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1.
Microbiol Spectr ; 12(7): e0390223, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38842310

RESUMO

Cryptococcus neoformans and Cryptococcus gattii are both known urease producers and have the potential to cause hyperammonemia. We hypothesized that the risk of hyperammonemia is increased by renal failure, burden of cryptococcal infection, and fungal strain characteristics. We performed a retrospective review of plasma ammonia levels in patients with cryptococcal infections. Risk factors for hyperammonemia were statistically compared between patients with and without hyperammonemia (>53 µmol/L). Cryptococcal cells from three patients included in the study were recovered from our biorepository. Strain characteristics including urease activity, ammonia production, growth curves, microscopy, melanin production, and M13 molecular typing were analyzed and compared with a wild-type (WT) C. neoformans strain. We included 29 patients, of whom 37.9% had hyperammonemia, 59% had disseminated cryptococcal infection (DCI), and 41% had isolated central nervous system infection. Thirty-eight percent of patients had renal failure and 28% had liver disease. Renal failure was associated with 4.4 times (95% confidence interval [CI] 1.5, 13.0) higher risk of hyperammonemia. This risk was higher in DCIs (RR 6.2, 95% CI 1.0, 40.2) versus isolated cryptococcal meningitis (RR 2.5, 95% CI, 0.40, 16.0). Liver disease and cryptococcal titers were not associated with hyperammonemia. C. neoformans from one patient with extreme hyperammonemia demonstrated a 4- to 5-fold increase in extracellular urease activity, slow growth, enlarged cell size phenotypes, and diminished virulence factors. Hyperammonemia was strongly associated with renal failure in individuals with DCI, surpassing associations with liver failure or cryptococcal titers. However, profound hyperammonemia in one patient was attributable to high levels of urease secretion unique to that cryptococcal strain. Prospective studies are crucial to exploring the significance of this association.IMPORTANCECryptococcus produces and secretes the urease enzyme to facilitate its colonization of the host. Urease breaks down urea into ammonia, overwhelming the liver's detoxification process and leading to hyperammonemia in some hosts. This underrecognized complication exacerbates organ dysfunction alongside the infection. Our study investigated this intricate relationship, uncovering a strong association between the development of hyperammonemia and renal failure in patients with cryptococcal infections, particularly those with disseminated infections. We also explore mechanisms underlying increased urease activity, specifically in strains associated with extreme hyperammonemia. Our discoveries provide a foundation for advancing research into cryptococcal metabolism and identifying therapeutic targets to enhance patient outcomes.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Hiperamonemia , Urease , Humanos , Criptococose/microbiologia , Hiperamonemia/microbiologia , Hiperamonemia/etiologia , Feminino , Estudos Retrospectivos , Masculino , Pessoa de Meia-Idade , Urease/metabolismo , Adulto , Idoso , Amônia/metabolismo , Fatores de Risco , Insuficiência Renal/complicações , Insuficiência Renal/microbiologia , Idoso de 80 Anos ou mais
2.
Med Mycol ; 62(6)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935902

RESUMO

Cryptococcosis causes a high burden of disease worldwide. This systematic review summarizes the literature on Cryptococcus neoformans and C. gattii infections to inform the World Health Organization's first Fungal Priority Pathogen List. PubMed and Web of Science were used to identify studies reporting on annual incidence, mortality, morbidity, antifungal resistance, preventability, and distribution/emergence in the past 10 years. Mortality rates due to C. neoformans were 41%-61%. Complications included acute renal impairment, raised intracranial pressure needing shunts, and blindness. There was moderate evidence of reduced susceptibility (MIC range 16-32 mg/l) of C. neoformans to fluconazole, itraconazole, ketoconazole, voriconazole, and amphotericin B. Cryptococcus gattii infections comprised 11%-33% of all cases of invasive cryptococcosis globally. The mortality rates were 10%-23% for central nervous system (CNS) and pulmonary infections, and ∼43% for bloodstream infections. Complications described included neurological sequelae (17%-27% in C. gattii infections) and immune reconstitution inflammatory syndrome. MICs were generally low for amphotericin B (MICs: 0.25-0.5 mg/l), 5-flucytosine (MIC range: 0.5-2 mg/l), itraconazole, posaconazole, and voriconazole (MIC range: 0.06-0.5 mg/l). There is a need for increased surveillance of disease phenotype and outcome, long-term disability, and drug susceptibility to inform robust estimates of disease burden.


Assuntos
Antifúngicos , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Farmacorresistência Fúngica , Organização Mundial da Saúde , Humanos , Criptococose/epidemiologia , Criptococose/microbiologia , Criptococose/mortalidade , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/isolamento & purificação , Testes de Sensibilidade Microbiana
3.
Indian J Med Microbiol ; 49: 100609, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38735642

RESUMO

We discuss a rare instance of cryptococcoma caused by Cryptococcus gattii in a 55-year-old woman initially treated for suspected COVID bronchopneumonia. The diagnosis posed a challenge due to vague symptoms and unclear imaging findings suggesting malignancy. Postoperative samples confirmed the presence of Cryptococcus gattii through culture of brain tissue and blood. Appropriate therapy was initiated, but despite treatment, it led to a fatal outcome. The case emphasizes the crucial role of microbiologist in early diagnosis of fungal infections of Central Nervous System. Additionally, the delayed diagnosis in immunocompetent individuals highlights the critical need for early recognition and intervention to mitigate potentially fatal outcomes.


Assuntos
Criptococose , Cryptococcus gattii , Glioblastoma , Humanos , Feminino , Pessoa de Meia-Idade , Cryptococcus gattii/isolamento & purificação , Criptococose/diagnóstico , Criptococose/microbiologia , Glioblastoma/diagnóstico , Diagnóstico Diferencial , Evolução Fatal , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/microbiologia , Neoplasias Encefálicas/diagnóstico , Antifúngicos/uso terapêutico , COVID-19/diagnóstico
4.
Methods Mol Biol ; 2775: 29-46, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758309

RESUMO

Cryptococcus neoformans and Cryptococcus gattii are the predominant etiological agents of cryptococcosis, a particularly problematic disease in immunocompromised individuals. The increased clinical use of immunosuppressive drugs, the inherent ability of Cryptococcus species to suppress and evade host immune responses, and the emergence of drug-resistant yeast support the need for model systems that facilitate the design of novel immunotherapies and antifungals to combat disease progression. The mouse model of cryptococcosis is a widely used system to study Cryptococcus pathogenesis and the efficacy of antifungal drugs in vivo. In this chapter, we describe three commonly used strategies to establish cryptococcosis in mice: intranasal, intratracheal, and intravenous inoculations. Also, we discuss the methodology for delivering drugs to mice via intraperitoneal injection.


Assuntos
Criptococose , Cryptococcus neoformans , Modelos Animais de Doenças , Animais , Criptococose/microbiologia , Criptococose/tratamento farmacológico , Criptococose/imunologia , Camundongos , Cryptococcus neoformans/patogenicidade , Cryptococcus gattii/patogenicidade , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico
5.
Braz J Microbiol ; 55(2): 1369-1380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38619732

RESUMO

Cryptococcosis is one of the major life-threatening opportunistic/systemic fungal diseases of worldwide occurrence, which can be asymptomatic or establish pneumonia and meningoencephalitis mainly in immunosuppressed patients, caused by the Cryptococcus neoformans and C. gattii species complexes. Acquisition is by inhaling fungal propagules from avian droppings, tree hollows and decaying wood, and the association of the molecular types with geographic origin, virulence and antifungal resistance have epidemiological importance. Since data on cryptococcosis in Alagoas are limited, we sought to determine the molecular types of etiological agents collected from clinical and environmental sources. We evaluated 21 isolates previously collected from cerebrospinal fluid and from environment sources (pigeon droppings and tree hollows) in Maceió-Alagoas (Brazil). Restriction fragment length polymorphism of URA5 gene was performed to characterize among the eight standard molecular types (VNI-VNIV and VGI-VGIV). Among isolates, 66.67% (14) were assigned to C. neoformans VNI - 12 of them (12/14) recovered from liquor and 2 from a tree hollow (2/14). One isolate from pigeon droppings (4.76%) corresponded to C. neoformans VNIV, while five strains from tree hollows and one from pigeon droppings (6, 28.57%) to C. gattii VGII. VNI-type was present in clinical and environmental samples and most C. neoformans infections were observed in HIV-positive patients, while types VNIV and VGII were prevalent in environmental sources in Alagoas. This is the first molecular characterization of Cryptococcus spp. in Alagoas, our study provides additional information on the ecoepidemiology of Cryptococcus spp. in Brazil, contributing to a closer view of the endemic species.


Assuntos
Columbidae , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Microbiologia Ambiental , Cryptococcus neoformans/genética , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/classificação , Brasil/epidemiologia , Criptococose/microbiologia , Criptococose/epidemiologia , Cryptococcus gattii/genética , Cryptococcus gattii/isolamento & purificação , Cryptococcus gattii/classificação , Humanos , Animais , Columbidae/microbiologia , Técnicas de Tipagem Micológica , Polimorfismo de Fragmento de Restrição , Fezes/microbiologia , Genótipo
6.
Front Cell Infect Microbiol ; 14: 1321886, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558853

RESUMO

Cryptococcosis is a life-threatening invasive fungal infection with significantly increasing mortality worldwide, which is mainly caused by Cryptococcus neoformans and Cryptococcus gattii. These two species complexes have different epidemiological and clinical characteristics, indicating the importance of accurate differential diagnosis. However, the clinically used culture method and cryptococcal capsular antigen detection couldn't achieve the above goals. Herein, we established a novel duplex flap probe-based isothermal assay to identify the Cryptococcus neoformans and Cryptococcus gattii within 1 hour. This assay combined the highly sensitive nucleic acid isothermal amplification and highly specific fluorescence probe method, which could effectively distinguish the sequence differences of the two species complexes using two different fluorescence flap probes in a single reaction system. This novel method showed excellent detection performance with sensitivity (10 copies/µL each) and specificity (100%) compared to traditional culture and sequencing methods. Furthermore, we applied this method to spiked clinical samples, 30 cerebrospinal fluids and 30 bronchoalveolar lavage fluids, which kept good detection performance. This novel rapid duplex flap probe-based isothermal assay is a promising and robust tool for applications in differential diagnosis of the Cryptococcus neoformans and Cryptococcus gattii in clinical settings, especially when clinical suspicion for cryptococcal disease is high and epidemiological studies.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Cryptococcus neoformans/genética , Cryptococcus gattii/genética , Criptococose/diagnóstico , Criptococose/microbiologia , Antígenos de Fungos , Líquido da Lavagem Broncoalveolar
7.
Curr Protoc ; 4(3): e1001, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38456766

RESUMO

Cryptococcus is recognized as one of the emerging fungal pathogens that have major impact on diverse populations worldwide. Because of the high mortality rate and limited antifungal therapy options, there is an urgent need to understand the impact of dynamic processes between fungal pathogens and hosts that influence cryptococcal pathogenesis and disease outcomes. With known common limitations in human studies, experimental murine cryptococcosis models that can recapitulate human disease provide a valuable tool for studying fungal virulence and the host interaction, leading to development of better treatment strategies. Infection with Cryptococcus in mice via intranasal inhalation is mostly used because it is noninvasive and considered to be the most common mode of infection, strongly correlating with cryptococcal disease in humans. The protocols described in this article provide the procedures of establishing a murine model of Cryptococcus infection by intranasal inhalation and assessing the host immune response and disease progression during Cryptococcus infection. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Murine model of pulmonary cryptococcal infection via intranasal inhalation Basic Protocol 2: Assessment of the pulmonary immune response during Cryptococcus infection Support Protocol: Evaluation of pulmonary gene expression by real-time PCR Basic Protocol 3: Enumeration of survival rate and organ fungal burden.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Animais , Camundongos , Cryptococcus neoformans/genética , Modelos Animais de Doenças , Criptococose/microbiologia , Criptococose/patologia , Pulmão/microbiologia , Pulmão/patologia
8.
Front Immunol ; 15: 1356651, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469300

RESUMO

Cryptococcus neoformans and C. gattii, the etiologic agents of cryptococcosis, cause over 100,000 deaths worldwide every year, yet no cryptococcal vaccine has progressed to clinical trials. In preclinical studies, mice vaccinated with an attenuated strain of C. neoformans deleted of three cryptococcal chitin deacetylases (Cn-cda1Δ2Δ3Δ) were protected against a lethal challenge with C. neoformans strain KN99. While Cn-cda1Δ2Δ3Δ extended the survival of mice infected with C. gattii strain R265 compared to unvaccinated groups, we were unable to demonstrate fungal clearance as robust as that seen following KN99 challenge. In stark contrast to vaccinated mice challenged with KN99, we also found that R265-challenged mice failed to induce the production of protection-associated cytokines and chemokines in the lungs. To investigate deficiencies in the vaccine response to R265 infection, we developed a KN99-R265 coinfection model. In unvaccinated mice, the strains behaved in a manner which mirrored single infections, wherein only KN99 disseminated to the brain and spleen. We expanded the coinfection model to Cn-cda1Δ2Δ3Δ-vaccinated mice. Fungal burden, cytokine production, and immune cell infiltration in the lungs of vaccinated, coinfected mice were indicative of immune evasion by C. gattii R265 as the presence of R265 neither compromised the immunophenotype established in response to KN99 nor inhibited clearance of KN99. Collectively, these data indicate that R265 does not dampen a protective vaccine response, but rather suggest that R265 remains largely undetected by the immune system.


Assuntos
Coinfecção , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Vacinas , Camundongos , Animais , Evasão da Resposta Imune
9.
Biosens Bioelectron ; 250: 116096, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38316089

RESUMO

Fast and accurate detection of Cryptococcus and precise differentiation of its subtypes is of great significance in protecting people from cryptococcal disease and preventing its spread in populations. However, traditional Cryptococcus identification and detection techniques still face significant challenges in achieving high analysis speed as well as high sensitivity. In this work, we report an electric microfluidic biochip. Compared to conventional methods that take several hours or even a day, this chip can detect Cryptococcus within 20 min, and achieve its maximum detection limit within 1 h, with the ability to differentiate between the Cryptococcus neoformans (NEO) and rare Cryptococcus gattii (GAT) efficiently, which accounts for nearly 100%. This device integrated two functional zones of an electroporation lysis (EL) zone for rapid cell lysis (<30 s) and an electrochemical detection (ED) zone for sensitive analysis of the released nucleic acids. The EL zone adopted a design of microelectrode arrays, which obtains a large electric field intensity at the constriction of the microchannel, addressing the safety concerns associated with high-voltage lysis. The device enables a limit of detection (LOD) of 60 pg/mL for NEO and 100 pg/mL for GAT through the modification of nanocomposites and specific probes. In terms of the detection time and sensitivity, the integrated microfluidic biochip demonstrates broad potential in Cryptococcus diagnosis and disease prevention.


Assuntos
Técnicas Biossensoriais , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Criptococose/diagnóstico
10.
Microbiol Spectr ; 12(4): e0290323, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38411053

RESUMO

Cryptococcus neoformans and Cryptococcus gattii cause cryptococcosis, a systemic mycosis that infects a wide range of species. Recent molecular biological investigations have allowed for the genotyping of these species, providing more detailed information on their pathogenicity and infection routes. Koalas (Phascolarctos cinereus) are frequently colonized by Cryptococcus spp., but molecular epidemiological studies have yet to be conducted in Japan. Here, we conducted multi-locus sequence typing (MLST) analysis on Cryptococcus spp. colonization isolates obtained from all koalas kept in seven parks across Japan. Out of 46 koalas examined, 10 (22%) were positive for C. gattii and 3 (6.5%) were positive for C. neoformans. All C. gattii isolates belonged to molecular type VGI and were either sequence type (ST) 51 or a novel ST, and all C. neoformans isolates belonged to molecular type VNI and ST23. Despite the frequent movement of koalas between parks, the STs were relatively park-specific, suggesting that the floor of the rearing barns is a source of infection and may act as a reservoir. MLST analysis confirmed that C. gattii was transported, established, and spread by koalas in areas where C. gattii was not originally present. MLST analysis is considered useful in assessing the pathogenicity and tracing the transmission routes of Cryptococcus spp. carried by koalas.IMPORTANCEThis is the first study to conduct a multi-locus sequence typing analysis on Cryptococcus spp. carried by captive koalas in Japan. Cryptococcosis remains a globally high-fatality fungal infection in humans, and captive koalas are known to carry a high percentage of Cryptococcus spp. Through this research, the molecular types and transmission routes of Cryptococcus spp. carried by koalas have been elucidated, revealing the potential role of enclosure flooring as a reservoir. It has been confirmed that Cryptococcus gattii, which is not endemic in Japan, has become established through koalas and is spreading to new individuals in Japan. This study is believed to provide valuable insights into koala conservation and contribute to the One Health approach for Cryptococcosis, a zoonotic infection.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Phascolarctidae , Animais , Humanos , Phascolarctidae/microbiologia , Tipagem de Sequências Multilocus , Japão/epidemiologia , Cryptococcus neoformans/genética , Criptococose/epidemiologia , Criptococose/veterinária , Criptococose/microbiologia , Cryptococcus gattii/genética , Genótipo
11.
Int J Antimicrob Agents ; 63(3): 107090, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242250

RESUMO

This study examined the geographic distribution of minimum inhibitory concentrations (MICs) of antifungals against Cryptococcus isolates. Data were collected on the MICs of specific antifungals (amphotericin B, 5-flucytosine, fluconazole, voriconazole, posaconazole, and isavuconazole) against various Cryptococcus species for the period 2010 to 2020 from the Antimicrobial Testing Leadership and Surveillance database. Cryptococcus isolates were collected from samples of blood and cerebrospinal fluid (CSF) from patients hospitalized in different regions worldwide. We applied the epidemiological cutoff values (ECVs) of antifungals against various Cryptococcus species to distinguish wild-type (WT) from non-WT Cryptococcus isolates. A total of 395 isolates of Cryptococcus species cultured from blood (n = 201) or CSF (n = 194) were analyzed. C. grubii (n = 270), C. neoformans (n = 111), and C. gattii (n = 11) were the three predominant species causing bloodstream infections (BSI) or meningitis/meningoencephalitis (MME). The proportion of MICs above the ECV (1 mg/L) for amphotericin B among C. neoformans isolates was significantly lower than that among C. gattii isolates (MICs >0.5 mg/L; P < 0.001), as evaluated using the chi-square test. For most isolates of the three predominant Cryptococcus species, the MICs of new triazoles were ≤0.25 mg/L. The MICs of fluconazole and amphotericin B in the BSI/MME-causing Cryptococcus isolates collected from patients hospitalized in the Asia-Western Pacific region and Europe were significantly lower (i.e., the distributions were more leftward) than those in North America and Latin America. Ongoing monitoring of MIC data for important antifungals against cryptococcosis is crucial.


Assuntos
Anti-Infecciosos , Cryptococcus gattii , Cryptococcus neoformans , Endrin/análogos & derivados , Humanos , Antifúngicos/farmacologia , Anfotericina B , Fluconazol/farmacologia , Liderança
12.
Pathog Dis ; 822024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38204138

RESUMO

Infections caused by Cryptococcus gattii mainly affect immunocompetent individuals and the treatment presents important limitations. This study aimed to validate the efficacy of selective serotonin reuptake inhibitors (SSRI), fluoxetine hydrochloride (FLH), and paroxetine hydrochloride (PAH) in vitro against C. gattii. The antifungal activity of SSRI using the microdilution method revealed a minimal inhibitory concentration (MIC) of 31.25 µg/ml. The combination of FLH or PAH with amphotericin B (AmB) was analyzed using the checkerboard assay and the synergistic effect of SSRI in combination with AmB was able to reduce the SSRI or AmB MIC values 4-8-fold. When examining the effect of SSRI on the induced capsules, we observed that FLH and PAH significantly decreased the size of C. gattii capsules. In addition, the effects of FLH and PAH were evaluated in biofilm biomass and viability. The SSRI were able to reduce biofilm biomass and biofilm viability. In conclusion, our results indicate the use of FLH and PAH exhibited in vitro anticryptococcal activity, representing a possible future alternative for the cryptococcosis treatment.


Assuntos
Cryptococcus gattii , Cryptococcus neoformans , Humanos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Antifúngicos/farmacologia , Anfotericina B/farmacologia , Testes de Sensibilidade Microbiana , Fluoxetina/farmacologia , Paroxetina/farmacologia , Biofilmes
13.
Clin Microbiol Infect ; 30(5): 660-665, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38295989

RESUMO

OBJECTIVES: To explore the seroprevalence of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies in non-HIV cryptococcal meningitis (CM) and assess its predictive value for survival. METHODS: This is a retrospective study of 12 years of non-HIV CM. We detected serum anti-GM-CSF autoantibodies, and evaluated the clinical features and outcomes, together with the exploration of prognostic factors for 2-week and 1-year survival. RESULTS: A total of 584 non-HIV CM cases were included. 301 of 584 patients (51.5%) were phenotypically healthy. 264 Cryptococcus isolates were obtained from cerebrospinal fluid (CSF) culture, of which 251 were identified as C. neoformans species complex and 13 as C. gattii species complex. Thirty-seven of 455 patients (8.1%) tested positive for serum anti-GM-CSF autoantibodies. Patients with anti-GM-CSF autoantibodies were more susceptible to C. gattii species complex infection (66.7% vs. 6.3%; p < 0.001) and more likely to develop pulmonary mass lesions with a diameter >3 centimetres (42.9% vs. 6.5%; p 0.001). Of 584 patients 16 (2.7%) died within 2 weeks, 77 of 563 patients (13.7%) died at 1 year, and 93 of 486 patients (19.1%) lived with disabilities at 1 year. Univariant Cox regression analysis found that anti-GM-CSF autoantibodies were associated with lower 1-year survival (HR, 2.66; 95% CI, 1.34-5.27; p 0.005). Multivariable Cox proportional hazards modelling revealed that CSF cryptococcal antigen titres ≥1:1280 were associated with both, reduced 2-week and 1-year survival rates (HR, 5.44; 95% CI, 1.23-24.10; p 0.026 and HR, 5.09; 95% CI, 1.95-13.26; p 0.001). DISCUSSION: Presence of serum anti-GM-CSF autoantibodies is predictive of poor outcomes, regardless of host immune status and the causative Cryptococcus species complex.


Assuntos
Autoanticorpos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Meningite Criptocócica , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoanticorpos/sangue , Autoanticorpos/líquido cefalorraquidiano , Cryptococcus gattii/imunologia , Cryptococcus neoformans/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Meningite Criptocócica/mortalidade , Meningite Criptocócica/imunologia , Meningite Criptocócica/diagnóstico , Prognóstico , Estudos Retrospectivos , Estudos Soroepidemiológicos
14.
Acta Biochim Biophys Sin (Shanghai) ; 56(2): 291-303, 2024 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-37885429

RESUMO

Cryptococcus gattii (Cg) is a facultative intracellular pathogen that can replicate and disseminate in mammalian macrophages, causing life-threatening cryptococcosis in both immunocompetent and immunocompromised individuals. Cryptococcus-macrophage interactions are crucial for cryptococcosis prognosis. However, the relationship between Cg pathogenicity and phagocytosis by macrophages has not yet been investigated in depth. In this study, a series of in vitro and in vivo experiments were conducted to investigate the interaction between macrophages and Cg. Flow cytometry was used to detect the phagocytic phenotypes of the Cg strains within macrophages. Scanning electron microscopy, transmission electron microscopy, and immunofluorescence were used to observe phagocytosis and proliferation, respectively. Survival and lung fungal burden tests were also performed. Our results show that Cg cells display different phagocytosis phenotypes, which are independent of the molecular type. Within macrophages, the high phagocytosis phenotype (HP) strains obtain higher intracellular proliferation than the low phagocytosis phenotype (LP) strains. At the early stage of infection in vivo, HP-inducing permissive granulomas within the lungs seldom limit the dissemination of cryptococci. In addition, HP strains could inhibit the formation of M1-type macrophages, proliferate intracellularly and disseminate extracellularly, and cause hypoxia induced by mucus and acidic polysaccharide accumulation in pulmonary alveoli much earlier than LP strains in vivo. Our work reveals that Cg displays diverse interactions with macrophages, which may enhance our understanding of the pathogenicity of this life-threatening pathogen.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Animais , Cryptococcus gattii/genética , Virulência , Macrófagos/microbiologia , Fagocitose , Criptococose/microbiologia , Fenótipo , Mamíferos
15.
J Proteomics ; 290: 105022, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-37838096

RESUMO

Cryptococcus gattii is a primary pathogenic fungus that causes pneumonia. This species is also responsible for an outbreak in Vancouver, Canada, and spreading to the mainland and United States. The use of medical devices is often complicated by infections with biofilm-forming microbes with increased resistance to antimicrobial agents and host defense mechanisms. This study investigated the comparative proteome of C. gattii R265 (VGIIa) grown under planktonic and biofilm conditions. A brief comparison with C. neoformans H99 biofilm and the use of different culture medium and surface were also evaluated. Using Multidimensional Protein Identification Technology (MudPIT), 1819 proteins were identified for both conditions, where 150 (8.2%) were considered differentially regulated (up- or down-regulated and unique in biofilm cells). Overall, the proteomic approach suggests that C. gattii R265 biofilm cells are maintained by the induction of electron transport chain for reoxidation, and by alternative energy metabolites, such as succinate and acetate. SIGNIFICANCE: Since C. gattii is considered a primary pathogen and is one of the most virulent and less susceptible to antifungals, understanding how biofilms are maintained is fundamental to search for new targets to control this important mode of growth that is difficult to eradicate.


Assuntos
Cryptococcus gattii , Cryptococcus neoformans , Cryptococcus gattii/metabolismo , Transporte de Elétrons , Proteômica , Elétrons , Biofilmes
16.
Microbiol Spectr ; 11(6): e0244323, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37905820

RESUMO

IMPORTANCE: Our study indicates that the molecular typing of Cryptococcus gattii is unrelated to virulence. The integration of animal experiments and clinical prognosis demonstrated that pathogenicity did not exhibit a direct correlation with in vitro virulence phenotypes or molecular genotypes, emphasizing the intricate nature of virulence. In conclusion, our research holds the potential to provide valuable insights into understanding the microbiological attributes of C. gattii in China.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Animais , Cryptococcus gattii/genética , Cryptococcus neoformans/genética , Virulência , Tipagem Molecular , Genótipo , China , Criptococose/microbiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-37702231

RESUMO

Cryptococcus neoformans and C. gattii pneumonitis could persist asymptomatically for indefinite periods, resolve, or progress to symptomatic dissemination, mainly in immunocompromised individuals (e.g., treated with corticosteroids). The symptoms of COVID-19 may range from a self-limiting illness with general symptoms, such as fever, to more severe complications, such as pneumonitis. The glucocorticoids emerged as potential for treatment of COVID-19, mainly those patients who required ventilator therapy. However, although treatment with glucocorticoids has shown benefits in patients with COVID-19, they can be dangerous due to increased risk of coinfections and superinfections caused by opportunistic pathogens such as Cryptococcus ssp. Some patients with severe COVID-19 pneumonia treated with glucocorticoids developed cryptococcal infection and died. Therefore, immunomodulatory therapy could increase the susceptibility to acute infection or reactivation of Cryptococcus ssp in COVID-19 patients, and this could be complicated once pulmonary cryptococcosis has symptoms similar to COVID-19 becomes difficult to distinguish between the two disease states and treatment.


Assuntos
COVID-19 , Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Glucocorticoides/uso terapêutico , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Cryptococcus gattii/fisiologia
18.
Sci Rep ; 13(1): 15755, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735454

RESUMO

The Cryptococcus genus comprises more than 100 species, of which C. neoformans and C. gattii are the leading cause of cryptococcosis. The distribution of C. gattii and C. neoformans species complexes has been extensively studied and widely reported globally. Other species such as Naganishia albida, Papiliotrema laurentii, and Papiliotrema flavescens have been reported as pathogenic yeasts. Since there are no reports of environmental isolation in the Boyacá region (Colombia), this study aimed to isolate and characterize Cryptococcus and Cryptococcus-like yeasts from pigeon feces, Eucalyptus, and olive trees distributed in the municipalities of Tunja and Ricaute Alto. The environmental data was recovered, and the isolations obtained were identified by microscopy, biochemical test, MALDI-TOF MS, URA5-RFLP, and sequencing of the ITS and LSU loci. For the 93 pigeon dropping samples collected in Tunja, 23 yielded to C. neoformans, 3 to N. globosa, 2 N. albida and 1 to P. laurentii. Of the 1188 samples collected from olive trees, 17 (1.43%) positive samples were identified as C. gattii species complex (4), C. neoformans species complex (2), P. laurentii (3), N. albida (2), N. globosa (5) and P. flavescens (1). Likewise, specimens of C. neoformans presented molecular type VNI and molecular type VNII; for C. gattii the molecular types found were VGIII and one VGIV by URA5-RFLP but VGIII by MALDI-TOF and sequencing of the ITS and LSU. Therefore, it can be concluded that the species of Cryptococcus, Naganishia and Papiliotrema genera, are present in the environment of Boyacá, and show a predilection for climate conditions that are typical of this region.


Assuntos
Criptococose , Cryptococcus gattii , Cryptococcus neoformans , Olea , Animais , Colômbia , Clima , Columbidae
19.
Aust Vet J ; 101(10): 377-382, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37537848

RESUMO

BACKGROUND: Cryptococcus is one of the most common systemic mycosis worldwide, infecting young adults of the large to giant breed dogs. Infection is commonly acquired from the environment via the sinonasal cavity as the main portal of entry. It either remains there, or spreads to the central nervous system (CNS) and the eye (optic nerve and retina) by penetration of the cribriform plate, or haematogenously to other viscera. Lung involvement is uncommon in cats and dogs in contrast to human and equine patients. Whilst there is a wide genetic diversity amongst Cryptococcus neoformans and Cryptococcus gattii isolates along the West Coast and Northern parts of Australia, the molecular diversity of C. gatti is considered very low on the East Coast of Australia, with a huge preponderance of VGI cases. We report on a young small breed brachycephalic dog that presented with extreme gastrointestinal and respiratory signs, but no CNS involvement. It is the first reported case of C. gattii VGII genotype in a companion animal from Queensland. CASE REPORT: A 9-month old female entire French Bulldog presented initially for diarrhoea. Clinical progression was accompanied by the development of respiratory signs, so the patient was referred to a 24 h care facility. Following hospitalisation, the patient became hypoxemic requiring mechanical ventilation. A bronchoalveolar lavage performed antemortem confirmed abundant Cryptococcal spp. Further culturing and genotyping identified the species as Cryptococcus gattii VGII. Post-mortem findings indicated gross gastrointestinal and mesenteric involvement, with possible dissemination to the local mesenteric lymph node and lungs. CONCLUSION: This case describes a rare example of a Cryptococcus spp suspected of disseminating from the gastrointestinal tract to the lungs, without involvement of the CNS. The observation of this finding in a small brachycephalic breed is unusual, and the finding of genotype VGII on the East Coast of Queensland is extremely unusual as there is no prior travel history of the dog or owners. The presence of a miliary lung pattern with primary gastrointestinal disease in a small breed dog warrants adding cryptococcosis to the differential diagnosis.


Assuntos
Doenças do Gato , Criptococose , Cryptococcus gattii , Doenças do Cão , Doenças dos Cavalos , Cães , Humanos , Animais , Feminino , Cavalos , Gatos , Cryptococcus gattii/genética , Queensland/epidemiologia , Melhoramento Vegetal , Criptococose/diagnóstico , Criptococose/veterinária , Criptococose/complicações , Austrália , Genótipo , Doenças do Cão/diagnóstico
20.
J Med Case Rep ; 17(1): 332, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542340

RESUMO

BACKGROUND: Cryptococcal meningitis (CM) is an inflammatory mycosis of the central nervous system caused by meninge infection or brain parenchyma with Cryptococcus species. It is associated with high morbidity and mortality, and patients with acquired immune deficiency syndrome are particularly susceptible. There have been increasing reports of CM in HIV-negative patients in China over the last few years. CASE PRESENTATION: A 31-year-old healthy Chinese male presented with fever and gradually developed headache, projectile vomiting, and other manifestations that were later confirmed as Cryptococcus gattii meningoencephalitis. However, multiple disease changes occurred during the course of treatment, and the regimen was accordingly modified after the diagnosis of post-infectious inflammatory response syndrome (PIIRS). The patient eventually recovered. CONCLUSION: There has been a growing trend in the incidence of C. gattii meningoencephalitis in HIV-negative patients. It shows rapid onset and severe prognosis. This case report can provide a reference to treat PIIRS following CM in HIV-negative patients.


Assuntos
Cryptococcus gattii , Inflamação , Meningite Criptocócica , Meningoencefalite , Humanos , Masculino , Adulto , Meningoencefalite/complicações , Meningoencefalite/diagnóstico por imagem , Meningoencefalite/tratamento farmacológico , Infecções por HIV , Inflamação/etiologia , Imageamento por Ressonância Magnética , Meningite Criptocócica/complicações , Meningite Criptocócica/diagnóstico por imagem , Meningite Criptocócica/tratamento farmacológico
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