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Background

The diagnostic tools currently employed to detect fungal pathogens:

The diagnostic methods employed to diagnose fungal infections at present vary in performance as each type of pathogen has a greater proclivity for being detected by some tests than others. However, microscopy has always been the mainstay as far as diagnosis of fungal infections is concerned. We look forward to improve the diagnostic capabilities of conventional microscopy by enhancing specificity and visibility through the application molecular biology.The following table was compiled from Fungal Infection Thrust.

Detection by Polymerase Chain Reaction

The table above denotes a summary of the techniques used at present to detect the leading fungal pathogens in world. Note that the column titled "DNA detection" is a term that mainly involves the use of the Polymerase Chain Reaction (PCR)to detect pathogens. Although it is touted as a reliable technique, it has several disadvantages such as high cost, requirement of laboratory settings of high standards and false positives due to detection of pathogenic DNA EVEN AFTER the resolution(clearance) of the disease. Finally, PCR amplifies the DNA in a sample and only gives qualitative results. While Real-Time PCR can give information on the initial amount of the sample, it requires RNA samples which are degraded by RNases in the body and even if it isn't, it requires a well equipped laboratory to prevent further degradation.Therefore, this method cannot be used reliably in many parts of the world (especially in the underdeveloped countries).

Another technique that can be used to detect pathogens through their DNA is DNA-hybridization, but the downside with this method is that it is labor intensive and involves the use of radio-labelled probes.

Detection by Microscopy

As mentioned before, microscopy has been the mainstay for detection of pathogenic fungi. This is primarily due to the fact that it's one of the oldest and most widely available means of detection. It only requires a microscope, a stain for contrast, the sample from a patient and a user with some experience. Furthermore, this technique requires neither the consideration of multiple parameters (such as in a PCR) nor much time (agar plate cultures need at least a day) to yield results.

Thus, we believe that improving detectability through microscopy by giving it the advantage of molecular biology (specificity and a better scope for visualization) while maintaining the advantages of conventional microscopy.

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