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1.
J Clin Immunol ; 44(7): 163, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008214

RESUMEN

BACKGROUND: Cryptococcosis is a life-threatening disease caused by Cryptococcus neoformans or C. gattii. Neutralizing autoantibodies (auto-Abs) against granulocyte-macrophage colony-stimulating factor (GM-CSF) in otherwise healthy adults with cryptococcal meningitis have been described since 2013. We searched for neutralizing auto-Abs in sera collected from Colombian patients with non-HIV-associated cryptococcosis in a retrospective national cohort from 1997 to 2016. METHODS: We reviewed clinical and laboratory records and assessed the presence of neutralizing auto-Abs against GM-CSF in 30 HIV negative adults with cryptococcosis (13 caused by C. gattii and 17 caused by C. neoformans). RESULTS: We detected neutralizing auto-Abs against GM-CSF in the sera of 10 out of 13 (77%) patients infected with C. gattii and one out of 17 (6%) patients infected with C. neoformans. CONCLUSIONS: We report eleven Colombian patients diagnosed with cryptococcosis who had auto-Abs that neutralize GM-CSF. Among these patients, ten were infected with C. gattii and only one with C. neoformans.


Asunto(s)
Anticuerpos Neutralizantes , Autoanticuerpos , Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Humanos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Masculino , Colombia , Femenino , Adulto , Cryptococcus gattii/inmunología , Persona de Mediana Edad , Cryptococcus neoformans/inmunología , Criptococosis/inmunología , Criptococosis/diagnóstico , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Estudios Retrospectivos , Seronegatividad para VIH/inmunología , Adulto Joven , Anciano
2.
BMC Infect Dis ; 24(1): 645, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937714

RESUMEN

BACKGROUND: Tuberculosis (TB), one of the leading causes of death worldwide, has a higher incidence among indigenous people. Albeit uncommon, autoimmune hemolytic anemia (AIHA) has been deemed a risk condition to develop mycobacterial infection, as a result of the immunosuppressive treatments. TB, in turn, can be a predisposing factor for secondary infections. CASE PRESENTATION: Here we present a case of a 28-year-old indigenous woman from Colombia, previously diagnosed with AIHA and pulmonary TB. Despite various treatments, therapies and medical interventions, the patient died after severe medullary aplasia of multiple causes, including secondary myelotoxicity by immunosuppressive therapy and secondary disseminated infections, underlining infection by Staphylococcus aureus, Klebsiella pneumoniae and Candida glabrata, which were identified as drug-resistant microorganisms. Together, this led to significant clinical complications. Invasive aspergillosis was diagnosed at autopsy. CONCLUSIONS: This report presents a rarely finding of AIHA followed by TB, and highlights the great challenges of dealing with co-infections, particularly by drug resistant pathogens. It also aims to spur governments and public health authorities to focus attention in the prevention, screening and management of TB, especially among vulnerable communities, such as indigenous people.


Asunto(s)
Anemia Hemolítica Autoinmune , Coinfección , Humanos , Femenino , Adulto , Coinfección/microbiología , Resultado Fatal , Anemia Hemolítica Autoinmune/complicaciones , Colombia , Klebsiella pneumoniae/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación , Candida glabrata/aislamiento & purificación , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/microbiología , Infecciones Estafilocócicas/microbiología , Pueblos Indígenas , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología
3.
Mycopathologia ; 188(1-2): 51-61, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36609823

RESUMEN

The aim of this study was to determine the genotypic diversity of 22 Cryptococcus gattii species complex clinical isolates from Argentina and to place these genotypes within the diversity of clinical, veterinary and environmental isolates from Latin America. Mating type and antifungal susceptibility of the isolates were also determined. By URA5-RFLP, nine isolates were identified as molecular type VGI, 10 as VGII, one as VGIII and two as VGIV. Multilocus sequence typing (MSLT), following the International Society for Human and Animal Mycology (ISHAM) consensus MLST scheme, was used to determine the genotypic diversity. Our results suggest that, in Argentina, VGI isolates have low genetic diversity, while VGII isolates have high genetic diversity. Both isolates identified as VGIV by URA5-RFLP were genotyped by MLST as belonging to the currently named VGVI clade. From all isolates, eight sequence types (STs) were unique for Argentina, while five STs have been reported already in other countries, being of high interest the genotypes ST20 and ST7 since they belong to the subtypes VGIIa and VGIIb, respectively, which are associated with hypervirulent strains responsible for outbreaks in North America. To note, geographical analysis showed that some genotypes may be associated with some regions in Argentina. Most isolates were MATα, but we are reporting one isolate MATa for the first time in the country. Antifungal susceptibility tests showed that itraconazole, voriconazole and posaconazole had high activity against all isolates, while amphotericin B, fluconazole and 5-fluorocytosine were the least active drugs against all studied isolates.


Asunto(s)
Criptococosis , Cryptococcus gattii , Animales , Humanos , Antifúngicos/farmacología , Tipificación de Secuencias Multilocus , Argentina , Criptococosis/microbiología , Genotipo
4.
Int J Mol Sci ; 24(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37372935

RESUMEN

Antimicrobial peptides (AMPs) represent a promising class of therapeutic biomolecules that show antimicrobial activity against a broad range of microorganisms, including life-threatening pathogens. In contrast to classic AMPs with membrane-disrupting activities, new peptides with a specific anti-biofilm effect are gaining in importance since biofilms could be the most important way of life, especially for pathogens, as the interaction with host tissues is crucial for the full development of their virulence in the event of infection. Therefore, in a previous study, two synthetic dimeric derivatives (parallel Dimer 1 and antiparallel Dimer 2) of the AMP Cm-p5 showed specific inhibition of the formation of Candida auris biofilms. Here we show that these derivatives are also dose-dependently effective against de novo biofilms that are formed by the widespread pathogenic yeasts C. albicans and C. parapsilosis. Moreover, the activity of the peptides was demonstrated even against two fluconazole-resistant strains of C. auris.


Asunto(s)
Candida albicans , Fluconazol , Fluconazol/farmacología , Candida parapsilosis , Antifúngicos/farmacología , Candida , Biopelículas , Péptidos/farmacología , Pruebas de Sensibilidad Microbiana
5.
Med Mycol ; 60(9)2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36066645

RESUMEN

Cryptococcus neoformans (Cn) and Cryptococcus gattii (Cg) cause cryptococcosis, a life-threatening systemic mycosis of global distribution affecting mainly immunocompromised adults. Although a humoral response occurs during cryptococcosis, the role of antibody production against this mycosis is not fully understood. We aimed to determine total and specific antibodies against cryptococcal protein antigens in sera from people with and without a diagnosis of cryptococcosis from Colombia. Using ELISA, total and specific levels of immunoglobulin (Ig)G, IgA and IgM were determined in sera from children and adults with (n = 109) and without (n = 119) cryptococcosis. Specific antibodies were those binding Cn- and Cg-protein antigens. In general, the mean of the total IgG production was higher in cryptococcosis patients than in controls (13 942.32 vs. 6459.91 µg/ml), while levels of IgA (488.13 vs. 1564.53 µg/ml) and IgM (775.69 vs. 1014.72 µg/ml) were higher in controls than in cryptococcosis patients (P ≤ .05). In patients with cryptococcosis, total IgG, IgA and IgM levels were higher in HIV + compared with HIV- (P ≤ .05). Specific antibodies tended to be higher in cryptococcosis patients than in controls and in adults than in children, with a positive correlation between antibody reactivity and age. All immunoglobulins were more reactive against Cn-proteins than Cg-proteins. Overall, a positive weak correlation between total and specific antibodies was found, although not always statistically significant. In patients with cryptococcosis from Colombia, the levels of immunoglobulins, total and specific, differ with respect to people without cryptococcosis. Variations in antibody production among adults and children with cryptococcosis and between Cn- and Cg-protein antigens were as well established. Our findings encourage further studies to determine the role of humoral immunity for host defense against cryptococcosis.


Differential IgG, IgA, and IgM production and their reactivity with cryptococcal proteins, both among children and adults with and without a diagnosis of cryptococcosis from Colombia, lead to reappraise the study of the potential role of antibody production as host defense against this fungal infection.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Infecciones por VIH , Animales , Antígenos Fúngicos , Colombia/epidemiología , Criptococosis/diagnóstico , Criptococosis/veterinaria , Infecciones por VIH/veterinaria , Humanos , Inmunoglobulina A , Inmunoglobulina G , Inmunoglobulina M
6.
Med Mycol ; 59(11): 1122-1125, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34264298

RESUMEN

Cryptococcosis by Cryptococcus gattii is endemic in Colombia, affecting mostly immunocompetent hosts. Since antifungal susceptibility differs between molecular types of cryptococcal isolates, as reported elsewhere, the aim of this study was to determine if 42 Colombian clinical isolates, VGI, VGII and VGIII, differ in the susceptibility to commonly used antifungals, using Sensititre plates. Among the molecular types, six non-wild type isolates to fluconazole, voriconazole, and 5-flucytosine, were identified. Besides, VGI and VGII were less susceptible to 5-flucytosine and azoles, respectively, than other molecular types. These findings support the applicability of practicing susceptibility testing, which could better guide treatment in cryptococcosis. LAY SUMMARY: Cryptococcosis gattii affects immunocompetent people. For a correct treatment, antifungal susceptibility testing is essential. This study shows differences in the susceptibility to commonly used antimycotics among genotypes of Colombian clinical C. gattii isolates, some of which are non-wild-type.


Asunto(s)
Antifúngicos/uso terapéutico , Criptococosis/tratamiento farmacológico , Cryptococcus gattii/efectos de los fármacos , Cryptococcus gattii/genética , Farmacorresistencia Fúngica/efectos de los fármacos , Farmacorresistencia Fúngica/genética , Adulto , Anciano , Colombia , Susceptibilidad a Enfermedades , Femenino , Variación Genética , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Serogrupo
7.
Mem Inst Oswaldo Cruz ; 115: e200430, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33053052

RESUMEN

Despite the medical advances and interventions to improve the quality of life of those in intensive care, people with cancer or severely immunocompromised or other susceptible hosts, invasive fungal diseases (IFD) remain severe and underappreciated causes of illness and death worldwide. Therefore, IFD continue to be a public health threat and a major hindrance to the success of otherwise life-saving treatments and procedures. Globally, hundreds of thousands of people are affected every year with Candida albicans, Aspergillus fumigatus, Cryptococcus neoformans, Pneumocystis jirovecii, endemic dimorphic fungi and Mucormycetes, the most common fungal species causing invasive diseases in humans. These infections result in morbidity and mortality rates that are unacceptable and represent a considerable socioeconomic burden. Raising the general awareness of the significance and impact of IFD in human health, in both the hospital and the community, is hence critical to understand the scale of the problem and to raise interest to help fighting these devastating diseases.


Asunto(s)
Hongos , Infecciones Fúngicas Invasoras/diagnóstico , Costo de Enfermedad , Hongos/clasificación , Hongos/aislamiento & purificación , Humanos , Huésped Inmunocomprometido , Unidades de Cuidados Intensivos , Infecciones Fúngicas Invasoras/complicaciones , Infecciones Fúngicas Invasoras/mortalidad , Calidad de Vida
8.
Can J Infect Dis Med Microbiol ; 2020: 3713241, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33144899

RESUMEN

Cryptococcosis, a life-threatening mycosis caused mainly by Cryptococcus neoformans, appears to be distinctly rare in hematopoietic stem cell transplant (HSCT) recipients. When it occurs, this fungal infection is a major limitation for a successful transplant. This review comprehensively analyses 24 cases, reported in the literature, of patients with haematological malignancies including leukemias, multiple myeloma, and lymphomas, as indication for HSCT, who presented with cryptococcosis after transplantation. Of the 24 cases, 11 each occurred in patients receiving allogeneic and autologous stem cell transplants, from bone marrow, peripheral blood, and umbilical cord blood. HSCT recipients were slightly more often male, and the age of the patients ranged from 12 to 74 years. Antifungal prophylaxis was reported in most cases. Clinical manifestations of cryptococcal disease included more frequently central nervous system involvement followed by fungaemia, disseminated infection, pulmonary cryptococcosis, cerebellitis, and diarrhea. Diagnosis differed depending on the clinical presentation but habitually included cryptococcal antigen assay, India ink, and culture. Notably, not only C. neoformans but also C. albidus, C. terreus, C. laurentii, and C. adeliensis were identified as the causal species, the last two including strains resistant to fluconazole. Amphotericin B, alone or in combination, was the most common antifungal drug used for the treatment of cryptococcosis in HSCT recipients. Due to the small number of cases, it was not possible to establish if mortality rate, which was the same as survival rate, depends on the effect of the immunosuppressive regimen, the site of cryptococcal infection, and/or the antifungal therapy used to control the mycosis. Although uncommon, the recognition of cryptococcal disease in stem cell transplant is essential for a timely and adequate treatment, improved prognosis, reduced morbidity and mortality, and successful transplantation.

9.
Mem Inst Oswaldo Cruz ; 113(7): e170554, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29641639

RESUMEN

Cryptococcosis is a life-threatening fungal infection caused by the encapsulated yeasts Cryptococcus neoformans and C. gattii, acquired from the environment. In Latin America, as occurring worldwide, C. neoformans causes more than 90% of the cases of cryptococcosis, affecting predominantly patients with HIV, while C. gattii generally affects otherwise healthy individuals. In this region, cryptococcal meningitis is the most common presentation, with amphotericin B and fluconazole being the antifungal drugs of choice. Avian droppings are the predominant environmental reservoir of C. neoformans, while C. gattii is associated with several arboreal species. Importantly, C. gattii has a high prevalence in Latin America and has been proposed to be the likely origin of some C. gattii populations in North America. Thus, in the recent years, significant progress has been made with the study of the basic biology and laboratory identification of cryptococcal strains, in understanding their ecology, population genetics, host-pathogen interactions, and the clinical epidemiology of this important mycosis in Latin America.


Asunto(s)
Criptococosis/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Antifúngicos/uso terapéutico , Criptococosis/diagnóstico , Criptococosis/tratamiento farmacológico , Humanos , América Latina/epidemiología
10.
J Clin Microbiol ; 53(8): 2753-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26019205

RESUMEN

We describe a fatal case of polymicrobial meningitis in a human immunodeficiency virus-infected patient from Guatemala caused by Cryptococcus liquefaciens and Mycobacterium tuberculosis complex. Central nervous system infections caused concurrently by these species are extremely rare. This is also the first report of disseminated disease caused by C. liquefaciens.


Asunto(s)
Coinfección/diagnóstico , Cryptococcus/aislamiento & purificación , Infecciones por VIH/complicaciones , Meningitis Criptocócica/diagnóstico , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis Meníngea/diagnóstico , Adulto , Análisis por Conglomerados , Coinfección/patología , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Resultado Fatal , Femenino , Guatemala , Humanos , Meningitis Criptocócica/complicaciones , Meningitis Criptocócica/patología , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Tuberculosis Meníngea/complicaciones , Tuberculosis Meníngea/patología
11.
Infect Immun ; 82(7): 3058-65, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24799631

RESUMEN

Compared to Cryptococcus neoformans, little is known about the virulence of the molecular types in Cryptococcus gattii. We compared in vitro virulence factor production and survival data using a Drosophila model of infection to further characterize the phenotypic features of different cryptococcal molecular types. Forty-nine different isolates were inoculated into wild-type flies and followed for survival. In vitro, isolates were assessed for growth at 30 and 37°C, melanin production, capsule size, resistance to H(2)O(2), and antifungal susceptibility. A mediator model was used to assess molecular type and virulence characteristics as predictors of survival in the fly model. VGIII was the most virulent molecular type in flies (P < 0.001). At 30°C, VGIII isolates grew most rapidly; at 37°C, VNI isolates grew best. C. gattii capsules were larger than those of C. neoformans (P < 0.001). Mediator model analysis found a strong correlation of Drosophila survival with molecular type and with growth at 30°C. We found molecular-type-specific differences in C. gattii in growth at different temperatures, melanin production, capsule size, ability to resist hydrogen peroxide, and antifungal susceptibility, while growth at 30°C and the VGIII molecular type were strongly associated with virulence in a Drosophila model of infection.


Asunto(s)
Cryptococcus gattii/genética , Cryptococcus gattii/patogenicidad , Drosophila melanogaster/microbiología , Animales , Antifúngicos/uso terapéutico , Cryptococcus gattii/citología , Cryptococcus gattii/efectos de los fármacos , Cryptococcus gattii/fisiología , Farmacorresistencia Fúngica , Regulación Bacteriana de la Expresión Génica , Melaninas/metabolismo , Virulencia
12.
J Clin Microbiol ; 52(6): 2061-70, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24696030

RESUMEN

Molecular types of the Cryptococcus neoformans/Cryptococcus gattii species complex that infect dogs and cats differ regionally and with host species. Antifungal drug susceptibility can vary with molecular type, but the susceptibility of Cryptococcus isolates from dogs and cats is largely unknown. Cryptococcus isolates from 15 dogs and 27 cats were typed using URA5 restriction fragment length polymorphism analysis (RFLP), PCR fingerprinting, and multilocus sequence typing (MLST). Susceptibility was determined using a microdilution assay (Sensititre YeastOne; Trek Diagnostic Systems). MICs were compared among groups. The 42 isolates studied comprised molecular types VGI (7%), VGIIa (7%), VGIIb (5%), VGIIc (5%), VGIII (38%), VGIV (2%), VNI (33%), and VNII (2%), as determined by URA5 RFLP. The VGIV isolate was more closely related to VGIII according to MLST. All VGIII isolates were from cats. All sequence types identified from veterinary isolates clustered with isolates from humans. VGIII isolates showed considerable genetic diversity compared with other Cryptococcus molecular types and could be divided into two major subgroups. Compared with C. neoformans MICs, C. gattii MICs were lower for flucytosine, and VGIII MICs were lower for flucytosine and itraconazole. For all drugs except itraconazole, C. gattii isolates exhibited a wider range of MICs than C. neoformans. MICs varied with Cryptococcus species and molecular type in dogs and cats, and MICs of VGIII isolates were most variable and may reflect phylogenetic diversity in this group. Because sequence types of dogs and cats reflect those infecting humans, these observations may also have implications for treatment of human cryptococcosis.


Asunto(s)
Antifúngicos/farmacología , Enfermedades de los Gatos/microbiología , Criptococosis/veterinaria , Cryptococcus/clasificación , Cryptococcus/efectos de los fármacos , Enfermedades de los Perros/microbiología , Filogenia , Animales , Gatos , Análisis por Conglomerados , Criptococosis/microbiología , Cryptococcus/genética , Cryptococcus/aislamiento & purificación , Dermatoglifia del ADN , Perros , Femenino , Variación Genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Técnicas de Tipificación Micológica , América del Norte , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN
13.
FEMS Yeast Res ; 14(6): 897-909, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24981157

RESUMEN

Cryptococcosis represents a fungal disease acquired from the environment with animals serving as host sentinels for human exposure. The aim of this study was to investigate the genetic characteristics of Cryptococcus isolates from veterinary sources (cats, dogs and birds) to understand their epidemiology and the genetic variability of the casual isolates. Mating-type PCR in connection with MLST analysis using the ISHAM consensus MLST scheme for the C. neoformans/C. gattii species complex was used to genotype 17 C. neoformans isolates. In the absence of an MLST typing scheme Cryptococcus adeliensis, C. albidus, C. aureus, C. carnescens, C. laurentii, C. magnus and C. uniguttulatus strains were typed using M13 PCR fingerprinting. All C. neoformans isolates were MATα mating type, but hybrids possessed αADa and aADα mating and serotypes. Two C. neoformans molecular types VNI, VNIV and VNIII and VNII/VNIV hybrids were identified. Amongst the 66 non-C. neoformans strains investigated 55 M13 PCR fingerprinting types were identified. The wide variety of MLST types of C. neoformans and the occurrence of αADa and aADα hybrids in our study supports the notion of genetic recombination in the area studied. The heterogeneity of the non-C. neoformans isolates remains open to further investigations and should be taken into consideration when identifying emergent pathogens.


Asunto(s)
Cryptococcus/clasificación , Cryptococcus/genética , Animales , Portador Sano/microbiología , Gatos , Cryptococcus/aislamiento & purificación , Cryptococcus neoformans/clasificación , Cryptococcus neoformans/genética , Cryptococcus neoformans/aislamiento & purificación , Dermatoglifia del ADN , Perros , Humanos , Italia , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Filogenia , Filogeografía
14.
Med Mycol ; 52(6): 659-66, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24951721

RESUMEN

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) offers an effective alternative to phenotypic and molecular methods for the rapid identification of microorganisms. Our aim in this study was to create an in-house library for a set of strains of nine uncommonly reported human and animal cryptococcal species, including Cryptococcus adeliensis, C. albidosimilis, C. albidus, C. aureus, C. carnescens, C. laurentii, C. magnus, C. victoriae and C. uniguttulatus, and to use this library to make timely and correct identifications using MALDI-TOF MS for use in routine laboratory diagnostics. Protein extracts obtained via the formic acid extraction method of 62 veterinary non-C. neoformans-C. gattii cryptococcal isolates were studied. The obtained mass spectra correctly grouped all 62 studied isolates according to species identification previously obtained by internal transcribe spacer sequence analysis. The in-house database was than exported and successfully uploaded to the Microflex LT (Maldi Biotyper; Bruker Daltonics) instrument at a different diagnostic laboratory in Italy. Scores >2.7 obtained from isolates reanalyzed in the latter laboratory supported the high reproducibility of the method. The possibility of creating and transferring an in-house library adds to the usefulness MALDI-TOF MS an important tool for the rapid and inexpensive identification of pathogenic and saprophytic fungi as required for differential diagnosis of human and animal mycoses.


Asunto(s)
Criptococosis/diagnóstico , Criptococosis/microbiología , Cryptococcus/química , Cryptococcus/clasificación , Técnicas Microbiológicas/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Cryptococcus/aislamiento & purificación , Proteínas Fúngicas/análisis , Proteínas Fúngicas/aislamiento & purificación , Humanos , Italia
15.
J Fungi (Basel) ; 10(5)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38786681

RESUMEN

Increasingly common and associated with healthcare settings, Candida infections are very important, since some species of this genus can develop antifungal resistance. We contribute data on the epidemiology, antifungal susceptibility, and genetic diversity of Candida non-albicans and non-auris affecting critically ill patients in a fourth-level hospital in Colombia. Ninety-seven isolates causing invasive infections, identified by conventional methods over 18 months, were studied. Data from patients affected by these yeasts, including sex, age, comorbidities, treatment, and outcome, were analysed. The antifungal susceptibility of the isolates was determined, and the ribosomal DNA was sequenced. Candida parapsilosis, Candida tropicalis, Candida glabrata, Candida dubliniensis, and Candida guilliermondii caused 48.5% of all cases of invasive candidiasis. The species were mainly recovered from blood (50%). Patients were mostly men (53.4%), between 18 days and 93 years old, hospitalized in the ICU (70.7%). Overall mortality was 46.6%, but patients in the ICU, using antibiotics, with diabetes mellitus, or with C. glabrata infections were more likely to die. Resistant isolates were identified in C. parapsilosis, C. tropicalis, and C. glabrata. This study provides epidemiological data for the surveillance of emerging Candida species, highlighting their clinical impact, as well as the emergence of antifungal resistance and clonal dispersal.

16.
Front Cell Infect Microbiol ; 14: 1389020, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601736

RESUMEN

Introduction: Invasive candidiasis is a global public health problem as it poses a significant threat in hospital-settings. The aim of this study was to evaluate C14R, an analog derived from peptide BP100, as a potential antimicrobial peptide against the prevalent opportunistic yeast Candida albicans and the emergent multidrug-resistant yeast Candida auris. Methods: Antifungal susceptibility testing of C14R against 99 C. albicans and 105 C. auris clinical isolates from Colombia, was determined by broth microdilution. Fluconazole was used as a control antifungal. The synergy between C14R and fluconazole was assessed in resistant isolates. Assays against fungal biofilm and growth curves were also carried out. Morphological alterations of yeast cell surface were evaluated by scanning electron microscopy. A permeability assay verified the pore-forming ability of C14R. Results: C. albicans and C. auris isolates had a geometric mean MIC against C14R of 4.42 µg/ml and 5.34 µg/ml, respectively. Notably, none of the isolates of any species exhibited growth at the highest evaluated peptide concentration (200 µg/ml). Synergistic effects were observed when combining the peptide and fluconazole. C14R affects biofilm and growth of C. albicans and C. auris. Cell membrane disruptions were observed in both species after treatment with the peptide. It was confirmed that C14R form pores in C. albicans' membrane. Discussion: C14R has a potent antifungal activity against a large set of clinical isolates of both C. albicans and C. auris, showing its capacity to disrupt Candida membranes. This antifungal activity remains consistent across isolates regardless of their clinical source. Furthermore, the absence of correlation between MICs to C14R and resistance to fluconazole indicates the peptide's potential effectiveness against fluconazole-resistant strains. Our results suggest the potential of C14R, a pore-forming peptide, as a treatment option for fungal infections, such as invasive candidiasis, including fluconazole and amphotericin B -resistant strains.


Asunto(s)
Antifúngicos , Candidiasis Invasiva , Candidiasis , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida albicans , Fluconazol/farmacología , Fluconazol/uso terapéutico , Candida auris , Péptidos/farmacología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica
17.
Res Sq ; 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38313298

RESUMEN

Background: Cryptococcosis is a life-threatening disease caused by Cryptococcus neoformans or C. gattii. Autoantibodies (auto-Abs) neutralizing granulocyte-macrophage colony-stimulating factor (GM-CSF) in otherwise healthy adults with cryptococcal meningitis have been described since 2013. We searched for neutralizing auto-Abs in sera from Colombian patients with non-HIV related cryptococcosis in a retrospective national cohort collected from 1997 to 2016. Methods: We reviewed clinical and laboratory records and assessed the presence of neutralizing auto-Abs in 30 HIV (-) adults presenting cryptococcosis (13 by C. gattii, and 17 by C. neoformans). Results: We detected auto-Abs neutralizing GM-CSF in the plasma of 9 out of 13 (69%) patients infected with C. gattii and 1 out of 17 (6%) patients with C. neoformans. Conclusions: We report ten Colombian patients with cryptococcosis due to auto-Abs neutralizing GM-CSF. Nine of the ten patients were infected with C. gattii, and only one with C. neoformans.

18.
Microbiol Spectr ; 11(4): e0140323, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37341584

RESUMEN

Cryptococcus neoformans and Cryptococcus gattii cause cryptococcosis, a life-threatening fungal infection affecting mostly immunocompromised patients. In fact, cryptococcal meningitis accounts for about 19% of AIDS-related deaths in the world. Because of long-term azole therapies to treat this mycosis, resistance to fluconazole leading to treatment failure and poor prognosis has long been reported for both fungal species. Among the mechanisms implicated in resistance to azoles, mutations in the ERG11 gene, encoding the azole target enzyme lanosterol 14-α-demethylase, have been described. This study aimed to establish the amino acid composition of ERG11 of Colombian clinical isolates of C. neoformans and C. gattii and to correlate any possible substitution with the in vitro susceptibility profile of the isolates to fluconazole, voriconazole, and itraconazole. Antifungal susceptibility testing results showed that C. gattii isolates are less susceptible to azoles than C. neoformans isolates, which could correlate with differences in the amino acid composition and structure of ERG11 of each species. In addition, in a C. gattii isolate with high MICs for fluconazole (64 µg/mL) and voriconazole (1 µg/mL), a G973T mutation resulting in the substitution R258L, located in substrate recognition site 3 of ERG11, was identified. This finding suggests the association of the newly reported substitution with the azole resistance phenotype in C. gattii. Further investigations are needed to determine the exact role that R258L plays in the decreased susceptibility to fluconazole and voriconazole, as well as to determine the participation of additional mechanisms of resistance to azole drugs. IMPORTANCE The fungal species Cryptococcus neoformans and C. gattii are human pathogens for which drug resistance or other treatment and management challenges exist. Here, we report differential susceptibility to azoles among both species, with some isolates displaying resistant phenotypes. Azoles are among the most commonly used drugs to treat cryptococcal infections. Our findings underscore the necessity of testing antifungal susceptibility in the clinical setting in order to assist patient management and beneficial outcomes. In addition, we report an amino acid change in the sequence of the target protein of azoles, which suggests that this change might be implicated in resistance to these drugs. Identifying and understanding possible mechanisms that affect drug affinity will eventually aid the design of new drugs that overcome the global growing concern of antifungal resistance.


Asunto(s)
Criptococosis , Cryptococcus gattii , Cryptococcus neoformans , Humanos , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Cryptococcus gattii/genética , Fluconazol/farmacología , Azoles/farmacología , Voriconazol/farmacología , Lanosterol/farmacología , Lanosterol/uso terapéutico , Esterol 14-Desmetilasa/genética , Esterol 14-Desmetilasa/metabolismo , Esterol 14-Desmetilasa/farmacología , Cryptococcus neoformans/genética , Criptococosis/tratamiento farmacológico , Criptococosis/microbiología , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica/genética , Aminoácidos
19.
Pharmaceutics ; 15(3)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36986650

RESUMEN

Expanding the antifungal drug arsenal for treating Candida infections is crucial in this era of the rising life expectancy of patients with immunosuppression and comorbidities. Infections caused by Candida species are on the rise, including those caused by multidrug-resistant strains or species, and the list of antifungals approved for the treatment of these infections is still limited. Antimicrobial peptides (AMPs) are short cationic polypeptides whose antimicrobial activity is under intense investigation. In this review, we present a comprehensive summary of the AMPs with anti-Candida activity that have undergone successful preclinical or clinical trials. Their source, mode of action, and animal model of infection (or clinical trial) are presented. In addition, as some of these AMPs have been tested in combination therapy, the advantages of this approach, as well as the studied cases that have used AMPs and other drugs concomitantly to fight Candida infections, are described.

20.
J Fungi (Basel) ; 9(7)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37504735

RESUMEN

Systemic infections caused by rare yeasts are increasing given the rise in immunocompromised or seriously ill patients. Even though globally, the clinical significance of these emerging opportunistic yeasts is increasingly being recognized, less is known about the epidemiology of rare yeasts in Latin America. This review collects, analyzes, and contributes demographic and clinical data from 495 cases of infection caused by rare yeasts in the region. Among all cases, 32 species of rare yeasts, distributed in 12 genera, have been reported in 8 Latin American countries, with Trichosporon asahii (49.5%), Rhodotorula mucilaginosa (11.1%), and Saccharomyces cerevisiae (7.8%) the most common species found. Patients were mostly male (58.3%), from neonates to 84 years of age. Statistically, surgery and antibiotic use were associated with higher rates of Trichosporon infections, while central venous catheter, leukemia, and cancer were associated with higher rates of Rhodotorula infections. From all cases, fungemia was the predominant diagnosis (50.3%). Patients were mostly treated with amphotericin B (58.7%). Crude mortality was 40.8%, with a higher risk of death from fungemia and T. asahii infections. Culture was the main diagnostic methodology. Antifungal resistance to one or more drugs was reported in various species of rare yeasts.

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