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Cryptococcus neoformans var. grubii is the causative agent of cryptococcal meningitis, a significant source of mortality in immunocompromised individuals, typically human immunodeficiency virus/AIDS patients from developing countries. Despite the worldwide emergence of this ubiquitous infection, little is known about the global molecular epidemiology of this fungal pathogen. Here we sequence the genomes of 188 diverse isolates and characterize the major subdivisions, their relative diversity, and the level of genetic exchange between them. While most isolates of C. neoformans var. grubii belong to one of three major lineages (VNI, VNII, and VNB), some haploid isolates show hybrid ancestry including some that appear to have recently interbred, based on the detection of large blocks of each ancestry across each chromosome. Many isolates display evidence of aneuploidy, which was detected for all chromosomes. In diploid isolates of C. neoformans var. grubii ( serotype AA) and of hybrids with C. neoformans var. neoformans (serotype AD) such aneuploidies have resulted in loss of heterozygosity, where a chromosomal region is represented by the genotype of only one parental isolate. Phylogenetic and population genomic analyses of isolates from Brazil reveal that the previously "African" VNB lineage occurs naturally in the South American environment. This suggests migration of the VNB lineage between Africa and South America prior to its diversification, supported by finding ancestral recombination events between isolates from different lineages and regions. The results provide evidence of substantial population structure, with all lineages showing multi-continental distributions; demonstrating the highly dispersive nature of this pathogen., (Copyright © 2017 Rhodes et al.)

Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was done for five genotypes within C. gattii . In a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was premature and without consensus in the community. Although the authors of the perspective recognized the existence of genetic diversity, they preferred the use of the informal nomenclature " C. neoformans species complex" and " C. gattii species complex." Here we highlight the advantage of recognizing these seven species, as ignoring these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances.

Cryptococcosis has emerged as an important public health problem in Africa, Asia and the Americas due to the increasing numbers of persons at risk of this infection and the adaptation of its aetiological agents to new environments. The proper management requires early recognition of Cryptococcus neoformans/C. gattii species complex infection, familiarity with the use and limitations of diagnostic tests and knowledge of the available treatment options. This review will address these issues with the goal of providing sufficient information to suspect, diagnose and treat patients with cryptococcosis based on Cuban data and review of the literature., (© 2014 Blackwell Verlag GmbH.)

We report two cases of chromoblastomycosis due to Fonsecaea pedrosoi and F. monophora in otherwise healthy Cuban males. Direct microscopic examination of biopsies revealed muriform cells, the hallmark of chromoblastomycosis. The suspected agents were recovered in culture, identified on the basis of morphological criteria and confirmed by sequencing of the internal transcribed spacer regions of rDNA. Final treatment consisted of surgical excision. The patients were successfully cured since there was no relapse after a follow-up of more than a year. In vitro antifungal susceptibility testing of both isolates showed that itraconazole and posaconazole had potent activity. High MICs of amphotericin B (2 μg/ml), fluconazole (>64 μg/ml), anidulafungin (8 μg/ml) and caspofungin (8 μg/ml) were found.

Understanding more about the host's immune response to different Cryptococcus spp. will provide additional insight into the pathogenesis of cryptocococcis. We hypothesized that the ability of C. gattii to cause disease in immunocompetent humans depends on a distinct innate cytokine response of the host to this emerging pathogen. In the current study we assessed the cytokine profile of human peripheral blood mononuclear cells (PBMCs) of healthy individuals, after in vitro stimulation with 40 different well-defined heat-killed isolates of C. gattii, C. neoformans and several hybrid strains. In addition, we investigated the involvement of TLR2, TLR4 and TLR9 in the pro-inflammatory cytokine response to C. gattii. Isolates of C. gattii induced higher concentrations of the pro-inflammatory cytokines IL-1β, TNF-α and IL-6 and the Th17/22 cytokine IL-17 and IL-22 compared to C. neoformans var neoformans and C. neoformans var grubii. In addition, clinical C. gattii isolates induced higher amounts of cytokines than environmental isolates. This difference was not observed in C. neoformans var. grubii isolates. Furthermore, we demonstrated a likely contribution of TLR4 and TLR9, but no role for TLR2, in the host's cytokine response to C. gattii. In conclusion, clinical heat-killed C. gattii isolates induced a more pronounced inflammatory response compared to other Cryptococcus species and non-clinical C. gattii. This is dependent on TLR4 and TLR9 as cellular receptors.

Epidemiological cutoff values (ECVs) for the Cryptococcus neoformans-Cryptococcus gattii species complex versus fluconazole, itraconazole, posaconazole, and voriconazole are not available. We established ECVs for these species and agents based on wild-type (WT) MIC distributions. A total of 2,985 to 5,733 CLSI MICs for C. neoformans (including isolates of molecular type VNI [MICs for 759 to 1,137 isolates] and VNII, VNIII, and VNIV [MICs for 24 to 57 isolates]) and 705 to 975 MICs for C. gattii (including 42 to 260 for VGI, VGII, VGIII, and VGIV isolates) were gathered in 15 to 24 laboratories (Europe, United States, Argentina, Australia, Brazil, Canada, Cuba, India, Mexico, and South Africa) and were aggregated for analysis. Additionally, 220 to 359 MICs measured using CLSI yeast nitrogen base (YNB) medium instead of CLSI RPMI medium for C. neoformans were evaluated. CLSI RPMI medium ECVs for distributions originating from at least three laboratories, which included ≥95% of the modeled WT population, were as follows: fluconazole, 8 μg/ml (VNI, C. gattii nontyped, VGI, VGIIa, and VGIII), 16 μg/ml (C. neoformans nontyped, VNIII, and VGIV), and 32 μg/ml (VGII); itraconazole, 0.25 μg/ml (VNI), 0.5 μg/ml (C. neoformans and C. gattii nontyped and VGI to VGIII), and 1 μg/ml (VGIV); posaconazole, 0.25 μg/ml (C. neoformans nontyped and VNI) and 0.5 μg/ml (C. gattii nontyped and VGI); and voriconazole, 0.12 μg/ml (VNIV), 0.25 μg/ml (C. neoformans and C. gattii nontyped, VNI, VNIII, VGII, and VGIIa,), and 0.5 μg/ml (VGI). The number of laboratories contributing data for other molecular types was too low to ascertain that the differences were due to factors other than assay variation. In the absence of clinical breakpoints, our ECVs may aid in the detection of isolates with acquired resistance mechanisms and should be listed in the revised CLSI M27-A3 and CLSI M27-S3 documents.

Histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, has been reported all over the world and is considered endemic in the American continent, including Cuba. This fungus grows on the soils contaminated with bird and bat excreta, where it produces a great number of microconidia that could cause the infection when they are inhaled. The clinical spectrum varies from asymptomatic infections to serious disseminated diseases involving one or many organ systems and affects mainly AIDS patients, patients with hematological neoplasias, transplant recipients or other immunosuppressed patients. The main risk groups include those individuals whose working activities make them be exposed to aerosols contaminated with H. capsulatum. Lab diagnosis is based on the microscopic observation, isolation and identification of the fungus in fluid or tissue samples of patients, and on specific antigen and antibodies detection. The molecular methods based on polymerase chain reaction have not been sufficiently defined, and they could be an important advance in the early diagnosis of this mycosis. Itraconazole is recommended for treatment of moderate, localized and chronic infection whereas amphotericin B is the drug of choice for disseminated and serious manifestations, particularly in its lipidic formulations. At present, histoplasmosis is considered one of the most important systemic mycoses in the Americas, and it is widely spread over all regions of Cuba.

The in vitro susceptibilities of a worldwide collection of 350 Cryptococcus gattii isolates to seven antifungal drugs, including the new triazole isavuconazole, were tested. With amplified fragment length polymorphism (AFLP) fingerprinting, human, veterinary, and environmental C. gattii isolates were subdivided into seven AFLP genotypes, including the interspecies hybrids AFLP8 and AFLP9. The majority of clinical isolates (n = 215) comprised genotypes AFLP4 (n = 76) and AFLP6 (n = 103). The clinical AFLP6 isolates had significantly higher geometric mean MICs for flucytosine and fluconazole than the clinical AFLP4 isolates. Of the seven antifungal compounds examined in this study, isavuconazole had the lowest MIC(90) (0.125 μg/ml) for all C. gattii isolates, followed by a 1 log(2) dilution step increase (MIC(90), 0.25 μg/ml) for itraconazole, voriconazole, and posaconazole. Amphotericin B had an acceptable MIC(90) of 0.5 μg/ml, but fluconazole and flucytosine had relatively high MIC(90)s of 8 μg/ml.

Introduction: Cryptoccosis--systemic mycosis caused by Cryptococcus species--has considerably raised its incidence in the last years, mainly associated with the human immunodeficiency virus infection. It has also been described in animals, but rare cases., Methods: a case of a female cheetah (Acinonyx jubatus) kept in the Nacional Zoo of Havana was presented. The animal came from South Africa. She began losing weight, and suffering asthenia, anorexia and breathing problems with abundant nasal secretion., Results: mycological testing of these secretions disclosed the presence of serotype B Cryptococcus gattii. Because of the origin and captive condition of the animal, it was believed that the infection had been latent for 16 months at least., Conclusions: up to the present, in Cuba, all clinical Cryptococcus isolates were C. neoformans var. grubii, so it is considered that the infection was caught in the country of origin of the female cheetah. This is the first C. gattii isolate in Cuba from an animal coming from South Africa where this fungus is endemic.

The in vitro activities of eight antifungal drugs against clinical isolates of Fonsecaea pedrosoi (n = 21), Fonsecaea monophora (n = 25), and Fonsecaea nubica (n = 9) were tested. The resulting MIC(90)s for all strains (n = 55) were as follows, in increasing order: posaconazole, 0.063 microg/ml; itraconazole, 0.125 microg/ml; isavuconazole, 0.25 microg/ml; voriconazole, 0.5 microg/ml; amphotericin B, 2 microg/ml; caspofungin, 2 microg/ml; anidulafungin, 2 microg/ml; and fluconazole, 32 microg/ml.

Background: Human cryptococcal infections have been associated with bird droppings as a likely source of infection. Studies toward the local and global epidemiology of Cryptococcus spp. have been hampered by the lack of rapid, discriminatory, and exchangeable molecular typing methods., Methodology/principal Findings: We selected nine microsatellite markers for high-resolution fingerprinting from the genome of C. neoformans var. grubii. This panel of markers was applied to a collection of clinical (n = 122) and environmental (n = 68; from pigeon guano) C. neoformans var. grubii isolates from Cuba. All markers proved to be polymorphic. The average number of alleles per marker was 9 (range 5-51). A total of 104 genotypes could be distinguished. The discriminatory power of this panel of markers was 0.993. Multiple clusters of related genotypes could be discriminated that differed in only one or two microsatellite markers. These clusters were assigned as microsatellite complexes. The majority of environmental isolates (>70%) fell into 1 microsatellite complex containing only few clinical isolates (49 environmental versus 2 clinical). Clinical isolates were segregated over multiple microsatellite complexes., Conclusions/significance: A large genotypic variation exists in C. neoformans var. grubii. The genotypic segregation between clinical and environmental isolates from pigeon guano suggests additional source(s) of human cryptococcal infections. The selected panel of microsatellite markers is an excellent tool to study the epidemiology of C. neoformans var. grubii.

Introduction: histoplasmosis, an infection caused by Histoplasma capsulatum fungus, is considered as one of the main endemic infections in the American continent where there are frequent epidemic outbreaks. Most of the outbreaks have been associated to risky activities in bat-inhabited places. This paper presented two outbreaks of occupational acquired histoplasmosis occurred in La Habana province., Methods: one hundred and sixteen workers, who performed aerosol-generating tasks in caves, were studied. Samples from the cave soils were taken to assess the existence of the causal agent. Clinical and epidemiological data were gathered for the outbreak characterization., Results: the rates of infection for both outbreaks were 60 % and 78 % respectively. The patients aged 16 to 64 years; additionally, the onset of main clinical manifestations (fever, general malaise, cough, headache, loss of weight, and chest pain) ranged from 10 to 20 days. Histoplasmosis was microbiologically and serologically diagnosed whereas its source of infection was confirmed through H. capsulatum isolation in those places where extensive excavation work had been carried out, resulting in abundant aerosols for up to 21d periods. The similarity between the two outbreaks was the performance of aerosol-generating tasks in risky places without using appropriate safety devices., Conclusions: It is necessary to disseminate the existing preventive measures among the health care staff and the risky groups as well as the general population in order to prevent and take control of possible histoplasmosis outbreaks in the future.

Kodamaea (Pichia) ohmeri is a yeast species that has not been reported to be a frequent cause of human infections. The current report describes a case of fungemia caused by K. ohmeri in a 3-year-old female patient hospitalized in the public hospital Maria Alice Fernandes, Natal, RN, Brazil. The patient had previously received antimicrobial therapy due to a peritoneal infection and nosocomial pneumonia, and had a central venous catheter implanted. Kodamaea ohmeri was isolated from blood and the tip of the catheter, 48 h after its implantation. The yeast was identified by standard microbiological methods and sequence analysis of the D1/D2 domains and the ITS 1 + 2 spacer regions of the ribosomal DNA. On CHROMagar Candida medium, the isolate showed a color change from pink to blue. The yeast was susceptible to amphotericin B, and liposomal AmB was used successfully to clear the infection.

Cuban Cryptococcus isolates (n = 165) were tested in vitro against amphotericin B, flucytosine, fluconazole, itraconazole, voriconazole, posaconazole, and isavuconazole, giving MIC90 values of 0.25, 8, 4, 0.25, 0.125, 0.016, and 0.016 microg/ml, respectively. Isavuconazole and posaconazole seem to be potentially active drugs for treating cryptococcal infections.

In vitro antifungal susceptibility testing is really necessary at present in medical mycology laboratories. Minimal inhibitory concentration of 210 Candida yeast strains isolated from HIV/AIDS patients with oral lesions was determined to find out susceptibility to fluconazole and amphotericin B. A CLSI's M27A2 protocol-based dilution micromethod was used. C. albicans was predominant (62.4%)followed by C. glabrata, C. parapsilosis, and C. tropicalis. Regarding amphotericin B, the mode value and MIC50 were 0.125 microg/mL, which indicated the effectiveness of this drug in vitro conditions. Only C. krusei strain showed a minimal inhibitory concentration over 1 microg/mL. 8.1% of strains were resistent to fluconazole whereas 8.1% was dose-depending susceptible. The less susceptible species were C. krusei and C. glabrata. The achieved results laid the foundations for wider studies to be made in the Cuban context and indicated the need of keeping surveillance on the behaviour of clinical yeast isolates to antifungal drugs.

A prospective study to identify clinical and mycological aspects of oral candidiasis including a therapeutic trial for 4 drugs-2 topical (chlotrimazole and nistatine) and 2 systemic (itraconale and ketoconazole) was performed on 97 HIV adult patients from March 2003 to June 2004. Average age was 34.97 years, being males and heterosexual behaviour predominant. The pseudomembranous clinical form of presentation prevailed in 93.8% of cases, with accompanying symptoms like pain, burning sensation and difficult swallowing in addition to extensive lesions. Candida albicans was the most frequently isolated species both in swabs taken at the beginning (92%) and at the end of the treatment schedules applied to patients who did not succeed in mycological cure (89.4%). Treatment schemes had positive results from the clinical viewpoint in 91.8% of cases with improvement or total remission of symptoms and signs, and in 51.6% of mycological curing. There were no statistically significant differences of clinical and mycological responses between topical and systemic treatments. The above-mentioned allowed recommending a more extensive use of local treatment in the studied population because of their benefits for the patients.

The capacity of the 4B3 monoclonal antibody, previously obtained by immunization of BALB/c mice with the capsular polysaccharide of Cryptococcus neoformans was studied to recognize this structure as part of the intact cell of this yeast. With this aim, 4B3 was evaluated by cellular ELISA and indirect immunofluorescence, using as an antigen a cell suspension of the 028 LMIPK C. neoformans strain. Serum from the mouse used in the fusion for obtaining 4B3 monoclonal antibody was used as a positive control, whereas an anti-dengue monoclonal antibody was used as a negative control. Both methods demonstrated that the above mentioned monoclonal antibody is capable of recognizing the native antigen, which will allow its future evaluation for diagnostic and therapeutic purposes.

A comparative study was conducted between the assimilation of D-proline and the growth on canavanine-glycine-bromothymol blue (CGB) medium used for the classification of the varieties of Cryptococcus neoformans. In the 86 studied strains, 100% of coincidence between both methods allowed to affirm that 95.34% corresponded to the neoformans var. and the rest (4.65%) to the gattii var. The results obtained corroborated that all the autoctonous clinical isolations up to the present correspond to the. neoformans var. and made possible to suggest the use of D-proline for the initial evaluation of strains, as an alternative and simple method that presented under these conditions high coincidence with the reference method (growth in CGB).