The major obstacles preventing better diagnosis are clinical suspicion and test availability. Doctors and health professionals need education to consider a fungal diagnosis, and it is usually not clinically obvious. Many fungal diagnostic tests are insensitive, some are not specific and large parts of the world have none.
The largest problem for most of the global population is simply unavailability of testing. There are several interconnected reasons for this:
GAFFI has identified the following five priority diseases and will work with partners to provide reliable and affordable diagnostic testing:
Summary of current tests are shown here.
|Diagnostic||Ease of use||Equipment||Performance||Deficiencies|
|Cryptococcal antigen dipstick||Simple, quick,||No||High and definitive||None, although quantitation may require a separate test|
|Pneumocystis PCR||Moderate||Yes||High||Needs to be put on a low cost platformSimpler simple processing required.|
|Histoplasma antigen test||Moderate||Yes||High in AIDS||ELISA good, but a CDC test and not commercialised. Simple dipstick for urine would be better.|
|Aspergillus IgG||Moderate||Yes||Good, needs development||Multiple tests available, many with poor sensitivity. Not fully standardised or evaluated in low resource countries.Simple dipstick for blood would be much better. Article – 2015 Comparison of Aspergillus-specific IgG assays|
|Microscopy and culture||Difficult||Yes, simple||Moderate (slow), if staff well trained. Otherwise low.||Microscopy is highly skilled and a direct detection tool would be much superior.Culture is simple, but lab contamination problematic and culture interpretation difficult. PCR would be superior.|
Additional information, including manufacturers shown here.