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 LFAs||Simple, quick,||No||High and definitive||Double positive titre (> 1:160)Usually associated with meningitis|
|Pneumocystis PCR||Moderate||Yes||High||Needs to be put on a low cost platform. Simpler simple processing required.|
|Histoplasma antigen test||Moderate||Yes||High in AIDS||ELISA good, New LFA in clinical validation|
|Aspergillus IgG||Moderate||Yes||Good, needs development||Multiple tests available, some with limited sensitivity. Not fully standardised or evaluated in low resource countries. Simple dipstick for blood would be much better. Comparisons published.|
|Microscopy and culture||Difficult||Yes, simple||Moderate (slow), if staff well trained. Otherwise low.||Microscopy requires skill. and a direct detection tool would be much superior. Culture is simple, but lab contamination problematic and culture interpretation difficult. PCR or antigen tests would be superior.|
Additional information, including manufacturers shown here.