Cryptococcosis by Cryptococcus neoformans/Cryptococcus gattii Species Complexes in non-HIV-Infected Patients in Southeastern Brazil

Abstract INTRODUCTION: The clinical manifestations of cryptococcosis are usually associated with the infecting agents Cryptococcus neoformans (CN) and C. gattii (CG) species complexes and the host. In this study, non-HIV-infected patients, at a university hospital in southeastern Brazil, had epidemiological and clinical data associated with cryptococcal disease and isolated Cryptococcus species: CN - 24 patients and CG - 12 patients. METHODS: The comparison was comprised of demographic data, predisposing factors, clinical and laboratory manifestations, and outcomes of cryptococcosis patients treated between 2000 and 2016. Immunocompetent and immunosuppressed patients were also compared, irrespective of the infecting species. Cryptococcus spp. were genotyped by PCR-RFLP analysis of the URA5 gene. RESULTS: Infections by the CN species complex (100% VNI genotype) were associated with drug immunosuppression and fungemia, and patients infected with the CG species complex (83% VG II and 17% VGI genotypes) had more evident environmental exposure and higher humoral response. CN and CG affected patients with or without comorbidities. CONCLUSIONS: Diabetes mellitus, other chronic non-infectious diseases, and alcoholism were likely predisposing factors for infection by both CN and CG species. Immunocompetent patients, independent of the infecting Cryptococcus species complexes, showed a higher occurrence of meningitis and a trend toward less fungal dissemination and longer survival than immunosuppressed hosts.

Frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes in Argentina / Frecuencia y distribución geográfica de genotipos y tipos sexuales de los complejos de especies Cryptococcus neoformans y Cryptococcus gattii en Argentina

Abstract The aim of this work was to know the frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes isolated from human infections in Argentina during the period from April 2009 to April 2011. A multicenter study was conducted, in which 372 isolates were obtained from 61 laboratories throughout the country. Of those, 98.8% of the isolates belonged to the C. neoformans species complex and 1.1% to the C. gattii species complex. Genotype VNI (MATa) was the most frequently isolated (n = 326, 87.6%), followed by VNII (MATa) (n = 22, 5.9%), the recently described VNII-VNIV (aADa) hybrid (n = 14, 3.8%), VNIV (MATa) (n=4, 1.1%), VNIII (aADa) hybrid (n = 1, 0.3%), and VNIII (aADa) hybrid (n = 1, 0.3%). The Argentine Central region showed the greatest number of cases and genotype diversity. Interestingly, a relative high frequency was observed in genotype VNII (MATa) in the Cuyo, Northeast and Northwest regions and, also in VNII-VNIV (aADa) hybrids in the Northwest region. C. gattii species complex was isolated at a low rate; 3 VGI (MATa) and 1 VGII (MATa) isolates were obtained from the Northwest and Central regions. In conclusion, this study shows that genotype frequencies seem to vary among regions in Argentina and reveals a relatively high frequency of rare hybrids in the Northwest region. Further regional clinical and environmental studies may help to elucidate if those varia-tions in frequencies are associated with the existence of regional ecological niches or any other regional factors.

Resumen El objetivo de! trabajo fue conocer la frecuencia y la distribución geográfica de genotipos y tipos sexuales de aislados pertenecientes a los complejos de especies Cryptococcus neoformansy Cryptococcus gattii obtenidos de infecciones humanas en Argentina. Entre abril de 2009 y abril de 2011 se realizó un estudio multicéntrico del que se obtuvieron 372 aislados de 61 laboratorios de diferentes zonas del país. El 98,8% de los aislados pertenecieron al complejo C. neoformansy el 1,1% al complejo C. gattii. El genotipo VNI (MATa) fue el más frecuente (n = 326; 87,6%), le siguieron VNII (MATa) (n = 22; 5,9%), el híbrido VNII-VNIV (aADa) (n = 14; 3,8%), VNIV (MATa) (n =4; 1,1%) y los híbridos VNIII (aADa) (n = 1; 0,3%) y VNIII (aADa) (n = 1; 0,3%). La región Centro mostró el mayor número de casos y la mayor diversidad de genotipos. Cabe destacar que el genotipo VNII (MATa) tuvo una frecuencia relativamente alta en las regiones de Cuyo, Noreste y Noroeste. En esta última región, también fue alta la frecuencia del híbrido VNII-VNIV (aADa). La frecuencia de aislamiento de miembros del complejo C. gattii fue baja: se obtuvieron 3 aislados VGI (MATa) y 1 VGII (MATa) de las regiones Centro y Noroeste. En conclusión, este estudio muestra que las frecuencias de genotipos varían entre las distintas regiones de Argentina y señala la presencia de híbridos poco comunes en una frecuencia relativamente alta dentro de la región Noroeste. Contar con mayor número de estudios clínicos y ambientales regionales podría ayudar a elucidar si tales variaciones están asociadas a la existencia de nichos ecológicos particulares o a algún otro factor regional.

Clinical and microbiological characteristics of cryptococcosis at an university hospital in China from 2013 to 2017

ABSTRACT Background: This study aims to explore the epidemiology, clinical profile and strain characteristics of cryptococcosis from 2013 to 2017 in a major teaching hospital in China. Methods: Trends in antifungal drug susceptibility of 217 consecutive non-repetitive cryptococcal isolates collected from patients of an university hospital in China were analyzed between 2013 and 2017. Of those, 98 isolates were conserved for identification by internal transcribed spacer (ITS) sequencing and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system. Multilocus sequence typing (MLST) was used to designate molecular types. Clinical characteristics of the 98 patients with cryptococcosis during the period of 2013-2017 were retrospectively evaluated. Results: There was a trend for gradual increase in the MIC range of fluconazole was from 2013 to 2017. The conserved 98 clinical cryptococcal isolates included 97 C. neoformans and one C. gattii, and 90 (91.8%) isolates belonged to ST5 genotype VNI. Out of the 98 patients with cryptococcosis, 28 (28.6%) were HIV-infected and 32 (32.7%) had no underlying diseases. HIV-infected patients had higher mortality than HIV-uninfected patients (28.6% vs 14.3%, p = 0.147). Conclusions: Most of the patients with cryptococcosis were not HIV-infected in this study, while patients with HIV had a higher mortality. Reduced susceptibility to fluconazole was observed among C. neoformans isolates, most of them belonged to ST5 genotype VNI having an impact on the effective dose of fluconazole.

Cryptococcal meningitis epidemiology: 17 years of experience in a State of the Brazilian Pantanal

Abstract INTRODUCTION: This study aimed to describe cryptococcal meningitis (CM) cases and the associated demographic, clinical, and microbiological data obtained from cities in the State of Mato Grosso do Sul in the Midwestern region of Brazil. METHODS: The data from 129 patients with laboratory-confirmed CM admitted from 1997 to 2014 were retrospectively reviewed. The molecular types of Cryptococcus neoformans and Cryptococcus gattii isolated from cerebrospinal fluid were analyzed to determine their geographic distribution. RESULTS: The patients had a mean age of 37 years and consisted mostly of men (76.7%). Most of the Cryptococcus isolates were obtained from patients infected with human immunodeficiency virus (HIV) and included 105 (87.5%) and 5 (55.6%) isolates of C. neoformans and C. gattii complexes, respectively. A restriction fragment length polymorphism (RFLP) analysis of URA5 revealed that most of the isolates were C. neoformans molecular type VNI (89.1%), whereas the molecular types VGII (7%) and VNII (3.9%) were observed less frequently. Notably, 65% of the cases with a time from symptom onset to laboratory diagnosis of more than 60 days resulted in fatalities, and sequelae were observed among the patients who survived. CONCLUSIONS: The present study documents the occurrence of neurocryptococcosis, which is mainly caused by C. neoformans VNI, in Mato Grosso do Sul, Brazil, with probable autochthonous cases in the Brazilian Pantanal, the world's largest tropical wetland, and a biome where cryptococcosis has not yet been explored.

Advances in Cryptococcus genomics: insights into the evolution of pathogenesis

Cryptococcus species are the causative agents of cryptococcal meningitis, a significant source of mortality in immunocompromised individuals. Initial work on the molecular epidemiology of this fungal pathogen utilized genotyping approaches to describe the genetic diversity and biogeography of two species, Cryptococcus neoformans and Cryptococcus gattii. Whole genome sequencing of representatives of both species resulted in reference assemblies enabling a wide array of downstream studies and genomic resources. With the increasing availability of whole genome sequencing, both species have now had hundreds of individual isolates sequenced, providing fine-scale insight into the evolution and diversification of Cryptococcus and allowing for the first genome-wide association studies to identify genetic variants associated with human virulence. Sequencing has also begun to examine the microevolution of isolates during prolonged infection and to identify variants specific to outbreak lineages, highlighting the potential role of hyper-mutation in evolving within short time scales. We can anticipate that further advances in sequencing technology and sequencing microbial genomes at scale, including metagenomics approaches, will continue to refine our view of how the evolution of Cryptococcus drives its success as a pathogen.

Fatal Cryptococcus gattii genotype VGI infection in an HIV-positive patient in Barranquilla, Colombia

ABSTRACT Cryptococcosis is a major invasive fungal disease related worldwide with the AIDS population. New reports of HIV/AIDS cases to the national public health surveillance system (SIVIGILA) in Colombia have shown that there is a growing community at risk of contracting cryptococcosis throughout the country who do not have access to ART. Even though the most prevalent species Cryptococcus neoformans is mainly associated with the HIV population, we report a fatal case of cryptococcosis in an AIDS patient in Barranquilla, associated with Cryptococcus gattii VGI, isolated from blood culture.

Distribution and association between environmental and clinical isolates of Cryptococcus neoformans in Bogotá-Colombia, 2012-2015

The propagules of the fungal species Cryptococcus neoformans and C. gattii, whose varieties are distributed world wide, are the primary cause of cryptococcosis, a life threatening disease. The study of environmental and clinical isolates of Cryptococcosis is an important contribution to the epidemiology and ecology of the fungus. The aim of this work was to determine the presence of C. neoformans and C. gattii in the environment in Bogotá, Colombia’s capital city and to establish the relation between clinical and environmental isolates in the period 2012-2015. From a total of 4.116 environmental samples collected between October 2012 - March 2014, 35 were positive for C. neoformans var. grubii. From 55 cryptococcosis cases reported in Bogotá during 2012-2015, 49 isolates were recovered. From those, 94% were identified as C. neoformans var. grubii molecular type VNI; 4% as VNII and 1,2% as C. neoformans var neoformans VNIV. The 84 detected clinical and environmental isolates studied had a similarity between 49-100% according with molecular typing. The correlation between environmental and clinical samples confirms the hypothesis that patients acquire the disease from environmental exposure to the fungal propagules.

Validation and clinical application of a molecular method for the identification of Cryptococcus neoformans/Cryptococcus gattii complex DNA in human clinical specimens

ABSTRACT The diagnosis of cryptococcosis is usually performed based on cultures of tissue or body fluids and isolation of the fungus, but this method may require several days. Direct microscopic examination, although rapid, is relatively insensitive. Biochemical and immunodiagnostic rapid tests are also used. However, all of these methods have limitations that may hinder final diagnosis. The increasing incidence of fungal infections has focused attention on tools for rapid and accurate diagnosis using molecular biological techniques. Currently, PCR-based methods, particularly nested, multiplex and real-time PCR, provide both high sensitivity and specificity. In the present study, we evaluated a nested PCR targeting the gene encoding the ITS-1 and ITS-2 regions of rDNA in samples from a cohort of patients diagnosed with cryptococcosis. The results showed that in our hands, this Cryptococcus nested PCR assay has 100% specificity and 100% sensitivity and was able to detect until 2 femtograms of Cryptococcus DNA.

Molecular diagnosis of cryptococcal meningitis in cerebrospinal fluid: comparison of primer sets for Cryptococcus neoformans and Cryptococcus gattii species complex

Aim: This study evaluated the use of polymerase chain reaction for cryptococcal meningitis diagnosis in clinical samples. Materials and methods: The sensitivity and specificity of the methodology were evaluated using eight Cryptococcus neoformans/C. gattii species complex reference strains and 165 cere- brospinal fluid samples from patients with neurological diseases divided into two groups: 96 patients with cryptococcal meningitis and AIDS; and 69 patients with other neurological opportunistic diseases (CRL/AIDS). Two primer sets were tested (CN4-CN5 and the multiplex CNa70S-CNa70A/CNb49S-CNb-49A that amplify a specific product for C. neoformans and another for C. gattii). Results: CN4-CN5 primer set was positive in all Cryptococcus standard strains and in 94.8% in DNA samples from cryptococcal meningitis and AIDS group. With the multiplex, no 448-bp product of C. gattii was observed in the clinical samples of either group. The 695 bp products of C. neoformans were observed only in 64.6% of the cryptococcal meningitis and AIDS group. This primer set was negative for two standard strains. The specificity based on the negative samples from the CTL/AIDS group was 98.5% in both primer sets. Conclusions: These data suggest that the CN4/CN5 primer set was highly sensitive for the identification of C. neoformans/C. gattii species complex in cerebrospinal fluid samples from patients with clinical suspicion of cryptococcal meningitis. .

Identification of genes expressed by Cryptococcus gattii during iron deprivation

Cryptococcus neoformans and C. gattii are pathogenic yeasts that cause life-threatening diseases in humans and animals. Iron is an essential nutrient for virtually every organism as it functions as a cofactor in numerous essential enzymatic reactions. In the literature, the competition for iron between microbes and mammalian hosts during infection is well documented. In this study, we used representational difference analysis (RDA) in order to gain a better understanding of how C. gattii responds to iron starvation. A total of 15 and 29 genes were identified as having altered expression levels due to iron depletion after 3 h and 12 h, respectively. Of these, eight genes were identified in both libraries. The transcripts were related to many biological processes, such as cell cycle, ergosterol metabolism, cell wall organization, transportation, translation, cell respiration and the stress response. These data suggest a remodeling of C. gattii metabolism during conditions of iron deprivation.

Genotipificación de aislamientos clínicos del complejo Cryptococcus neoformans/Cryptococcus gattii obtenidos en el Hospital ½Dr. Julio C. Perrando», de la ciudad de Resistencia (Chaco, Argentina) / [Genotyping of Cryptococcus neoformans/Cryptococcus gattii complex clinical isolates from Hospital \"Dr. Julio C. Perrando\", Resistencia city (Chaco, Argentina)].

Cryptococcosis is a fungal infection caused by yeast species of Cryptococcus genus, particularly Cryptococcus neoformans/Cryptococcus gattii species complex. The knowledge of the cryptococcosis casuistic in northeastern Argentina is scarce and there is no information about the molecular types circulating in this area. The aim of this study was to genotyping C. neoformans/C. gattii complex clinical isolates obtained at Hospital "Dr. Julio C. Perrando", Resistencia city (Chaco, Argentina), in order to determine species, variety and molecular type. During two years and one month 26 clinical isolates were studied. Using conventional and molecular methods one isolate was identified as C. gattii VGI type, and 25 isolates as C. neoformans var. grubii; 23 of these belonged to VNI type and two belonged to VNII type. This data is a contribution to the knowledge of cryptococcosis epidemiology in Argentina and the first report about C. neoformans/ C. gattii complex molecular types from clinical isolates in northeastern Argentina.

Antifungal susceptibilities of Cryptococcus species complex isolates from AIDS and non-AIDS patients in Southeast China

Cryptococcus spp. are common causes of mycoses in immunocompromised patients. To determine the drug susceptibilities of clinical Cryptococcus spp. isolates, the characteristics of 61 clinical Cryptococcus spp. complex isolates and their antifungal susceptibilities were investigated, including 52 C. neoformans and 9 C. gattii isolates collected at Shanghai between 1993 and 2009. Antifungal susceptibility of clinical isolates to amphotericin B, fluconazole, itraconazole, and flucytosine were determined by the microdilution method M27-A2 and the ATB FUNGUS 3 kit. The 90% minimum inhibitory concentration (MIC90) and susceptibility ranges were as follows: 1 (0.0625-1) µg/mL for amphotericin B, 4 (0.125-16) µg/ mL for fluconazole, 0.25 (0.0313-4) µg/mL for itraconazole, and 4 (0.125-8) µg/mL for flucytosine. Fluconazole, itraconazole, and flucytosine have excellent in vitro activity against all tested clinical Cryptococcus spp., and we also found a high rate of tolerance to amphotericin B (MICs ranging from 0.55-1 µg/mL). Furthermore, C. neoformans isolates from acquired immune deficiency syndrome (AIDS) patients were less susceptible to fluconazole and flucytosine than those from non-AIDS patients. These data suggest that use of amphotericin B may lead to tolerance or resistance of the pathogen over time. There were also no significant associations between species, genotypes, and in vitro susceptibilities of these clinical isolates.

Genotypes of Cryptococcus neoformans and Cryptococcus gattii as agents of endemic cryptococcosis in Teresina, Piauí (northeastern Brazil)

Throughout Brazil, Cryptococcus neoformans is the cause of cryptococcosis, whereas Cryptococcus gattii is endemic to the northern and northeastern states. In this study, the molecular types of 63 cryptococcal isolates recovered from the cerebrospinal fluid of meningitis patients diagnosed between 2008-2010 in Teresina, Piauí, Brazil, were analysed. Out of the 63 patients, 37 (58.7 percent) were human immunodeficiency virus (HIV)-positive and 26 (41.3 percent) were HIV-negative. URA5-restriction fragment length polymorphism analysis identified 37/63 (58.7 percent) isolates as the C. neoformans VNI genotype, predominantly in HIV-positive patients (32/37, 86.5 percent), and 24/63 (38.1 percent) as the C. gattii VGII genotype, mostly in HIV-negative patients (21/26, 80.8 percent). The occurrence of C. gattii VGII in six apparently healthy children and in seven adolescents/young adults in this region reaffirms the endemic occurrence of C. gattii VGII-induced primary cryptococcosis and early cryptococcal infection. Lethality occurred in 18/37 (48.6 percent) of the HIV-positive subjects and in 13/26 (50 percent) of the HIV-negative patients. Our results provide new information on the molecular epidemiology of C. neoformans and C. gattii in Brazilian endemic areas.

Cryptococcus gattii molecular type VGII as agent of meningitis in a healthy child in Rio de Janeiro, Brazil: report of an autochthonous case / Cryptococcus gattii tipo molecular VGII como agente causador de meningoencefalite em criança saudável no Rio de Janeiro, Brasil: relato de um caso autóctone

Cryptococcus gattii causes meningoencephalitis in immunocompetent hosts, occurring endemically in some tropical and subtropical regions. Recently, this fungus was involved in an outbreak in Vancouver Island and British Columbia (Canada). In this temperate region, the VGII type is predominant. The paper describes an autochthonous case of meningoencephalitis by C. gattii VGII in a previously health child in Rio de Janeiro, considered nonendemic region of Brazil. The fungus was identified by biochemical tests and the molecular type was determined by URA5-RFLP. The present report highlights the need for clinical vigilance for primary cryptococcal meningitis in nonendemic areas.

Cryptococcus gattii é causa de meningoencefalite em hospedeiros imunocompetentes, ocorrendo endemicamente em regiões tropicais e subtropicais. Recentemente foi causador de surtos na Ilha de Vancouver e na Columbia Britânica (Canadá). Nesta região de clima temperado, o tipo VGII é predominante. Relatamos um caso de meningoencefalite pelo C.gattii tipo VGII acometendo criança previamente saudável autóctone do Rio de Janeiro, região não endêmica do Brasil. O agente foi identificado por testes bioquímicos e o tipo molecular determinado através de URA5-RFLP. O presente relato enfatiza a necessidade de vigilância clínica para a meningite criptocóccica primária em áreas não endêmicas.

Primeira descrição da caracterização fenotípica e susceptibilidade in vitro a drogas de leveduras do gênero Cryptococcus spp isoladas de pacientes HIV positivos e negativos, Estado de Mato Grosso / First description of phenotypic profile and in vitro drug susceptibility of Cryptococcus spp yeast isolated from HIV-positive and HIV-negative patients in State of Mato Grosso

Foram avaliados 37 isolados de 10 pacientes HIV negativos e 26 positivos, em Mato Grosso. Exame direto, cultura e quimiotipagem de espécies foram realizados. Cetoconazol, itraconazol, voriconazol, fluconazol e anfotericina B foram avaliados. Foram identificadas 37 leveduras do gênero Cryptococcus spp sendo 26 de pacientes HIV- positivos (25 Cryptococcus neoformans e um Cryptococcus gattii) e 10 de HIV- negativos (cinco Cryptococcus neoformans e cinco Cryptococcus gattii). Considerando isolados clínicos (Cryptococcus neoformans) de HIV positivos observou-se resistência (8 por cento e 8,7 por cento) e susceptibilidade dose-dependência (20 por cento e 17,4 por cento) para fluconazol e itraconazol respectivamente. Para isolados de Cryptococcus neoformans oriundos de pacientes HIV negativos, observou-se susceptibilidade dose-dependência (40 por cento) ao fluconazol. Os isolados de Cryptococcus gattii provenientes de pacientes HIV- negativos mostraram-se susceptíveis a todos os antifúngicos, exceto um isolado de Cryptococcus gattii que foi susceptível dose-dependente ao fluconazol (20 por cento). O isolado proveniente do paciente HIV- positivo demonstrou resistência ao fluconazol (CIM > 256µg/mL) e itraconazol (CIM=3µg/mL).

Thirty-seven isolates from 10 HIV-negative and 26 HIV-positive patients in Mato Grosso were evaluated. Direct examination, culturing and chemotyping of species were performed. Ketoconazole, itraconazole, voriconazole, fluconazole and amphotericin B were evaluated. Thirty-seven yeasts of Cryptococcus spp were identified, of which 26 were from HIV-positive patients (25 Cryptococcus neoformans and one Cryptococcus gattii) and 10 from HIV-negative patients (five Cryptococcus neoformans and five Cryptococcus gattii). The Cryptococcus neoformans clinical isolates from HIV-positive patients showed resistance (8 percent and 8.7 percent) and dose-dependent susceptibility (20 percent and 17.4 percent) to fluconazole and itraconazole, respectively. Among the Cryptococcus neoformans isolates from HIV-negative patients, there was dose-dependent susceptibility (40 percent) to fluconazole. Cryptococcus gattii isolates from HIV-negative patients were shown to be susceptible to all antifungal agents, except for one isolate of Cryptococcus gattii that showed dose-dependent susceptibility to fluconazole (20 percent). The Cryptococcus gattii isolate from an HIV-positive patient showed resistance to fluconazole (MIC > 256 »g/ml) and itraconazole (MIC = 3 »g/ml).

First isolation of Cryptococcus gattii molecular type VGII and Cryptococcus neoformans molecular type VNI from environmental sources in the city of Belém, Pará, Brazil

Cryptococcus neoformans and Cryptococcus gattii are important agents of meningoencephalitis in humans in the city of Belém. This clinical data suggests that the region may be a highly endemic area for the pathogenic Cryptococcus species within the state of Pará (PA), Northern Brazil. Preliminary analysis of 11 environmental samples from the city of Belém showed two positive locations, including a hollow of a kassod tree (Senna siamea) colonized simultaneously by C. gattii molecular type VGII and C. neoformans molecular type VNI, and a birdcage in a commercial aviary positive for C. neoformans, molecular type VNI. This is the first evidence of an environmental occurrence of molecular types VNI and VGII in PA.