Simple PCR-based DNA microarray system to identify human pathogenic fungi in skin

Area of Science:

• Medical Mycology
• Molecular Diagnostics
• Infectious Diseases

Background:

• Fungal infections in immunocompromised patients are a major health concern.
• Accurate and rapid identification of fungal pathogens is crucial for effective treatment.
• Current diagnostic methods like culture and morphology have limitations in speed and accuracy.

Purpose of the Study:

• To develop a simultaneous detection system for 26 clinically significant fungi.
• To establish a rapid and accurate diagnostic method for fungal identification directly from clinical specimens.
• To evaluate the performance of the developed assay in diagnosing onychomycosis.

Main Methods:

• Developed a Polymerase Chain Reaction and DNA microarray assay (PCR-DM).
• Utilized the internal transcribed spacer region of the rRNA gene for PCR amplification.
• Employed species-specific probes on a DNA microarray fabricated with Bubble Jet technology.
• Applied the PCR-DM assay to microscopy-confirmed onychomycosis specimens.

Main Results:

• PCR-DM successfully identified all 26 reference fungal strains.
• The assay detected fungal DNA and identified pathogens in 92% of 106 onychomycosis specimens.
• Culture methods were successful in only 34% of cases, with some discordant results later confirmed by PCR-DM.

Conclusions:

• PCR-DM offers a sensitive, rapid, and accurate method for identifying pathogenic fungi directly from tissue.
• This diagnostic approach has significant potential for clinical applications in various infectious diseases.
• The technology could be extended to detect other fungal or nonfungal pathogens in challenging anatomical sites.