Direct Detection of Cryptococcus DNA from Tissues

Cryptococcus is a genus of fungus of which Cryptococcus neoformans is the most medically important species that primarily affects immunocompromised individuals. More recently genetic evidence for two distinct species, Cryptococcus neoformans and Cryptococcus gattii has been reported among strains of C. neoformans. C. gattii can infect even non-immunocompromised individuals and has been recognized as an emerging pathogen in US Northwest and adjoining Canadian state of British Columbia. It is therefore critical to correctly identify the exact type of C. neoformans to completely understand a given case of cryptococcal infection. Histology (mucicarmine stain), serology and culture are routinely used for a diagnosis. However, culture is not always successful or not possible in many cases where histology suggests the presence of Cryptococcus. PCR can be particularly useful in such cases to confirm or rule out a Cryptococcus neoformans infection and also determine the exact species i.e. C. neoformans or C. gattii.

Cryptococcus PCR detects Cryptococcus neoformans and Cryptococcus gattii with higher specificity and sensitivity than the broad-range fungal PCR. The analytical sensitivity is 1 genome per PCR reaction.

Heitman et al. (2005) Deciphering the model pathogenic fungus Cryptococcus neoformans Nature Reviews Microbiology, 3, pp 753