silicon hydroxyl magnetic beads.
• One-pot system for rapid detection, optimized for Candida albicans in blood and bronchoalveolar lavage (BAL) samples.

Main Results:

• The method detected as low as 30 CFU/mL of C. albicans within 2.5 hours, demonstrating ~100x greater sensitivity than microscopy.
• Clinical sample validation yielded 93.93% sensitivity and 100% specificity.
• Simulated tests confirmed high performance with 95% sensitivity and 100% specificity.

Conclusions:

• The developed rapid molecular diagnostic technique is highly sensitive and specific for detecting invasive fungal infections.
• This cost-effective method is suitable for resource-limited settings and offers rapid results.
• The platform is adaptable for species identification and antifungal resistance detection.