Cryptococcosis is an important fungal infection in immunocompromised individuals, especially those infected with HIV. In Brazil, despite the free availability of antiretroviral therapy (ART) in the public health system, the mortality rate due to Cryptococcus neoformans meningitis is still high. To obtain a more detailed picture of the population genetic structure of this species in southeast Brazil, we studied 108 clinical isolates from 101 patients and 35 environmental isolates. Among the patients, 59% had a fatal outcome mainly in HIV-positive male patients. All the isolates were found to be C. neoformans var. grubii major molecular type VNI and mating type locus alpha. Twelve were identified as diploid by flow cytometry, being homozygous (AαAα) for the mating type and by PCR screening of the STE20, GPA1, and PAK1 genes. Using the ISHAM consensus multilocus sequence typing (MLST) scheme, 13 sequence types (ST) were identified, with one being newly described. ST93 was identified from 81 (75%) of the clinical isolates, while ST77 and ST93 were identified from 19 (54%) and 10 (29%) environmental isolates, respectively. The southeastern Brazilian isolates had an overwhelming clonal population structure. When compared with populations from different continents based on data extracted from the ISHAM-MLST database (mlst.mycologylab.org) they showed less genetic variability. Two main clusters within C. neoformans var. grubii VNI were identified that diverged from VNB around 0.58 to 4.8 million years ago.

Nearly one million of cryptococcosis cases occur yearly around the world, involving mainly HIV-infected patients who are not receiving antiretroviral therapy (ART) or present poor adherence. This study aims to evaluate epidemiological, clinical and outcome aspects of patients with cryptococcosis from 1998-2010. Patients were prospectively recruited, and their medical and laboratory records were reviewed. A total of 131 cases were included, and of these, 119 (90.83%) had AIDS, 4 received a renal transplant, 2 presented systemic lupus erythematosus and 6 (4.6%) were apparently immunocompetent. Ninety-one (69.46%) were men, and the median age was 38.7 years. Cryptococcal meningitis (CM) was diagnosed in 103 (78.62%), whereas 28 (21.38%) had cryptococcal infection in other sites. Of patients with CM, 94 (91.26%) had AIDS being cryptococcosis the first defining illness in 61 (64.9%), while 37 (60.65%) of them presented simultaneously both diagnosis. Headache, altered mental status, papilledema and seizures at admission were significatively associated with a poor outcome. Of 163 different isolates, 155 (95.09%) were Cryptococcus neoformans and eight (4.88%) Cryptococcus gattii. Antifungal therapy was warranted in 8 (87.4%) patients with CM, but 46 (51.1%) died during the first days or weeks. Of 28 patients without CM, 21 (75%) received treatment, but 6 (28.6%) died. The poor outcome among this case series was similar to that reported from other developing countries, but it is paradoxal in Brazil where the ART is at free disposal in the public health services. Despite, at least 60-70% of patients present advanced immunosuppression when they receive the AIDS diagnosis.

Cryptococcal infections are mainly caused by members of the Cryptococcus neoformans species complex (molecular types VNI, VNII, VNB, VNIV and the AD hybrid VNIII). PCR of the mating type loci and MLST typing using the ISHAM-MLST consensus scheme were used to evaluate the genetic relationship of 102 (63 clinical and 39 environmental) C. neoformans isolates from Uberaba, Brazil and to correlate the obtained genotypes with clinical, antifungal susceptibility and virulence factor data. All isolates were mating type alpha. MLST identified 12 known and five new sequence types (ST). Fourteen STs were identified within the VNI isolates, with ST93 (57/102, 56%) and ST77 (19/102, 19%) being the most prevalent. From the nine VNII isolates previously identify by URA5-RFLP only four (ST40) were confirmed by MLST. The remaining five grouped within the VNB clade in the phylogenetic analysis corresponding to the sequence type ST504. Other two environmental isolates also grouped within VNB clade with the new sequence type ST527. The four VNII/ST40 isolates were isolated from CSF. The two VNIV sequence types (ST11 and ST160) were isolated from blood cultures. Two of six patients evaluated with more than one isolates had mixed infections. Amongst the VNI isolates 4 populations were identified, which showed differences in their susceptibility profiles, clinical outcome and virulence factors. These results reinforce that ST93 is the most prevalent ST in HIV-infected patients in the Southeastern region of Brazil. The finding of the VNB molecular type amongst environmental Brazilian isolates highlights that this genotype is not restricted to the African continent.

Cryptococcal meningitis (CM) remains as common life-threatening AIDS-defining illness mainly in resource-limited settings. Previous reports suggested that baseline cytokine profiles can be associated to fungal burden and clinical outcome. This study aimed to evaluate the baseline cytokine profiles in AIDS patients with CM and its relation with the outcome at weeks 2 and 10. Thirty AIDS patients with CM diagnosed by cerebrospinal fluid (CSF) Cryptococcus neoformans positive culture, India ink stain and cryptococcal antigen test were prospectively evaluated. As controls, 56 HIV-infected patients without CM and 48 non-HIV individuals were included. Baseline CSF and sera levels of IL-2, IL-4, IL-8, IL-10, IL-12p40, IL-17A, INF-γ and TNF-α were measured by ELISA. Of 30 CM patients, 24 (80%) were male, median age of 38.1. The baseline CSF high fungal burden and positive blood culture were associated with a positive CSF culture at week 2 (p = 0.043 and 0.029). Most CSF and sera cytokines presented higher levels in CM patients than control subjects (p < 0.05). CSF levels of IL-8, IL-12p40, IL-17A, TNF-α, INF-γ and sera TNF-α were significantly higher among survivors at weeks 2 and 10 (p < 0.05). Patients with increased intracranial pression exhibited CSF IL-10 high levels and poor outcome at week 10 (p = 0.032). Otherwise, baseline CSF log10 IFN-γ and IL-17A were negatively correlated with fungal burden (r = -0.47 and -0.50; p = 0.0175 and 0.0094, respectively). The mortality rate was 33% (10/30) at week 2 and 57% (17/30) at week 10. The severity of CM and the advanced immunodeficiency at admission were related to a poor outcome in these patients. Otherwise, the predominant Th1 cytokines profile among survivors confirms its pivotal role to infection control and would be a prognostic marker in cryptococcal meningitis.

Cryptococcus neoformans and C. gattii are the etiologic agents of cryptococcosis, a life-threatening disease in both immunocompromised and immunocompetent hosts. Antifungal resistance has been evaluated using different methods, breakpoints, and sizes of test populations and it is an emerging as a significant issue worldwide. A total of 176 (95 clinical and 81 environmental) C. neoformans and eight clinical C. gattii isolates were evaluated to determine the minimal inhibitory concentration (MIC) according to the Clinical and Laboratory Standards Institute method. A total of 10.5% of the C. neoformans clinical isolates were resistant to amphotericin B (AMB), and 6.2% of the environmental isolates were resistant to fluconazole (FLZ). Environmental and clinical isolates presented epidemiologic cut-off values (ECVs) of 64 and 16 to FLZ and 1 and 2 to AMB, respectively. All of the C. gattii isolates showed high susceptibility to most drugs evaluated. Clinical isolates had lower susceptibility than environmental isolates to AMB and itraconazole whereas environmental isolates had lower susceptibility than the clinical isolates to FLZ, voriconazole, and ketoconazole. However, no difference was found in the susceptibility of the two species. The MICs and ECVs to antifungals can help to select the best therapeutic option for tracking epidemiological resistance among clinical and environmental isolates of Cryptococcus spp. around the world.