RESUMO
Chitin is a polymer of N-acetylglucosamine and an essential component of the fungal cell wall. Chitosan is the deacetylated form of chitin and is also important for maintaining the integrity of this structure. Both polysaccharides are widely distributed in nature and have been shown to have a variety of applications in biomedicine, including their potential in immune sensing and as potential antifungal agents. In addition, chitin has been reported to play an important role in the pathogen-host interaction, involving innate and adaptive immune responses. This paper will explore the role of chitin and chitosan when incorporated into nanobiocomposites to improve their efficacy in detecting fungi of medical interest and inhibiting their growth. Potential applications in diagnostic and therapeutic medicine will be discussed, highlighting their promise in the development of more sensitive and effective tools for the early diagnosis of fungal infections. This review aims to highlight the importance of the convergence of nanotechnology and biology in addressing public health challenges.
Assuntos
Antifúngicos , Quitina , Quitosana , Fungos , Quitina/química , Quitina/farmacologia , Quitosana/química , Quitosana/farmacologia , Antifúngicos/farmacologia , Antifúngicos/química , Fungos/efeitos dos fármacos , Fungos/química , Humanos , Nanocompostos/química , Micoses/imunologia , Micoses/tratamento farmacológico , Micoses/diagnósticoRESUMO
The emergence of fungal pathogens and changes in the epidemiological landscape are prevalent issues in clinical mycology. Reports of resistance to antifungals have been reported. This review aims to evaluate molecular and nonmolecular mechanisms related to antifungal resistance. Mutations in the ERG genes and overexpression of the efflux pump (MDR1, CDR1 and CDR2 genes) were the most reported molecular mechanisms of resistance in clinical isolates, mainly related to Azoles. For echinocandins, a molecular mechanism described was mutation in the FSK genes. Furthermore, nonmolecular virulence factors contributed to therapeutic failure, such as biofilm formation and selective pressure due to previous exposure to antifungals. Thus, there are many public health challenges in treating fungal infections.
[Box: see text].
Assuntos
Antifúngicos , Farmacorresistência Fúngica , Fungos , Micoses , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica/genética , Humanos , Micoses/microbiologia , Micoses/tratamento farmacológico , Micoses/epidemiologia , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/patogenicidade , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Mutação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Azóis/farmacologia , Azóis/uso terapêutico , Testes de Sensibilidade Microbiana , Fatores de Virulência/genética , Equinocandinas/farmacologia , Equinocandinas/uso terapêuticoRESUMO
Osteomyelitis caused by non-Candida species is rare and often neglected, and current recommendations are based on primarily clinical experience and expert opinion. The objective of this study was to describe a case series of non-Candida fungal osteomyelitis. This retrospective study included 10 patients with non-Candida fungal osteomyelitis. Patients with osteomyelitis and microbiologically confirmed non-Candida species from bone fragment cultures were selected from the institution Infection Control Board database. Fusarium spp. were the most commonly isolated fungus from bone fragment cultures in five patients (50%). The majority did not present immunosuppression. The most common etiology was post-traumatic (n = 7, 70%), particularly open fractures. All patients were treated with antifungals associated with surgery. The antifungals used were itraconazole in five patients (50%), and voriconazole in another five patients (50%), with a median duration of antifungal therapy of four weeks (range: 3-25). There were no observed deaths within 30 days and one year. An antifungal approach combined with surgical treatment demonstrated favorable clinical outcomes, including low mortality rates and effective remission.
Assuntos
Antifúngicos , Osteomielite , Humanos , Osteomielite/microbiologia , Osteomielite/epidemiologia , Osteomielite/tratamento farmacológico , Antifúngicos/uso terapêutico , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Feminino , Adulto , Adulto Jovem , Idoso , Adolescente , Micoses/microbiologia , Micoses/epidemiologia , Micoses/tratamento farmacológico , Micoses/mortalidade , Fungos/isolamento & purificação , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , CriançaRESUMO
Chromoblastomycosis (CBM) and pheohyphomycosis (PHM) are the most common implantation mycoses caused by dematiaceous fungi. In the past, flucytosine (5-FC) has been used to treat CBM, but development of resistance is common. Carmofur belongs to the same class as 5-FC and has in vitro inhibitory activity against the main agents of CBM and PHM. The aim of this study was to compare the action of these two pyrimidine analog drugs against CBM and PHM agents. The minimum inhibitory concentration (MIC) and the selectivity index based on cytotoxicity tests of these two drugs against some agents of these mycoses were determined, with carmofur presenting a higher selectivity index than 5-FC. Carmofur demonstrated here synergistic interactions with itraconazole and amphotericin B against Exophiala heteromorpha, Fonsecaea pedrosoi, Fonsecaea monophora, and Fonsecaea nubica strains. Additionally, carmofur plus itraconazole demonstrated here synergism against a Phialophora verrucosa strain. To evaluate the development of carmofur resistance, passages in culture medium containing subinhibitory concentrations of this pyrimidine analog were carried out, followed by in vitro susceptibility tests. Exophiala dermatitidis quickly developed resistance, whereas F. pedrosoi took seven passages in carmofur-supplemented medium to develop resistance. Moreover, resistance was permanent in E. dermatitidis but transient in F. pedrosoi. Hence, carmofur has exhibited certain advantages, albeit accompanied by limitations such as the development of resistance, which was expected as with 5-FC. This underscores its therapeutic potential in combination with other drugs, emphasizing the need for a meticulous evaluation of its application in the fight against dematiaceous fungi.
Assuntos
Cromoblastomicose , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Flucitosina/farmacologia , Itraconazol/farmacologia , Itraconazol/uso terapêutico , Fungos , Cromoblastomicose/microbiologia , Cromoblastomicose/veterinária , Micoses/tratamento farmacológico , Micoses/veterinária , Testes de Sensibilidade Microbiana/veterináriaRESUMO
Diagnosis and management of fungal infections are challenging in both animals and humans, especially in immunologically weakened hosts. Due to its broad spectrum and safety profile when compared to other antifungals, itraconazole (ITZ) has been widely used in the treatment and prophylaxis of fungal infections, both in human and veterinary medicine. The dose and duration of management depend on factors such as the type of fungal pathogen, the site of infection, sensitivity to ITZ, chronic stages of the disease, the health status of the hosts, pharmacological interactions with other medications and the therapeutic protocol used. In veterinary practice, ITZ doses generally vary between 3 mg/kg and 50 mg/kg, once or twice a day. In humans, doses usually vary between 100 and 400 mg/day. As human and veterinary fungal infections are increasingly associated, and ITZ is one of the main medications used, this review addresses relevant aspects related to the use of this drug in both clinics, including case reports and different clinical aspects available in the literature.
Assuntos
Antifúngicos , Itraconazol , Micoses , Humanos , Antifúngicos/uso terapêutico , Antifúngicos/administração & dosagem , Itraconazol/uso terapêutico , Micoses/tratamento farmacológico , Micoses/veterinária , Micoses/microbiologia , Animais , Medicina Veterinária/métodosRESUMO
Opportunistic fungal infections represent a global health problem, mainly for immunocompromised individuals. New therapeutical options are needed since several fungal strains show resistance to clinically available antifungal agents. 2-Thiazolylhydrazones are well-known as potent compounds against Candida and Cryptococcus species. A scaffold-focused drug design using machine-learning models was established to optimize the 2-thiazolylhydrazone skeleton and obtain novel compounds with higher potency, better solubility in water, and enhanced absorption. Twenty-nine novel compounds were obtained and most showed low micromolar MIC values against different species of Candida and Cryptococcus spp., including Candida auris, an emerging multidrug-resistant yeast. Among the synthesized compounds, 2-thiazolylhydrazone 28 (MIC value ranging from 0.8 to 52.17 µM) was selected for further studies: cytotoxicity evaluation, permeability study in Caco-2 cell model, and in vivo efficacy against Cryptococcus neoformans in an invertebrate infection model. All results obtained indicate the great potential of 28 as a novel antifungal agent.
Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Células CACO-2 , Testes de Sensibilidade Microbiana , Candida , Micoses/tratamento farmacológicoRESUMO
INTRODUCTION: Fungal infections are caused by a broad range of pathogenic fungi that are found worldwide with different geographic distributions, incidences, and mortality rates. Considering that there are relatively few approved medications available for combating fungal diseases and no vaccine formulation commercially available, multiple groups are searching for new antifungal drugs, examining drugs for repurposing and developing antifungal vaccines, in order to control deaths, sequels, and the spread of these complex infections. AREAS COVERED: This review provides a summary of advances in fungal vaccine studies and the different approaches under development, such as subunit vaccines, whole organism vaccines, and DNA vaccines, as well as studies that optimize the use of adjuvants. We conducted a literature search of the PubMed with terms: fungal vaccines and genus of fungal pathogens (Cryptococcus spp. Candida spp. Coccidioides spp. Aspergillus spp. Sporothrix spp. Histoplasma spp. Paracoccidioides spp. Pneumocystis spp. and the Mucorales order), a total of 177 articles were collected from database. EXPERT OPINION: Problems regarding the immune response development in an immunocompromised organism, the similarity between fungal and mammalian cells, and the lack of attention by health organizations to fungal infections are closely related to the fact that, at present, there are no fungal vaccines available for clinical use.
Assuntos
Micoses , Vacinas , Animais , Humanos , Antifúngicos/uso terapêutico , Fungos , Micoses/prevenção & controle , Micoses/tratamento farmacológico , Micoses/epidemiologia , Vacinas/uso terapêutico , Desenvolvimento de Vacinas , MamíferosRESUMO
INTRODUCTION: Cladophialophora bantiana is a filamentous fungus, known as a dematiaceous fungus because of the presence of melanin. This fungus is of clinical importance because it is neurotropic and causes cerebral phaeohyphomycosis. MATERIAL AND METHODS: The available scientific information on the development of cerebral phaeohyphomycosis caused by Cladophialophora bantiana was analysed by selecting articles from the PubMed, Scopus and Google Scholar databases that describe case reports of fungal infection by C. bantiana in adults, taking into account the analysis of the patients' symptomatology, clinical history and neuroanatomical damage, in addition to considering the mortality of the condition. RESULTS: India and United States were the countries with most case reports, with 32 and 11 cases respectively. Moreover, in terms of neuroanatomical lesions, the majority of patients suffered mixed lesions (29%) and frontal lobe lesions (22%). In accordance with the patients' condition, the pathology has a mortality rate of 62%. CONCLUSIONS: It is concluded that cerebral phaeohyphomycosis has a high mortality rate, there is no standardised treatment and, in most cases, the fungal infection of the brain is mixed and affects several different parts of it. Furthermore, if not diagnosed and treated in time, it can lead to the patients' death.
TITLE: Infección micótica por Cladophialophora bantiana y desarrollo de feohifomicosis cerebral. Revisión sistemática de 58 informes de caso.Introducción. Cladophialophora bantiana es un hongo filamentoso, denominado hongo dematiáceo por la presencia de melanina. Este hongo tiene importancia clínica por ser neurotrópico y causar feohifomicosis cerebral. Material y métodos. Se analizó la información científica disponible sobre el desarrollo de feohifomicosis cerebral provocada por Cladophialophora bantiana, seleccionando artículos de las bases de PubMed, Scopus y Google Scholar, que describen informes de caso sobre infección micótica de C. bantiana en adultos, considerando el análisis de la sintomatología, el historial clínico y los daños neuroanatómicos de los pacientes, además de considerar la mortalidad de la patología. Resultados. La India y Estados Unidos fueron los países con más informes de caso, 32 y 11 casos, respectivamente. Asimismo, en cuanto a las lesiones neuroanatómicas, en su mayoría, los pacientes sufrieron lesiones mixtas (29%) y del lóbulo frontal (22%). De acuerdo con el estado de los pacientes, la patología tiene una mortalidad del 62%. Conclusiones. Se concluye que la feohifomicosis cerebral tiene una alta mortalidad, no existe un tratamiento estandarizado y, en la mayoría de los casos, la infección fúngica del cerebro es mixta y afecta a varias partes del cerebro; además, si no se diagnostica y trata a tiempo, puede ocasionar la muerte de los pacientes.
Assuntos
Ascomicetos , Abscesso Encefálico , Feoifomicose Cerebral , Micoses , Adulto , Humanos , Antifúngicos/uso terapêutico , Abscesso Encefálico/tratamento farmacológico , Feoifomicose Cerebral/diagnóstico , Feoifomicose Cerebral/tratamento farmacológico , Micoses/tratamento farmacológico , Relatos de Casos como AssuntoRESUMO
BACKGROUND: Fungal endocarditis is a low-frequency disease with a challenging diagnosis, as it can be mistaken with bacterial endocarditis. Fungal endocarditis causes higher mortality rates in immunocompromised patients. In the clinical practice, the endocarditis caused by fungi represents up to 10% of all infectious endocarditis cases and has a mortality rate of nearly 50%. CASE REPORT: Here we present the case of a 53-year-old woman under corticosteroid therapy with a history of rheumatic heart disease, aortic valve replacement, and rheumatoid arthritis, who presented with fungal endocarditis caused by Candida albicans. Even though the patient received 3 years of antifungal prophylaxis with fluconazole, had valve replacement surgery, and received intensive care, the patient finally worsened and died. CONCLUSIONS: Comorbidities and corticosteroid therapy predisposed the patient to acquire fungal endocarditis. This case highlights the importance of implementing procedures for the isolation and identification of fungi, and for carrying out antifungal-susceptibility testing, as well as establishing surveillance programs to identify infection-causing species and drug resistance patterns in hospitals. Moreover, designing and upgrading the algorithm for infectious endocarditis is the key to future improvements in diagnosis.