-
Mycopathologia Oct 2021
Topics: Cryptococcosis; Cryptococcus gattii; Cryptococcus neoformans; Humans
PubMed: 34224075
DOI: 10.1007/s11046-021-00577-7 -
Clinical Microbiology Reviews Oct 2014Understanding of the taxonomy and phylogeny of Cryptococcus gattii has been advanced by modern molecular techniques. C. gattii probably diverged from Cryptococcus... (Review)
Review
Understanding of the taxonomy and phylogeny of Cryptococcus gattii has been advanced by modern molecular techniques. C. gattii probably diverged from Cryptococcus neoformans between 16 million and 160 million years ago, depending on the dating methods applied, and maintains diversity by recombining in nature. South America is the likely source of the virulent C. gattii VGII molecular types that have emerged in North America. C. gattii shares major virulence determinants with C. neoformans, although genomic and transcriptomic studies revealed that despite similar genomes, the VGIIa and VGIIb subtypes employ very different transcriptional circuits and manifest differences in virulence phenotypes. Preliminary evidence suggests that C. gattii VGII causes severe lung disease and death without dissemination, whereas C. neoformans disseminates readily to the central nervous system (CNS) and causes death from meningoencephalitis. Overall, currently available data indicate that the C. gattii VGI, VGII, and VGIII molecular types more commonly affect nonimmunocompromised hosts, in contrast to VGIV. New, rapid, cheap diagnostic tests and imaging modalities are assisting early diagnosis and enabling better outcomes of cerebral cryptococcosis. Complications of CNS infection include increased intracranial pressure, severe neurological sequelae, and development of immune reconstitution syndrome, although the mortality rate is low. C. gattii VGII isolates may exhibit higher fluconazole MICs than other genotypes. Optimal therapeutic regimens are yet to be determined; in most cases, initial therapy with amphotericin B and 5-flucytosine is recommended.
Topics: Animals; Cryptococcosis; Cryptococcus gattii; Humans
PubMed: 25278580
DOI: 10.1128/CMR.00126-13 -
Journal of Fungi (Basel, Switzerland) May 2021The genus comprises more than 80 species, including and , which are pathogenic to humans, mainly affecting the central nervous system. The two species differ in... (Review)
Review
The genus comprises more than 80 species, including and , which are pathogenic to humans, mainly affecting the central nervous system. The two species differ in geographic distribution and environmental niche. has a worldwide distribution and is often isolated from bird droppings. On the contrary, is reported in tropical and subtropical regions and is associated with species. This review aims to describe the distribution of environmental isolates of the species complex and the species complex in Colombia. A systematic investigation was carried out using different databases, excluding studies of clinical isolates reported in the country. The complex of the species of is recovered mainly from trees of the genus spp., while the complex of the species of is recovered mainly from avian excrement, primarily (pigeons) excrement. In addition, greater positivity was found at high levels of relative humidity. Likewise, an association was observed between the presence of the fungus in places with little insolation and cold or temperate temperatures compared to regions with high temperatures.
PubMed: 34073882
DOI: 10.3390/jof7060410 -
American Journal of Ophthalmology Case... Mar 2022To present a case of subretinal abscess associated with pneumonia and meningitis caused by in an immunocompetent host.
PURPOSE
To present a case of subretinal abscess associated with pneumonia and meningitis caused by in an immunocompetent host.
OBSERVATIONS
A 37-year-old man presented with sub-acute painless unilateral vision loss and a white submacular elevation. Systemic evaluation revealed a lung lesion and cerebrospinal fluid evidence of infection.
CONCLUSIONS AND IMPORTANCE
While has been well described as a cause of chorioretinitis in immunocompetent and immunocompromised hosts, this report demonstrates that is a related uncommon pathogen to be considered in similar presentations. Submacular surgical debridement may be challenging and OCT imaging may be helpful to detect full-thickness retinal necrosis.
PubMed: 35112022
DOI: 10.1016/j.ajoc.2022.101283 -
Acta Biochimica Et Biophysica Sinica May 2022is a kind of basidiomycetous yeast, which grows in human and animal hosts. . has four distinct genomes, VGI/AFLP4, VGII/AFLP6, VGIII/AFLP5, and VGIV/AFLP7. The... (Review)
Review
is a kind of basidiomycetous yeast, which grows in human and animal hosts. . has four distinct genomes, VGI/AFLP4, VGII/AFLP6, VGIII/AFLP5, and VGIV/AFLP7. The virulence of . is closely associated with genotype and related stress-signaling pathways, but the pathogenic mechanism of . has not been fully identified. With the development of genomics and transcriptomics, the relationship among genes, regulatory mechanisms, virulence, and treatment is gradually being recognized. In this review, to better understand how . causes disease and to characterize hypervirulent . strains, we summarize the current understanding of . genotypes, phenotypes, virulence, and the regulatory mechanisms.
Topics: Humans; Animals; Cryptococcus gattii; Virulence; DNA, Fungal; Genotype
PubMed: 35593469
DOI: 10.3724/abbs.2022029 -
Journal of Fungi (Basel, Switzerland) Dec 2022species are a major cause of life-threatening infections in immunocompromised and immunocompetent hosts. While most disease is caused by , , a genotypically and... (Review)
Review
species are a major cause of life-threatening infections in immunocompromised and immunocompetent hosts. While most disease is caused by , , a genotypically and phenotypically distinct species, is responsible for 11-33% of global cases of cryptococcosis. Despite best treatment, infections are associated with early mortality rates of 10-25%. The World Health Organization's recently released Fungal Priority Pathogen List classified as a medium-priority pathogen due to the lack of effective therapies and robust clinical and epidemiological data. This narrative review summarizes the latest research on the taxonomy, epidemiology, pathogenesis, laboratory testing, and management of infections.
PubMed: 36675862
DOI: 10.3390/jof9010041 -
Journal of Fungi (Basel, Switzerland) Mar 2018The fungal pathogens and can cause life-threatening infections in immune compromised and immune competent hosts. These pathogens enter the host via inhalation, and... (Review)
Review
The fungal pathogens and can cause life-threatening infections in immune compromised and immune competent hosts. These pathogens enter the host via inhalation, and respiratory tract innate immune cells such as dendritic cells (DCs) are one of the first host cells they encounter. The interactions between and innate immune cells play a critical role in the progression of disease in the host. This review will focus specifically on the interactions between and dendritic cells (DCs), including recognition/processing by DCs, effects of immune mediators on DC recruitment and activity, and the potential for DC vaccination against cryptococcosis.
PubMed: 29543719
DOI: 10.3390/jof4010036 -
Frontiers in Cellular and Infection... 2022is an invasive fungus that seriously endangers human life and health, with a complex and well-established immune-escaping mechanism that interferes with the function of... (Review)
Review
is an invasive fungus that seriously endangers human life and health, with a complex and well-established immune-escaping mechanism that interferes with the function of the host immune system. can attenuate the host's correct recognition of the fungal antigen and escape the immune response mediated by host phagocytes, innate lymphoid cells, T lymphocytes, B lymphocytes with antibodies, and peripheral cytokines. In addition, the capsule, melanin, dormancy, Titan cells, biofilm, and other related structures of are also involved in the process of escaping the host's immunity, as well as enhancing the ability of to infect the host.
Topics: Humans; Cryptococcosis; Cryptococcus neoformans; Immunity, Innate; Lymphocytes; Cytokines; Cryptococcus gattii
PubMed: 36310879
DOI: 10.3389/fcimb.2022.1041036 -
Cold Spring Harbor Perspectives in... Jul 2014Cryptococcus neoformans and Cryptococcus gattii are the two etiologic agents of cryptococcosis. They belong to the phylum Basidiomycota and can be readily distinguished... (Review)
Review
Cryptococcus neoformans and Cryptococcus gattii are the two etiologic agents of cryptococcosis. They belong to the phylum Basidiomycota and can be readily distinguished from other pathogenic yeasts such as Candida by the presence of a polysaccharide capsule, formation of melanin, and urease activity, which all function as virulence determinants. Infection proceeds via inhalation and subsequent dissemination to the central nervous system to cause meningoencephalitis. The most common risk for cryptococcosis caused by C. neoformans is AIDS, whereas infections caused by C. gattii are more often reported in immunocompetent patients with undefined risk than in the immunocompromised. There have been many chapters, reviews, and books written on C. neoformans. The topics we focus on in this article include species description, pathogenesis, life cycle, capsule, and stress response, which serve to highlight the specializations in virulence that have occurred in this unique encapsulated melanin-forming yeast that causes global deaths estimated at more than 600,000 annually.
Topics: Cryptococcosis; Cryptococcus gattii; Cryptococcus neoformans; Drug Resistance, Multiple, Fungal; Enzymes; Fungal Capsules; Genotype; Host-Pathogen Interactions; Humans; Life Cycle Stages; Melanins; Phenotype; Signal Transduction; Stress, Physiological; Terminology as Topic; Virulence Factors
PubMed: 24985132
DOI: 10.1101/cshperspect.a019760 -
Fungal Genetics and Biology : FG & B May 2015Cryptococcosis is a significant invasive fungal infection with noteworthy morbidity and mortality, primarily caused by Cryptococcus neoformans and Cryptococcus gattii.... (Review)
Review
Cryptococcosis is a significant invasive fungal infection with noteworthy morbidity and mortality, primarily caused by Cryptococcus neoformans and Cryptococcus gattii. In China, C. neoformans var. grubii (especially molecular type VNI) is the most common variety in the environment and responsible for the majority of cryptococcal infections. C. gattii infections are quite rare in China and the primary molecular type is VGI, which is closely related to C. gattii isolates in Australia. Interestingly, the majority of cryptococcosis in China were reported in the HIV-uninfected patients (especially immunocompetent hosts). This unique phenomenon may be attributed to multiple polymorphisms in the genes encoding mannose-binding lectin (MBL) and Fc-gamma receptor 2B (FCGR2B) in the Han population, the major ethnic group in China. Compared to immunocompromised patients, immunocompetent patients with cryptococcal meningitis often presented with more intense inflammatory responses and more severe neurological complications, but less fungal burdens and disseminated infection. The overall prognosis, which is independently associated with amphotericin B-based initial therapy, is similar between immunocompetent and immunocompromised patients. In addition, intrathecal administration of amphotericin B has been proved to be an effective adjunctive treatment for cryptococcosis in China.
Topics: Amphotericin B; Antifungal Agents; China; Cryptococcosis; Cryptococcus neoformans; Genotype; HIV Infections; Humans; Injections, Spinal; Molecular Epidemiology; Mycological Typing Techniques; Survival Analysis; Treatment Outcome
PubMed: 25445309
DOI: 10.1016/j.fgb.2014.10.017