gattii was recorded from a Congolese Bantu boy with meningitis in 1970 ( 48). neoformans approximately 50 million years ago ( 112). Phylogenic studies showed a divergence of C. neoformans) have been recently described in patients with cryptococcosis without known risk factors ( 24, 73). Furthermore, autoantibody against GM-CSF ( C. Some cases occur in otherwise healthy patients with possible single-gene errors of immunity in the IL-12/IFNγ axis. Use of corticosteroids or others immunosuppressive drugs are frequently reported in association with others risk factors ( 122). Other predisposing factors such as solid organ transplant are listed in Table 2( 73). Nowadays, HIV represents the major risk factor (more than 50% of cases in the Western world while in Sub-Saharan Africa cryptococcosis is almost exclusively observed in HIV-infected patients). Patients with T-cell mediated immunodeficiency are at greatest risk for cryptococcal infections. Thanks to the introduction of highly active antiretroviral therapy (HAART), the rate of cryptococcosis has declined significantly in developed countries in the past few years with an increase of cryptococcosis in HIV-negative patients ( 131). However, this infection has emerged as a major cause of mortality among persons who do not have access to HAART in developing countries. One million cases are reported each year in Sub-Saharan Africa, with more than 600 000 deaths/year in HIV-infected patients ( 123). In 1990’s, 80% of cryptococcosis occurred in patients with AIDS ( 39).
With the emergence of AIDS, the yeast gained increasing medical importance. However, cryptococcosis was rare before 1980’s ( 36, 132). neoformans exposition is frequent as 80% of adults have antibodies directed against C. VGII genotype can be further divided into three subtypes: VGIIa, VGIIb, VGIIc. gattii can be divised into four genotypes: VGI, VGII, VGIII, VGIV. These species are characterized by distinct geographic distribution, host preference clinical presentation and therapeutic recommendations. C. neoformans variety grubii corresponds to serogroup A and C. neoformans variety neoformans is serogoup D ( Table 1) ( 24, 36). Two Cryptococcus species are pathogenic in humans: C. Polysaccharide capsule and melanin are virulence factors. Cryptococcus spp.is a basidiomycetous yeast.
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